[lineage-17.1] Android Security Bulletin 2020-08 #3

derfelot · 2020-08-03T23:34:47Z

No description provided.

When host sends ft assoc response to supplicant, it allocates a buffer of fixed size and copies a variable length of assoc response IEs to this fixed sized buffer. There is a possibility of OOB write to the allocated buffer if the assoc response IEs length is greater than the allocated buffer size. To avoid above issue validate the assoc response IEs length with the allocated buffer size before data copy to the buffer. Change-ID: Ife9c2071a8cc4a2918b9f349f4024478f94b2d78 CRs-Fixed: 2575144

In function rrm_fill_beacon_ies, do while loop is checked for BcnNumIes if it is greater than IE length 0. Fix the check to be greater than 2 as the first two bytes is IE header(element ID and IE length fields both 1 byte each.) Change-Id: I11e5de481cd49a22acafee938fbe73f839f5b0e4 CRs-Fixed: 2626729

derfelot · 2020-08-03T23:35:10Z

With this, all should be good from kernels side for ASB 2020-08

[ Upstream commit e24c644 ] I compiled with AddressSanitizer and I had these memory leaks while I was using the tep_parse_format function: Direct leak of 28 byte(s) in 4 object(s) allocated from: #0 0x7fb07db49ffe in __interceptor_realloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dffe) whatawurst#1 0x7fb07a724228 in extend_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:985 whatawurst#2 0x7fb07a724c21 in __read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1140 whatawurst#3 0x7fb07a724f78 in read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1206 whatawurst#4 0x7fb07a725191 in __read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1291 whatawurst#5 0x7fb07a7251df in read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1299 whatawurst#6 0x7fb07a72e6c8 in process_dynamic_array_len /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:2849 whatawurst#7 0x7fb07a7304b8 in process_function /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3161 whatawurst#8 0x7fb07a730900 in process_arg_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3207 whatawurst#9 0x7fb07a727c0b in process_arg /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1786 whatawurst#10 0x7fb07a731080 in event_read_print_args /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3285 whatawurst#11 0x7fb07a731722 in event_read_print /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3369 whatawurst#12 0x7fb07a740054 in __tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6335 whatawurst#13 0x7fb07a74047a in __parse_event /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6389 whatawurst#14 0x7fb07a740536 in tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6431 whatawurst#15 0x7fb07a785acf in parse_event ../../../src/fs-src/fs.c:251 whatawurst#16 0x7fb07a785ccd in parse_systems ../../../src/fs-src/fs.c:284 whatawurst#17 0x7fb07a786fb3 in read_metadata ../../../src/fs-src/fs.c:593 whatawurst#18 0x7fb07a78760e in ftrace_fs_source_init ../../../src/fs-src/fs.c:727 whatawurst#19 0x7fb07d90c19c in add_component_with_init_method_data ../../../../src/lib/graph/graph.c:1048 whatawurst#20 0x7fb07d90c87b in add_source_component_with_initialize_method_data ../../../../src/lib/graph/graph.c:1127 whatawurst#21 0x7fb07d90c92a in bt_graph_add_source_component ../../../../src/lib/graph/graph.c:1152 whatawurst#22 0x55db11aa632e in cmd_run_ctx_create_components_from_config_components ../../../src/cli/babeltrace2.c:2252 whatawurst#23 0x55db11aa6fda in cmd_run_ctx_create_components ../../../src/cli/babeltrace2.c:2347 whatawurst#24 0x55db11aa780c in cmd_run ../../../src/cli/babeltrace2.c:2461 whatawurst#25 0x55db11aa8a7d in main ../../../src/cli/babeltrace2.c:2673 whatawurst#26 0x7fb07d5460b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2) The token variable in the process_dynamic_array_len function is allocated in the read_expect_type function, but is not freed before calling the read_token function. Free the token variable before calling read_token in order to plug the leak. Signed-off-by: Philippe Duplessis-Guindon <pduplessis@efficios.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/linux-trace-devel/20200730150236.5392-1-pduplessis@efficios.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

There appears to be a timing issue where using a divider of 32 breaks the DSS for OMAP36xx despite the TRM stating 32 is a valid number. Through experimentation, it appears that 31 works. This same fix was issued for kernels 4.5+. However, between kernels 4.4 and 4.5, the directory structure was changed when the dss directory was moved inside the omapfb directory. That broke the patch on kernels older than 4.5, because it didn't permit the patch to apply cleanly for 4.4 and older. A similar patch was applied to the 3.16 kernel already, but not to 4.4. Commit 4b911101a5cd ("drm/omap: fix max fclk divider for omap36xx") is on the 3.16 stable branch with notes from Ben about the path change. Since this was applied for 3.16 already, this patch is for kernels 3.17 through 4.4 only. Fixes: f7018c2 ("video: move fbdev to drivers/video/fbdev") Cc: <stable@vger.kernel.org> whatawurst#3.17 - 4.4 CC: <tomi.valkeinen@ti.com> Signed-off-by: Adam Ford <aford173@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit d26383d ] The following leaks were detected by ASAN: Indirect leak of 360 byte(s) in 9 object(s) allocated from: #0 0x7fecc305180e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e) whatawurst#1 0x560578f6dce5 in perf_pmu__new_format util/pmu.c:1333 whatawurst#2 0x560578f752fc in perf_pmu_parse util/pmu.y:59 whatawurst#3 0x560578f6a8b7 in perf_pmu__format_parse util/pmu.c:73 whatawurst#4 0x560578e07045 in test__pmu tests/pmu.c:155 whatawurst#5 0x560578de109b in run_test tests/builtin-test.c:410 whatawurst#6 0x560578de109b in test_and_print tests/builtin-test.c:440 whatawurst#7 0x560578de401a in __cmd_test tests/builtin-test.c:661 whatawurst#8 0x560578de401a in cmd_test tests/builtin-test.c:807 whatawurst#9 0x560578e49354 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 whatawurst#10 0x560578ce71a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 whatawurst#11 0x560578ce71a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 whatawurst#12 0x560578ce71a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 whatawurst#13 0x7fecc2b7acc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: cff7f95 ("perf tests: Move pmu tests into separate object") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200915031819.386559-12-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit b872d06 ] The vfio_pci_release call will free and clear the error and request eventfd ctx while these ctx could be in use at the same time in the function like vfio_pci_request, and it's expected to protect them under the vdev->igate mutex, which is missing in vfio_pci_release. This issue is introduced since commit 1518ac2 ("vfio/pci: fix memory leaks of eventfd ctx"),and since commit 5c5866c ("vfio/pci: Clear error and request eventfd ctx after releasing"), it's very easily to trigger the kernel panic like this: [ 9513.904346] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 [ 9513.913091] Mem abort info: [ 9513.915871] ESR = 0x96000006 [ 9513.918912] EC = 0x25: DABT (current EL), IL = 32 bits [ 9513.924198] SET = 0, FnV = 0 [ 9513.927238] EA = 0, S1PTW = 0 [ 9513.930364] Data abort info: [ 9513.933231] ISV = 0, ISS = 0x00000006 [ 9513.937048] CM = 0, WnR = 0 [ 9513.940003] user pgtable: 4k pages, 48-bit VAs, pgdp=0000007ec7d12000 [ 9513.946414] [0000000000000008] pgd=0000007ec7d13003, p4d=0000007ec7d13003, pud=0000007ec728c003, pmd=0000000000000000 [ 9513.956975] Internal error: Oops: 96000006 [whatawurst#1] PREEMPT SMP [ 9513.962521] Modules linked in: vfio_pci vfio_virqfd vfio_iommu_type1 vfio hclge hns3 hnae3 [last unloaded: vfio_pci] [ 9513.972998] CPU: 4 PID: 1327 Comm: bash Tainted: G W 5.8.0-rc4+ whatawurst#3 [ 9513.980443] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B270.01 05/08/2020 [ 9513.989274] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--) [ 9513.994827] pc : _raw_spin_lock_irqsave+0x48/0x88 [ 9513.999515] lr : eventfd_signal+0x6c/0x1b0 [ 9514.003591] sp : ffff800038a0b960 [ 9514.006889] x29: ffff800038a0b960 x28: ffff007ef7f4da10 [ 9514.012175] x27: ffff207eefbbfc80 x26: ffffbb7903457000 [ 9514.017462] x25: ffffbb7912191000 x24: ffff007ef7f4d400 [ 9514.022747] x23: ffff20be6e0e4c00 x22: 0000000000000008 [ 9514.028033] x21: 0000000000000000 x20: 0000000000000000 [ 9514.033321] x19: 0000000000000008 x18: 0000000000000000 [ 9514.038606] x17: 0000000000000000 x16: ffffbb7910029328 [ 9514.043893] x15: 0000000000000000 x14: 0000000000000001 [ 9514.049179] x13: 0000000000000000 x12: 0000000000000002 [ 9514.054466] x11: 0000000000000000 x10: 0000000000000a00 [ 9514.059752] x9 : ffff800038a0b840 x8 : ffff007ef7f4de60 [ 9514.065038] x7 : ffff007fffc96690 x6 : fffffe01faffb748 [ 9514.070324] x5 : 0000000000000000 x4 : 0000000000000000 [ 9514.075609] x3 : 0000000000000000 x2 : 0000000000000001 [ 9514.080895] x1 : ffff007ef7f4d400 x0 : 0000000000000000 [ 9514.086181] Call trace: [ 9514.088618] _raw_spin_lock_irqsave+0x48/0x88 [ 9514.092954] eventfd_signal+0x6c/0x1b0 [ 9514.096691] vfio_pci_request+0x84/0xd0 [vfio_pci] [ 9514.101464] vfio_del_group_dev+0x150/0x290 [vfio] [ 9514.106234] vfio_pci_remove+0x30/0x128 [vfio_pci] [ 9514.111007] pci_device_remove+0x48/0x108 [ 9514.115001] device_release_driver_internal+0x100/0x1b8 [ 9514.120200] device_release_driver+0x28/0x38 [ 9514.124452] pci_stop_bus_device+0x68/0xa8 [ 9514.128528] pci_stop_and_remove_bus_device+0x20/0x38 [ 9514.133557] pci_iov_remove_virtfn+0xb4/0x128 [ 9514.137893] sriov_disable+0x3c/0x108 [ 9514.141538] pci_disable_sriov+0x28/0x38 [ 9514.145445] hns3_pci_sriov_configure+0x48/0xb8 [hns3] [ 9514.150558] sriov_numvfs_store+0x110/0x198 [ 9514.154724] dev_attr_store+0x44/0x60 [ 9514.158373] sysfs_kf_write+0x5c/0x78 [ 9514.162018] kernfs_fop_write+0x104/0x210 [ 9514.166010] __vfs_write+0x48/0x90 [ 9514.169395] vfs_write+0xbc/0x1c0 [ 9514.172694] ksys_write+0x74/0x100 [ 9514.176079] __arm64_sys_write+0x24/0x30 [ 9514.179987] el0_svc_common.constprop.4+0x110/0x200 [ 9514.184842] do_el0_svc+0x34/0x98 [ 9514.188144] el0_svc+0x14/0x40 [ 9514.191185] el0_sync_handler+0xb0/0x2d0 [ 9514.195088] el0_sync+0x140/0x180 [ 9514.198389] Code: b9001020 d2800000 52800022 f9800271 (885ffe61) [ 9514.204455] ---[ end trace 648de00c8406465f ]--- [ 9514.212308] note: bash[1327] exited with preempt_count 1 Cc: Qian Cai <cai@lca.pw> Cc: Alex Williamson <alex.williamson@redhat.com> Fixes: 1518ac2 ("vfio/pci: fix memory leaks of eventfd ctx") Signed-off-by: Zeng Tao <prime.zeng@hisilicon.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

