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4.16 hdmi #25

Merged
merged 2 commits into from
May 26, 2018
Merged

4.16 hdmi #25

merged 2 commits into from
May 26, 2018

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d3adme4t
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Added CONFIG_INPUT_MOUSEDEV for /dev/input/mice support, which is needed for gpm packet.
Removed CONFIG_INPUT_EVBUG.

d3adme4t added 2 commits May 25, 2018 14:23
…f gpm in fb console.

Removed CONFIG_INPUT_EVBUG mich makes a lot of unnesessary debug info in dmesg.
@frank-w frank-w merged commit 2435231 into frank-w:4.16-hdmi May 26, 2018
frank-w pushed a commit that referenced this pull request Jul 3, 2018
commit d50d82f upstream.

In kernel 4.17 I removed some code from dm-bufio that did slab cache
merging (commit 21bb132: "dm bufio: remove code that merges slab
caches") - both slab and slub support merging caches with identical
attributes, so dm-bufio now just calls kmem_cache_create and relies on
implicit merging.

This uncovered a bug in the slub subsystem - if we delete a cache and
immediatelly create another cache with the same attributes, it fails
because of duplicate filename in /sys/kernel/slab/.  The slub subsystem
offloads freeing the cache to a workqueue - and if we create the new
cache before the workqueue runs, it complains because of duplicate
filename in sysfs.

This patch fixes the bug by moving the call of kobject_del from
sysfs_slab_remove_workfn to shutdown_cache.  kobject_del must be called
while we hold slab_mutex - so that the sysfs entry is deleted before a
cache with the same attributes could be created.

Running device-mapper-test-suite with:

  dmtest run --suite thin-provisioning -n /commit_failure_causes_fallback/

triggered:

  Buffer I/O error on dev dm-0, logical block 1572848, async page read
  device-mapper: thin: 253:1: metadata operation 'dm_pool_alloc_data_block' failed: error = -5
  device-mapper: thin: 253:1: aborting current metadata transaction
  sysfs: cannot create duplicate filename '/kernel/slab/:a-0000144'
  CPU: 2 PID: 1037 Comm: kworker/u48:1 Not tainted 4.17.0.snitm+ #25
  Hardware name: Supermicro SYS-1029P-WTR/X11DDW-L, BIOS 2.0a 12/06/2017
  Workqueue: dm-thin do_worker [dm_thin_pool]
  Call Trace:
   dump_stack+0x5a/0x73
   sysfs_warn_dup+0x58/0x70
   sysfs_create_dir_ns+0x77/0x80
   kobject_add_internal+0xba/0x2e0
   kobject_init_and_add+0x70/0xb0
   sysfs_slab_add+0xb1/0x250
   __kmem_cache_create+0x116/0x150
   create_cache+0xd9/0x1f0
   kmem_cache_create_usercopy+0x1c1/0x250
   kmem_cache_create+0x18/0x20
   dm_bufio_client_create+0x1ae/0x410 [dm_bufio]
   dm_block_manager_create+0x5e/0x90 [dm_persistent_data]
   __create_persistent_data_objects+0x38/0x940 [dm_thin_pool]
   dm_pool_abort_metadata+0x64/0x90 [dm_thin_pool]
   metadata_operation_failed+0x59/0x100 [dm_thin_pool]
   alloc_data_block.isra.53+0x86/0x180 [dm_thin_pool]
   process_cell+0x2a3/0x550 [dm_thin_pool]
   do_worker+0x28d/0x8f0 [dm_thin_pool]
   process_one_work+0x171/0x370
   worker_thread+0x49/0x3f0
   kthread+0xf8/0x130
   ret_from_fork+0x35/0x40
  kobject_add_internal failed for :a-0000144 with -EEXIST, don't try to register things with the same name in the same directory.
  kmem_cache_create(dm_bufio_buffer-16) failed with error -17

Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1806151817130.6333@file01.intranet.prod.int.rdu2.redhat.com
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Mike Snitzer <snitzer@redhat.com>
Tested-by: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Jul 3, 2018
commit d50d82f upstream.

In kernel 4.17 I removed some code from dm-bufio that did slab cache
merging (commit 21bb132: "dm bufio: remove code that merges slab
caches") - both slab and slub support merging caches with identical
attributes, so dm-bufio now just calls kmem_cache_create and relies on
implicit merging.

This uncovered a bug in the slub subsystem - if we delete a cache and
immediatelly create another cache with the same attributes, it fails
because of duplicate filename in /sys/kernel/slab/.  The slub subsystem
offloads freeing the cache to a workqueue - and if we create the new
cache before the workqueue runs, it complains because of duplicate
filename in sysfs.

This patch fixes the bug by moving the call of kobject_del from
sysfs_slab_remove_workfn to shutdown_cache.  kobject_del must be called
while we hold slab_mutex - so that the sysfs entry is deleted before a
cache with the same attributes could be created.

Running device-mapper-test-suite with:

  dmtest run --suite thin-provisioning -n /commit_failure_causes_fallback/

triggered:

  Buffer I/O error on dev dm-0, logical block 1572848, async page read
  device-mapper: thin: 253:1: metadata operation 'dm_pool_alloc_data_block' failed: error = -5
  device-mapper: thin: 253:1: aborting current metadata transaction
  sysfs: cannot create duplicate filename '/kernel/slab/:a-0000144'
  CPU: 2 PID: 1037 Comm: kworker/u48:1 Not tainted 4.17.0.snitm+ #25
  Hardware name: Supermicro SYS-1029P-WTR/X11DDW-L, BIOS 2.0a 12/06/2017
  Workqueue: dm-thin do_worker [dm_thin_pool]
  Call Trace:
   dump_stack+0x5a/0x73
   sysfs_warn_dup+0x58/0x70
   sysfs_create_dir_ns+0x77/0x80
   kobject_add_internal+0xba/0x2e0
   kobject_init_and_add+0x70/0xb0
   sysfs_slab_add+0xb1/0x250
   __kmem_cache_create+0x116/0x150
   create_cache+0xd9/0x1f0
   kmem_cache_create_usercopy+0x1c1/0x250
   kmem_cache_create+0x18/0x20
   dm_bufio_client_create+0x1ae/0x410 [dm_bufio]
   dm_block_manager_create+0x5e/0x90 [dm_persistent_data]
   __create_persistent_data_objects+0x38/0x940 [dm_thin_pool]
   dm_pool_abort_metadata+0x64/0x90 [dm_thin_pool]
   metadata_operation_failed+0x59/0x100 [dm_thin_pool]
   alloc_data_block.isra.53+0x86/0x180 [dm_thin_pool]
   process_cell+0x2a3/0x550 [dm_thin_pool]
   do_worker+0x28d/0x8f0 [dm_thin_pool]
   process_one_work+0x171/0x370
   worker_thread+0x49/0x3f0
   kthread+0xf8/0x130
   ret_from_fork+0x35/0x40
  kobject_add_internal failed for :a-0000144 with -EEXIST, don't try to register things with the same name in the same directory.
  kmem_cache_create(dm_bufio_buffer-16) failed with error -17

Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1806151817130.6333@file01.intranet.prod.int.rdu2.redhat.com
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Mike Snitzer <snitzer@redhat.com>
Tested-by: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Jul 25, 2018
commit 36eb8ff upstream.

Crash dump shows following instructions

crash> bt
PID: 0      TASK: ffffffffbe412480  CPU: 0   COMMAND: "swapper/0"
 #0 [ffff891ee0003868] machine_kexec at ffffffffbd063ef1
 #1 [ffff891ee00038c8] __crash_kexec at ffffffffbd12b6f2
 #2 [ffff891ee0003998] crash_kexec at ffffffffbd12c84c
 #3 [ffff891ee00039b8] oops_end at ffffffffbd030f0a
 #4 [ffff891ee00039e0] no_context at ffffffffbd074643
 #5 [ffff891ee0003a40] __bad_area_nosemaphore at ffffffffbd07496e
 #6 [ffff891ee0003a90] bad_area_nosemaphore at ffffffffbd074a64
 #7 [ffff891ee0003aa0] __do_page_fault at ffffffffbd074b0a
 #8 [ffff891ee0003b18] do_page_fault at ffffffffbd074fc8
 #9 [ffff891ee0003b50] page_fault at ffffffffbda01925
    [exception RIP: qlt_schedule_sess_for_deletion+15]
    RIP: ffffffffc02e526f  RSP: ffff891ee0003c08  RFLAGS: 00010046
    RAX: 0000000000000000  RBX: 0000000000000000  RCX: ffffffffc0307847
    RDX: 00000000000020e6  RSI: ffff891edbc377c8  RDI: 0000000000000000
    RBP: ffff891ee0003c18   R8: ffffffffc02f0b20   R9: 0000000000000250
    R10: 0000000000000258  R11: 000000000000b780  R12: ffff891ed9b43000
    R13: 00000000000000f0  R14: 0000000000000006  R15: ffff891edbc377c8
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #10 [ffff891ee0003c20] qla2x00_fcport_event_handler at ffffffffc02853d3 [qla2xxx]
 #11 [ffff891ee0003cf0] __dta_qla24xx_async_gnl_sp_done_333 at ffffffffc0285a1d [qla2xxx]
 #12 [ffff891ee0003de8] qla24xx_process_response_queue at ffffffffc02a2eb5 [qla2xxx]
 #13 [ffff891ee0003e88] qla24xx_msix_rsp_q at ffffffffc02a5403 [qla2xxx]
 #14 [ffff891ee0003ec0] __handle_irq_event_percpu at ffffffffbd0f4c59
 #15 [ffff891ee0003f10] handle_irq_event_percpu at ffffffffbd0f4e02
 #16 [ffff891ee0003f40] handle_irq_event at ffffffffbd0f4e90
 #17 [ffff891ee0003f68] handle_edge_irq at ffffffffbd0f8984
 #18 [ffff891ee0003f88] handle_irq at ffffffffbd0305d5
 #19 [ffff891ee0003fb8] do_IRQ at ffffffffbda02a18
 --- <IRQ stack> ---
 #20 [ffffffffbe403d30] ret_from_intr at ffffffffbda0094e
    [exception RIP: unknown or invalid address]
    RIP: 000000000000001f  RSP: 0000000000000000  RFLAGS: fff3b8c2091ebb3f
    RAX: ffffbba5a0000200  RBX: 0000be8cdfa8f9fa  RCX: 0000000000000018
    RDX: 0000000000000101  RSI: 000000000000015d  RDI: 0000000000000193
    RBP: 0000000000000083   R8: ffffffffbe403e38   R9: 0000000000000002
    R10: 0000000000000000  R11: ffffffffbe56b820  R12: ffff891ee001cf00
    R13: ffffffffbd11c0a4  R14: ffffffffbe403d60  R15: 0000000000000001
    ORIG_RAX: ffff891ee0022ac0  CS: 0000  SS: ffffffffffffffb9
 bt: WARNING: possibly bogus exception frame
 #21 [ffffffffbe403dd8] cpuidle_enter_state at ffffffffbd67c6fd
 #22 [ffffffffbe403e40] cpuidle_enter at ffffffffbd67c907
 #23 [ffffffffbe403e50] call_cpuidle at ffffffffbd0d98f3
 #24 [ffffffffbe403e60] do_idle at ffffffffbd0d9b42
 #25 [ffffffffbe403e98] cpu_startup_entry at ffffffffbd0d9da3
 #26 [ffffffffbe403ec0] rest_init at ffffffffbd81d4aa
 #27 [ffffffffbe403ed0] start_kernel at ffffffffbe67d2ca
 #28 [ffffffffbe403f28] x86_64_start_reservations at ffffffffbe67c675
 #29 [ffffffffbe403f38] x86_64_start_kernel at ffffffffbe67c6eb
 #30 [ffffffffbe403f50] secondary_startup_64 at ffffffffbd0000d5

Fixes: 040036b ("scsi: qla2xxx: Delay loop id allocation at login")
Cc: <stable@vger.kernel.org> # v4.17+
Signed-off-by: Chuck Anderson <chuck.anderson@oracle.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Oct 12, 2018
Chen Yu reported a divide-by-zero error when accessing the 'size'
resctrl file when a MBA resource is enabled.

divide error: 0000 [#1] SMP PTI
CPU: 93 PID: 1929 Comm: cat Not tainted 4.19.0-rc2-debug-rdt+ #25
RIP: 0010:rdtgroup_cbm_to_size+0x7e/0xa0
Call Trace:
rdtgroup_size_show+0x11a/0x1d0
seq_read+0xd8/0x3b0

Quoting Chen Yu's report: This is because for MB resource, the
r->cache.cbm_len is zero, thus calculating size in rdtgroup_cbm_to_size()
will trigger the exception.

Fix this issue in the 'size' file by getting correct memory bandwidth value
which is in MBps when MBA software controller is enabled or in percentage
when MBA software controller is disabled.

Fixes: d9b48c8 ("x86/intel_rdt: Display resource groups' allocations in bytes")
Reported-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Cc: "H Peter Anvin" <hpa@zytor.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "Xiaochen Shen" <xiaochen.shen@intel.com>
Link: https://lkml.kernel.org/r/20180904174614.26682-1-yu.c.chen@intel.com
Link: https://lkml.kernel.org/r/1537048707-76280-3-git-send-email-fenghua.yu@intel.com
frank-w pushed a commit that referenced this pull request Oct 12, 2018
Add missing prepare/unprepare operations for fbi->clk,
this fixes following kernel warning:

  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:874 clk_core_enable+0x2c/0x1b0
  Enabling unprepared disp0_clk
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper Not tainted 4.18.0-rc8-00032-g02b43ddd4f21-dirty #25
  Hardware name: Marvell MMP2 (Device Tree Support)
  [<c010f7cc>] (unwind_backtrace) from [<c010cc6c>] (show_stack+0x10/0x14)
  [<c010cc6c>] (show_stack) from [<c011dab4>] (__warn+0xd8/0xf0)
  [<c011dab4>] (__warn) from [<c011db10>] (warn_slowpath_fmt+0x44/0x6c)
  [<c011db10>] (warn_slowpath_fmt) from [<c043898c>] (clk_core_enable+0x2c/0x1b0)
  [<c043898c>] (clk_core_enable) from [<c0439ec8>] (clk_core_enable_lock+0x18/0x2c)
  [<c0439ec8>] (clk_core_enable_lock) from [<c0436698>] (pxa168fb_probe+0x464/0x6ac)
  [<c0436698>] (pxa168fb_probe) from [<c04779a0>] (platform_drv_probe+0x48/0x94)
  [<c04779a0>] (platform_drv_probe) from [<c0475bec>] (driver_probe_device+0x328/0x470)
  [<c0475bec>] (driver_probe_device) from [<c0475de4>] (__driver_attach+0xb0/0x124)
  [<c0475de4>] (__driver_attach) from [<c0473c38>] (bus_for_each_dev+0x64/0xa0)
  [<c0473c38>] (bus_for_each_dev) from [<c0474ee0>] (bus_add_driver+0x1b8/0x230)
  [<c0474ee0>] (bus_add_driver) from [<c0476a20>] (driver_register+0xac/0xf0)
  [<c0476a20>] (driver_register) from [<c0102dd4>] (do_one_initcall+0xb8/0x1f0)
  [<c0102dd4>] (do_one_initcall) from [<c0b010a0>] (kernel_init_freeable+0x294/0x2e0)
  [<c0b010a0>] (kernel_init_freeable) from [<c07e9eb8>] (kernel_init+0x8/0x10c)
  [<c07e9eb8>] (kernel_init) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
  Exception stack(0xd008bfb0 to 0xd008bff8)
  bfa0:                                     00000000 00000000 00000000 00000000
  bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
  bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
  ---[ end trace c0af40f9e2ed7cb4 ]---

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
[b.zolnierkie: enhance patch description a bit]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
frank-w pushed a commit that referenced this pull request Nov 5, 2018
[ Upstream commit d85536c ]

Add missing prepare/unprepare operations for fbi->clk,
this fixes following kernel warning:

  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:874 clk_core_enable+0x2c/0x1b0
  Enabling unprepared disp0_clk
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper Not tainted 4.18.0-rc8-00032-g02b43ddd4f21-dirty #25
  Hardware name: Marvell MMP2 (Device Tree Support)
  [<c010f7cc>] (unwind_backtrace) from [<c010cc6c>] (show_stack+0x10/0x14)
  [<c010cc6c>] (show_stack) from [<c011dab4>] (__warn+0xd8/0xf0)
  [<c011dab4>] (__warn) from [<c011db10>] (warn_slowpath_fmt+0x44/0x6c)
  [<c011db10>] (warn_slowpath_fmt) from [<c043898c>] (clk_core_enable+0x2c/0x1b0)
  [<c043898c>] (clk_core_enable) from [<c0439ec8>] (clk_core_enable_lock+0x18/0x2c)
  [<c0439ec8>] (clk_core_enable_lock) from [<c0436698>] (pxa168fb_probe+0x464/0x6ac)
  [<c0436698>] (pxa168fb_probe) from [<c04779a0>] (platform_drv_probe+0x48/0x94)
  [<c04779a0>] (platform_drv_probe) from [<c0475bec>] (driver_probe_device+0x328/0x470)
  [<c0475bec>] (driver_probe_device) from [<c0475de4>] (__driver_attach+0xb0/0x124)
  [<c0475de4>] (__driver_attach) from [<c0473c38>] (bus_for_each_dev+0x64/0xa0)
  [<c0473c38>] (bus_for_each_dev) from [<c0474ee0>] (bus_add_driver+0x1b8/0x230)
  [<c0474ee0>] (bus_add_driver) from [<c0476a20>] (driver_register+0xac/0xf0)
  [<c0476a20>] (driver_register) from [<c0102dd4>] (do_one_initcall+0xb8/0x1f0)
  [<c0102dd4>] (do_one_initcall) from [<c0b010a0>] (kernel_init_freeable+0x294/0x2e0)
  [<c0b010a0>] (kernel_init_freeable) from [<c07e9eb8>] (kernel_init+0x8/0x10c)
  [<c07e9eb8>] (kernel_init) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
  Exception stack(0xd008bfb0 to 0xd008bff8)
  bfa0:                                     00000000 00000000 00000000 00000000
  bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
  bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
  ---[ end trace c0af40f9e2ed7cb4 ]---

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
[b.zolnierkie: enhance patch description a bit]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Nov 5, 2018
[ Upstream commit d85536c ]

Add missing prepare/unprepare operations for fbi->clk,
this fixes following kernel warning:

  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:874 clk_core_enable+0x2c/0x1b0
  Enabling unprepared disp0_clk
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper Not tainted 4.18.0-rc8-00032-g02b43ddd4f21-dirty #25
  Hardware name: Marvell MMP2 (Device Tree Support)
  [<c010f7cc>] (unwind_backtrace) from [<c010cc6c>] (show_stack+0x10/0x14)
  [<c010cc6c>] (show_stack) from [<c011dab4>] (__warn+0xd8/0xf0)
  [<c011dab4>] (__warn) from [<c011db10>] (warn_slowpath_fmt+0x44/0x6c)
  [<c011db10>] (warn_slowpath_fmt) from [<c043898c>] (clk_core_enable+0x2c/0x1b0)
  [<c043898c>] (clk_core_enable) from [<c0439ec8>] (clk_core_enable_lock+0x18/0x2c)
  [<c0439ec8>] (clk_core_enable_lock) from [<c0436698>] (pxa168fb_probe+0x464/0x6ac)
  [<c0436698>] (pxa168fb_probe) from [<c04779a0>] (platform_drv_probe+0x48/0x94)
  [<c04779a0>] (platform_drv_probe) from [<c0475bec>] (driver_probe_device+0x328/0x470)
  [<c0475bec>] (driver_probe_device) from [<c0475de4>] (__driver_attach+0xb0/0x124)
  [<c0475de4>] (__driver_attach) from [<c0473c38>] (bus_for_each_dev+0x64/0xa0)
  [<c0473c38>] (bus_for_each_dev) from [<c0474ee0>] (bus_add_driver+0x1b8/0x230)
  [<c0474ee0>] (bus_add_driver) from [<c0476a20>] (driver_register+0xac/0xf0)
  [<c0476a20>] (driver_register) from [<c0102dd4>] (do_one_initcall+0xb8/0x1f0)
  [<c0102dd4>] (do_one_initcall) from [<c0b010a0>] (kernel_init_freeable+0x294/0x2e0)
  [<c0b010a0>] (kernel_init_freeable) from [<c07e9eb8>] (kernel_init+0x8/0x10c)
  [<c07e9eb8>] (kernel_init) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
  Exception stack(0xd008bfb0 to 0xd008bff8)
  bfa0:                                     00000000 00000000 00000000 00000000
  bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
  bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
  ---[ end trace c0af40f9e2ed7cb4 ]---