Move the loop-invariant calculation of 'cpu' in do_idle() out of the loop body, because the current CPU is always constant. This improves the generated code both on x86-64 and ARM64: x86-64: Before patch (execution in loop): 864: 0f ae e8 lfence 867: 65 8b 05 c2 38 f1 7e mov %gs:0x7ef138c2(%rip),%eax 86e: 89 c0 mov %eax,%eax 870: 48 0f a3 05 68 19 08 bt %rax,0x1081968(%rip) 877: 01 After patch (execution in loop): 872: 0f ae e8 lfence 875: 4c 0f a3 25 63 19 08 bt %r12,0x1081963(%rip) 87c: 01 ARM64: Before patch (execution in loop): c58: d5033d9f dsb ld c5c: d538d080 mrs x0, tpidr_el1 c60: b8606a61 ldr w1, [x19,x0] c64: 1100fc20 add w0, w1, #0x3f c68: 7100003f cmp w1, #0x0 c6c: 1a81b000 csel w0, w0, w1, lt c70: 13067c00 asr w0, w0, whatawurst#6 c74: 93407c00 sxtw x0, w0 c78: f8607a80 ldr x0, [x20,x0,lsl whatawurst#3] c7c: 9ac12401 lsr x1, x0, x1 c80: 36000581 tbz w1, #0, d30 <do_idle+0x128> After patch (execution in loop): c84: d5033d9f dsb ld c88: f9400260 ldr x0, [x19] c8c: ea14001f tst x0, x20 c90: 54000580 b.eq d40 <do_idle+0x138> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> [ Rewrote the title and the changelog. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: huawei.libin@huawei.com Cc: xiexiuqi@huawei.com Link: http://lkml.kernel.org/r/1508930907-107755-1-git-send-email-cj.chengjian@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>

[ Upstream commit 71a174b ] b6da31b "tty: Fix data race in tty_insert_flip_string_fixed_flag" puts tty_flip_buffer_push under port->lock introducing the following possible circular locking dependency: [30129.876566] ====================================================== [30129.876566] WARNING: possible circular locking dependency detected [30129.876567] 5.9.0-rc2+ whatawurst#3 Tainted: G S W [30129.876568] ------------------------------------------------------ [30129.876568] sysrq.sh/1222 is trying to acquire lock: [30129.876569] ffffffff92c39480 (console_owner){....}-{0:0}, at: console_unlock+0x3fe/0xa90 [30129.876572] but task is already holding lock: [30129.876572] ffff888107cb9018 (&pool->lock/1){-.-.}-{2:2}, at: show_workqueue_state.cold.55+0x15b/0x6ca [30129.876576] which lock already depends on the new lock. [30129.876577] the existing dependency chain (in reverse order) is: [30129.876578] -> whatawurst#3 (&pool->lock/1){-.-.}-{2:2}: [30129.876581] _raw_spin_lock+0x30/0x70 [30129.876581] __queue_work+0x1a3/0x10f0 [30129.876582] queue_work_on+0x78/0x80 [30129.876582] pty_write+0x165/0x1e0 [30129.876583] n_tty_write+0x47f/0xf00 [30129.876583] tty_write+0x3d6/0x8d0 [30129.876584] vfs_write+0x1a8/0x650 [30129.876588] -> whatawurst#2 (&port->lock#2){-.-.}-{2:2}: [30129.876590] _raw_spin_lock_irqsave+0x3b/0x80 [30129.876591] tty_port_tty_get+0x1d/0xb0 [30129.876592] tty_port_default_wakeup+0xb/0x30 [30129.876592] serial8250_tx_chars+0x3d6/0x970 [30129.876593] serial8250_handle_irq.part.12+0x216/0x380 [30129.876593] serial8250_default_handle_irq+0x82/0xe0 [30129.876594] serial8250_interrupt+0xdd/0x1b0 [30129.876595] __handle_irq_event_percpu+0xfc/0x850 [30129.876602] -> whatawurst#1 (&port->lock){-.-.}-{2:2}: [30129.876605] _raw_spin_lock_irqsave+0x3b/0x80 [30129.876605] serial8250_console_write+0x12d/0x900 [30129.876606] console_unlock+0x679/0xa90 [30129.876606] register_console+0x371/0x6e0 [30129.876607] univ8250_console_init+0x24/0x27 [30129.876607] console_init+0x2f9/0x45e [30129.876609] -> #0 (console_owner){....}-{0:0}: [30129.876611] __lock_acquire+0x2f70/0x4e90 [30129.876612] lock_acquire+0x1ac/0xad0 [30129.876612] console_unlock+0x460/0xa90 [30129.876613] vprintk_emit+0x130/0x420 [30129.876613] printk+0x9f/0xc5 [30129.876614] show_pwq+0x154/0x618 [30129.876615] show_workqueue_state.cold.55+0x193/0x6ca [30129.876615] __handle_sysrq+0x244/0x460 [30129.876616] write_sysrq_trigger+0x48/0x4a [30129.876616] proc_reg_write+0x1a6/0x240 [30129.876617] vfs_write+0x1a8/0x650 [30129.876619] other info that might help us debug this: [30129.876620] Chain exists of: [30129.876621] console_owner --> &port->lock#2 --> &pool->lock/1 [30129.876625] Possible unsafe locking scenario: [30129.876626] CPU0 CPU1 [30129.876626] ---- ---- [30129.876627] lock(&pool->lock/1); [30129.876628] lock(&port->lock#2); [30129.876630] lock(&pool->lock/1); [30129.876631] lock(console_owner); [30129.876633] *** DEADLOCK *** [30129.876634] 5 locks held by sysrq.sh/1222: [30129.876634] #0: ffff8881d3ce0470 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x359/0x650 [30129.876637] whatawurst#1: ffffffff92c612c0 (rcu_read_lock){....}-{1:2}, at: __handle_sysrq+0x4d/0x460 [30129.876640] whatawurst#2: ffffffff92c612c0 (rcu_read_lock){....}-{1:2}, at: show_workqueue_state+0x5/0xf0 [30129.876642] whatawurst#3: ffff888107cb9018 (&pool->lock/1){-.-.}-{2:2}, at: show_workqueue_state.cold.55+0x15b/0x6ca [30129.876645] whatawurst#4: ffffffff92c39980 (console_lock){+.+.}-{0:0}, at: vprintk_emit+0x123/0x420 [30129.876648] stack backtrace: [30129.876649] CPU: 3 PID: 1222 Comm: sysrq.sh Tainted: G S W 5.9.0-rc2+ whatawurst#3 [30129.876649] Hardware name: Intel Corporation 2012 Client Platform/Emerald Lake 2, BIOS ACRVMBY1.86C.0078.P00.1201161002 01/16/2012 [30129.876650] Call Trace: [30129.876650] dump_stack+0x9d/0xe0 [30129.876651] check_noncircular+0x34f/0x410 [30129.876653] __lock_acquire+0x2f70/0x4e90 [30129.876656] lock_acquire+0x1ac/0xad0 [30129.876658] console_unlock+0x460/0xa90 [30129.876660] vprintk_emit+0x130/0x420 [30129.876660] printk+0x9f/0xc5 [30129.876661] show_pwq+0x154/0x618 [30129.876662] show_workqueue_state.cold.55+0x193/0x6ca [30129.876664] __handle_sysrq+0x244/0x460 [30129.876665] write_sysrq_trigger+0x48/0x4a [30129.876665] proc_reg_write+0x1a6/0x240 [30129.876666] vfs_write+0x1a8/0x650 It looks like the commit was aimed to protect tty_insert_flip_string and there is no need for tty_flip_buffer_push to be under this lock. Fixes: b6da31b ("tty: Fix data race in tty_insert_flip_string_fixed_flag") Signed-off-by: Artem Savkov <asavkov@redhat.com> Acked-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20200902120045.3693075-1-asavkov@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit e773ca7 ] Actually, burst size is equal to '1 << desc->rqcfg.brst_size'. we should use burst size, not desc->rqcfg.brst_size. dma memcpy performance on Rockchip RV1126 @ 1512MHz A7, 1056MHz LPDDR3, 200MHz DMA: dmatest: /# echo dma0chan0 > /sys/module/dmatest/parameters/channel /# echo 4194304 > /sys/module/dmatest/parameters/test_buf_size /# echo 8 > /sys/module/dmatest/parameters/iterations /# echo y > /sys/module/dmatest/parameters/norandom /# echo y > /sys/module/dmatest/parameters/verbose /# echo 1 > /sys/module/dmatest/parameters/run dmatest: dma0chan0-copy0: result whatawurst#1: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result whatawurst#2: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result whatawurst#3: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result whatawurst#4: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result whatawurst#5: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result whatawurst#6: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result whatawurst#7: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result whatawurst#8: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 Before: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 48 iops 200338 KB/s (0) After this patch: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 179 iops 734873 KB/s (0) After this patch and increase dma clk to 400MHz: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 259 iops 1062929 KB/s (0) Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com> Link: https://lore.kernel.org/r/1605326106-55681-1-git-send-email-sugar.zhang@rock-chips.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