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
[b.zolnierkie: enhance patch description a bit]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Dec 17, 2018
Increase kasan instrumented kernel stack size from 32k to 64k. Other
architectures seems to get away with just doubling kernel stack size under
kasan, but on s390 this appears to be not enough due to bigger frame size.
The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE
vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting
stack overflow is fs sync on xfs filesystem:

 #0 [9a0681e8]  704 bytes  check_usage at 34b1fc
 #1 [9a0684a8]  432 bytes  check_usage at 34c710
 #2 [9a068658]  1048 bytes  validate_chain at 35044a
 #3 [9a068a70]  312 bytes  __lock_acquire at 3559fe
 #4 [9a068ba8]  440 bytes  lock_acquire at 3576ee
 #5 [9a068d60]  104 bytes  _raw_spin_lock at 21b44e0
 #6 [9a068dc8]  1992 bytes  enqueue_entity at 2dbf72
 #7 [9a069590]  1496 bytes  enqueue_task_fair at 2df5f0
 #8 [9a069b68]  64 bytes  ttwu_do_activate at 28f438
 #9 [9a069ba8]  552 bytes  try_to_wake_up at 298c4c
 #10 [9a069dd0]  168 bytes  wake_up_worker at 23f97c
 #11 [9a069e78]  200 bytes  insert_work at 23fc2e
 #12 [9a069f40]  648 bytes  __queue_work at 2487c0
 #13 [9a06a1c8]  200 bytes  __queue_delayed_work at 24db28
 #14 [9a06a290]  248 bytes  mod_delayed_work_on at 24de84
 #15 [9a06a388]  24 bytes  kblockd_mod_delayed_work_on at 153e2a0
 #16 [9a06a3a0]  288 bytes  __blk_mq_delay_run_hw_queue at 158168c
 #17 [9a06a4c0]  192 bytes  blk_mq_run_hw_queue at 1581a3c
 #18 [9a06a580]  184 bytes  blk_mq_sched_insert_requests at 15a2192
 #19 [9a06a638]  1024 bytes  blk_mq_flush_plug_list at 1590f3a
 #20 [9a06aa38]  704 bytes  blk_flush_plug_list at 1555028
 #21 [9a06acf8]  320 bytes  schedule at 219e476
 #22 [9a06ae38]  760 bytes  schedule_timeout at 21b0aac
 #23 [9a06b130]  408 bytes  wait_for_common at 21a1706
 #24 [9a06b2c8]  360 bytes  xfs_buf_iowait at fa1540
 #25 [9a06b430]  256 bytes  __xfs_buf_submit at fadae6
 #26 [9a06b530]  264 bytes  xfs_buf_read_map at fae3f6
 #27 [9a06b638]  656 bytes  xfs_trans_read_buf_map at 10ac9a8
 #28 [9a06b8c8]  304 bytes  xfs_btree_kill_root at e72426
 #29 [9a06b9f8]  288 bytes  xfs_btree_lookup_get_block at e7bc5e
 #30 [9a06bb18]  624 bytes  xfs_btree_lookup at e7e1a6
 #31 [9a06bd88]  2664 bytes  xfs_alloc_ag_vextent_near at dfa070
 #32 [9a06c7f0]  144 bytes  xfs_alloc_ag_vextent at dff3ca
 #33 [9a06c880]  1128 bytes  xfs_alloc_vextent at e05fce
 #34 [9a06cce8]  584 bytes  xfs_bmap_btalloc at e58342
 #35 [9a06cf30]  1336 bytes  xfs_bmapi_write at e618de
 #36 [9a06d468]  776 bytes  xfs_iomap_write_allocate at ff678e
 #37 [9a06d770]  720 bytes  xfs_map_blocks at f82af8
 #38 [9a06da40]  928 bytes  xfs_writepage_map at f83cd6
 #39 [9a06dde0]  320 bytes  xfs_do_writepage at f85872
 #40 [9a06df20]  1320 bytes  write_cache_pages at 73dfe8
 #41 [9a06e448]  208 bytes  xfs_vm_writepages at f7f892
 #42 [9a06e518]  88 bytes  do_writepages at 73fe6a
 #43 [9a06e570]  872 bytes  __writeback_single_inode at a20cb6
 #44 [9a06e8d8]  664 bytes  writeback_sb_inodes at a23be2
 #45 [9a06eb70]  296 bytes  __writeback_inodes_wb at a242e0
 #46 [9a06ec98]  928 bytes  wb_writeback at a2500e
 #47 [9a06f038]  848 bytes  wb_do_writeback at a260ae
 #48 [9a06f388]  536 bytes  wb_workfn at a28228
 #49 [9a06f5a0]  1088 bytes  process_one_work at 24a234
 #50 [9a06f9e0]  1120 bytes  worker_thread at 24ba26
 #51 [9a06fe40]  104 bytes  kthread at 26545a
 #52 [9a06fea8]             kernel_thread_starter at 21b6b62

To be able to increase the stack size to 64k reuse LLILL instruction
in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE
(65192) value as unsigned.

Reported-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
frank-w pushed a commit that referenced this pull request Dec 25, 2018
create_ctx can be called from atomic context, hence use
GFP_ATOMIC instead of GFP_KERNEL.

[  395.962599] BUG: sleeping function called from invalid context at mm/slab.h:421
[  395.979896] in_atomic(): 1, irqs_disabled(): 0, pid: 16254, name: openssl
[  395.996564] 2 locks held by openssl/16254:
[  396.010492]  #0: 00000000347acb52 (sk_lock-AF_INET){+.+.}, at: do_tcp_setsockopt.isra.44+0x13b/0x9a0
[  396.029838]  #1: 000000006c9552b5 (device_spinlock){+...}, at: tls_init+0x1d/0x280
[  396.047675] CPU: 5 PID: 16254 Comm: openssl Tainted: G           O      4.20.0-rc6+ #25
[  396.066019] Hardware name: Supermicro X10SRA-F/X10SRA-F, BIOS 2.0c 09/25/2017
[  396.083537] Call Trace:
[  396.096265]  dump_stack+0x5e/0x8b
[  396.109876]  ___might_sleep+0x216/0x250
[  396.123940]  kmem_cache_alloc_trace+0x1b0/0x240
[  396.138800]  create_ctx+0x1f/0x60
[  396.152504]  tls_init+0xbd/0x280
[  396.166135]  tcp_set_ulp+0x191/0x2d0
[  396.180035]  ? tcp_set_ulp+0x2c/0x2d0
[  396.193960]  do_tcp_setsockopt.isra.44+0x148/0x9a0
[  396.209013]  __sys_setsockopt+0x7c/0xe0
[  396.223054]  __x64_sys_setsockopt+0x20/0x30
[  396.237378]  do_syscall_64+0x4a/0x180
[  396.251200]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: df9d4a1 ("net/tls: sleeping function from invalid context")
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
frank-w pushed a commit that referenced this pull request Jan 9, 2019
[ Upstream commit c6ec179 ]

create_ctx can be called from atomic context, hence use
GFP_ATOMIC instead of GFP_KERNEL.

[  395.962599] BUG: sleeping function called from invalid context at mm/slab.h:421
[  395.979896] in_atomic(): 1, irqs_disabled(): 0, pid: 16254, name: openssl
[  395.996564] 2 locks held by openssl/16254:
[  396.010492]  #0: 00000000347acb52 (sk_lock-AF_INET){+.+.}, at: do_tcp_setsockopt.isra.44+0x13b/0x9a0
[  396.029838]  #1: 000000006c9552b5 (device_spinlock){+...}, at: tls_init+0x1d/0x280
[  396.047675] CPU: 5 PID: 16254 Comm: openssl Tainted: G           O      4.20.0-rc6+ #25
[  396.066019] Hardware name: Supermicro X10SRA-F/X10SRA-F, BIOS 2.0c 09/25/2017
[  396.083537] Call Trace:
[  396.096265]  dump_stack+0x5e/0x8b
[  396.109876]  ___might_sleep+0x216/0x250
[  396.123940]  kmem_cache_alloc_trace+0x1b0/0x240
[  396.138800]  create_ctx+0x1f/0x60
[  396.152504]  tls_init+0xbd/0x280
[  396.166135]  tcp_set_ulp+0x191/0x2d0
[  396.180035]  ? tcp_set_ulp+0x2c/0x2d0
[  396.193960]  do_tcp_setsockopt.isra.44+0x148/0x9a0
[  396.209013]  __sys_setsockopt+0x7c/0xe0
[  396.223054]  __x64_sys_setsockopt+0x20/0x30
[  396.237378]  do_syscall_64+0x4a/0x180
[  396.251200]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: df9d4a1 ("net/tls: sleeping function from invalid context")
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Feb 2, 2019
…s while handle_mm_fault

do_page_fault() forgot to relinquish mmap_sem if a signal came while
handling handle_mm_fault() - due to say a ctl+c or oom etc.
This would later cause a deadlock by acquiring it twice.

This came to light when running libc testsuite tst-tls3-malloc test but
is likely also the cause for prior seen LTP failures. Using lockdep
clearly showed what the issue was.

| # while true; do ./tst-tls3-malloc ; done
| Didn't expect signal from child: got `Segmentation fault'
| ^C
| ============================================
| WARNING: possible recursive locking detected
| 4.17.0+ #25 Not tainted
| --------------------------------------------
| tst-tls3-malloc/510 is trying to acquire lock:
| 606c7728 (&mm->mmap_sem){++++}, at: __might_fault+0x28/0x5c
|
|but task is already holding lock:
|606c7728 (&mm->mmap_sem){++++}, at: do_page_fault+0x9c/0x2a0
|
| other info that might help us debug this:
|  Possible unsafe locking scenario:
|
|       CPU0
|       ----
|  lock(&mm->mmap_sem);
|  lock(&mm->mmap_sem);
|
| *** DEADLOCK ***
|

------------------------------------------------------------
What the change does is not obvious (note to myself)

prior code was

| do_page_fault
|
|   down_read()		<-- lock taken
|   handle_mm_fault	<-- signal pending as this runs
|   if fatal_signal_pending
|       if VM_FAULT_ERROR
|           up_read
|       if user_mode
|          return	<-- lock still held, this was the BUG

New code

| do_page_fault
|
|   down_read()		<-- lock taken
|   handle_mm_fault	<-- signal pending as this runs
|   if fatal_signal_pending
|       if VM_FAULT_RETRY
|          return       <-- not same case as above, but still OK since
|                           core mm already relinq lock for FAULT_RETRY
|    ...
|
|   < Now falls through for bug case above >
|
|   up_read()		<-- lock relinquished

Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
frank-w pushed a commit that referenced this pull request Mar 4, 2019
Eric Biggers reported:
> The following commit, which went into v4.20, introduced undefined behavior when
> sys_rt_sigqueueinfo() is called with sig=0:
>
> commit 4ce5f9c
> Author: Eric W. Biederman <ebiederm@xmission.com>
> Date:   Tue Sep 25 12:59:31 2018 +0200
>
>     signal: Use a smaller struct siginfo in the kernel
>
> In sig_specific_sicodes(), used from known_siginfo_layout(), the expression
> '1ULL << ((sig)-1)' is undefined as it evaluates to 1ULL << 4294967295.
>
> Reproducer:
>
> #include <signal.h>
> #include <sys/syscall.h>
> #include <unistd.h>
>
> int main(void)
> {
> 	siginfo_t si = { .si_code = 1 };
> 	syscall(__NR_rt_sigqueueinfo, 0, 0, &si);
> }
>
> UBSAN report for v5.0-rc1:
>
> UBSAN: Undefined behaviour in kernel/signal.c:2946:7
> shift exponent 4294967295 is too large for 64-bit type 'long unsigned int'
> CPU: 2 PID: 346 Comm: syz_signal Not tainted 5.0.0-rc1 #25
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
> Call Trace:
>  __dump_stack lib/dump_stack.c:77 [inline]
>  dump_stack+0x70/0xa5 lib/dump_stack.c:113
>  ubsan_epilogue+0xd/0x40 lib/ubsan.c:159
>  __ubsan_handle_shift_out_of_bounds+0x12c/0x170 lib/ubsan.c:425
>  known_siginfo_layout+0xae/0xe0 kernel/signal.c:2946
>  post_copy_siginfo_from_user kernel/signal.c:3009 [inline]
>  __copy_siginfo_from_user+0x35/0x60 kernel/signal.c:3035
>  __do_sys_rt_sigqueueinfo kernel/signal.c:3553 [inline]
>  __se_sys_rt_sigqueueinfo kernel/signal.c:3549 [inline]
>  __x64_sys_rt_sigqueueinfo+0x31/0x70 kernel/signal.c:3549
>  do_syscall_64+0x4c/0x1b0 arch/x86/entry/common.c:290
>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x433639
> Code: c4 18 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 27 00 00 c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007fffcb289fc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000081
> RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000433639
> RDX: 00007fffcb289fd0 RSI: 0000000000000000 RDI: 0000000000000000
> RBP: 00000000006b2018 R08: 000000000000004d R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401560
> R13: 00000000004015f0 R14: 0000000000000000 R15: 0000000000000000

I have looked at the other callers of siginmask and they all appear to
in locations where sig can not be zero.

I have looked at the code generation of adding an extra test against
zero and gcc was able with a simple decrement instruction to combine
the two tests together. So the at most adding this test cost a single
cpu cycle.  In practice that decrement instruction was already present
as part of the mask comparison, so the only change was when the
instruction was executed.

So given that it is cheap, and obviously correct to update siginmask
to verify the signal is not zero.  Fix this issue there to avoid any
future problems.

Reported-by: Eric Biggers <ebiggers@kernel.org>
Fixes: 4ce5f9c ("signal: Use a smaller struct siginfo in the kernel")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
frank-w pushed a commit that referenced this pull request Mar 20, 2019
[ Upstream commit ee17e5d ]

Eric Biggers reported:
> The following commit, which went into v4.20, introduced undefined behavior when
> sys_rt_sigqueueinfo() is called with sig=0:
>
> commit 4ce5f9c
> Author: Eric W. Biederman <ebiederm@xmission.com>
> Date:   Tue Sep 25 12:59:31 2018 +0200
>
>     signal: Use a smaller struct siginfo in the kernel
>
> In sig_specific_sicodes(), used from known_siginfo_layout(), the expression
> '1ULL << ((sig)-1)' is undefined as it evaluates to 1ULL << 4294967295.
>
> Reproducer:
>
> #include <signal.h>
> #include <sys/syscall.h>
> #include <unistd.h>
>
> int main(void)
> {
> 	siginfo_t si = { .si_code = 1 };
> 	syscall(__NR_rt_sigqueueinfo, 0, 0, &si);
> }
>
> UBSAN report for v5.0-rc1:
>
> UBSAN: Undefined behaviour in kernel/signal.c:2946:7
> shift exponent 4294967295 is too large for 64-bit type 'long unsigned int'
> CPU: 2 PID: 346 Comm: syz_signal Not tainted 5.0.0-rc1 #25
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
> Call Trace:
>  __dump_stack lib/dump_stack.c:77 [inline]
>  dump_stack+0x70/0xa5 lib/dump_stack.c:113
>  ubsan_epilogue+0xd/0x40 lib/ubsan.c:159
>  __ubsan_handle_shift_out_of_bounds+0x12c/0x170 lib/ubsan.c:425
>  known_siginfo_layout+0xae/0xe0 kernel/signal.c:2946
>  post_copy_siginfo_from_user kernel/signal.c:3009 [inline]
>  __copy_siginfo_from_user+0x35/0x60 kernel/signal.c:3035
>  __do_sys_rt_sigqueueinfo kernel/signal.c:3553 [inline]
>  __se_sys_rt_sigqueueinfo kernel/signal.c:3549 [inline]
>  __x64_sys_rt_sigqueueinfo+0x31/0x70 kernel/signal.c:3549
>  do_syscall_64+0x4c/0x1b0 arch/x86/entry/common.c:290
>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x433639
> Code: c4 18 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 27 00 00 c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007fffcb289fc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000081
> RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000433639
> RDX: 00007fffcb289fd0 RSI: 0000000000000000 RDI: 0000000000000000
> RBP: 00000000006b2018 R08: 000000000000004d R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401560
> R13: 00000000004015f0 R14: 0000000000000000 R15: 0000000000000000

I have looked at the other callers of siginmask and they all appear to
in locations where sig can not be zero.

I have looked at the code generation of adding an extra test against
zero and gcc was able with a simple decrement instruction to combine
the two tests together. So the at most adding this test cost a single
cpu cycle.  In practice that decrement instruction was already present
as part of the mask comparison, so the only change was when the
instruction was executed.

So given that it is cheap, and obviously correct to update siginmask
to verify the signal is not zero.  Fix this issue there to avoid any
future problems.

Reported-by: Eric Biggers <ebiggers@kernel.org>
Fixes: 4ce5f9c ("signal: Use a smaller struct siginfo in the kernel")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Aug 2, 2019
commit d454854 upstream.

KASAN report this:

BUG: unable to handle kernel paging request at ffffffffa0097000
PGD 3870067 P4D 3870067 PUD 3871063 PMD 2326e2067 PTE 0
Oops: 0000 [#1
CPU: 0 PID: 5340 Comm: modprobe Not tainted 5.1.0-rc7+ #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:__list_add_valid+0x10/0x70
Code: c3 48 8b 06 55 48 89 e5 5d 48 39 07 0f 94 c0 0f b6 c0 c3 90 90 90 90 90 90 90 55 48 89 d0 48 8b 52 08 48 89 e5 48 39 f2 75 19 <48> 8b 32 48 39 f0 75 3a

RSP: 0018:ffffc90000e23c68 EFLAGS: 00010246
RAX: ffffffffa00ad000 RBX: ffffffffa009d000 RCX: 0000000000000000
RDX: ffffffffa0097000 RSI: ffffffffa0097000 RDI: ffffffffa009d000
RBP: ffffc90000e23c68 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffa0097000
R13: ffff888231797180 R14: 0000000000000000 R15: ffffc90000e23e78
FS:  00007fb215285540(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffa0097000 CR3: 000000022f144000 CR4: 00000000000006f0
Call Trace:
 v9fs_register_trans+0x2f/0x60 [9pnet
 ? 0xffffffffa0087000
 p9_virtio_init+0x25/0x1000 [9pnet_virtio
 do_one_initcall+0x6c/0x3cc
 ? kmem_cache_alloc_trace+0x248/0x3b0
 do_init_module+0x5b/0x1f1
 load_module+0x1db1/0x2690
 ? m_show+0x1d0/0x1d0
 __do_sys_finit_module+0xc5/0xd0
 __x64_sys_finit_module+0x15/0x20
 do_syscall_64+0x6b/0x1d0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fb214d8e839
Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01

RSP: 002b:00007ffc96554278 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 000055e67eed2aa0 RCX: 00007fb214d8e839
RDX: 0000000000000000 RSI: 000055e67ce95c2e RDI: 0000000000000003
RBP: 000055e67ce95c2e R08: 0000000000000000 R09: 000055e67eed2aa0
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
R13: 000055e67eeda500 R14: 0000000000040000 R15: 000055e67eed2aa0
Modules linked in: 9pnet_virtio(+) 9pnet gre rfkill vmw_vsock_virtio_transport_common vsock [last unloaded: 9pnet_virtio
CR2: ffffffffa0097000
---[ end trace 4a52bb13ff07b761

If register_virtio_driver() fails in p9_virtio_init,
we should call v9fs_unregister_trans() to do cleanup.

Link: http://lkml.kernel.org/r/20190430115942.41840-1-yuehaibing@huawei.com
Cc: stable@vger.kernel.org
Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: b530cc7 ("9p: add virtio transport")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Aug 5, 2019
commit d454854 upstream.

KASAN report this:

BUG: unable to handle kernel paging request at ffffffffa0097000
PGD 3870067 P4D 3870067 PUD 3871063 PMD 2326e2067 PTE 0
Oops: 0000 [#1
CPU: 0 PID: 5340 Comm: modprobe Not tainted 5.1.0-rc7+ #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:__list_add_valid+0x10/0x70
Code: c3 48 8b 06 55 48 89 e5 5d 48 39 07 0f 94 c0 0f b6 c0 c3 90 90 90 90 90 90 90 55 48 89 d0 48 8b 52 08 48 89 e5 48 39 f2 75 19 <48> 8b 32 48 39 f0 75 3a

RSP: 0018:ffffc90000e23c68 EFLAGS: 00010246
RAX: ffffffffa00ad000 RBX: ffffffffa009d000 RCX: 0000000000000000
RDX: ffffffffa0097000 RSI: ffffffffa0097000 RDI: ffffffffa009d000
RBP: ffffc90000e23c68 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffa0097000
R13: ffff888231797180 R14: 0000000000000000 R15: ffffc90000e23e78
FS:  00007fb215285540(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffa0097000 CR3: 000000022f144000 CR4: 00000000000006f0
Call Trace:
 v9fs_register_trans+0x2f/0x60 [9pnet
 ? 0xffffffffa0087000
 p9_virtio_init+0x25/0x1000 [9pnet_virtio
 do_one_initcall+0x6c/0x3cc
 ? kmem_cache_alloc_trace+0x248/0x3b0
 do_init_module+0x5b/0x1f1
 load_module+0x1db1/0x2690
 ? m_show+0x1d0/0x1d0
 __do_sys_finit_module+0xc5/0xd0
 __x64_sys_finit_module+0x15/0x20
 do_syscall_64+0x6b/0x1d0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fb214d8e839
Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01

RSP: 002b:00007ffc96554278 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 000055e67eed2aa0 RCX: 00007fb214d8e839
RDX: 0000000000000000 RSI: 000055e67ce95c2e RDI: 0000000000000003
RBP: 000055e67ce95c2e R08: 0000000000000000 R09: 000055e67eed2aa0
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
R13: 000055e67eeda500 R14: 0000000000040000 R15: 000055e67eed2aa0
Modules linked in: 9pnet_virtio(+) 9pnet gre rfkill vmw_vsock_virtio_transport_common vsock [last unloaded: 9pnet_virtio
CR2: ffffffffa0097000
---[ end trace 4a52bb13ff07b761

If register_virtio_driver() fails in p9_virtio_init,
we should call v9fs_unregister_trans() to do cleanup.

Link: http://lkml.kernel.org/r/20190430115942.41840-1-yuehaibing@huawei.com
Cc: stable@vger.kernel.org
Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: b530cc7 ("9p: add virtio transport")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Aug 10, 2019
commit d454854 upstream.

KASAN report this:

BUG: unable to handle kernel paging request at ffffffffa0097000
PGD 3870067 P4D 3870067 PUD 3871063 PMD 2326e2067 PTE 0
Oops: 0000 [#1
CPU: 0 PID: 5340 Comm: modprobe Not tainted 5.1.0-rc7+ #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:__list_add_valid+0x10/0x70
Code: c3 48 8b 06 55 48 89 e5 5d 48 39 07 0f 94 c0 0f b6 c0 c3 90 90 90 90 90 90 90 55 48 89 d0 48 8b 52 08 48 89 e5 48 39 f2 75 19 <48> 8b 32 48 39 f0 75 3a

RSP: 0018:ffffc90000e23c68 EFLAGS: 00010246
RAX: ffffffffa00ad000 RBX: ffffffffa009d000 RCX: 0000000000000000
RDX: ffffffffa0097000 RSI: ffffffffa0097000 RDI: ffffffffa009d000
RBP: ffffc90000e23c68 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffa0097000
R13: ffff888231797180 R14: 0000000000000000 R15: ffffc90000e23e78
FS:  00007fb215285540(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffa0097000 CR3: 000000022f144000 CR4: 00000000000006f0
Call Trace:
 v9fs_register_trans+0x2f/0x60 [9pnet
 ? 0xffffffffa0087000
 p9_virtio_init+0x25/0x1000 [9pnet_virtio
 do_one_initcall+0x6c/0x3cc
 ? kmem_cache_alloc_trace+0x248/0x3b0
 do_init_module+0x5b/0x1f1
 load_module+0x1db1/0x2690
 ? m_show+0x1d0/0x1d0
 __do_sys_finit_module+0xc5/0xd0
 __x64_sys_finit_module+0x15/0x20
 do_syscall_64+0x6b/0x1d0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fb214d8e839
Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01

RSP: 002b:00007ffc96554278 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 000055e67eed2aa0 RCX: 00007fb214d8e839
RDX: 0000000000000000 RSI: 000055e67ce95c2e RDI: 0000000000000003
RBP: 000055e67ce95c2e R08: 0000000000000000 R09: 000055e67eed2aa0
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
R13: 000055e67eeda500 R14: 0000000000040000 R15: 000055e67eed2aa0
Modules linked in: 9pnet_virtio(+) 9pnet gre rfkill vmw_vsock_virtio_transport_common vsock [last unloaded: 9pnet_virtio
CR2: ffffffffa0097000
---[ end trace 4a52bb13ff07b761

If register_virtio_driver() fails in p9_virtio_init,
we should call v9fs_unregister_trans() to do cleanup.

Link: http://lkml.kernel.org/r/20190430115942.41840-1-yuehaibing@huawei.com
Cc: stable@vger.kernel.org
Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: b530cc7 ("9p: add virtio transport")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Sep 27, 2019
…s while handle_mm_fault

[ Upstream commit 4d44745 ]

do_page_fault() forgot to relinquish mmap_sem if a signal came while
handling handle_mm_fault() - due to say a ctl+c or oom etc.
This would later cause a deadlock by acquiring it twice.

This came to light when running libc testsuite tst-tls3-malloc test but
is likely also the cause for prior seen LTP failures. Using lockdep
clearly showed what the issue was.

| # while true; do ./tst-tls3-malloc ; done
| Didn't expect signal from child: got `Segmentation fault'
| ^C
| ============================================
| WARNING: possible recursive locking detected
| 4.17.0+ #25 Not tainted
| --------------------------------------------
| tst-tls3-malloc/510 is trying to acquire lock:
| 606c7728 (&mm->mmap_sem){++++}, at: __might_fault+0x28/0x5c
|
|but task is already holding lock:
|606c7728 (&mm->mmap_sem){++++}, at: do_page_fault+0x9c/0x2a0
|
| other info that might help us debug this:
|  Possible unsafe locking scenario:
|
|       CPU0
|       ----
|  lock(&mm->mmap_sem);
|  lock(&mm->mmap_sem);
|
| *** DEADLOCK ***
|

------------------------------------------------------------
What the change does is not obvious (note to myself)

prior code was

| do_page_fault
|
|   down_read()		<-- lock taken
|   handle_mm_fault	<-- signal pending as this runs
|   if fatal_signal_pending
|       if VM_FAULT_ERROR
|           up_read
|       if user_mode
|          return	<-- lock still held, this was the BUG

New code

| do_page_fault
|
|   down_read()		<-- lock taken
|   handle_mm_fault	<-- signal pending as this runs
|   if fatal_signal_pending
|       if VM_FAULT_RETRY
|          return       <-- not same case as above, but still OK since
|                           core mm already relinq lock for FAULT_RETRY
|    ...
|
|   < Now falls through for bug case above >
|
|   up_read()		<-- lock relinquished

Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Sep 27, 2019
[ Upstream commit d85536c ]

Add missing prepare/unprepare operations for fbi->clk,
this fixes following kernel warning:

  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:874 clk_core_enable+0x2c/0x1b0
  Enabling unprepared disp0_clk
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper Not tainted 4.18.0-rc8-00032-g02b43ddd4f21-dirty #25
  Hardware name: Marvell MMP2 (Device Tree Support)
  [<c010f7cc>] (unwind_backtrace) from [<c010cc6c>] (show_stack+0x10/0x14)
  [<c010cc6c>] (show_stack) from [<c011dab4>] (__warn+0xd8/0xf0)
  [<c011dab4>] (__warn) from [<c011db10>] (warn_slowpath_fmt+0x44/0x6c)
  [<c011db10>] (warn_slowpath_fmt) from [<c043898c>] (clk_core_enable+0x2c/0x1b0)
  [<c043898c>] (clk_core_enable) from [<c0439ec8>] (clk_core_enable_lock+0x18/0x2c)
  [<c0439ec8>] (clk_core_enable_lock) from [<c0436698>] (pxa168fb_probe+0x464/0x6ac)
  [<c0436698>] (pxa168fb_probe) from [<c04779a0>] (platform_drv_probe+0x48/0x94)
  [<c04779a0>] (platform_drv_probe) from [<c0475bec>] (driver_probe_device+0x328/0x470)
  [<c0475bec>] (driver_probe_device) from [<c0475de4>] (__driver_attach+0xb0/0x124)
  [<c0475de4>] (__driver_attach) from [<c0473c38>] (bus_for_each_dev+0x64/0xa0)
  [<c0473c38>] (bus_for_each_dev) from [<c0474ee0>] (bus_add_driver+0x1b8/0x230)
  [<c0474ee0>] (bus_add_driver) from [<c0476a20>] (driver_register+0xac/0xf0)
  [<c0476a20>] (driver_register) from [<c0102dd4>] (do_one_initcall+0xb8/0x1f0)
  [<c0102dd4>] (do_one_initcall) from [<c0b010a0>] (kernel_init_freeable+0x294/0x2e0)
  [<c0b010a0>] (kernel_init_freeable) from [<c07e9eb8>] (kernel_init+0x8/0x10c)
  [<c07e9eb8>] (kernel_init) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
  Exception stack(0xd008bfb0 to 0xd008bff8)
  bfa0:                                     00000000 00000000 00000000 00000000
  bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
  bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
  ---[ end trace c0af40f9e2ed7cb4 ]---

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
[b.zolnierkie: enhance patch description a bit]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Oct 6, 2019
[ Upstream commit 46e4a26 ]

syzbot reports an error on flush_request_modules() for the second device.
This workqueue was never initialised so simply remove the offending line.

usb 1-1: USB disconnect, device number 2
em28xx 1-1:1.153: Disconnecting em28xx #1
------------[ cut here ]------------
WARNING: CPU: 0 PID: 12 at kernel/workqueue.c:3031
__flush_work.cold+0x2c/0x36 kernel/workqueue.c:3031
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.3.0-rc2+ #25
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0xca/0x13e lib/dump_stack.c:113
  panic+0x2a3/0x6da kernel/panic.c:219
  __warn.cold+0x20/0x4a kernel/panic.c:576
  report_bug+0x262/0x2a0 lib/bug.c:186
  fixup_bug arch/x86/kernel/traps.c:179 [inline]
  fixup_bug arch/x86/kernel/traps.c:174 [inline]
  do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:272
  do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:291
  invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1026
RIP: 0010:__flush_work.cold+0x2c/0x36 kernel/workqueue.c:3031
Code: 9a 22 00 48 c7 c7 20 e4 c5 85 e8 d9 3a 0d 00 0f 0b 45 31 e4 e9 98 86
ff ff e8 51 9a 22 00 48 c7 c7 20 e4 c5 85 e8 be 3a 0d 00 <0f> 0b 45 31 e4
e9 7d 86 ff ff e8 36 9a 22 00 48 c7 c7 20 e4 c5 85
RSP: 0018:ffff8881da20f720 EFLAGS: 00010286
RAX: 0000000000000024 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8128a0fd RDI: ffffed103b441ed6
RBP: ffff8881da20f888 R08: 0000000000000024 R09: fffffbfff11acd9a
R10: fffffbfff11acd99 R11: ffffffff88d66ccf R12: 0000000000000000
R13: 0000000000000001 R14: ffff8881c6685df8 R15: ffff8881d2a85b78
  flush_request_modules drivers/media/usb/em28xx/em28xx-cards.c:3325 [inline]
  em28xx_usb_disconnect.cold+0x280/0x2a6
drivers/media/usb/em28xx/em28xx-cards.c:4023
  usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
  __device_release_driver drivers/base/dd.c:1120 [inline]
  device_release_driver_internal+0x404/0x4c0 drivers/base/dd.c:1151
  bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:556
  device_del+0x420/0xb10 drivers/base/core.c:2288
  usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
  usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199
  hub_port_connect drivers/usb/core/hub.c:4949 [inline]
  hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
  port_event drivers/usb/core/hub.c:5359 [inline]
  hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441
  process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
  process_scheduled_works kernel/workqueue.c:2331 [inline]
  worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
  kthread+0x318/0x420 kernel/kthread.c:255
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..

Fixes: be7fd3c ("media: em28xx: Hauppauge DualHD second tuner functionality)
Reviewed-by: Ezequiel Garcia <ezequiel@collabora.com>
Reviewed-by: Brad Love <brad@nextdimension.cc>
Reported-by: syzbot+b7f57261c521087d89bb@syzkaller.appspotmail.com
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Nov 10, 2019
The RCU lock is insufficient to protect the radix tree iteration as
a deletion from the tree can occur before we take the spinlock to
tag the entry.  In 4.19, this has manifested as a bug with the following
trace:

kernel BUG at lib/radix-tree.c:1429!
invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 7 PID: 6935 Comm: syz-executor.2 Not tainted 4.19.36 #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
RIP: 0010:radix_tree_tag_set+0x200/0x2f0 lib/radix-tree.c:1429
Code: 00 00 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 89 44 24 10 e8 a3 29 7e fe 48 8b 44 24 10 48 0f ab 03 e9 d2 fe ff ff e8 90 29 7e fe <0f> 0b 48 c7 c7 e0 5a 87 84 e8 f0 e7 08 ff 4c 89 ef e8 4a ff ac fe
RSP: 0018:ffff88837b13fb60 EFLAGS: 00010016
RAX: 0000000000040000 RBX: ffff8883c5515d58 RCX: ffffffff82cb2ef0
RDX: 0000000000000b72 RSI: ffffc90004cf2000 RDI: ffff8883c5515d98
RBP: ffff88837b13fb98 R08: ffffed106f627f7e R09: ffffed106f627f7e
R10: 0000000000000001 R11: ffffed106f627f7d R12: 0000000000000004
R13: ffffea000d7fea80 R14: 1ffff1106f627f6f R15: 0000000000000002
FS:  00007fa1b8df2700(0000) GS:ffff8883e2fc0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa1b8df1db8 CR3: 000000037d4d2001 CR4: 0000000000160ee0
Call Trace:
 memfd_tag_pins mm/memfd.c:51 [inline]
 memfd_wait_for_pins+0x2c5/0x12d0 mm/memfd.c:81
 memfd_add_seals mm/memfd.c:215 [inline]
 memfd_fcntl+0x33d/0x4a0 mm/memfd.c:247
 do_fcntl+0x589/0xeb0 fs/fcntl.c:421
 __do_sys_fcntl fs/fcntl.c:463 [inline]
 __se_sys_fcntl fs/fcntl.c:448 [inline]
 __x64_sys_fcntl+0x12d/0x180 fs/fcntl.c:448
 do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:293

The problem does not occur in mainline due to the XArray rewrite which
changed the locking to exclude modification of the tree during iteration.
At the time, nobody realised this was a bugfix.  Backport the locking
changes to stable.

Cc: stable@vger.kernel.org
Reported-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Nov 10, 2019
The RCU lock is insufficient to protect the radix tree iteration as
a deletion from the tree can occur before we take the spinlock to
tag the entry.  In 4.19, this has manifested as a bug with the following
trace:

kernel BUG at lib/radix-tree.c:1429!
invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 7 PID: 6935 Comm: syz-executor.2 Not tainted 4.19.36 #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
RIP: 0010:radix_tree_tag_set+0x200/0x2f0 lib/radix-tree.c:1429
Code: 00 00 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 89 44 24 10 e8 a3 29 7e fe 48 8b 44 24 10 48 0f ab 03 e9 d2 fe ff ff e8 90 29 7e fe <0f> 0b 48 c7 c7 e0 5a 87 84 e8 f0 e7 08 ff 4c 89 ef e8 4a ff ac fe
RSP: 0018:ffff88837b13fb60 EFLAGS: 00010016
RAX: 0000000000040000 RBX: ffff8883c5515d58 RCX: ffffffff82cb2ef0
RDX: 0000000000000b72 RSI: ffffc90004cf2000 RDI: ffff8883c5515d98
RBP: ffff88837b13fb98 R08: ffffed106f627f7e R09: ffffed106f627f7e
R10: 0000000000000001 R11: ffffed106f627f7d R12: 0000000000000004
R13: ffffea000d7fea80 R14: 1ffff1106f627f6f R15: 0000000000000002
FS:  00007fa1b8df2700(0000) GS:ffff8883e2fc0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa1b8df1db8 CR3: 000000037d4d2001 CR4: 0000000000160ee0
Call Trace:
 memfd_tag_pins mm/memfd.c:51 [inline]
 memfd_wait_for_pins+0x2c5/0x12d0 mm/memfd.c:81
 memfd_add_seals mm/memfd.c:215 [inline]
 memfd_fcntl+0x33d/0x4a0 mm/memfd.c:247
 do_fcntl+0x589/0xeb0 fs/fcntl.c:421
 __do_sys_fcntl fs/fcntl.c:463 [inline]
 __se_sys_fcntl fs/fcntl.c:448 [inline]
 __x64_sys_fcntl+0x12d/0x180 fs/fcntl.c:448
 do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:293

The problem does not occur in mainline due to the XArray rewrite which
changed the locking to exclude modification of the tree during iteration.
At the time, nobody realised this was a bugfix.  Backport the locking
changes to stable.

Cc: stable@vger.kernel.org
Reported-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Jan 8, 2020
In a case when a ptp chardev (like /dev/ptp0) is open but an underlying
device is removed, closing this file leads to a race. This reproduces
easily in a kvm virtual machine:

ts# cat openptp0.c
int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); }
ts# uname -r
5.5.0-rc3-46cf053e
ts# cat /proc/cmdline
... slub_debug=FZP
ts# modprobe ptp_kvm
ts# ./openptp0 &
[1] 670
opened /dev/ptp0, sleeping 10s...
ts# rmmod ptp_kvm
ts# ls /dev/ptp*
ls: cannot access '/dev/ptp*': No such file or directory
ts# ...woken up
[   48.010809] general protection fault: 0000 [#1] SMP
[   48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25
[   48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
[   48.016270] RIP: 0010:module_put.part.0+0x7/0x80
[   48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202
[   48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0
[   48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b
[   48.019470] ...                                              ^^^ a slub poison
[   48.023854] Call Trace:
[   48.024050]  __fput+0x21f/0x240
[   48.024288]  task_work_run+0x79/0x90
[   48.024555]  do_exit+0x2af/0xab0
[   48.024799]  ? vfs_write+0x16a/0x190
[   48.025082]  do_group_exit+0x35/0x90
[   48.025387]  __x64_sys_exit_group+0xf/0x10
[   48.025737]  do_syscall_64+0x3d/0x130
[   48.026056]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   48.026479] RIP: 0033:0x7f53b12082f6
[   48.026792] ...
[   48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm]
[   48.045001] Fixing recursive fault but reboot is needed!

This happens in:

static void __fput(struct file *file)
{   ...
    if (file->f_op->release)
        file->f_op->release(inode, file); <<< cdev is kfree'd here
    if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
             !(mode & FMODE_PATH))) {
        cdev_put(inode->i_cdev); <<< cdev fields are accessed here

Namely:

__fput()
  posix_clock_release()
    kref_put(&clk->kref, delete_clock) <<< the last reference
      delete_clock()
        delete_ptp_clock()
          kfree(ptp) <<< cdev is embedded in ptp
  cdev_put
    module_put(p->owner) <<< *p is kfree'd, bang!

Here cdev is embedded in posix_clock which is embedded in ptp_clock.
The race happens because ptp_clock's lifetime is controlled by two
refcounts: kref and cdev.kobj in posix_clock. This is wrong.