commit ca10845 upstream While running btrfs/061, btrfs/073, btrfs/078, or btrfs/178 we hit the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.9.0-rc3+ whatawurst#4 Not tainted ------------------------------------------------------ kswapd0/100 is trying to acquire lock: ffff96ecc22ef4a0 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x330 but task is already holding lock: ffffffff8dd74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> whatawurst#3 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire+0x65/0x80 slab_pre_alloc_hook.constprop.0+0x20/0x200 kmem_cache_alloc+0x37/0x270 alloc_inode+0x82/0xb0 iget_locked+0x10d/0x2c0 kernfs_get_inode+0x1b/0x130 kernfs_get_tree+0x136/0x240 sysfs_get_tree+0x16/0x40 vfs_get_tree+0x28/0xc0 path_mount+0x434/0xc00 __x64_sys_mount+0xe3/0x120 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> whatawurst#2 (kernfs_mutex){+.+.}-{3:3}: __mutex_lock+0x7e/0x7e0 kernfs_add_one+0x23/0x150 kernfs_create_link+0x63/0xa0 sysfs_do_create_link_sd+0x5e/0xd0 btrfs_sysfs_add_devices_dir+0x81/0x130 btrfs_init_new_device+0x67f/0x1250 btrfs_ioctl+0x1ef/0x2e20 __x64_sys_ioctl+0x83/0xb0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> whatawurst#1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __mutex_lock+0x7e/0x7e0 btrfs_chunk_alloc+0x125/0x3a0 find_free_extent+0xdf6/0x1210 btrfs_reserve_extent+0xb3/0x1b0 btrfs_alloc_tree_block+0xb0/0x310 alloc_tree_block_no_bg_flush+0x4a/0x60 __btrfs_cow_block+0x11a/0x530 btrfs_cow_block+0x104/0x220 btrfs_search_slot+0x52e/0x9d0 btrfs_insert_empty_items+0x64/0xb0 btrfs_insert_delayed_items+0x90/0x4f0 btrfs_commit_inode_delayed_items+0x93/0x140 btrfs_log_inode+0x5de/0x2020 btrfs_log_inode_parent+0x429/0xc90 btrfs_log_new_name+0x95/0x9b btrfs_rename2+0xbb9/0x1800 vfs_rename+0x64f/0x9f0 do_renameat2+0x320/0x4e0 __x64_sys_rename+0x1f/0x30 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&delayed_node->mutex){+.+.}-{3:3}: __lock_acquire+0x119c/0x1fc0 lock_acquire+0xa7/0x3d0 __mutex_lock+0x7e/0x7e0 __btrfs_release_delayed_node.part.0+0x3f/0x330 btrfs_evict_inode+0x24c/0x500 evict+0xcf/0x1f0 dispose_list+0x48/0x70 prune_icache_sb+0x44/0x50 super_cache_scan+0x161/0x1e0 do_shrink_slab+0x178/0x3c0 shrink_slab+0x17c/0x290 shrink_node+0x2b2/0x6d0 balance_pgdat+0x30a/0x670 kswapd+0x213/0x4c0 kthread+0x138/0x160 ret_from_fork+0x1f/0x30 other info that might help us debug this: Chain exists of: &delayed_node->mutex --> kernfs_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(kernfs_mutex); lock(fs_reclaim); lock(&delayed_node->mutex); *** DEADLOCK *** 3 locks held by kswapd0/100: #0: ffffffff8dd74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 whatawurst#1: ffffffff8dd65c50 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x115/0x290 whatawurst#2: ffff96ed2ade30e0 (&type->s_umount_key#36){++++}-{3:3}, at: super_cache_scan+0x38/0x1e0 stack backtrace: CPU: 0 PID: 100 Comm: kswapd0 Not tainted 5.9.0-rc3+ whatawurst#4 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack+0x8b/0xb8 check_noncircular+0x12d/0x150 __lock_acquire+0x119c/0x1fc0 lock_acquire+0xa7/0x3d0 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 __mutex_lock+0x7e/0x7e0 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 ? lock_acquire+0xa7/0x3d0 ? find_held_lock+0x2b/0x80 __btrfs_release_delayed_node.part.0+0x3f/0x330 btrfs_evict_inode+0x24c/0x500 evict+0xcf/0x1f0 dispose_list+0x48/0x70 prune_icache_sb+0x44/0x50 super_cache_scan+0x161/0x1e0 do_shrink_slab+0x178/0x3c0 shrink_slab+0x17c/0x290 shrink_node+0x2b2/0x6d0 balance_pgdat+0x30a/0x670 kswapd+0x213/0x4c0 ? _raw_spin_unlock_irqrestore+0x41/0x50 ? add_wait_queue_exclusive+0x70/0x70 ? balance_pgdat+0x670/0x670 kthread+0x138/0x160 ? kthread_create_worker_on_cpu+0x40/0x40 ret_from_fork+0x1f/0x30 This happens because we are holding the chunk_mutex at the time of adding in a new device. However we only need to hold the device_list_mutex, as we're going to iterate over the fs_devices devices. Move the sysfs init stuff outside of the chunk_mutex to get rid of this lockdep splat. CC: stable@vger.kernel.org # 4.4.x: f3cd2c5: btrfs: sysfs, rename device_link add/remove functions CC: stable@vger.kernel.org # 4.4.x Reported-by: David Sterba <dsterba@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [sudip: adjust context] Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 4a9d81c ] If the elem is deleted during be iterated on it, the iteration process will fall into an endless loop. kernel: NMI watchdog: BUG: soft lockup - CPU#4 stuck for 22s! [nfsd:17137] PID: 17137 TASK: ffff8818d93c0000 CPU: 4 COMMAND: "nfsd" [exception RIP: __state_in_grace+76] RIP: ffffffffc00e817c RSP: ffff8818d3aefc98 RFLAGS: 00000246 RAX: ffff881dc0c38298 RBX: ffffffff81b03580 RCX: ffff881dc02c9f50 RDX: ffff881e3fce8500 RSI: 0000000000000001 RDI: ffffffff81b03580 RBP: ffff8818d3aefca0 R8: 0000000000000020 R9: ffff8818d3aefd40 R10: ffff88017fc03800 R11: ffff8818e83933c0 R12: ffff8818d3aefd40 R13: 0000000000000000 R14: ffff8818e8391068 R15: ffff8818fa6e4000 CS: 0010 SS: 0018 #0 [ffff8818d3aefc98] opens_in_grace at ffffffffc00e81e3 [grace] whatawurst#1 [ffff8818d3aefca8] nfs4_preprocess_stateid_op at ffffffffc02a3e6c [nfsd] whatawurst#2 [ffff8818d3aefd18] nfsd4_write at ffffffffc028ed5b [nfsd] whatawurst#3 [ffff8818d3aefd80] nfsd4_proc_compound at ffffffffc0290a0d [nfsd] whatawurst#4 [ffff8818d3aefdd0] nfsd_dispatch at ffffffffc027b800 [nfsd] whatawurst#5 [ffff8818d3aefe08] svc_process_common at ffffffffc02017f3 [sunrpc] whatawurst#6 [ffff8818d3aefe70] svc_process at ffffffffc0201ce3 [sunrpc] whatawurst#7 [ffff8818d3aefe98] nfsd at ffffffffc027b117 [nfsd] whatawurst#8 [ffff8818d3aefec8] kthread at ffffffff810b88c1 whatawurst#9 [ffff8818d3aeff50] ret_from_fork at ffffffff816d1607 The troublemake elem: crash> lock_manager ffff881dc0c38298 struct lock_manager { list = { next = 0xffff881dc0c38298, prev = 0xffff881dc0c38298 }, block_opens = false } Fixes: c87fb4a ("lockd: NLM grace period shouldn't block NFSv4 opens") Signed-off-by: Cheng Lin <cheng.lin130@zte.com.cn> Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

Move the loop-invariant calculation of 'cpu' in do_idle() out of the loop body, because the current CPU is always constant. This improves the generated code both on x86-64 and ARM64: x86-64: Before patch (execution in loop): 864: 0f ae e8 lfence 867: 65 8b 05 c2 38 f1 7e mov %gs:0x7ef138c2(%rip),%eax 86e: 89 c0 mov %eax,%eax 870: 48 0f a3 05 68 19 08 bt %rax,0x1081968(%rip) 877: 01 After patch (execution in loop): 872: 0f ae e8 lfence 875: 4c 0f a3 25 63 19 08 bt %r12,0x1081963(%rip) 87c: 01 ARM64: Before patch (execution in loop): c58: d5033d9f dsb ld c5c: d538d080 mrs x0, tpidr_el1 c60: b8606a61 ldr w1, [x19,x0] c64: 1100fc20 add w0, w1, #0x3f c68: 7100003f cmp w1, #0x0 c6c: 1a81b000 csel w0, w0, w1, lt c70: 13067c00 asr w0, w0, whatawurst#6 c74: 93407c00 sxtw x0, w0 c78: f8607a80 ldr x0, [x20,x0,lsl whatawurst#3] c7c: 9ac12401 lsr x1, x0, x1 c80: 36000581 tbz w1, #0, d30 <do_idle+0x128> After patch (execution in loop): c84: d5033d9f dsb ld c88: f9400260 ldr x0, [x19] c8c: ea14001f tst x0, x20 c90: 54000580 b.eq d40 <do_idle+0x138> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> [ Rewrote the title and the changelog. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: huawei.libin@huawei.com Cc: xiexiuqi@huawei.com Link: http://lkml.kernel.org/r/1508930907-107755-1-git-send-email-cj.chengjian@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>

Currently, smp_processor_id() is used to fetch the current CPU in cpu_idle_loop(). Every time the idle thread runs, it fetches the current CPU using smp_processor_id(). Since the idle thread is per CPU, the current CPU is constant, so we can lift the load out of the loop, saving execution cycles/time in the loop. x86-64: Before patch (execution in loop): 148: 0f ae e8 lfence 14b: 65 8b 04 25 00 00 00 00 mov %gs:0x0,%eax 152: 00 153: 89 c0 mov %eax,%eax 155: 49 0f a3 04 24 bt %rax,(%r12) After patch (execution in loop): 150: 0f ae e8 lfence 153: 4d 0f a3 34 24 bt %r14,(%r12) ARM64: Before patch (execution in loop): 168: d5033d9f dsb ld 16c: b9405661 ldr w1,[x19,whatawurst#84] 170: 1100fc20 add w0,w1,#0x3f 174: 6b1f003f cmp w1,wzr 178: 1a81b000 csel w0,w0,w1,lt 17c: 130c7000 asr w0,w0,whatawurst#6 180: 937d7c00 sbfiz x0,x0,whatawurst#3,whatawurst#32 184: f8606aa0 ldr x0,[x21,x0] 188: 9ac12401 lsr x1,x0,x1 18c: 36000e61 tbz w1,#0,358 After patch (execution in loop): 1a8: d50339df dsb ld 1ac: f8776ac0 ldr x0,[x22,x23] ab0: ea18001f tst x0,x24 1b4: 54000ea0 b.eq 388 Further observance on ARM64 for 4 seconds shows that cpu_idle_loop is called 8672 times. Shifting the code will save instructions executed in loop and eventually time as well. Signed-off-by: Gaurav Jindal <gaurav.jindal@spreadtrum.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Sanjeev Yadav <sanjeev.yadav@spreadtrum.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160512101330.GA488@gauravjindalubtnb.del.spreadtrum.com Signed-off-by: Ingo Molnar <mingo@kernel.org>