Make ptp_clock's sysfs device a parent of cdev with cdev_device_add()
created especially for such cases. This way the parent device with its
ptp_clock is not released until all references to the cdev are released.
This adds a requirement that an initialized but not exposed struct
device should be provided to posix_clock_register() by a caller instead
of a simple dev_t.

This approach was adopted from the commit 72139df ("watchdog: Fix
the race between the release of watchdog_core_data and cdev"). See
details of the implementation in the commit 233ed09 ("chardev: add
helper function to register char devs with a struct device").

Link: https://lore.kernel.org/linux-fsdevel/20191125125342.6189-1-vdronov@redhat.com/T/#u
Analyzed-by: Stephen Johnston <sjohnsto@redhat.com>
Analyzed-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
frank-w pushed a commit that referenced this pull request Jan 15, 2020
[ Upstream commit a33121e ]

In a case when a ptp chardev (like /dev/ptp0) is open but an underlying
device is removed, closing this file leads to a race. This reproduces
easily in a kvm virtual machine:

ts# cat openptp0.c
int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); }
ts# uname -r
5.5.0-rc3-46cf053e
ts# cat /proc/cmdline
... slub_debug=FZP
ts# modprobe ptp_kvm
ts# ./openptp0 &
[1] 670
opened /dev/ptp0, sleeping 10s...
ts# rmmod ptp_kvm
ts# ls /dev/ptp*
ls: cannot access '/dev/ptp*': No such file or directory
ts# ...woken up
[   48.010809] general protection fault: 0000 [#1] SMP
[   48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25
[   48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
[   48.016270] RIP: 0010:module_put.part.0+0x7/0x80
[   48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202
[   48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0
[   48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b
[   48.019470] ...                                              ^^^ a slub poison
[   48.023854] Call Trace:
[   48.024050]  __fput+0x21f/0x240
[   48.024288]  task_work_run+0x79/0x90
[   48.024555]  do_exit+0x2af/0xab0
[   48.024799]  ? vfs_write+0x16a/0x190
[   48.025082]  do_group_exit+0x35/0x90
[   48.025387]  __x64_sys_exit_group+0xf/0x10
[   48.025737]  do_syscall_64+0x3d/0x130
[   48.026056]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   48.026479] RIP: 0033:0x7f53b12082f6
[   48.026792] ...
[   48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm]
[   48.045001] Fixing recursive fault but reboot is needed!

This happens in:

static void __fput(struct file *file)
{   ...
    if (file->f_op->release)
        file->f_op->release(inode, file); <<< cdev is kfree'd here
    if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
             !(mode & FMODE_PATH))) {
        cdev_put(inode->i_cdev); <<< cdev fields are accessed here

Namely:

__fput()
  posix_clock_release()
    kref_put(&clk->kref, delete_clock) <<< the last reference
      delete_clock()
        delete_ptp_clock()
          kfree(ptp) <<< cdev is embedded in ptp
  cdev_put
    module_put(p->owner) <<< *p is kfree'd, bang!

Here cdev is embedded in posix_clock which is embedded in ptp_clock.
The race happens because ptp_clock's lifetime is controlled by two
refcounts: kref and cdev.kobj in posix_clock. This is wrong.

Make ptp_clock's sysfs device a parent of cdev with cdev_device_add()
created especially for such cases. This way the parent device with its
ptp_clock is not released until all references to the cdev are released.
This adds a requirement that an initialized but not exposed struct
device should be provided to posix_clock_register() by a caller instead
of a simple dev_t.

This approach was adopted from the commit 72139df ("watchdog: Fix
the race between the release of watchdog_core_data and cdev"). See
details of the implementation in the commit 233ed09 ("chardev: add
helper function to register char devs with a struct device").

Link: https://lore.kernel.org/linux-fsdevel/20191125125342.6189-1-vdronov@redhat.com/T/#u
Analyzed-by: Stephen Johnston <sjohnsto@redhat.com>
Analyzed-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Feb 2, 2020
[ Upstream commit a33121e ]

In a case when a ptp chardev (like /dev/ptp0) is open but an underlying
device is removed, closing this file leads to a race. This reproduces
easily in a kvm virtual machine:

ts# cat openptp0.c
int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); }
ts# uname -r
5.5.0-rc3-46cf053e
ts# cat /proc/cmdline
... slub_debug=FZP
ts# modprobe ptp_kvm
ts# ./openptp0 &
[1] 670
opened /dev/ptp0, sleeping 10s...
ts# rmmod ptp_kvm
ts# ls /dev/ptp*
ls: cannot access '/dev/ptp*': No such file or directory
ts# ...woken up
[   48.010809] general protection fault: 0000 [#1] SMP
[   48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25
[   48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
[   48.016270] RIP: 0010:module_put.part.0+0x7/0x80
[   48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202
[   48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0
[   48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b
[   48.019470] ...                                              ^^^ a slub poison
[   48.023854] Call Trace:
[   48.024050]  __fput+0x21f/0x240
[   48.024288]  task_work_run+0x79/0x90
[   48.024555]  do_exit+0x2af/0xab0
[   48.024799]  ? vfs_write+0x16a/0x190
[   48.025082]  do_group_exit+0x35/0x90
[   48.025387]  __x64_sys_exit_group+0xf/0x10
[   48.025737]  do_syscall_64+0x3d/0x130
[   48.026056]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   48.026479] RIP: 0033:0x7f53b12082f6
[   48.026792] ...
[   48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm]
[   48.045001] Fixing recursive fault but reboot is needed!

This happens in:

static void __fput(struct file *file)
{   ...
    if (file->f_op->release)
        file->f_op->release(inode, file); <<< cdev is kfree'd here
    if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
             !(mode & FMODE_PATH))) {
        cdev_put(inode->i_cdev); <<< cdev fields are accessed here

Namely:

__fput()
  posix_clock_release()
    kref_put(&clk->kref, delete_clock) <<< the last reference
      delete_clock()
        delete_ptp_clock()
          kfree(ptp) <<< cdev is embedded in ptp
  cdev_put
    module_put(p->owner) <<< *p is kfree'd, bang!

Here cdev is embedded in posix_clock which is embedded in ptp_clock.
The race happens because ptp_clock's lifetime is controlled by two
refcounts: kref and cdev.kobj in posix_clock. This is wrong.

Make ptp_clock's sysfs device a parent of cdev with cdev_device_add()
created especially for such cases. This way the parent device with its
ptp_clock is not released until all references to the cdev are released.
This adds a requirement that an initialized but not exposed struct
device should be provided to posix_clock_register() by a caller instead
of a simple dev_t.

This approach was adopted from the commit 72139df ("watchdog: Fix
the race between the release of watchdog_core_data and cdev"). See
details of the implementation in the commit 233ed09 ("chardev: add
helper function to register char devs with a struct device").

Link: https://lore.kernel.org/linux-fsdevel/20191125125342.6189-1-vdronov@redhat.com/T/#u
Analyzed-by: Stephen Johnston <sjohnsto@redhat.com>
Analyzed-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Feb 2, 2020
[ Upstream commit a33121e ]

In a case when a ptp chardev (like /dev/ptp0) is open but an underlying
device is removed, closing this file leads to a race. This reproduces
easily in a kvm virtual machine:

ts# cat openptp0.c
int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); }
ts# uname -r
5.5.0-rc3-46cf053e
ts# cat /proc/cmdline
... slub_debug=FZP
ts# modprobe ptp_kvm
ts# ./openptp0 &
[1] 670
opened /dev/ptp0, sleeping 10s...
ts# rmmod ptp_kvm
ts# ls /dev/ptp*
ls: cannot access '/dev/ptp*': No such file or directory
ts# ...woken up
[   48.010809] general protection fault: 0000 [#1] SMP
[   48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25
[   48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
[   48.016270] RIP: 0010:module_put.part.0+0x7/0x80
[   48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202
[   48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0
[   48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b
[   48.019470] ...                                              ^^^ a slub poison
[   48.023854] Call Trace:
[   48.024050]  __fput+0x21f/0x240
[   48.024288]  task_work_run+0x79/0x90
[   48.024555]  do_exit+0x2af/0xab0
[   48.024799]  ? vfs_write+0x16a/0x190
[   48.025082]  do_group_exit+0x35/0x90
[   48.025387]  __x64_sys_exit_group+0xf/0x10
[   48.025737]  do_syscall_64+0x3d/0x130
[   48.026056]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   48.026479] RIP: 0033:0x7f53b12082f6
[   48.026792] ...
[   48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm]
[   48.045001] Fixing recursive fault but reboot is needed!

This happens in:

static void __fput(struct file *file)
{   ...
    if (file->f_op->release)
        file->f_op->release(inode, file); <<< cdev is kfree'd here
    if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
             !(mode & FMODE_PATH))) {
        cdev_put(inode->i_cdev); <<< cdev fields are accessed here

Namely:

__fput()
  posix_clock_release()
    kref_put(&clk->kref, delete_clock) <<< the last reference
      delete_clock()
        delete_ptp_clock()
          kfree(ptp) <<< cdev is embedded in ptp
  cdev_put
    module_put(p->owner) <<< *p is kfree'd, bang!

Here cdev is embedded in posix_clock which is embedded in ptp_clock.
The race happens because ptp_clock's lifetime is controlled by two
refcounts: kref and cdev.kobj in posix_clock. This is wrong.

Make ptp_clock's sysfs device a parent of cdev with cdev_device_add()
created especially for such cases. This way the parent device with its
ptp_clock is not released until all references to the cdev are released.
This adds a requirement that an initialized but not exposed struct
device should be provided to posix_clock_register() by a caller instead
of a simple dev_t.

This approach was adopted from the commit 72139df ("watchdog: Fix
the race between the release of watchdog_core_data and cdev"). See
details of the implementation in the commit 233ed09 ("chardev: add
helper function to register char devs with a struct device").

Link: https://lore.kernel.org/linux-fsdevel/20191125125342.6189-1-vdronov@redhat.com/T/#u
Analyzed-by: Stephen Johnston <sjohnsto@redhat.com>
Analyzed-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Jul 4, 2020
[ Upstream commit f6766ff ]

We need to check mddev->del_work before flush workqueu since the purpose
of flush is to ensure the previous md is disappeared. Otherwise the similar
deadlock appeared if LOCKDEP is enabled, it is due to md_open holds the
bdev->bd_mutex before flush workqueue.

kernel: [  154.522645] ======================================================
kernel: [  154.522647] WARNING: possible circular locking dependency detected
kernel: [  154.522650] 5.6.0-rc7-lp151.27-default #25 Tainted: G           O
kernel: [  154.522651] ------------------------------------------------------
kernel: [  154.522653] mdadm/2482 is trying to acquire lock:
kernel: [  154.522655] ffff888078529128 ((wq_completion)md_misc){+.+.}, at: flush_workqueue+0x84/0x4b0
kernel: [  154.522673]
kernel: [  154.522673] but task is already holding lock:
kernel: [  154.522675] ffff88804efa9338 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x79/0x590
kernel: [  154.522691]
kernel: [  154.522691] which lock already depends on the new lock.
kernel: [  154.522691]
kernel: [  154.522694]
kernel: [  154.522694] the existing dependency chain (in reverse order) is:
kernel: [  154.522696]
kernel: [  154.522696] -> #4 (&bdev->bd_mutex){+.+.}:
kernel: [  154.522704]        __mutex_lock+0x87/0x950
kernel: [  154.522706]        __blkdev_get+0x79/0x590
kernel: [  154.522708]        blkdev_get+0x65/0x140
kernel: [  154.522709]        blkdev_get_by_dev+0x2f/0x40
kernel: [  154.522716]        lock_rdev+0x3d/0x90 [md_mod]
kernel: [  154.522719]        md_import_device+0xd6/0x1b0 [md_mod]
kernel: [  154.522723]        new_dev_store+0x15e/0x210 [md_mod]
kernel: [  154.522728]        md_attr_store+0x7a/0xc0 [md_mod]
kernel: [  154.522732]        kernfs_fop_write+0x117/0x1b0
kernel: [  154.522735]        vfs_write+0xad/0x1a0
kernel: [  154.522737]        ksys_write+0xa4/0xe0
kernel: [  154.522745]        do_syscall_64+0x64/0x2b0
kernel: [  154.522748]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522749]
kernel: [  154.522749] -> #3 (&mddev->reconfig_mutex){+.+.}:
kernel: [  154.522752]        __mutex_lock+0x87/0x950
kernel: [  154.522756]        new_dev_store+0xc9/0x210 [md_mod]
kernel: [  154.522759]        md_attr_store+0x7a/0xc0 [md_mod]
kernel: [  154.522761]        kernfs_fop_write+0x117/0x1b0
kernel: [  154.522763]        vfs_write+0xad/0x1a0
kernel: [  154.522765]        ksys_write+0xa4/0xe0
kernel: [  154.522767]        do_syscall_64+0x64/0x2b0
kernel: [  154.522769]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522770]
kernel: [  154.522770] -> #2 (kn->count#253){++++}:
kernel: [  154.522775]        __kernfs_remove+0x253/0x2c0
kernel: [  154.522778]        kernfs_remove+0x1f/0x30
kernel: [  154.522780]        kobject_del+0x28/0x60
kernel: [  154.522783]        mddev_delayed_delete+0x24/0x30 [md_mod]
kernel: [  154.522786]        process_one_work+0x2a7/0x5f0
kernel: [  154.522788]        worker_thread+0x2d/0x3d0
kernel: [  154.522793]        kthread+0x117/0x130
kernel: [  154.522795]        ret_from_fork+0x3a/0x50
kernel: [  154.522796]
kernel: [  154.522796] -> #1 ((work_completion)(&mddev->del_work)){+.+.}:
kernel: [  154.522800]        process_one_work+0x27e/0x5f0
kernel: [  154.522802]        worker_thread+0x2d/0x3d0
kernel: [  154.522804]        kthread+0x117/0x130
kernel: [  154.522806]        ret_from_fork+0x3a/0x50
kernel: [  154.522807]
kernel: [  154.522807] -> #0 ((wq_completion)md_misc){+.+.}:
kernel: [  154.522813]        __lock_acquire+0x1392/0x1690
kernel: [  154.522816]        lock_acquire+0xb4/0x1a0
kernel: [  154.522818]        flush_workqueue+0xab/0x4b0
kernel: [  154.522821]        md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522823]        __blkdev_get+0xea/0x590
kernel: [  154.522825]        blkdev_get+0x65/0x140
kernel: [  154.522828]        do_dentry_open+0x1d1/0x380
kernel: [  154.522831]        path_openat+0x567/0xcc0
kernel: [  154.522834]        do_filp_open+0x9b/0x110
kernel: [  154.522836]        do_sys_openat2+0x201/0x2a0
kernel: [  154.522838]        do_sys_open+0x57/0x80
kernel: [  154.522840]        do_syscall_64+0x64/0x2b0
kernel: [  154.522842]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522844]
kernel: [  154.522844] other info that might help us debug this:
kernel: [  154.522844]
kernel: [  154.522846] Chain exists of:
kernel: [  154.522846]   (wq_completion)md_misc --> &mddev->reconfig_mutex --> &bdev->bd_mutex
kernel: [  154.522846]
kernel: [  154.522850]  Possible unsafe locking scenario:
kernel: [  154.522850]
kernel: [  154.522852]        CPU0                    CPU1
kernel: [  154.522853]        ----                    ----
kernel: [  154.522854]   lock(&bdev->bd_mutex);
kernel: [  154.522856]                                lock(&mddev->reconfig_mutex);
kernel: [  154.522858]                                lock(&bdev->bd_mutex);
kernel: [  154.522860]   lock((wq_completion)md_misc);
kernel: [  154.522861]
kernel: [  154.522861]  *** DEADLOCK ***
kernel: [  154.522861]
kernel: [  154.522864] 1 lock held by mdadm/2482:
kernel: [  154.522865]  #0: ffff88804efa9338 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x79/0x590
kernel: [  154.522868]
kernel: [  154.522868] stack backtrace:
kernel: [  154.522873] CPU: 1 PID: 2482 Comm: mdadm Tainted: G           O      5.6.0-rc7-lp151.27-default #25
kernel: [  154.522875] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
kernel: [  154.522878] Call Trace:
kernel: [  154.522881]  dump_stack+0x8f/0xcb
kernel: [  154.522884]  check_noncircular+0x194/0x1b0
kernel: [  154.522888]  ? __lock_acquire+0x1392/0x1690
kernel: [  154.522890]  __lock_acquire+0x1392/0x1690
kernel: [  154.522893]  lock_acquire+0xb4/0x1a0
kernel: [  154.522895]  ? flush_workqueue+0x84/0x4b0
kernel: [  154.522898]  flush_workqueue+0xab/0x4b0
kernel: [  154.522900]  ? flush_workqueue+0x84/0x4b0
kernel: [  154.522905]  ? md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522908]  md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522910]  __blkdev_get+0xea/0x590
kernel: [  154.522912]  ? bd_acquire+0xc0/0xc0
kernel: [  154.522914]  blkdev_get+0x65/0x140
kernel: [  154.522916]  ? bd_acquire+0xc0/0xc0
kernel: [  154.522918]  do_dentry_open+0x1d1/0x380
kernel: [  154.522921]  path_openat+0x567/0xcc0
kernel: [  154.522923]  ? __lock_acquire+0x380/0x1690
kernel: [  154.522926]  do_filp_open+0x9b/0x110
kernel: [  154.522929]  ? __alloc_fd+0xe5/0x1f0
kernel: [  154.522935]  ? kmem_cache_alloc+0x28c/0x630
kernel: [  154.522939]  ? do_sys_openat2+0x201/0x2a0
kernel: [  154.522941]  do_sys_openat2+0x201/0x2a0
kernel: [  154.522944]  do_sys_open+0x57/0x80
kernel: [  154.522946]  do_syscall_64+0x64/0x2b0
kernel: [  154.522948]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522951] RIP: 0033:0x7f98d279d9ae

And md_alloc also flushed the same workqueue, but the thing is different
here. Because all the paths call md_alloc don't hold bdev->bd_mutex, and
the flush is necessary to avoid race condition, so leave it as it is.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Jul 4, 2020
[ Upstream commit f6766ff ]

We need to check mddev->del_work before flush workqueu since the purpose
of flush is to ensure the previous md is disappeared. Otherwise the similar
deadlock appeared if LOCKDEP is enabled, it is due to md_open holds the
bdev->bd_mutex before flush workqueue.

kernel: [  154.522645] ======================================================
kernel: [  154.522647] WARNING: possible circular locking dependency detected
kernel: [  154.522650] 5.6.0-rc7-lp151.27-default #25 Tainted: G           O
kernel: [  154.522651] ------------------------------------------------------
kernel: [  154.522653] mdadm/2482 is trying to acquire lock:
kernel: [  154.522655] ffff888078529128 ((wq_completion)md_misc){+.+.}, at: flush_workqueue+0x84/0x4b0
kernel: [  154.522673]
kernel: [  154.522673] but task is already holding lock:
kernel: [  154.522675] ffff88804efa9338 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x79/0x590
kernel: [  154.522691]
kernel: [  154.522691] which lock already depends on the new lock.
kernel: [  154.522691]
kernel: [  154.522694]
kernel: [  154.522694] the existing dependency chain (in reverse order) is:
kernel: [  154.522696]
kernel: [  154.522696] -> #4 (&bdev->bd_mutex){+.+.}:
kernel: [  154.522704]        __mutex_lock+0x87/0x950
kernel: [  154.522706]        __blkdev_get+0x79/0x590
kernel: [  154.522708]        blkdev_get+0x65/0x140
kernel: [  154.522709]        blkdev_get_by_dev+0x2f/0x40
kernel: [  154.522716]        lock_rdev+0x3d/0x90 [md_mod]
kernel: [  154.522719]        md_import_device+0xd6/0x1b0 [md_mod]
kernel: [  154.522723]        new_dev_store+0x15e/0x210 [md_mod]
kernel: [  154.522728]        md_attr_store+0x7a/0xc0 [md_mod]
kernel: [  154.522732]        kernfs_fop_write+0x117/0x1b0
kernel: [  154.522735]        vfs_write+0xad/0x1a0
kernel: [  154.522737]        ksys_write+0xa4/0xe0
kernel: [  154.522745]        do_syscall_64+0x64/0x2b0
kernel: [  154.522748]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522749]
kernel: [  154.522749] -> #3 (&mddev->reconfig_mutex){+.+.}:
kernel: [  154.522752]        __mutex_lock+0x87/0x950
kernel: [  154.522756]        new_dev_store+0xc9/0x210 [md_mod]
kernel: [  154.522759]        md_attr_store+0x7a/0xc0 [md_mod]
kernel: [  154.522761]        kernfs_fop_write+0x117/0x1b0
kernel: [  154.522763]        vfs_write+0xad/0x1a0
kernel: [  154.522765]        ksys_write+0xa4/0xe0
kernel: [  154.522767]        do_syscall_64+0x64/0x2b0
kernel: [  154.522769]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522770]
kernel: [  154.522770] -> #2 (kn->count#253){++++}:
kernel: [  154.522775]        __kernfs_remove+0x253/0x2c0
kernel: [  154.522778]        kernfs_remove+0x1f/0x30
kernel: [  154.522780]        kobject_del+0x28/0x60
kernel: [  154.522783]        mddev_delayed_delete+0x24/0x30 [md_mod]
kernel: [  154.522786]        process_one_work+0x2a7/0x5f0
kernel: [  154.522788]        worker_thread+0x2d/0x3d0
kernel: [  154.522793]        kthread+0x117/0x130
kernel: [  154.522795]        ret_from_fork+0x3a/0x50
kernel: [  154.522796]
kernel: [  154.522796] -> #1 ((work_completion)(&mddev->del_work)){+.+.}:
kernel: [  154.522800]        process_one_work+0x27e/0x5f0
kernel: [  154.522802]        worker_thread+0x2d/0x3d0
kernel: [  154.522804]        kthread+0x117/0x130
kernel: [  154.522806]        ret_from_fork+0x3a/0x50
kernel: [  154.522807]
kernel: [  154.522807] -> #0 ((wq_completion)md_misc){+.+.}:
kernel: [  154.522813]        __lock_acquire+0x1392/0x1690
kernel: [  154.522816]        lock_acquire+0xb4/0x1a0
kernel: [  154.522818]        flush_workqueue+0xab/0x4b0
kernel: [  154.522821]        md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522823]        __blkdev_get+0xea/0x590
kernel: [  154.522825]        blkdev_get+0x65/0x140
kernel: [  154.522828]        do_dentry_open+0x1d1/0x380
kernel: [  154.522831]        path_openat+0x567/0xcc0
kernel: [  154.522834]        do_filp_open+0x9b/0x110
kernel: [  154.522836]        do_sys_openat2+0x201/0x2a0
kernel: [  154.522838]        do_sys_open+0x57/0x80
kernel: [  154.522840]        do_syscall_64+0x64/0x2b0
kernel: [  154.522842]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522844]
kernel: [  154.522844] other info that might help us debug this:
kernel: [  154.522844]
kernel: [  154.522846] Chain exists of:
kernel: [  154.522846]   (wq_completion)md_misc --> &mddev->reconfig_mutex --> &bdev->bd_mutex
kernel: [  154.522846]
kernel: [  154.522850]  Possible unsafe locking scenario:
kernel: [  154.522850]
kernel: [  154.522852]        CPU0                    CPU1
kernel: [  154.522853]        ----                    ----
kernel: [  154.522854]   lock(&bdev->bd_mutex);
kernel: [  154.522856]                                lock(&mddev->reconfig_mutex);
kernel: [  154.522858]                                lock(&bdev->bd_mutex);
kernel: [  154.522860]   lock((wq_completion)md_misc);
kernel: [  154.522861]
kernel: [  154.522861]  *** DEADLOCK ***
kernel: [  154.522861]
kernel: [  154.522864] 1 lock held by mdadm/2482:
kernel: [  154.522865]  #0: ffff88804efa9338 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x79/0x590
kernel: [  154.522868]
kernel: [  154.522868] stack backtrace:
kernel: [  154.522873] CPU: 1 PID: 2482 Comm: mdadm Tainted: G           O      5.6.0-rc7-lp151.27-default #25
kernel: [  154.522875] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
kernel: [  154.522878] Call Trace:
kernel: [  154.522881]  dump_stack+0x8f/0xcb
kernel: [  154.522884]  check_noncircular+0x194/0x1b0
kernel: [  154.522888]  ? __lock_acquire+0x1392/0x1690
kernel: [  154.522890]  __lock_acquire+0x1392/0x1690
kernel: [  154.522893]  lock_acquire+0xb4/0x1a0
kernel: [  154.522895]  ? flush_workqueue+0x84/0x4b0
kernel: [  154.522898]  flush_workqueue+0xab/0x4b0
kernel: [  154.522900]  ? flush_workqueue+0x84/0x4b0
kernel: [  154.522905]  ? md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522908]  md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522910]  __blkdev_get+0xea/0x590
kernel: [  154.522912]  ? bd_acquire+0xc0/0xc0
kernel: [  154.522914]  blkdev_get+0x65/0x140
kernel: [  154.522916]  ? bd_acquire+0xc0/0xc0
kernel: [  154.522918]  do_dentry_open+0x1d1/0x380
kernel: [  154.522921]  path_openat+0x567/0xcc0
kernel: [  154.522923]  ? __lock_acquire+0x380/0x1690
kernel: [  154.522926]  do_filp_open+0x9b/0x110
kernel: [  154.522929]  ? __alloc_fd+0xe5/0x1f0
kernel: [  154.522935]  ? kmem_cache_alloc+0x28c/0x630
kernel: [  154.522939]  ? do_sys_openat2+0x201/0x2a0
kernel: [  154.522941]  do_sys_openat2+0x201/0x2a0
kernel: [  154.522944]  do_sys_open+0x57/0x80
kernel: [  154.522946]  do_syscall_64+0x64/0x2b0
kernel: [  154.522948]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522951] RIP: 0033:0x7f98d279d9ae

And md_alloc also flushed the same workqueue, but the thing is different
here. Because all the paths call md_alloc don't hold bdev->bd_mutex, and
the flush is necessary to avoid race condition, so leave it as it is.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Mar 4, 2022
[ Upstream commit b132030 ]

A out-of-bounds bug can be triggered by an interrupt, the reason for
this bug is the lack of checking of register values.

In flexcop_pci_isr, the driver reads value from a register and uses it as
a dma address. Finally, this address will be passed to the count parameter
of find_next_packet. If this value is larger than the size of dma, the
index of buffer will be out-of-bounds.

Fix this by adding a check after reading the value of the register.

The following KASAN report reveals it:

BUG: KASAN: slab-out-of-bounds in find_next_packet
drivers/media/dvb-core/dvb_demux.c:528 [inline]
BUG: KASAN: slab-out-of-bounds in _dvb_dmx_swfilter
drivers/media/dvb-core/dvb_demux.c:572 [inline]
BUG: KASAN: slab-out-of-bounds in dvb_dmx_swfilter+0x3fa/0x420
drivers/media/dvb-core/dvb_demux.c:603
Read of size 1 at addr ffff8880608c00a0 by task swapper/2/0

CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xec/0x156 lib/dump_stack.c:118
 print_address_description+0x78/0x290 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x25b/0x380 mm/kasan/report.c:412
 __asan_report_load1_noabort+0x19/0x20 mm/kasan/report.c:430
 find_next_packet drivers/media/dvb-core/dvb_demux.c:528 [inline]
 _dvb_dmx_swfilter drivers/media/dvb-core/dvb_demux.c:572 [inline]
 dvb_dmx_swfilter+0x3fa/0x420 drivers/media/dvb-core/dvb_demux.c:603
 flexcop_pass_dmx_data+0x2e/0x40 drivers/media/common/b2c2/flexcop.c:167
 flexcop_pci_isr+0x3d1/0x5d0 drivers/media/pci/b2c2/flexcop-pci.c:212
 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149
 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189
 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206
 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725
 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline]
 handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87
 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670
 </IRQ>
RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61
Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 62 2f 8c 48 89 e5 e8 fb 31
e8 f8 8b 05 75 4f 8e 03 85 c0 7e 07 0f 00 2d 8a 61 66 00 fb f4 <5d> c3
90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41
RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde
RAX: 0000000000000000 RBX: ffffffff8bde44c8 RCX: ffffffff88a11285
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2f6200
RBP: ffff88806b71fcc8 R08: fffffbfff185ec40 R09: fffffbfff185ec40
R10: 0000000000000001 R11: fffffbfff185ec40 R12: 0000000000000002
R13: ffffffff8be9d6e0 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x6f/0x360 arch/x86/kernel/process.c:557
 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263
 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369
 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

Allocated by task 1:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x11/0x20 mm/kasan/kasan.c:490
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2741 [inline]
 slab_alloc mm/slub.c:2749 [inline]
 kmem_cache_alloc+0xeb/0x280 mm/slub.c:2754
 kmem_cache_zalloc include/linux/slab.h:699 [inline]
 __kernfs_new_node+0xe2/0x6f0 fs/kernfs/dir.c:633
 kernfs_new_node+0x9a/0x120 fs/kernfs/dir.c:693
 __kernfs_create_file+0x5f/0x340 fs/kernfs/file.c:992
 sysfs_add_file_mode_ns+0x22a/0x4e0 fs/sysfs/file.c:306
 create_files fs/sysfs/group.c:63 [inline]
 internal_create_group+0x34e/0xc30 fs/sysfs/group.c:147
 sysfs_create_group fs/sysfs/group.c:173 [inline]
 sysfs_create_groups+0x9c/0x140 fs/sysfs/group.c:200
 driver_add_groups+0x3e/0x50 drivers/base/driver.c:129
 bus_add_driver+0x3a5/0x790 drivers/base/bus.c:684
 driver_register+0x1cd/0x410 drivers/base/driver.c:170
 __pci_register_driver+0x197/0x200 drivers/pci/pci-driver.c:1411
 cx88_audio_pci_driver_init+0x23/0x25 drivers/media/pci/cx88/cx88-alsa.c:
 1017
 do_one_initcall+0xe0/0x610 init/main.c:884
 do_initcall_level init/main.c:952 [inline]
 do_initcalls init/main.c:960 [inline]
 do_basic_setup init/main.c:978 [inline]
 kernel_init_freeable+0x4d0/0x592 init/main.c:1145
 kernel_init+0x18/0x190 init/main.c:1062
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8880608c0000
 which belongs to the cache kernfs_node_cache of size 160
The buggy address is located 0 bytes to the right of
 160-byte region [ffff8880608c0000, ffff8880608c00a0)
The buggy address belongs to the page:
page:ffffea0001823000 count:1 mapcount:0 mapping:ffff88806bed1e00
index:0x0 compound_mapcount: 0
flags: 0x100000000008100(slab|head)
raw: 0100000000008100 dead000000000100 dead000000000200 ffff88806bed1e00
raw: 0000000000000000 0000000000240024 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880608bff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880608c0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880608c0080: 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 00
                               ^
 ffff8880608c0100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880608c0180: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
==================================================================

Link: https://lore.kernel.org/linux-media/1620723603-30912-1-git-send-email-zheyuma97@gmail.com
Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Mar 19, 2022
[ Upstream commit 4224cfd ]

When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <suresh2514@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Apr 8, 2022
[ Upstream commit b132030 ]

A out-of-bounds bug can be triggered by an interrupt, the reason for
this bug is the lack of checking of register values.

In flexcop_pci_isr, the driver reads value from a register and uses it as
a dma address. Finally, this address will be passed to the count parameter
of find_next_packet. If this value is larger than the size of dma, the
index of buffer will be out-of-bounds.

Fix this by adding a check after reading the value of the register.

The following KASAN report reveals it:

BUG: KASAN: slab-out-of-bounds in find_next_packet
drivers/media/dvb-core/dvb_demux.c:528 [inline]
BUG: KASAN: slab-out-of-bounds in _dvb_dmx_swfilter
drivers/media/dvb-core/dvb_demux.c:572 [inline]
BUG: KASAN: slab-out-of-bounds in dvb_dmx_swfilter+0x3fa/0x420
drivers/media/dvb-core/dvb_demux.c:603
Read of size 1 at addr ffff8880608c00a0 by task swapper/2/0

CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xec/0x156 lib/dump_stack.c:118
 print_address_description+0x78/0x290 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x25b/0x380 mm/kasan/report.c:412
 __asan_report_load1_noabort+0x19/0x20 mm/kasan/report.c:430
 find_next_packet drivers/media/dvb-core/dvb_demux.c:528 [inline]
 _dvb_dmx_swfilter drivers/media/dvb-core/dvb_demux.c:572 [inline]
 dvb_dmx_swfilter+0x3fa/0x420 drivers/media/dvb-core/dvb_demux.c:603
 flexcop_pass_dmx_data+0x2e/0x40 drivers/media/common/b2c2/flexcop.c:167
 flexcop_pci_isr+0x3d1/0x5d0 drivers/media/pci/b2c2/flexcop-pci.c:212
 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149
 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189
 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206
 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725
 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline]
 handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87
 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670
 </IRQ>
RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61
Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 62 2f 8c 48 89 e5 e8 fb 31
e8 f8 8b 05 75 4f 8e 03 85 c0 7e 07 0f 00 2d 8a 61 66 00 fb f4 <5d> c3
90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41
RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde
RAX: 0000000000000000 RBX: ffffffff8bde44c8 RCX: ffffffff88a11285
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2f6200
RBP: ffff88806b71fcc8 R08: fffffbfff185ec40 R09: fffffbfff185ec40
R10: 0000000000000001 R11: fffffbfff185ec40 R12: 0000000000000002
R13: ffffffff8be9d6e0 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x6f/0x360 arch/x86/kernel/process.c:557
 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263
 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369
 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

Allocated by task 1:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x11/0x20 mm/kasan/kasan.c:490
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2741 [inline]
 slab_alloc mm/slub.c:2749 [inline]
 kmem_cache_alloc+0xeb/0x280 mm/slub.c:2754
 kmem_cache_zalloc include/linux/slab.h:699 [inline]
 __kernfs_new_node+0xe2/0x6f0 fs/kernfs/dir.c:633
 kernfs_new_node+0x9a/0x120 fs/kernfs/dir.c:693
 __kernfs_create_file+0x5f/0x340 fs/kernfs/file.c:992
 sysfs_add_file_mode_ns+0x22a/0x4e0 fs/sysfs/file.c:306
 create_files fs/sysfs/group.c:63 [inline]
 internal_create_group+0x34e/0xc30 fs/sysfs/group.c:147
 sysfs_create_group fs/sysfs/group.c:173 [inline]
 sysfs_create_groups+0x9c/0x140 fs/sysfs/group.c:200
 driver_add_groups+0x3e/0x50 drivers/base/driver.c:129
 bus_add_driver+0x3a5/0x790 drivers/base/bus.c:684
 driver_register+0x1cd/0x410 drivers/base/driver.c:170
 __pci_register_driver+0x197/0x200 drivers/pci/pci-driver.c:1411
 cx88_audio_pci_driver_init+0x23/0x25 drivers/media/pci/cx88/cx88-alsa.c:
 1017
 do_one_initcall+0xe0/0x610 init/main.c:884
 do_initcall_level init/main.c:952 [inline]
 do_initcalls init/main.c:960 [inline]
 do_basic_setup init/main.c:978 [inline]
 kernel_init_freeable+0x4d0/0x592 init/main.c:1145
 kernel_init+0x18/0x190 init/main.c:1062
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8880608c0000
 which belongs to the cache kernfs_node_cache of size 160
The buggy address is located 0 bytes to the right of
 160-byte region [ffff8880608c0000, ffff8880608c00a0)
The buggy address belongs to the page:
page:ffffea0001823000 count:1 mapcount:0 mapping:ffff88806bed1e00
index:0x0 compound_mapcount: 0
flags: 0x100000000008100(slab|head)
raw: 0100000000008100 dead000000000100 dead000000000200 ffff88806bed1e00
raw: 0000000000000000 0000000000240024 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880608bff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880608c0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880608c0080: 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 00
                               ^
 ffff8880608c0100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880608c0180: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
==================================================================

Link: https://lore.kernel.org/linux-media/1620723603-30912-1-git-send-email-zheyuma97@gmail.com
Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Apr 8, 2022
[ Upstream commit 4224cfd ]

When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <suresh2514@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Apr 8, 2022
[ Upstream commit b132030 ]

A out-of-bounds bug can be triggered by an interrupt, the reason for
this bug is the lack of checking of register values.

In flexcop_pci_isr, the driver reads value from a register and uses it as
a dma address. Finally, this address will be passed to the count parameter
of find_next_packet. If this value is larger than the size of dma, the
index of buffer will be out-of-bounds.

Fix this by adding a check after reading the value of the register.

The following KASAN report reveals it:

BUG: KASAN: slab-out-of-bounds in find_next_packet
drivers/media/dvb-core/dvb_demux.c:528 [inline]
BUG: KASAN: slab-out-of-bounds in _dvb_dmx_swfilter
drivers/media/dvb-core/dvb_demux.c:572 [inline]
BUG: KASAN: slab-out-of-bounds in dvb_dmx_swfilter+0x3fa/0x420
drivers/media/dvb-core/dvb_demux.c:603
Read of size 1 at addr ffff8880608c00a0 by task swapper/2/0

CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xec/0x156 lib/dump_stack.c:118
 print_address_description+0x78/0x290 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x25b/0x380 mm/kasan/report.c:412
 __asan_report_load1_noabort+0x19/0x20 mm/kasan/report.c:430
 find_next_packet drivers/media/dvb-core/dvb_demux.c:528 [inline]
 _dvb_dmx_swfilter drivers/media/dvb-core/dvb_demux.c:572 [inline]
 dvb_dmx_swfilter+0x3fa/0x420 drivers/media/dvb-core/dvb_demux.c:603
 flexcop_pass_dmx_data+0x2e/0x40 drivers/media/common/b2c2/flexcop.c:167
 flexcop_pci_isr+0x3d1/0x5d0 drivers/media/pci/b2c2/flexcop-pci.c:212
 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149
 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189
 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206
 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725
 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline]
 handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87
 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670
 </IRQ>
RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61
Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 62 2f 8c 48 89 e5 e8 fb 31
e8 f8 8b 05 75 4f 8e 03 85 c0 7e 07 0f 00 2d 8a 61 66 00 fb f4 <5d> c3
90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41
RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde
RAX: 0000000000000000 RBX: ffffffff8bde44c8 RCX: ffffffff88a11285
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2f6200
RBP: ffff88806b71fcc8 R08: fffffbfff185ec40 R09: fffffbfff185ec40
R10: 0000000000000001 R11: fffffbfff185ec40 R12: 0000000000000002
R13: ffffffff8be9d6e0 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x6f/0x360 arch/x86/kernel/process.c:557
 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263
 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369
 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

Allocated by task 1:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x11/0x20 mm/kasan/kasan.c:490
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2741 [inline]
 slab_alloc mm/slub.c:2749 [inline]
 kmem_cache_alloc+0xeb/0x280 mm/slub.c:2754
 kmem_cache_zalloc include/linux/slab.h:699 [inline]
 __kernfs_new_node+0xe2/0x6f0 fs/kernfs/dir.c:633
 kernfs_new_node+0x9a/0x120 fs/kernfs/dir.c:693
 __kernfs_create_file+0x5f/0x340 fs/kernfs/file.c:992
 sysfs_add_file_mode_ns+0x22a/0x4e0 fs/sysfs/file.c:306
 create_files fs/sysfs/group.c:63 [inline]
 internal_create_group+0x34e/0xc30 fs/sysfs/group.c:147
 sysfs_create_group fs/sysfs/group.c:173 [inline]
 sysfs_create_groups+0x9c/0x140 fs/sysfs/group.c:200
 driver_add_groups+0x3e/0x50 drivers/base/driver.c:129
 bus_add_driver+0x3a5/0x790 drivers/base/bus.c:684
 driver_register+0x1cd/0x410 drivers/base/driver.c:170
 __pci_register_driver+0x197/0x200 drivers/pci/pci-driver.c:1411
 cx88_audio_pci_driver_init+0x23/0x25 drivers/media/pci/cx88/cx88-alsa.c:
 1017
 do_one_initcall+0xe0/0x610 init/main.c:884
 do_initcall_level init/main.c:952 [inline]
 do_initcalls init/main.c:960 [inline]
 do_basic_setup init/main.c:978 [inline]
 kernel_init_freeable+0x4d0/0x592 init/main.c:1145
 kernel_init+0x18/0x190 init/main.c:1062
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8880608c0000
 which belongs to the cache kernfs_node_cache of size 160
The buggy address is located 0 bytes to the right of
 160-byte region [ffff8880608c0000, ffff8880608c00a0)
The buggy address belongs to the page:
page:ffffea0001823000 count:1 mapcount:0 mapping:ffff88806bed1e00
index:0x0 compound_mapcount: 0
flags: 0x100000000008100(slab|head)
raw: 0100000000008100 dead000000000100 dead000000000200 ffff88806bed1e00
raw: 0000000000000000 0000000000240024 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880608bff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880608c0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880608c0080: 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 00
                               ^
 ffff8880608c0100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880608c0180: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
==================================================================

Link: https://lore.kernel.org/linux-media/1620723603-30912-1-git-send-email-zheyuma97@gmail.com
Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Apr 8, 2022
[ Upstream commit 4224cfd ]

When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <suresh2514@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Nov 28, 2022
commit 1e41e69 upstream.