Move the loop-invariant calculation of 'cpu' in do_idle() out of the loop body, because the current CPU is always constant. This improves the generated code both on x86-64 and ARM64: x86-64: Before patch (execution in loop): 864: 0f ae e8 lfence 867: 65 8b 05 c2 38 f1 7e mov %gs:0x7ef138c2(%rip),%eax 86e: 89 c0 mov %eax,%eax 870: 48 0f a3 05 68 19 08 bt %rax,0x1081968(%rip) 877: 01 After patch (execution in loop): 872: 0f ae e8 lfence 875: 4c 0f a3 25 63 19 08 bt %r12,0x1081963(%rip) 87c: 01 ARM64: Before patch (execution in loop): c58: d5033d9f dsb ld c5c: d538d080 mrs x0, tpidr_el1 c60: b8606a61 ldr w1, [x19,x0] c64: 1100fc20 add w0, w1, #0x3f c68: 7100003f cmp w1, #0x0 c6c: 1a81b000 csel w0, w0, w1, lt c70: 13067c00 asr w0, w0, whatawurst#6 c74: 93407c00 sxtw x0, w0 c78: f8607a80 ldr x0, [x20,x0,lsl whatawurst#3] c7c: 9ac12401 lsr x1, x0, x1 c80: 36000581 tbz w1, #0, d30 <do_idle+0x128> After patch (execution in loop): c84: d5033d9f dsb ld c88: f9400260 ldr x0, [x19] c8c: ea14001f tst x0, x20 c90: 54000580 b.eq d40 <do_idle+0x138> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> [ Rewrote the title and the changelog. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: huawei.libin@huawei.com Cc: xiexiuqi@huawei.com Link: http://lkml.kernel.org/r/1508930907-107755-1-git-send-email-cj.chengjian@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>

ARM64 doesn't implement find_first_{zero}_bit in arch code and doesn't enable it in a config. It leads to using find_next_bit() which is less efficient: 0000000000000000 <find_first_bit>: 0: aa0003e4 mov x4, x0 4: aa0103e0 mov x0, x1 8: b4000181 cbz x1, 38 <find_first_bit+0x38> c: f9400083 ldr x3, [x4] 10: d2800802 mov x2, #0x40 // whatawurst#64 14: 91002084 add x4, x4, #0x8 18: b40000c3 cbz x3, 30 <find_first_bit+0x30> 1c: 14000008 b 3c <find_first_bit+0x3c> 20: f8408483 ldr x3, [x4], whatawurst#8 24: 91010045 add x5, x2, #0x40 28: b50000c3 cbnz x3, 40 <find_first_bit+0x40> 2c: aa0503e2 mov x2, x5 30: eb02001f cmp x0, x2 34: 54ffff68 b.hi 20 <find_first_bit+0x20> // b.pmore 38: d65f03c0 ret 3c: d2800002 mov x2, #0x0 // #0 40: dac00063 rbit x3, x3 44: dac01063 clz x3, x3 48: 8b020062 add x2, x3, x2 4c: eb02001f cmp x0, x2 50: 9a829000 csel x0, x0, x2, ls // ls = plast 54: d65f03c0 ret ... 0000000000000118 <_find_next_bit.constprop.1>: 118: eb02007f cmp x3, x2 11c: 540002e2 b.cs 178 <_find_next_bit.constprop.1+0x60> // b.hs, b.nlast 120: d346fc66 lsr x6, x3, whatawurst#6 124: f8667805 ldr x5, [x0, x6, lsl whatawurst#3] 128: b4000061 cbz x1, 134 <_find_next_bit.constprop.1+0x1c> 12c: f8667826 ldr x6, [x1, x6, lsl whatawurst#3] 130: 8a0600a5 and x5, x5, x6 134: ca0400a6 eor x6, x5, x4 138: 92800005 mov x5, #0xffffffffffffffff // #-1 13c: 9ac320a5 lsl x5, x5, x3 140: 927ae463 and x3, x3, #0xffffffffffffffc0 144: ea0600a5 ands x5, x5, x6 148: 54000120 b.eq 16c <_find_next_bit.constprop.1+0x54> // b.none 14c: 1400000e b 184 <_find_next_bit.constprop.1+0x6c> 150: d346fc66 lsr x6, x3, whatawurst#6 154: f8667805 ldr x5, [x0, x6, lsl whatawurst#3] 158: b4000061 cbz x1, 164 <_find_next_bit.constprop.1+0x4c> 15c: f8667826 ldr x6, [x1, x6, lsl whatawurst#3] 160: 8a0600a5 and x5, x5, x6 164: eb05009f cmp x4, x5 168: 540000c1 b.ne 180 <_find_next_bit.constprop.1+0x68> // b.any 16c: 91010063 add x3, x3, #0x40 170: eb03005f cmp x2, x3 174: 54fffee8 b.hi 150 <_find_next_bit.constprop.1+0x38> // b.pmore 178: aa0203e0 mov x0, x2 17c: d65f03c0 ret 180: ca050085 eor x5, x4, x5 184: dac000a5 rbit x5, x5 188: dac010a5 clz x5, x5 18c: 8b0300a3 add x3, x5, x3 190: eb03005f cmp x2, x3 194: 9a839042 csel x2, x2, x3, ls // ls = plast 198: aa0203e0 mov x0, x2 19c: d65f03c0 ret ... 0000000000000238 <find_next_bit>: 238: a9bf7bfd stp x29, x30, [sp, #-16]! 23c: aa0203e3 mov x3, x2 240: d2800004 mov x4, #0x0 // #0 244: aa0103e2 mov x2, x1 248: 910003fd mov x29, sp 24c: d2800001 mov x1, #0x0 // #0 250: 97ffffb2 bl 118 <_find_next_bit.constprop.1> 254: a8c17bfd ldp x29, x30, [sp], whatawurst#16 258: d65f03c0 ret Enabling find_{first,next}_bit() would also benefit for_each_{set,clear}_bit(). On A-53 find_first_bit() is almost twice faster than find_next_bit(), according to lib/find_bit_benchmark (thanks to Alexey for testing): GENERIC_FIND_FIRST_BIT=n: [7126084.948181] find_first_bit: 47389224 ns, 16357 iterations [7126085.032315] find_first_bit: 19048193 ns, 655 iterations GENERIC_FIND_FIRST_BIT=y: [ 84.158068] find_first_bit: 27193319 ns, 16406 iterations [ 84.233005] find_first_bit: 11082437 ns, 656 iterations GENERIC_FIND_FIRST_BIT=n bloats the kernel despite that it disables generation of find_{first,next}_bit(): yury:linux$ scripts/bloat-o-meter vmlinux vmlinux.ffb add/remove: 4/1 grow/shrink: 19/251 up/down: 564/-1692 (-1128) ... Overall, GENERIC_FIND_FIRST_BIT=n is harmful both in terms of performance and code size, and it's better to have GENERIC_FIND_FIRST_BIT enabled. Tested-by: Alexey Klimov <aklimov@redhat.com> Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210225135700.1381396-2-yury.norov@gmail.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