UBSAN complains about array-index-out-of-bounds:
[ 1.980703] kernel: UBSAN: array-index-out-of-bounds in /build/linux-9H675w/linux-5.15.0/drivers/ata/libahci.c:968:41
[ 1.980709] kernel: index 15 is out of range for type 'ahci_em_priv [8]'
[ 1.980713] kernel: CPU: 0 PID: 209 Comm: scsi_eh_8 Not tainted 5.15.0-25-generic #25-Ubuntu
[ 1.980716] kernel: Hardware name: System manufacturer System Product Name/P5Q3, BIOS 1102 06/11/2010
[ 1.980718] kernel: Call Trace:
[ 1.980721] kernel: <TASK>
[ 1.980723] kernel: show_stack+0x52/0x58
[ 1.980729] kernel: dump_stack_lvl+0x4a/0x5f
[ 1.980734] kernel: dump_stack+0x10/0x12
[ 1.980736] kernel: ubsan_epilogue+0x9/0x45
[ 1.980739] kernel: __ubsan_handle_out_of_bounds.cold+0x44/0x49
[ 1.980742] kernel: ahci_qc_issue+0x166/0x170 [libahci]
[ 1.980748] kernel: ata_qc_issue+0x135/0x240
[ 1.980752] kernel: ata_exec_internal_sg+0x2c4/0x580
[ 1.980754] kernel: ? vprintk_default+0x1d/0x20
[ 1.980759] kernel: ata_exec_internal+0x67/0xa0
[ 1.980762] kernel: sata_pmp_read+0x8d/0xc0
[ 1.980765] kernel: sata_pmp_read_gscr+0x3c/0x90
[ 1.980768] kernel: sata_pmp_attach+0x8b/0x310
[ 1.980771] kernel: ata_eh_revalidate_and_attach+0x28c/0x4b0
[ 1.980775] kernel: ata_eh_recover+0x6b6/0xb30
[ 1.980778] kernel: ? ahci_do_hardreset+0x180/0x180 [libahci]
[ 1.980783] kernel: ? ahci_stop_engine+0xb0/0xb0 [libahci]
[ 1.980787] kernel: ? ahci_do_softreset+0x290/0x290 [libahci]
[ 1.980792] kernel: ? trace_event_raw_event_ata_eh_link_autopsy_qc+0xe0/0xe0
[ 1.980795] kernel: sata_pmp_eh_recover.isra.0+0x214/0x560
[ 1.980799] kernel: sata_pmp_error_handler+0x23/0x40
[ 1.980802] kernel: ahci_error_handler+0x43/0x80 [libahci]
[ 1.980806] kernel: ata_scsi_port_error_handler+0x2b1/0x600
[ 1.980810] kernel: ata_scsi_error+0x9c/0xd0
[ 1.980813] kernel: scsi_error_handler+0xa1/0x180
[ 1.980817] kernel: ? scsi_unjam_host+0x1c0/0x1c0
[ 1.980820] kernel: kthread+0x12a/0x150
[ 1.980823] kernel: ? set_kthread_struct+0x50/0x50
[ 1.980826] kernel: ret_from_fork+0x22/0x30
[ 1.980831] kernel: </TASK>

This happens because sata_pmp_init_links() initialize link->pmp up to
SATA_PMP_MAX_PORTS while em_priv is declared as 8 elements array.

I can't find the maximum Enclosure Management ports specified in AHCI
spec v1.3.1, but "12.2.1 LED message type" states that "Port Multiplier
Information" can utilize 4 bits, which implies it can support up to 16
ports. Hence, use SATA_PMP_MAX_PORTS as EM_MAX_SLOTS to resolve the
issue.

BugLink: https://bugs.launchpad.net/bugs/1970074
Cc: stable@vger.kernel.org
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Nov 28, 2022
commit 1e41e69 upstream.

UBSAN complains about array-index-out-of-bounds:
[ 1.980703] kernel: UBSAN: array-index-out-of-bounds in /build/linux-9H675w/linux-5.15.0/drivers/ata/libahci.c:968:41
[ 1.980709] kernel: index 15 is out of range for type 'ahci_em_priv [8]'
[ 1.980713] kernel: CPU: 0 PID: 209 Comm: scsi_eh_8 Not tainted 5.15.0-25-generic #25-Ubuntu
[ 1.980716] kernel: Hardware name: System manufacturer System Product Name/P5Q3, BIOS 1102 06/11/2010
[ 1.980718] kernel: Call Trace:
[ 1.980721] kernel: <TASK>
[ 1.980723] kernel: show_stack+0x52/0x58
[ 1.980729] kernel: dump_stack_lvl+0x4a/0x5f
[ 1.980734] kernel: dump_stack+0x10/0x12
[ 1.980736] kernel: ubsan_epilogue+0x9/0x45
[ 1.980739] kernel: __ubsan_handle_out_of_bounds.cold+0x44/0x49
[ 1.980742] kernel: ahci_qc_issue+0x166/0x170 [libahci]
[ 1.980748] kernel: ata_qc_issue+0x135/0x240
[ 1.980752] kernel: ata_exec_internal_sg+0x2c4/0x580
[ 1.980754] kernel: ? vprintk_default+0x1d/0x20
[ 1.980759] kernel: ata_exec_internal+0x67/0xa0
[ 1.980762] kernel: sata_pmp_read+0x8d/0xc0
[ 1.980765] kernel: sata_pmp_read_gscr+0x3c/0x90
[ 1.980768] kernel: sata_pmp_attach+0x8b/0x310
[ 1.980771] kernel: ata_eh_revalidate_and_attach+0x28c/0x4b0
[ 1.980775] kernel: ata_eh_recover+0x6b6/0xb30
[ 1.980778] kernel: ? ahci_do_hardreset+0x180/0x180 [libahci]
[ 1.980783] kernel: ? ahci_stop_engine+0xb0/0xb0 [libahci]
[ 1.980787] kernel: ? ahci_do_softreset+0x290/0x290 [libahci]
[ 1.980792] kernel: ? trace_event_raw_event_ata_eh_link_autopsy_qc+0xe0/0xe0
[ 1.980795] kernel: sata_pmp_eh_recover.isra.0+0x214/0x560
[ 1.980799] kernel: sata_pmp_error_handler+0x23/0x40
[ 1.980802] kernel: ahci_error_handler+0x43/0x80 [libahci]
[ 1.980806] kernel: ata_scsi_port_error_handler+0x2b1/0x600
[ 1.980810] kernel: ata_scsi_error+0x9c/0xd0
[ 1.980813] kernel: scsi_error_handler+0xa1/0x180
[ 1.980817] kernel: ? scsi_unjam_host+0x1c0/0x1c0
[ 1.980820] kernel: kthread+0x12a/0x150
[ 1.980823] kernel: ? set_kthread_struct+0x50/0x50
[ 1.980826] kernel: ret_from_fork+0x22/0x30
[ 1.980831] kernel: </TASK>

This happens because sata_pmp_init_links() initialize link->pmp up to
SATA_PMP_MAX_PORTS while em_priv is declared as 8 elements array.

I can't find the maximum Enclosure Management ports specified in AHCI
spec v1.3.1, but "12.2.1 LED message type" states that "Port Multiplier
Information" can utilize 4 bits, which implies it can support up to 16
ports. Hence, use SATA_PMP_MAX_PORTS as EM_MAX_SLOTS to resolve the
issue.

BugLink: https://bugs.launchpad.net/bugs/1970074
Cc: stable@vger.kernel.org
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Nov 28, 2022
commit 1e41e69 upstream.

UBSAN complains about array-index-out-of-bounds:
[ 1.980703] kernel: UBSAN: array-index-out-of-bounds in /build/linux-9H675w/linux-5.15.0/drivers/ata/libahci.c:968:41
[ 1.980709] kernel: index 15 is out of range for type 'ahci_em_priv [8]'
[ 1.980713] kernel: CPU: 0 PID: 209 Comm: scsi_eh_8 Not tainted 5.15.0-25-generic #25-Ubuntu
[ 1.980716] kernel: Hardware name: System manufacturer System Product Name/P5Q3, BIOS 1102 06/11/2010
[ 1.980718] kernel: Call Trace:
[ 1.980721] kernel: <TASK>
[ 1.980723] kernel: show_stack+0x52/0x58
[ 1.980729] kernel: dump_stack_lvl+0x4a/0x5f
[ 1.980734] kernel: dump_stack+0x10/0x12
[ 1.980736] kernel: ubsan_epilogue+0x9/0x45
[ 1.980739] kernel: __ubsan_handle_out_of_bounds.cold+0x44/0x49
[ 1.980742] kernel: ahci_qc_issue+0x166/0x170 [libahci]
[ 1.980748] kernel: ata_qc_issue+0x135/0x240
[ 1.980752] kernel: ata_exec_internal_sg+0x2c4/0x580
[ 1.980754] kernel: ? vprintk_default+0x1d/0x20
[ 1.980759] kernel: ata_exec_internal+0x67/0xa0
[ 1.980762] kernel: sata_pmp_read+0x8d/0xc0
[ 1.980765] kernel: sata_pmp_read_gscr+0x3c/0x90
[ 1.980768] kernel: sata_pmp_attach+0x8b/0x310
[ 1.980771] kernel: ata_eh_revalidate_and_attach+0x28c/0x4b0
[ 1.980775] kernel: ata_eh_recover+0x6b6/0xb30
[ 1.980778] kernel: ? ahci_do_hardreset+0x180/0x180 [libahci]
[ 1.980783] kernel: ? ahci_stop_engine+0xb0/0xb0 [libahci]
[ 1.980787] kernel: ? ahci_do_softreset+0x290/0x290 [libahci]
[ 1.980792] kernel: ? trace_event_raw_event_ata_eh_link_autopsy_qc+0xe0/0xe0
[ 1.980795] kernel: sata_pmp_eh_recover.isra.0+0x214/0x560
[ 1.980799] kernel: sata_pmp_error_handler+0x23/0x40
[ 1.980802] kernel: ahci_error_handler+0x43/0x80 [libahci]
[ 1.980806] kernel: ata_scsi_port_error_handler+0x2b1/0x600
[ 1.980810] kernel: ata_scsi_error+0x9c/0xd0
[ 1.980813] kernel: scsi_error_handler+0xa1/0x180
[ 1.980817] kernel: ? scsi_unjam_host+0x1c0/0x1c0
[ 1.980820] kernel: kthread+0x12a/0x150
[ 1.980823] kernel: ? set_kthread_struct+0x50/0x50
[ 1.980826] kernel: ret_from_fork+0x22/0x30
[ 1.980831] kernel: </TASK>

This happens because sata_pmp_init_links() initialize link->pmp up to
SATA_PMP_MAX_PORTS while em_priv is declared as 8 elements array.

I can't find the maximum Enclosure Management ports specified in AHCI
spec v1.3.1, but "12.2.1 LED message type" states that "Port Multiplier
Information" can utilize 4 bits, which implies it can support up to 16
ports. Hence, use SATA_PMP_MAX_PORTS as EM_MAX_SLOTS to resolve the
issue.

BugLink: https://bugs.launchpad.net/bugs/1970074
Cc: stable@vger.kernel.org
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Nov 28, 2022
commit 1e41e69 upstream.

UBSAN complains about array-index-out-of-bounds:
[ 1.980703] kernel: UBSAN: array-index-out-of-bounds in /build/linux-9H675w/linux-5.15.0/drivers/ata/libahci.c:968:41
[ 1.980709] kernel: index 15 is out of range for type 'ahci_em_priv [8]'
[ 1.980713] kernel: CPU: 0 PID: 209 Comm: scsi_eh_8 Not tainted 5.15.0-25-generic #25-Ubuntu
[ 1.980716] kernel: Hardware name: System manufacturer System Product Name/P5Q3, BIOS 1102 06/11/2010
[ 1.980718] kernel: Call Trace:
[ 1.980721] kernel: <TASK>
[ 1.980723] kernel: show_stack+0x52/0x58
[ 1.980729] kernel: dump_stack_lvl+0x4a/0x5f
[ 1.980734] kernel: dump_stack+0x10/0x12
[ 1.980736] kernel: ubsan_epilogue+0x9/0x45
[ 1.980739] kernel: __ubsan_handle_out_of_bounds.cold+0x44/0x49
[ 1.980742] kernel: ahci_qc_issue+0x166/0x170 [libahci]
[ 1.980748] kernel: ata_qc_issue+0x135/0x240
[ 1.980752] kernel: ata_exec_internal_sg+0x2c4/0x580
[ 1.980754] kernel: ? vprintk_default+0x1d/0x20
[ 1.980759] kernel: ata_exec_internal+0x67/0xa0
[ 1.980762] kernel: sata_pmp_read+0x8d/0xc0
[ 1.980765] kernel: sata_pmp_read_gscr+0x3c/0x90
[ 1.980768] kernel: sata_pmp_attach+0x8b/0x310
[ 1.980771] kernel: ata_eh_revalidate_and_attach+0x28c/0x4b0
[ 1.980775] kernel: ata_eh_recover+0x6b6/0xb30
[ 1.980778] kernel: ? ahci_do_hardreset+0x180/0x180 [libahci]
[ 1.980783] kernel: ? ahci_stop_engine+0xb0/0xb0 [libahci]
[ 1.980787] kernel: ? ahci_do_softreset+0x290/0x290 [libahci]
[ 1.980792] kernel: ? trace_event_raw_event_ata_eh_link_autopsy_qc+0xe0/0xe0
[ 1.980795] kernel: sata_pmp_eh_recover.isra.0+0x214/0x560
[ 1.980799] kernel: sata_pmp_error_handler+0x23/0x40
[ 1.980802] kernel: ahci_error_handler+0x43/0x80 [libahci]
[ 1.980806] kernel: ata_scsi_port_error_handler+0x2b1/0x600
[ 1.980810] kernel: ata_scsi_error+0x9c/0xd0
[ 1.980813] kernel: scsi_error_handler+0xa1/0x180
[ 1.980817] kernel: ? scsi_unjam_host+0x1c0/0x1c0
[ 1.980820] kernel: kthread+0x12a/0x150
[ 1.980823] kernel: ? set_kthread_struct+0x50/0x50
[ 1.980826] kernel: ret_from_fork+0x22/0x30
[ 1.980831] kernel: </TASK>

This happens because sata_pmp_init_links() initialize link->pmp up to
SATA_PMP_MAX_PORTS while em_priv is declared as 8 elements array.

I can't find the maximum Enclosure Management ports specified in AHCI
spec v1.3.1, but "12.2.1 LED message type" states that "Port Multiplier
Information" can utilize 4 bits, which implies it can support up to 16
ports. Hence, use SATA_PMP_MAX_PORTS as EM_MAX_SLOTS to resolve the
issue.

BugLink: https://bugs.launchpad.net/bugs/1970074
Cc: stable@vger.kernel.org
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Nov 28, 2022
commit 1e41e69 upstream.

UBSAN complains about array-index-out-of-bounds:
[ 1.980703] kernel: UBSAN: array-index-out-of-bounds in /build/linux-9H675w/linux-5.15.0/drivers/ata/libahci.c:968:41
[ 1.980709] kernel: index 15 is out of range for type 'ahci_em_priv [8]'
[ 1.980713] kernel: CPU: 0 PID: 209 Comm: scsi_eh_8 Not tainted 5.15.0-25-generic #25-Ubuntu
[ 1.980716] kernel: Hardware name: System manufacturer System Product Name/P5Q3, BIOS 1102 06/11/2010
[ 1.980718] kernel: Call Trace:
[ 1.980721] kernel: <TASK>
[ 1.980723] kernel: show_stack+0x52/0x58
[ 1.980729] kernel: dump_stack_lvl+0x4a/0x5f
[ 1.980734] kernel: dump_stack+0x10/0x12
[ 1.980736] kernel: ubsan_epilogue+0x9/0x45
[ 1.980739] kernel: __ubsan_handle_out_of_bounds.cold+0x44/0x49
[ 1.980742] kernel: ahci_qc_issue+0x166/0x170 [libahci]
[ 1.980748] kernel: ata_qc_issue+0x135/0x240
[ 1.980752] kernel: ata_exec_internal_sg+0x2c4/0x580
[ 1.980754] kernel: ? vprintk_default+0x1d/0x20
[ 1.980759] kernel: ata_exec_internal+0x67/0xa0
[ 1.980762] kernel: sata_pmp_read+0x8d/0xc0
[ 1.980765] kernel: sata_pmp_read_gscr+0x3c/0x90
[ 1.980768] kernel: sata_pmp_attach+0x8b/0x310
[ 1.980771] kernel: ata_eh_revalidate_and_attach+0x28c/0x4b0
[ 1.980775] kernel: ata_eh_recover+0x6b6/0xb30
[ 1.980778] kernel: ? ahci_do_hardreset+0x180/0x180 [libahci]
[ 1.980783] kernel: ? ahci_stop_engine+0xb0/0xb0 [libahci]
[ 1.980787] kernel: ? ahci_do_softreset+0x290/0x290 [libahci]
[ 1.980792] kernel: ? trace_event_raw_event_ata_eh_link_autopsy_qc+0xe0/0xe0
[ 1.980795] kernel: sata_pmp_eh_recover.isra.0+0x214/0x560
[ 1.980799] kernel: sata_pmp_error_handler+0x23/0x40
[ 1.980802] kernel: ahci_error_handler+0x43/0x80 [libahci]
[ 1.980806] kernel: ata_scsi_port_error_handler+0x2b1/0x600
[ 1.980810] kernel: ata_scsi_error+0x9c/0xd0
[ 1.980813] kernel: scsi_error_handler+0xa1/0x180
[ 1.980817] kernel: ? scsi_unjam_host+0x1c0/0x1c0
[ 1.980820] kernel: kthread+0x12a/0x150
[ 1.980823] kernel: ? set_kthread_struct+0x50/0x50
[ 1.980826] kernel: ret_from_fork+0x22/0x30
[ 1.980831] kernel: </TASK>

This happens because sata_pmp_init_links() initialize link->pmp up to
SATA_PMP_MAX_PORTS while em_priv is declared as 8 elements array.

I can't find the maximum Enclosure Management ports specified in AHCI
spec v1.3.1, but "12.2.1 LED message type" states that "Port Multiplier
Information" can utilize 4 bits, which implies it can support up to 16
ports. Hence, use SATA_PMP_MAX_PORTS as EM_MAX_SLOTS to resolve the
issue.

BugLink: https://bugs.launchpad.net/bugs/1970074
Cc: stable@vger.kernel.org
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Mar 18, 2023
[ Upstream commit 803766c ]

The pasid_lock is used to synchronize different threads from modifying a
same pasid directory entry at the same time. It causes below lockdep splat.