[ Upstream commit d8b5411 ] Shubham was recently asking on netdev why in arm64 JIT we don't multiply the index for accessing the tail call map by 8. That led me into testing out arm64 JIT wrt tail calls and it turned out I got a NULL pointer dereference on the tail call. The buggy access is at: prog = array->ptrs[index]; if (prog == NULL) goto out; [...] 00000060: d2800e0a mov x10, #0x70 // #112 00000064: f86a682a ldr x10, [x1,x10] 00000068: f862694b ldr x11, [x10,x2] 0000006c: b40000ab cbz x11, 0x00000080 [...] The code triggering the crash is f862694b. x1 at the time contains the address of the bpf array, x10 offsetof(struct bpf_array, ptrs). Meaning, above we load the pointer to the program at map slot 0 into x10. x10 can then be NULL if the slot is not occupied, which we later on try to access with a user given offset in x2 that is the map index. Fix this by emitting the following instead: [...] 00000060: d2800e0a mov x10, #0x70 // #112 00000064: 8b0a002a add x10, x1, x10 00000068: d37df04b lsl x11, x2, whatawurst#3 0000006c: f86b694b ldr x11, [x10,x11] 00000070: b40000ab cbz x11, 0x00000084 [...] This basically adds the offset to ptrs to the base address of the bpf array we got and we later on access the map with an index * 8 offset relative to that. The tail call map itself is basically one large area with meta data at the head followed by the array of prog pointers. This makes tail calls working again, tested on Cavium ThunderX ARMv8. Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") Reported-by: Shubham Bansal <illusionist.neo@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ upstream commit 16338a9 ] I recently noticed a crash on arm64 when feeding a bogus index into BPF tail call helper. The crash would not occur when the interpreter is used, but only in case of JIT. Output looks as follows: [ 347.007486] Unable to handle kernel paging request at virtual address fffb850e96492510 [...] [ 347.043065] [fffb850e96492510] address between user and kernel address ranges [ 347.050205] Internal error: Oops: 96000004 [whatawurst#1] SMP [...] [ 347.190829] x13: 0000000000000000 x12: 0000000000000000 [ 347.196128] x11: fffc047ebe782800 x10: ffff808fd7d0fd10 [ 347.201427] x9 : 0000000000000000 x8 : 0000000000000000 [ 347.206726] x7 : 0000000000000000 x6 : 001c991738000000 [ 347.212025] x5 : 0000000000000018 x4 : 000000000000ba5a [ 347.217325] x3 : 00000000000329c4 x2 : ffff808fd7cf0500 [ 347.222625] x1 : ffff808fd7d0fc00 x0 : ffff808fd7cf0500 [ 347.227926] Process test_verifier (pid: 4548, stack limit = 0x000000007467fa61) [ 347.235221] Call trace: [ 347.237656] 0xffff000002f3a4fc [ 347.240784] bpf_test_run+0x78/0xf8 [ 347.244260] bpf_prog_test_run_skb+0x148/0x230 [ 347.248694] SyS_bpf+0x77c/0x1110 [ 347.251999] el0_svc_naked+0x30/0x34 [ 347.255564] Code: 9100075a d280220a 8b0a002a d37df04b (f86b694b) [...] In this case the index used in BPF r3 is the same as in r1 at the time of the call, meaning we fed a pointer as index; here, it had the value 0xffff808fd7cf0500 which sits in x2. While I found tail calls to be working in general (also for hitting the error cases), I noticed the following in the code emission: # bpftool p d j i 988 [...] 38: ldr w10, [x1,x10] 3c: cmp w2, w10 40: b.ge 0x000000000000007c <-- signed cmp 44: mov x10, #0x20 // whatawurst#32 48: cmp x26, x10 4c: b.gt 0x000000000000007c 50: add x26, x26, #0x1 54: mov x10, #0x110 // #272 58: add x10, x1, x10 5c: lsl x11, x2, whatawurst#3 60: ldr x11, [x10,x11] <-- faulting insn (f86b694b) 64: cbz x11, 0x000000000000007c [...] Meaning, the tests passed because commit ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") was using signed compares instead of unsigned which as a result had the test wrongly passing. Change this but also the tail call count test both into unsigned and cap the index as u32. Latter we did as well in 90caccd ("bpf: fix bpf_tail_call() x64 JIT") and is needed in addition here, too. Tested on HiSilicon Hi1616. Result after patch: # bpftool p d j i 268 [...] 38: ldr w10, [x1,x10] 3c: add w2, w2, #0x0 40: cmp w2, w10 44: b.cs 0x0000000000000080 48: mov x10, #0x20 // whatawurst#32 4c: cmp x26, x10 50: b.hi 0x0000000000000080 54: add x26, x26, #0x1 58: mov x10, #0x110 // #272 5c: add x10, x1, x10 60: lsl x11, x2, whatawurst#3 64: ldr x11, [x10,x11] 68: cbz x11, 0x0000000000000080 [...] Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit d8b5411 ] Shubham was recently asking on netdev why in arm64 JIT we don't multiply the index for accessing the tail call map by 8. That led me into testing out arm64 JIT wrt tail calls and it turned out I got a NULL pointer dereference on the tail call. The buggy access is at: prog = array->ptrs[index]; if (prog == NULL) goto out; [...] 00000060: d2800e0a mov x10, #0x70 // #112 00000064: f86a682a ldr x10, [x1,x10] 00000068: f862694b ldr x11, [x10,x2] 0000006c: b40000ab cbz x11, 0x00000080 [...] The code triggering the crash is f862694b. x1 at the time contains the address of the bpf array, x10 offsetof(struct bpf_array, ptrs). Meaning, above we load the pointer to the program at map slot 0 into x10. x10 can then be NULL if the slot is not occupied, which we later on try to access with a user given offset in x2 that is the map index. Fix this by emitting the following instead: [...] 00000060: d2800e0a mov x10, #0x70 // #112 00000064: 8b0a002a add x10, x1, x10 00000068: d37df04b lsl x11, x2, whatawurst#3 0000006c: f86b694b ldr x11, [x10,x11] 00000070: b40000ab cbz x11, 0x00000084 [...] This basically adds the offset to ptrs to the base address of the bpf array we got and we later on access the map with an index * 8 offset relative to that. The tail call map itself is basically one large area with meta data at the head followed by the array of prog pointers. This makes tail calls working again, tested on Cavium ThunderX ARMv8. Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") Reported-by: Shubham Bansal <illusionist.neo@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ upstream commit 16338a9 ] I recently noticed a crash on arm64 when feeding a bogus index into BPF tail call helper. The crash would not occur when the interpreter is used, but only in case of JIT. Output looks as follows: [ 347.007486] Unable to handle kernel paging request at virtual address fffb850e96492510 [...] [ 347.043065] [fffb850e96492510] address between user and kernel address ranges [ 347.050205] Internal error: Oops: 96000004 [whatawurst#1] SMP [...] [ 347.190829] x13: 0000000000000000 x12: 0000000000000000 [ 347.196128] x11: fffc047ebe782800 x10: ffff808fd7d0fd10 [ 347.201427] x9 : 0000000000000000 x8 : 0000000000000000 [ 347.206726] x7 : 0000000000000000 x6 : 001c991738000000 [ 347.212025] x5 : 0000000000000018 x4 : 000000000000ba5a [ 347.217325] x3 : 00000000000329c4 x2 : ffff808fd7cf0500 [ 347.222625] x1 : ffff808fd7d0fc00 x0 : ffff808fd7cf0500 [ 347.227926] Process test_verifier (pid: 4548, stack limit = 0x000000007467fa61) [ 347.235221] Call trace: [ 347.237656] 0xffff000002f3a4fc [ 347.240784] bpf_test_run+0x78/0xf8 [ 347.244260] bpf_prog_test_run_skb+0x148/0x230 [ 347.248694] SyS_bpf+0x77c/0x1110 [ 347.251999] el0_svc_naked+0x30/0x34 [ 347.255564] Code: 9100075a d280220a 8b0a002a d37df04b (f86b694b) [...] In this case the index used in BPF r3 is the same as in r1 at the time of the call, meaning we fed a pointer as index; here, it had the value 0xffff808fd7cf0500 which sits in x2. While I found tail calls to be working in general (also for hitting the error cases), I noticed the following in the code emission: # bpftool p d j i 988 [...] 38: ldr w10, [x1,x10] 3c: cmp w2, w10 40: b.ge 0x000000000000007c <-- signed cmp 44: mov x10, #0x20 // whatawurst#32 48: cmp x26, x10 4c: b.gt 0x000000000000007c 50: add x26, x26, #0x1 54: mov x10, #0x110 // #272 58: add x10, x1, x10 5c: lsl x11, x2, whatawurst#3 60: ldr x11, [x10,x11] <-- faulting insn (f86b694b) 64: cbz x11, 0x000000000000007c [...] Meaning, the tests passed because commit ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") was using signed compares instead of unsigned which as a result had the test wrongly passing. Change this but also the tail call count test both into unsigned and cap the index as u32. Latter we did as well in 90caccd ("bpf: fix bpf_tail_call() x64 JIT") and is needed in addition here, too. Tested on HiSilicon Hi1616. Result after patch: # bpftool p d j i 268 [...] 38: ldr w10, [x1,x10] 3c: add w2, w2, #0x0 40: cmp w2, w10 44: b.cs 0x0000000000000080 48: mov x10, #0x20 // whatawurst#32 4c: cmp x26, x10 50: b.hi 0x0000000000000080 54: add x26, x26, #0x1 58: mov x10, #0x110 // #272 5c: add x10, x1, x10 60: lsl x11, x2, whatawurst#3 64: ldr x11, [x10,x11] 68: cbz x11, 0x0000000000000080 [...] Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit d8b5411 ] Shubham was recently asking on netdev why in arm64 JIT we don't multiply the index for accessing the tail call map by 8. That led me into testing out arm64 JIT wrt tail calls and it turned out I got a NULL pointer dereference on the tail call. The buggy access is at: prog = array->ptrs[index]; if (prog == NULL) goto out; [...] 00000060: d2800e0a mov x10, #0x70 // #112 00000064: f86a682a ldr x10, [x1,x10] 00000068: f862694b ldr x11, [x10,x2] 0000006c: b40000ab cbz x11, 0x00000080 [...] The code triggering the crash is f862694b. x1 at the time contains the address of the bpf array, x10 offsetof(struct bpf_array, ptrs). Meaning, above we load the pointer to the program at map slot 0 into x10. x10 can then be NULL if the slot is not occupied, which we later on try to access with a user given offset in x2 that is the map index. Fix this by emitting the following instead: [...] 00000060: d2800e0a mov x10, #0x70 // #112 00000064: 8b0a002a add x10, x1, x10 00000068: d37df04b lsl x11, x2, whatawurst#3 0000006c: f86b694b ldr x11, [x10,x11] 00000070: b40000ab cbz x11, 0x00000084 [...] This basically adds the offset to ptrs to the base address of the bpf array we got and we later on access the map with an index * 8 offset relative to that. The tail call map itself is basically one large area with meta data at the head followed by the array of prog pointers. This makes tail calls working again, tested on Cavium ThunderX ARMv8. Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") Reported-by: Shubham Bansal <illusionist.neo@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ upstream commit 16338a9 ] I recently noticed a crash on arm64 when feeding a bogus index into BPF tail call helper. The crash would not occur when the interpreter is used, but only in case of JIT. Output looks as follows: [ 347.007486] Unable to handle kernel paging request at virtual address fffb850e96492510 [...] [ 347.043065] [fffb850e96492510] address between user and kernel address ranges [ 347.050205] Internal error: Oops: 96000004 [whatawurst#1] SMP [...] [ 347.190829] x13: 0000000000000000 x12: 0000000000000000 [ 347.196128] x11: fffc047ebe782800 x10: ffff808fd7d0fd10 [ 347.201427] x9 : 0000000000000000 x8 : 0000000000000000 [ 347.206726] x7 : 0000000000000000 x6 : 001c991738000000 [ 347.212025] x5 : 0000000000000018 x4 : 000000000000ba5a [ 347.217325] x3 : 00000000000329c4 x2 : ffff808fd7cf0500 [ 347.222625] x1 : ffff808fd7d0fc00 x0 : ffff808fd7cf0500 [ 347.227926] Process test_verifier (pid: 4548, stack limit = 0x000000007467fa61) [ 347.235221] Call trace: [ 347.237656] 0xffff000002f3a4fc [ 347.240784] bpf_test_run+0x78/0xf8 [ 347.244260] bpf_prog_test_run_skb+0x148/0x230 [ 347.248694] SyS_bpf+0x77c/0x1110 [ 347.251999] el0_svc_naked+0x30/0x34 [ 347.255564] Code: 9100075a d280220a 8b0a002a d37df04b (f86b694b) [...] In this case the index used in BPF r3 is the same as in r1 at the time of the call, meaning we fed a pointer as index; here, it had the value 0xffff808fd7cf0500 which sits in x2. While I found tail calls to be working in general (also for hitting the error cases), I noticed the following in the code emission: # bpftool p d j i 988 [...] 38: ldr w10, [x1,x10] 3c: cmp w2, w10 40: b.ge 0x000000000000007c <-- signed cmp 44: mov x10, #0x20 // whatawurst#32 48: cmp x26, x10 4c: b.gt 0x000000000000007c 50: add x26, x26, #0x1 54: mov x10, #0x110 // #272 58: add x10, x1, x10 5c: lsl x11, x2, whatawurst#3 60: ldr x11, [x10,x11] <-- faulting insn (f86b694b) 64: cbz x11, 0x000000000000007c [...] Meaning, the tests passed because commit ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") was using signed compares instead of unsigned which as a result had the test wrongly passing. Change this but also the tail call count test both into unsigned and cap the index as u32. Latter we did as well in 90caccd ("bpf: fix bpf_tail_call() x64 JIT") and is needed in addition here, too. Tested on HiSilicon Hi1616. Result after patch: # bpftool p d j i 268 [...] 38: ldr w10, [x1,x10] 3c: add w2, w2, #0x0 40: cmp w2, w10 44: b.cs 0x0000000000000080 48: mov x10, #0x20 // whatawurst#32 4c: cmp x26, x10 50: b.hi 0x0000000000000080 54: add x26, x26, #0x1 58: mov x10, #0x110 // #272 5c: add x10, x1, x10 60: lsl x11, x2, whatawurst#3 64: ldr x11, [x10,x11] 68: cbz x11, 0x0000000000000080 [...] Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Move the loop-invariant calculation of 'cpu' in do_idle() out of the loop body, because the current CPU is always constant. This improves the generated code both on x86-64 and ARM64: x86-64: Before patch (execution in loop): 864: 0f ae e8 lfence 867: 65 8b 05 c2 38 f1 7e mov %gs:0x7ef138c2(%rip),%eax 86e: 89 c0 mov %eax,%eax 870: 48 0f a3 05 68 19 08 bt %rax,0x1081968(%rip) 877: 01 After patch (execution in loop): 872: 0f ae e8 lfence 875: 4c 0f a3 25 63 19 08 bt %r12,0x1081963(%rip) 87c: 01 ARM64: Before patch (execution in loop): c58: d5033d9f dsb ld c5c: d538d080 mrs x0, tpidr_el1 c60: b8606a61 ldr w1, [x19,x0] c64: 1100fc20 add w0, w1, #0x3f c68: 7100003f cmp w1, #0x0 c6c: 1a81b000 csel w0, w0, w1, lt c70: 13067c00 asr w0, w0, whatawurst#6 c74: 93407c00 sxtw x0, w0 c78: f8607a80 ldr x0, [x20,x0,lsl whatawurst#3] c7c: 9ac12401 lsr x1, x0, x1 c80: 36000581 tbz w1, #0, d30 <do_idle+0x128> After patch (execution in loop): c84: d5033d9f dsb ld c88: f9400260 ldr x0, [x19] c8c: ea14001f tst x0, x20 c90: 54000580 b.eq d40 <do_idle+0x138> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> [ Rewrote the title and the changelog. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: huawei.libin@huawei.com Cc: xiexiuqi@huawei.com Link: http://lkml.kernel.org/r/1508930907-107755-1-git-send-email-cj.chengjian@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>