[   83.296538] ========================================================
[   83.296538] WARNING: possible irq lock inversion dependency detected
[   83.296539] 5.12.0-rc3+ #25 Tainted: G        W
[   83.296539] --------------------------------------------------------
[   83.296540] bash/780 just changed the state of lock:
[   83.296540] ffffffff82b29c98 (device_domain_lock){..-.}-{2:2}, at:
           iommu_flush_dev_iotlb.part.0+0x32/0x110
[   83.296547] but this lock took another, SOFTIRQ-unsafe lock in the past:
[   83.296547]  (pasid_lock){+.+.}-{2:2}
[   83.296548]

           and interrupts could create inverse lock ordering between them.

[   83.296549] other info that might help us debug this:
[   83.296549] Chain exists of:
                 device_domain_lock --> &iommu->lock --> pasid_lock
[   83.296551]  Possible interrupt unsafe locking scenario:

[   83.296551]        CPU0                    CPU1
[   83.296552]        ----                    ----
[   83.296552]   lock(pasid_lock);
[   83.296553]                                local_irq_disable();
[   83.296553]                                lock(device_domain_lock);
[   83.296554]                                lock(&iommu->lock);
[   83.296554]   <Interrupt>
[   83.296554]     lock(device_domain_lock);
[   83.296555]
                *** DEADLOCK ***

Fix it by replacing the pasid_lock with an atomic exchange operation.

Reported-and-tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210320020916.640115-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Stable-dep-of: 194b334 ("iommu/vt-d: Fix PASID directory pointer coherency")
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Jun 24, 2023
The cited commit adds a compeletion to remove dependency on rtnl
lock. But it causes a deadlock for multiple encapsulations:

 crash> bt ffff8aece8a64000
 PID: 1514557  TASK: ffff8aece8a64000  CPU: 3    COMMAND: "tc"
  #0 [ffffa6d14183f368] __schedule at ffffffffb8ba7f45
  #1 [ffffa6d14183f3f8] schedule at ffffffffb8ba8418
  #2 [ffffa6d14183f418] schedule_preempt_disabled at ffffffffb8ba8898
  #3 [ffffa6d14183f428] __mutex_lock at ffffffffb8baa7f8
  #4 [ffffa6d14183f4d0] mutex_lock_nested at ffffffffb8baabeb
  #5 [ffffa6d14183f4e0] mlx5e_attach_encap at ffffffffc0f48c17 [mlx5_core]
  #6 [ffffa6d14183f628] mlx5e_tc_add_fdb_flow at ffffffffc0f39680 [mlx5_core]
  #7 [ffffa6d14183f688] __mlx5e_add_fdb_flow at ffffffffc0f3b636 [mlx5_core]
  #8 [ffffa6d14183f6f0] mlx5e_tc_add_flow at ffffffffc0f3bcdf [mlx5_core]
  #9 [ffffa6d14183f728] mlx5e_configure_flower at ffffffffc0f3c1d1 [mlx5_core]
 #10 [ffffa6d14183f790] mlx5e_rep_setup_tc_cls_flower at ffffffffc0f3d529 [mlx5_core]
 #11 [ffffa6d14183f7a0] mlx5e_rep_setup_tc_cb at ffffffffc0f3d714 [mlx5_core]
 #12 [ffffa6d14183f7b0] tc_setup_cb_add at ffffffffb8931bb8
 #13 [ffffa6d14183f810] fl_hw_replace_filter at ffffffffc0dae901 [cls_flower]
 #14 [ffffa6d14183f8d8] fl_change at ffffffffc0db5c57 [cls_flower]
 #15 [ffffa6d14183f970] tc_new_tfilter at ffffffffb8936047
 #16 [ffffa6d14183fac8] rtnetlink_rcv_msg at ffffffffb88c7c31
 #17 [ffffa6d14183fb50] netlink_rcv_skb at ffffffffb8942853
 #18 [ffffa6d14183fbc0] rtnetlink_rcv at ffffffffb88c1835
 #19 [ffffa6d14183fbd0] netlink_unicast at ffffffffb8941f27
 #20 [ffffa6d14183fc18] netlink_sendmsg at ffffffffb8942245
 #21 [ffffa6d14183fc98] sock_sendmsg at ffffffffb887d482
 #22 [ffffa6d14183fcb8] ____sys_sendmsg at ffffffffb887d81a
 #23 [ffffa6d14183fd38] ___sys_sendmsg at ffffffffb88806e2
 #24 [ffffa6d14183fe90] __sys_sendmsg at ffffffffb88807a2
 #25 [ffffa6d14183ff28] __x64_sys_sendmsg at ffffffffb888080f
 #26 [ffffa6d14183ff38] do_syscall_64 at ffffffffb8b9b6a8
 #27 [ffffa6d14183ff50] entry_SYSCALL_64_after_hwframe at ffffffffb8c0007c
 crash> bt 0xffff8aeb07544000
 PID: 1110766  TASK: ffff8aeb07544000  CPU: 0    COMMAND: "kworker/u20:9"
  #0 [ffffa6d14e6b7bd8] __schedule at ffffffffb8ba7f45
  #1 [ffffa6d14e6b7c68] schedule at ffffffffb8ba8418
  #2 [ffffa6d14e6b7c88] schedule_timeout at ffffffffb8baef88
  #3 [ffffa6d14e6b7d10] wait_for_completion at ffffffffb8ba968b
  #4 [ffffa6d14e6b7d60] mlx5e_take_all_encap_flows at ffffffffc0f47ec4 [mlx5_core]
  #5 [ffffa6d14e6b7da0] mlx5e_rep_update_flows at ffffffffc0f3e734 [mlx5_core]
  #6 [ffffa6d14e6b7df8] mlx5e_rep_neigh_update at ffffffffc0f400bb [mlx5_core]
  #7 [ffffa6d14e6b7e50] process_one_work at ffffffffb80acc9c
  #8 [ffffa6d14e6b7ed0] worker_thread at ffffffffb80ad012
  #9 [ffffa6d14e6b7f10] kthread at ffffffffb80b615d
 #10 [ffffa6d14e6b7f50] ret_from_fork at ffffffffb8001b2f

After the first encap is attached, flow will be added to encap
entry's flows list. If neigh update is running at this time, the
following encaps of the flow can't hold the encap_tbl_lock and
sleep. If neigh update thread is waiting for that flow's init_done,
deadlock happens.

Fix it by holding lock outside of the for loop. If neigh update is
running, prevent encap flows from offloading. Since the lock is held
outside of the for loop, concurrent creation of encap entries is not
allowed. So remove unnecessary wait_for_completion call for res_ready.

Fixes: 95435ad ("net/mlx5e: Only access fully initialized flows in neigh update")
Signed-off-by: Chris Mi <cmi@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
frank-w pushed a commit that referenced this pull request Jun 26, 2023
Sebastian reports that commit 1c913a1 ("KVM: arm64: Iterate
arm_pmus list to probe for default PMU") introduced the following splat
with CONFIG_DEBUG_PREEMPT enabled:

[70506.110187] BUG: using smp_processor_id() in preemptible [00000000] code: qemu-system-aar/3078242
[70506.119077] caller is debug_smp_processor_id+0x20/0x30
[70506.124229] CPU: 129 PID: 3078242 Comm: qemu-system-aar Tainted: G        W          6.4.0-rc5 #25
[70506.133176] Hardware name: GIGABYTE R181-T92-00/MT91-FS4-00, BIOS F34 08/13/2020
[70506.140559] Call trace:
[70506.142993]  dump_backtrace+0xa4/0x130
[70506.146737]  show_stack+0x20/0x38
[70506.150040]  dump_stack_lvl+0x48/0x60
[70506.153704]  dump_stack+0x18/0x28
[70506.157007]  check_preemption_disabled+0xe4/0x108
[70506.161701]  debug_smp_processor_id+0x20/0x30
[70506.166046]  kvm_arm_pmu_v3_set_attr+0x460/0x628
[70506.170662]  kvm_arm_vcpu_arch_set_attr+0x88/0xd8
[70506.175363]  kvm_arch_vcpu_ioctl+0x258/0x4a8
[70506.179632]  kvm_vcpu_ioctl+0x32c/0x6b8
[70506.183465]  __arm64_sys_ioctl+0xb4/0x100
[70506.187467]  invoke_syscall+0x78/0x108
[70506.191205]  el0_svc_common.constprop.0+0x4c/0x100
[70506.195984]  do_el0_svc+0x34/0x50
[70506.199287]  el0_svc+0x34/0x108
[70506.202416]  el0t_64_sync_handler+0xf4/0x120
[70506.206674]  el0t_64_sync+0x194/0x198

Fix the issue by using the raw variant that bypasses the debug
assertion. While at it, stick all of the nuance and UAPI baggage into a
comment for posterity.

Fixes: 1c913a1 ("KVM: arm64: Iterate arm_pmus list to probe for default PMU")
Reported-by: Sebastian Ott <sebott@redhat.com>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230606184814.456743-1-oliver.upton@linux.dev
frank-w pushed a commit that referenced this pull request Oct 2, 2023
commit 0b0747d upstream.

The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Oct 2, 2023
commit 0b0747d upstream.

The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Oct 26, 2023
commit 0b0747d upstream.

The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Oct 26, 2023
commit 0b0747d upstream.

The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Oct 26, 2023
[ Upstream commit 0b0747d ]

The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request May 9, 2024
KMSAN reported uninit-value access in __ip_make_skb() [1].  __ip_make_skb()
tests HDRINCL to know if the skb has icmphdr. However, HDRINCL can cause a
race condition. If calling setsockopt(2) with IP_HDRINCL changes HDRINCL
while __ip_make_skb() is running, the function will access icmphdr in the
skb even if it is not included. This causes the issue reported by KMSAN.

Check FLOWI_FLAG_KNOWN_NH on fl4->flowi4_flags instead of testing HDRINCL
on the socket.

Also, fl4->fl4_icmp_type and fl4->fl4_icmp_code are not initialized. These
are union in struct flowi4 and are implicitly initialized by
flowi4_init_output(), but we should not rely on specific union layout.

Initialize these explicitly in raw_sendmsg().

[1]
BUG: KMSAN: uninit-value in __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481
 __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481
 ip_finish_skb include/net/ip.h:243 [inline]
 ip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508
 raw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654
 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x274/0x3c0 net/socket.c:745
 __sys_sendto+0x62c/0x7b0 net/socket.c:2191
 __do_sys_sendto net/socket.c:2203 [inline]
 __se_sys_sendto net/socket.c:2199 [inline]
 __x64_sys_sendto+0x130/0x200 net/socket.c:2199
 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3804 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc_node+0x5f6/0xc50 mm/slub.c:3888
 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577
 __alloc_skb+0x35a/0x7c0 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1318 [inline]
 __ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128
 ip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365
 raw_sendmsg+0x22b1/0x2690 net/ipv4/raw.c:648
 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x274/0x3c0 net/socket.c:745
 __sys_sendto+0x62c/0x7b0 net/socket.c:2191
 __do_sys_sendto net/socket.c:2203 [inline]
 __se_sys_sendto net/socket.c:2199 [inline]
 __x64_sys_sendto+0x130/0x200 net/socket.c:2199
 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

CPU: 1 PID: 15709 Comm: syz-executor.7 Not tainted 6.8.0-11567-gb3603fcb79b1 #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014

Fixes: 99e5aca ("ipv4: Fix potential uninit variable access bug in __ip_make_skb()")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Link: https://lore.kernel.org/r/20240430123945.2057348-1-syoshida@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
frank-w pushed a commit that referenced this pull request May 20, 2024
[ Upstream commit fc1092f ]

KMSAN reported uninit-value access in __ip_make_skb() [1].  __ip_make_skb()
tests HDRINCL to know if the skb has icmphdr. However, HDRINCL can cause a
race condition. If calling setsockopt(2) with IP_HDRINCL changes HDRINCL
while __ip_make_skb() is running, the function will access icmphdr in the
skb even if it is not included. This causes the issue reported by KMSAN.

Check FLOWI_FLAG_KNOWN_NH on fl4->flowi4_flags instead of testing HDRINCL
on the socket.

Also, fl4->fl4_icmp_type and fl4->fl4_icmp_code are not initialized. These
are union in struct flowi4 and are implicitly initialized by
flowi4_init_output(), but we should not rely on specific union layout.

Initialize these explicitly in raw_sendmsg().

[1]
BUG: KMSAN: uninit-value in __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481
 __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481
 ip_finish_skb include/net/ip.h:243 [inline]
 ip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508
 raw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654
 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x274/0x3c0 net/socket.c:745
 __sys_sendto+0x62c/0x7b0 net/socket.c:2191
 __do_sys_sendto net/socket.c:2203 [inline]
 __se_sys_sendto net/socket.c:2199 [inline]
 __x64_sys_sendto+0x130/0x200 net/socket.c:2199
 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3804 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc_node+0x5f6/0xc50 mm/slub.c:3888
 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577
 __alloc_skb+0x35a/0x7c0 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1318 [inline]
 __ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128
 ip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365
 raw_sendmsg+0x22b1/0x2690 net/ipv4/raw.c:648
 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x274/0x3c0 net/socket.c:745
 __sys_sendto+0x62c/0x7b0 net/socket.c:2191
 __do_sys_sendto net/socket.c:2203 [inline]
 __se_sys_sendto net/socket.c:2199 [inline]
 __x64_sys_sendto+0x130/0x200 net/socket.c:2199
 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

CPU: 1 PID: 15709 Comm: syz-executor.7 Not tainted 6.8.0-11567-gb3603fcb79b1 #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014

Fixes: 99e5aca ("ipv4: Fix potential uninit variable access bug in __ip_make_skb()")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Link: https://lore.kernel.org/r/20240430123945.2057348-1-syoshida@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Jun 29, 2024
[ Upstream commit 431315a ]

When the rcutorture tests start to exit, the rcu_torture_cleanup() is
invoked to stop kthreads and release resources, if the stall-task
kthreads exist, cpu-stall has started and the rcutorture.stall_cpu
is set to a larger value, the rcu_torture_cleanup() will be blocked
for a long time and the hung-task may occur, this commit therefore
add kthread_should_stop() to the loop of cpu-stall operation, when
rcutorture tests ends, no need to wait for cpu-stall to end, exit
directly.

Use the following command to test:

insmod rcutorture.ko torture_type=srcu fwd_progress=0 stat_interval=4
stall_cpu_block=1 stall_cpu=200 stall_cpu_holdoff=10 read_exit_burst=0
object_debug=1
rmmod rcutorture

[15361.918610] INFO: task rmmod:878 blocked for more than 122 seconds.
[15361.918613]       Tainted: G        W
6.8.0-rc2-yoctodev-standard+ #25
[15361.918615] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[15361.918616] task:rmmod           state:D stack:0     pid:878
tgid:878   ppid:773    flags:0x00004002
[15361.918621] Call Trace:
[15361.918623]  <TASK>
[15361.918626]  __schedule+0xc0d/0x28f0
[15361.918631]  ? __pfx___schedule+0x10/0x10
[15361.918635]  ? rcu_is_watching+0x19/0xb0
[15361.918638]  ? schedule+0x1f6/0x290
[15361.918642]  ? __pfx_lock_release+0x10/0x10
[15361.918645]  ? schedule+0xc9/0x290
[15361.918648]  ? schedule+0xc9/0x290
[15361.918653]  ? trace_preempt_off+0x54/0x100
[15361.918657]  ? schedule+0xc9/0x290
[15361.918661]  schedule+0xd0/0x290
[15361.918665]  schedule_timeout+0x56d/0x7d0
[15361.918669]  ? debug_smp_processor_id+0x1b/0x30
[15361.918672]  ? rcu_is_watching+0x19/0xb0
[15361.918676]  ? __pfx_schedule_timeout+0x10/0x10
[15361.918679]  ? debug_smp_processor_id+0x1b/0x30
[15361.918683]  ? rcu_is_watching+0x19/0xb0
[15361.918686]  ? wait_for_completion+0x179/0x4c0
[15361.918690]  ? __pfx_lock_release+0x10/0x10
[15361.918693]  ? __kasan_check_write+0x18/0x20
[15361.918696]  ? wait_for_completion+0x9d/0x4c0
[15361.918700]  ? _raw_spin_unlock_irq+0x36/0x50
[15361.918703]  ? wait_for_completion+0x179/0x4c0
[15361.918707]  ? _raw_spin_unlock_irq+0x36/0x50
[15361.918710]  ? wait_for_completion+0x179/0x4c0
[15361.918714]  ? trace_preempt_on+0x54/0x100
[15361.918718]  ? wait_for_completion+0x179/0x4c0
[15361.918723]  wait_for_completion+0x181/0x4c0
[15361.918728]  ? __pfx_wait_for_completion+0x10/0x10
[15361.918738]  kthread_stop+0x152/0x470
[15361.918742]  _torture_stop_kthread+0x44/0xc0 [torture
7af7f9cbba28271a10503b653f9e05d518fbc8c3]
[15361.918752]  rcu_torture_cleanup+0x2ac/0xe90 [rcutorture
f2cb1f556ee7956270927183c4c2c7749a336529]
[15361.918766]  ? __pfx_rcu_torture_cleanup+0x10/0x10 [rcutorture
f2cb1f556ee7956270927183c4c2c7749a336529]
[15361.918777]  ? __kasan_check_write+0x18/0x20
[15361.918781]  ? __mutex_unlock_slowpath+0x17c/0x670
[15361.918789]  ? __might_fault+0xcd/0x180
[15361.918793]  ? find_module_all+0x104/0x1d0
[15361.918799]  __x64_sys_delete_module+0x2a4/0x3f0
[15361.918803]  ? __pfx___x64_sys_delete_module+0x10/0x10
[15361.918807]  ? syscall_exit_to_user_mode+0x149/0x280

Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Jun 29, 2024
[ Upstream commit 431315a ]

When the rcutorture tests start to exit, the rcu_torture_cleanup() is
invoked to stop kthreads and release resources, if the stall-task
kthreads exist, cpu-stall has started and the rcutorture.stall_cpu
is set to a larger value, the rcu_torture_cleanup() will be blocked
for a long time and the hung-task may occur, this commit therefore
add kthread_should_stop() to the loop of cpu-stall operation, when
rcutorture tests ends, no need to wait for cpu-stall to end, exit
directly.

Use the following command to test:

insmod rcutorture.ko torture_type=srcu fwd_progress=0 stat_interval=4
stall_cpu_block=1 stall_cpu=200 stall_cpu_holdoff=10 read_exit_burst=0
object_debug=1
rmmod rcutorture

[15361.918610] INFO: task rmmod:878 blocked for more than 122 seconds.
[15361.918613]       Tainted: G        W
6.8.0-rc2-yoctodev-standard+ #25
[15361.918615] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[15361.918616] task:rmmod           state:D stack:0     pid:878
tgid:878   ppid:773    flags:0x00004002
[15361.918621] Call Trace:
[15361.918623]  <TASK>
[15361.918626]  __schedule+0xc0d/0x28f0
[15361.918631]  ? __pfx___schedule+0x10/0x10
[15361.918635]  ? rcu_is_watching+0x19/0xb0
[15361.918638]  ? schedule+0x1f6/0x290
[15361.918642]  ? __pfx_lock_release+0x10/0x10
[15361.918645]  ? schedule+0xc9/0x290
[15361.918648]  ? schedule+0xc9/0x290
[15361.918653]  ? trace_preempt_off+0x54/0x100
[15361.918657]  ? schedule+0xc9/0x290
[15361.918661]  schedule+0xd0/0x290
[15361.918665]  schedule_timeout+0x56d/0x7d0
[15361.918669]  ? debug_smp_processor_id+0x1b/0x30
[15361.918672]  ? rcu_is_watching+0x19/0xb0
[15361.918676]  ? __pfx_schedule_timeout+0x10/0x10
[15361.918679]  ? debug_smp_processor_id+0x1b/0x30
[15361.918683]  ? rcu_is_watching+0x19/0xb0
[15361.918686]  ? wait_for_completion+0x179/0x4c0
[15361.918690]  ? __pfx_lock_release+0x10/0x10
[15361.918693]  ? __kasan_check_write+0x18/0x20
[15361.918696]  ? wait_for_completion+0x9d/0x4c0
[15361.918700]  ? _raw_spin_unlock_irq+0x36/0x50
[15361.918703]  ? wait_for_completion+0x179/0x4c0
[15361.918707]  ? _raw_spin_unlock_irq+0x36/0x50
[15361.918710]  ? wait_for_completion+0x179/0x4c0
[15361.918714]  ? trace_preempt_on+0x54/0x100
[15361.918718]  ? wait_for_completion+0x179/0x4c0
[15361.918723]  wait_for_completion+0x181/0x4c0
[15361.918728]  ? __pfx_wait_for_completion+0x10/0x10
[15361.918738]  kthread_stop+0x152/0x470
[15361.918742]  _torture_stop_kthread+0x44/0xc0 [torture
7af7f9cbba28271a10503b653f9e05d518fbc8c3]
[15361.918752]  rcu_torture_cleanup+0x2ac/0xe90 [rcutorture
f2cb1f556ee7956270927183c4c2c7749a336529]
[15361.918766]  ? __pfx_rcu_torture_cleanup+0x10/0x10 [rcutorture
f2cb1f556ee7956270927183c4c2c7749a336529]
[15361.918777]  ? __kasan_check_write+0x18/0x20
[15361.918781]  ? __mutex_unlock_slowpath+0x17c/0x670
[15361.918789]  ? __might_fault+0xcd/0x180
[15361.918793]  ? find_module_all+0x104/0x1d0
[15361.918799]  __x64_sys_delete_module+0x2a4/0x3f0
[15361.918803]  ? __pfx___x64_sys_delete_module+0x10/0x10
[15361.918807]  ? syscall_exit_to_user_mode+0x149/0x280

Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
BtbN pushed a commit to BtbN/BPI-Router-Linux that referenced this pull request Jul 5, 2024
[ Upstream commit 431315a ]

When the rcutorture tests start to exit, the rcu_torture_cleanup() is
invoked to stop kthreads and release resources, if the stall-task
kthreads exist, cpu-stall has started and the rcutorture.stall_cpu
is set to a larger value, the rcu_torture_cleanup() will be blocked
for a long time and the hung-task may occur, this commit therefore
add kthread_should_stop() to the loop of cpu-stall operation, when
rcutorture tests ends, no need to wait for cpu-stall to end, exit
directly.

Use the following command to test:

insmod rcutorture.ko torture_type=srcu fwd_progress=0 stat_interval=4
stall_cpu_block=1 stall_cpu=200 stall_cpu_holdoff=10 read_exit_burst=0
object_debug=1
rmmod rcutorture

[15361.918610] INFO: task rmmod:878 blocked for more than 122 seconds.
[15361.918613]       Tainted: G        W
6.8.0-rc2-yoctodev-standard+ frank-w#25
[15361.918615] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[15361.918616] task:rmmod           state:D stack:0     pid:878
tgid:878   ppid:773    flags:0x00004002
[15361.918621] Call Trace:
[15361.918623]  <TASK>
[15361.918626]  __schedule+0xc0d/0x28f0
[15361.918631]  ? __pfx___schedule+0x10/0x10
[15361.918635]  ? rcu_is_watching+0x19/0xb0
[15361.918638]  ? schedule+0x1f6/0x290
[15361.918642]  ? __pfx_lock_release+0x10/0x10
[15361.918645]  ? schedule+0xc9/0x290
[15361.918648]  ? schedule+0xc9/0x290
[15361.918653]  ? trace_preempt_off+0x54/0x100
[15361.918657]  ? schedule+0xc9/0x290
[15361.918661]  schedule+0xd0/0x290
[15361.918665]  schedule_timeout+0x56d/0x7d0
[15361.918669]  ? debug_smp_processor_id+0x1b/0x30
[15361.918672]  ? rcu_is_watching+0x19/0xb0
[15361.918676]  ? __pfx_schedule_timeout+0x10/0x10
[15361.918679]  ? debug_smp_processor_id+0x1b/0x30
[15361.918683]  ? rcu_is_watching+0x19/0xb0
[15361.918686]  ? wait_for_completion+0x179/0x4c0
[15361.918690]  ? __pfx_lock_release+0x10/0x10
[15361.918693]  ? __kasan_check_write+0x18/0x20
[15361.918696]  ? wait_for_completion+0x9d/0x4c0
[15361.918700]  ? _raw_spin_unlock_irq+0x36/0x50
[15361.918703]  ? wait_for_completion+0x179/0x4c0
[15361.918707]  ? _raw_spin_unlock_irq+0x36/0x50
[15361.918710]  ? wait_for_completion+0x179/0x4c0
[15361.918714]  ? trace_preempt_on+0x54/0x100
[15361.918718]  ? wait_for_completion+0x179/0x4c0
[15361.918723]  wait_for_completion+0x181/0x4c0
[15361.918728]  ? __pfx_wait_for_completion+0x10/0x10
[15361.918738]  kthread_stop+0x152/0x470
[15361.918742]  _torture_stop_kthread+0x44/0xc0 [torture
7af7f9cbba28271a10503b653f9e05d518fbc8c3]
[15361.918752]  rcu_torture_cleanup+0x2ac/0xe90 [rcutorture
f2cb1f556ee7956270927183c4c2c7749a336529]
[15361.918766]  ? __pfx_rcu_torture_cleanup+0x10/0x10 [rcutorture
f2cb1f556ee7956270927183c4c2c7749a336529]
[15361.918777]  ? __kasan_check_write+0x18/0x20
[15361.918781]  ? __mutex_unlock_slowpath+0x17c/0x670
[15361.918789]  ? __might_fault+0xcd/0x180
[15361.918793]  ? find_module_all+0x104/0x1d0
[15361.918799]  __x64_sys_delete_module+0x2a4/0x3f0
[15361.918803]  ? __pfx___x64_sys_delete_module+0x10/0x10
[15361.918807]  ? syscall_exit_to_user_mode+0x149/0x280

Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
BtbN pushed a commit to BtbN/BPI-Router-Linux that referenced this pull request Jul 5, 2024
[ Upstream commit e3f02f3 ]

Currently, the ionic_run_xdp() doesn't handle multi-buffer packets
properly for XDP_TX and XDP_REDIRECT.
When a jumbo frame is received, the ionic_run_xdp() first makes xdp
frame with all necessary pages in the rx descriptor.
And if the action is either XDP_TX or XDP_REDIRECT, it should unmap
dma-mapping and reset page pointer to NULL for all pages, not only the
first page.
But it doesn't for SG pages. So, SG pages unexpectedly will be reused.
It eventually causes kernel panic.

Oops: general protection fault, probably for non-canonical address 0x504f4e4dbebc64ff: 0000 [frank-w#1] PREEMPT SMP NOPTI
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 6.10.0-rc3+ frank-w#25
RIP: 0010:xdp_return_frame+0x42/0x90
Code: 01 75 12 5b 4c 89 e6 5d 31 c9 41 5c 31 d2 41 5d e9 73 fd ff ff 44 8b 6b 20 0f b7 43 0a 49 81 ed 68 01 00 00 49 29 c5 49 01 fd <41> 80 7d0
RSP: 0018:ffff99d00122ce08 EFLAGS: 00010202
RAX: 0000000000005453 RBX: ffff8d325f904000 RCX: 0000000000000001
RDX: 00000000670e1000 RSI: 000000011f90d000 RDI: 504f4e4d4c4b4a49
RBP: ffff99d003907740 R08: 0000000000000000 R09: 0000000000000000
R10: 000000011f90d000 R11: 0000000000000000 R12: ffff8d325f904010
R13: 504f4e4dbebc64fd R14: ffff8d3242b070c8 R15: ffff99d0039077c0
FS:  0000000000000000(0000) GS:ffff8d399f780000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f41f6c85e38 CR3: 000000037ac30000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
 <IRQ>
 ? die_addr+0x33/0x90
 ? exc_general_protection+0x251/0x2f0
 ? asm_exc_general_protection+0x22/0x30
 ? xdp_return_frame+0x42/0x90
 ionic_tx_clean+0x211/0x280 [ionic 15881354510e6a9c655c59c54812b319ed2cd015]
 ionic_tx_cq_service+0xd3/0x210 [ionic 15881354510e6a9c655c59c54812b319ed2cd015]
 ionic_txrx_napi+0x41/0x1b0 [ionic 15881354510e6a9c655c59c54812b319ed2cd015]
 __napi_poll.constprop.0+0x29/0x1b0
 net_rx_action+0x2c4/0x350
 handle_softirqs+0xf4/0x320
 irq_exit_rcu+0x78/0xa0
 common_interrupt+0x77/0x90

Fixes: 5377805 ("ionic: implement xdp frags support")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Jul 17, 2024
Currently, the ionic_run_xdp() doesn't handle multi-buffer packets
properly for XDP_TX and XDP_REDIRECT.
When a jumbo frame is received, the ionic_run_xdp() first makes xdp
frame with all necessary pages in the rx descriptor.
And if the action is either XDP_TX or XDP_REDIRECT, it should unmap
dma-mapping and reset page pointer to NULL for all pages, not only the
first page.
But it doesn't for SG pages. So, SG pages unexpectedly will be reused.
It eventually causes kernel panic.

Oops: general protection fault, probably for non-canonical address 0x504f4e4dbebc64ff: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 6.10.0-rc3+ #25
RIP: 0010:xdp_return_frame+0x42/0x90
Code: 01 75 12 5b 4c 89 e6 5d 31 c9 41 5c 31 d2 41 5d e9 73 fd ff ff 44 8b 6b 20 0f b7 43 0a 49 81 ed 68 01 00 00 49 29 c5 49 01 fd <41> 80 7d0
RSP: 0018:ffff99d00122ce08 EFLAGS: 00010202
RAX: 0000000000005453 RBX: ffff8d325f904000 RCX: 0000000000000001
RDX: 00000000670e1000 RSI: 000000011f90d000 RDI: 504f4e4d4c4b4a49
RBP: ffff99d003907740 R08: 0000000000000000 R09: 0000000000000000
R10: 000000011f90d000 R11: 0000000000000000 R12: ffff8d325f904010
R13: 504f4e4dbebc64fd R14: ffff8d3242b070c8 R15: ffff99d0039077c0
FS:  0000000000000000(0000) GS:ffff8d399f780000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f41f6c85e38 CR3: 000000037ac30000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
 <IRQ>
 ? die_addr+0x33/0x90
 ? exc_general_protection+0x251/0x2f0
 ? asm_exc_general_protection+0x22/0x30
 ? xdp_return_frame+0x42/0x90
 ionic_tx_clean+0x211/0x280 [ionic 15881354510e6a9c655c59c54812b319ed2cd015]
 ionic_tx_cq_service+0xd3/0x210 [ionic 15881354510e6a9c655c59c54812b319ed2cd015]
 ionic_txrx_napi+0x41/0x1b0 [ionic 15881354510e6a9c655c59c54812b319ed2cd015]
 __napi_poll.constprop.0+0x29/0x1b0
 net_rx_action+0x2c4/0x350
 handle_softirqs+0xf4/0x320
 irq_exit_rcu+0x78/0xa0
 common_interrupt+0x77/0x90

Fixes: 5377805 ("ionic: implement xdp frags support")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
frank-w pushed a commit that referenced this pull request Aug 11, 2024
[ Upstream commit 431315a ]

When the rcutorture tests start to exit, the rcu_torture_cleanup() is
invoked to stop kthreads and release resources, if the stall-task
kthreads exist, cpu-stall has started and the rcutorture.stall_cpu
is set to a larger value, the rcu_torture_cleanup() will be blocked
for a long time and the hung-task may occur, this commit therefore
add kthread_should_stop() to the loop of cpu-stall operation, when
rcutorture tests ends, no need to wait for cpu-stall to end, exit
directly.

Use the following command to test:

insmod rcutorture.ko torture_type=srcu fwd_progress=0 stat_interval=4
stall_cpu_block=1 stall_cpu=200 stall_cpu_holdoff=10 read_exit_burst=0
object_debug=1
rmmod rcutorture

[15361.918610] INFO: task rmmod:878 blocked for more than 122 seconds.
[15361.918613]       Tainted: G        W
6.8.0-rc2-yoctodev-standard+ #25
[15361.918615] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[15361.918616] task:rmmod           state:D stack:0     pid:878
tgid:878   ppid:773    flags:0x00004002
[15361.918621] Call Trace:
[15361.918623]  <TASK>
[15361.918626]  __schedule+0xc0d/0x28f0
[15361.918631]  ? __pfx___schedule+0x10/0x10
[15361.918635]  ? rcu_is_watching+0x19/0xb0
[15361.918638]  ? schedule+0x1f6/0x290
[15361.918642]  ? __pfx_lock_release+0x10/0x10
[15361.918645]  ? schedule+0xc9/0x290
[15361.918648]  ? schedule+0xc9/0x290
[15361.918653]  ? trace_preempt_off+0x54/0x100
[15361.918657]  ? schedule+0xc9/0x290
[15361.918661]  schedule+0xd0/0x290
[15361.918665]  schedule_timeout+0x56d/0x7d0
[15361.918669]  ? debug_smp_processor_id+0x1b/0x30
[15361.918672]  ? rcu_is_watching+0x19/0xb0
[15361.918676]  ? __pfx_schedule_timeout+0x10/0x10
[15361.918679]  ? debug_smp_processor_id+0x1b/0x30
[15361.918683]  ? rcu_is_watching+0x19/0xb0
[15361.918686]  ? wait_for_completion+0x179/0x4c0
[15361.918690]  ? __pfx_lock_release+0x10/0x10
[15361.918693]  ? __kasan_check_write+0x18/0x20
[15361.918696]  ? wait_for_completion+0x9d/0x4c0
[15361.918700]  ? _raw_spin_unlock_irq+0x36/0x50
[15361.918703]  ? wait_for_completion+0x179/0x4c0
[15361.918707]  ? _raw_spin_unlock_irq+0x36/0x50
[15361.918710]  ? wait_for_completion+0x179/0x4c0
[15361.918714]  ? trace_preempt_on+0x54/0x100
[15361.918718]  ? wait_for_completion+0x179/0x4c0
[15361.918723]  wait_for_completion+0x181/0x4c0
[15361.918728]  ? __pfx_wait_for_completion+0x10/0x10
[15361.918738]  kthread_stop+0x152/0x470
[15361.918742]  _torture_stop_kthread+0x44/0xc0 [torture
7af7f9cbba28271a10503b653f9e05d518fbc8c3]
[15361.918752]  rcu_torture_cleanup+0x2ac/0xe90 [rcutorture
f2cb1f556ee7956270927183c4c2c7749a336529]
[15361.918766]  ? __pfx_rcu_torture_cleanup+0x10/0x10 [rcutorture
f2cb1f556ee7956270927183c4c2c7749a336529]
[15361.918777]  ? __kasan_check_write+0x18/0x20
[15361.918781]  ? __mutex_unlock_slowpath+0x17c/0x670
[15361.918789]  ? __might_fault+0xcd/0x180
[15361.918793]  ? find_module_all+0x104/0x1d0
[15361.918799]  __x64_sys_delete_module+0x2a4/0x3f0
[15361.918803]  ? __pfx___x64_sys_delete_module+0x10/0x10
[15361.918807]  ? syscall_exit_to_user_mode+0x149/0x280

Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frank-w pushed a commit that referenced this pull request Nov 3, 2024
A dentry leak may be caused when a lookup cookie and a cull are concurrent:

            P1             |             P2
-----------------------------------------------------------
cachefiles_lookup_cookie
  cachefiles_look_up_object
    lookup_one_positive_unlocked
     // get dentry
                            cachefiles_cull
                              inode->i_flags |= S_KERNEL_FILE;
    cachefiles_open_file
      cachefiles_mark_inode_in_use
        __cachefiles_mark_inode_in_use
          can_use = false
          if (!(inode->i_flags & S_KERNEL_FILE))
            can_use = true
	  return false
        return false
        // Returns an error but doesn't put dentry

After that the following WARNING will be triggered when the backend folder
is umounted:

==================================================================
BUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img}  still in use (1) [unmount of ext4 sda]
WARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70
CPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25
RIP: 0010:umount_check+0x5d/0x70
Call Trace:
 <TASK>
 d_walk+0xda/0x2b0
 do_one_tree+0x20/0x40
 shrink_dcache_for_umount+0x2c/0x90
 generic_shutdown_super+0x20/0x160
 kill_block_super+0x1a/0x40
 ext4_kill_sb+0x22/0x40
 deactivate_locked_super+0x35/0x80
 cleanup_mnt+0x104/0x160
==================================================================

Whether cachefiles_open_file() returns true or false, the reference count
obtained by lookup_positive_unlocked() in cachefiles_look_up_object()
should be released.

Therefore release that reference count in cachefiles_look_up_object() to
fix the above issue and simplify the code.

Fixes: 1f08c92 ("cachefiles: Implement backing file wrangling")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240829083409.3788142-1-libaokun@huaweicloud.com
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
BtbN pushed a commit to BtbN/BPI-Router-Linux that referenced this pull request Nov 9, 2024
commit da6ef2d upstream.

A dentry leak may be caused when a lookup cookie and a cull are concurrent:

            P1             |             P2
-----------------------------------------------------------
cachefiles_lookup_cookie
  cachefiles_look_up_object
    lookup_one_positive_unlocked
     // get dentry
                            cachefiles_cull
                              inode->i_flags |= S_KERNEL_FILE;
    cachefiles_open_file
      cachefiles_mark_inode_in_use
        __cachefiles_mark_inode_in_use
          can_use = false
          if (!(inode->i_flags & S_KERNEL_FILE))
            can_use = true
	  return false
        return false
        // Returns an error but doesn't put dentry

After that the following WARNING will be triggered when the backend folder
is umounted:

==================================================================
BUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img}  still in use (1) [unmount of ext4 sda]
WARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70
CPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty frank-w#25
RIP: 0010:umount_check+0x5d/0x70
Call Trace:
 <TASK>
 d_walk+0xda/0x2b0
 do_one_tree+0x20/0x40
 shrink_dcache_for_umount+0x2c/0x90
 generic_shutdown_super+0x20/0x160
 kill_block_super+0x1a/0x40
 ext4_kill_sb+0x22/0x40
 deactivate_locked_super+0x35/0x80
 cleanup_mnt+0x104/0x160
==================================================================

Whether cachefiles_open_file() returns true or false, the reference count
obtained by lookup_positive_unlocked() in cachefiles_look_up_object()
should be released.

Therefore release that reference count in cachefiles_look_up_object() to
fix the above issue and simplify the code.

Fixes: 1f08c92 ("cachefiles: Implement backing file wrangling")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240829083409.3788142-1-libaokun@huaweicloud.com
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frank-w pushed a commit that referenced this pull request Dec 6, 2024
commit da6ef2d upstream.

A dentry leak may be caused when a lookup cookie and a cull are concurrent:

            P1             |             P2
-----------------------------------------------------------
cachefiles_lookup_cookie
  cachefiles_look_up_object
    lookup_one_positive_unlocked
     // get dentry
                            cachefiles_cull
                              inode->i_flags |= S_KERNEL_FILE;
    cachefiles_open_file
      cachefiles_mark_inode_in_use
        __cachefiles_mark_inode_in_use
          can_use = false
          if (!(inode->i_flags & S_KERNEL_FILE))
            can_use = true
	  return false
        return false
        // Returns an error but doesn't put dentry

After that the following WARNING will be triggered when the backend folder
is umounted:

==================================================================
BUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img}  still in use (1) [unmount of ext4 sda]
WARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70
CPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25
RIP: 0010:umount_check+0x5d/0x70
Call Trace:
 <TASK>
 d_walk+0xda/0x2b0
 do_one_tree+0x20/0x40
 shrink_dcache_for_umount+0x2c/0x90
 generic_shutdown_super+0x20/0x160
 kill_block_super+0x1a/0x40
 ext4_kill_sb+0x22/0x40
 deactivate_locked_super+0x35/0x80
 cleanup_mnt+0x104/0x160
==================================================================

Whether cachefiles_open_file() returns true or false, the reference count
obtained by lookup_positive_unlocked() in cachefiles_look_up_object()
should be released.

Therefore release that reference count in cachefiles_look_up_object() to
fix the above issue and simplify the code.

Fixes: 1f08c92 ("cachefiles: Implement backing file wrangling")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240829083409.3788142-1-libaokun@huaweicloud.com
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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