[ Upstream commit af68656d66eda219b7f55ce8313a1da0312c79e1 ] While handling PCI errors (AER flow) driver tries to disable NAPI [napi_disable()] after NAPI is deleted [__netif_napi_del()] which causes unexpected system hang/crash. System message log shows the following: ======================================= [ 3222.537510] EEH: Detected PCI bus error on PHB#384-PE#800000 [ 3222.537511] EEH: This PCI device has failed 2 times in the last hour and will be permanently disabled after 5 failures. [ 3222.537512] EEH: Notify device drivers to shutdown [ 3222.537513] EEH: Beginning: 'error_detected(IO frozen)' [ 3222.537514] EEH: PE#800000 (PCI 0384:80:00.0): Invoking bnx2x->error_detected(IO frozen) [ 3222.537516] bnx2x: [bnx2x_io_error_detected:14236(eth14)]IO error detected [ 3222.537650] EEH: PE#800000 (PCI 0384:80:00.0): bnx2x driver reports: 'need reset' [ 3222.537651] EEH: PE#800000 (PCI 0384:80:00.1): Invoking bnx2x->error_detected(IO frozen) [ 3222.537651] bnx2x: [bnx2x_io_error_detected:14236(eth13)]IO error detected [ 3222.537729] EEH: PE#800000 (PCI 0384:80:00.1): bnx2x driver reports: 'need reset' [ 3222.537729] EEH: Finished:'error_detected(IO frozen)' with aggregate recovery state:'need reset' [ 3222.537890] EEH: Collect temporary log [ 3222.583481] EEH: of node=0384:80:00.0 [ 3222.583519] EEH: PCI device/vendor: 168e14e4 [ 3222.583557] EEH: PCI cmd/status register: 00100140 [ 3222.583557] EEH: PCI-E capabilities and status follow: [ 3222.583744] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.583892] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.583893] EEH: PCI-E 20: 00000000 [ 3222.583893] EEH: PCI-E AER capability register set follows: [ 3222.584079] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.584230] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.584378] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.584416] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.584416] EEH: of node=0384:80:00.1 [ 3222.584454] EEH: PCI device/vendor: 168e14e4 [ 3222.584491] EEH: PCI cmd/status register: 00100140 [ 3222.584492] EEH: PCI-E capabilities and status follow: [ 3222.584677] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.584825] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.584826] EEH: PCI-E 20: 00000000 [ 3222.584826] EEH: PCI-E AER capability register set follows: [ 3222.585011] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.585160] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.585309] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.585347] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.586872] RTAS: event: 5, Type: Platform Error (224), Severity: 2 [ 3222.586873] EEH: Reset without hotplug activity [ 3224.762767] EEH: Beginning: 'slot_reset' [ 3224.762770] EEH: PE#800000 (PCI 0384:80:00.0): Invoking bnx2x->slot_reset() [ 3224.762771] bnx2x: [bnx2x_io_slot_reset:14271(eth14)]IO slot reset initializing... [ 3224.762887] bnx2x 0384:80:00.0: enabling device (0140 -> 0142) [ 3224.768157] bnx2x: [bnx2x_io_slot_reset:14287(eth14)]IO slot reset --> driver unload Uninterruptible tasks ===================== crash> ps | grep UN 213 2 11 c000000004c89e00 UN 0.0 0 0 [eehd] 215 2 0 c000000004c80000 UN 0.0 0 0 [kworker/0:2] 2196 1 28 c000000004504f00 UN 0.1 15936 11136 wickedd 4287 1 9 c00000020d076800 UN 0.0 4032 3008 agetty 4289 1 20 c00000020d056680 UN 0.0 7232 3840 agetty 32423 2 26 c00000020038c580 UN 0.0 0 0 [kworker/26:3] 32871 4241 27 c0000002609ddd00 UN 0.1 18624 11648 sshd 32920 10130 16 c00000027284a100 UN 0.1 48512 12608 sendmail 33092 32987 0 c000000205218b00 UN 0.1 48512 12608 sendmail 33154 4567 16 c000000260e51780 UN 0.1 48832 12864 pickup 33209 4241 36 c000000270cb6500 UN 0.1 18624 11712 sshd 33473 33283 0 c000000205211480 UN 0.1 48512 12672 sendmail 33531 4241 37 c00000023c902780 UN 0.1 18624 11648 sshd EEH handler hung while bnx2x sleeping and holding RTNL lock =========================================================== crash> bt 213 PID: 213 TASK: c000000004c89e00 CPU: 11 COMMAND: "eehd" #0 [c000000004d477e0] __schedule at c000000000c70808 whatawurst#1 [c000000004d478b0] schedule at c000000000c70ee0 whatawurst#2 [c000000004d478e0] schedule_timeout at c000000000c76dec whatawurst#3 [c000000004d479c0] msleep at c0000000002120cc whatawurst#4 [c000000004d479f0] napi_disable at c000000000a06448 ^^^^^^^^^^^^^^^^ whatawurst#5 [c000000004d47a30] bnx2x_netif_stop at c0080000018dba94 [bnx2x] whatawurst#6 [c000000004d47a60] bnx2x_io_slot_reset at c0080000018a551c [bnx2x] whatawurst#7 [c000000004d47b20] eeh_report_reset at c00000000004c9bc whatawurst#8 [c000000004d47b90] eeh_pe_report at c00000000004d1a8 whatawurst#9 [c000000004d47c40] eeh_handle_normal_event at c00000000004da64 And the sleeping source code ============================ crash> dis -ls c000000000a06448 FILE: ../net/core/dev.c LINE: 6702 6697 { 6698 might_sleep(); 6699 set_bit(NAPI_STATE_DISABLE, &n->state); 6700 6701 while (test_and_set_bit(NAPI_STATE_SCHED, &n->state)) * 6702 msleep(1); 6703 while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state)) 6704 msleep(1); 6705 6706 hrtimer_cancel(&n->timer); 6707 6708 clear_bit(NAPI_STATE_DISABLE, &n->state); 6709 } EEH calls into bnx2x twice based on the system log above, first through bnx2x_io_error_detected() and then bnx2x_io_slot_reset(), and executes the following call chains: bnx2x_io_error_detected() +-> bnx2x_eeh_nic_unload() +-> bnx2x_del_all_napi() +-> __netif_napi_del() bnx2x_io_slot_reset() +-> bnx2x_netif_stop() +-> bnx2x_napi_disable() +->napi_disable() Fix this by correcting the sequence of NAPI APIs usage, that is delete the NAPI after disabling it. Fixes: 7fa6f34 ("bnx2x: AER revised") Reported-by: David Christensen <drc@linux.vnet.ibm.com> Tested-by: David Christensen <drc@linux.vnet.ibm.com> Signed-off-by: Manish Chopra <manishc@marvell.com> Signed-off-by: Ariel Elior <aelior@marvell.com> Link: https://lore.kernel.org/r/20220426153913.6966-1-manishc@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

Move the loop-invariant calculation of 'cpu' in do_idle() out of the loop body, because the current CPU is always constant. This improves the generated code both on x86-64 and ARM64: x86-64: Before patch (execution in loop): 864: 0f ae e8 lfence 867: 65 8b 05 c2 38 f1 7e mov %gs:0x7ef138c2(%rip),%eax 86e: 89 c0 mov %eax,%eax 870: 48 0f a3 05 68 19 08 bt %rax,0x1081968(%rip) 877: 01 After patch (execution in loop): 872: 0f ae e8 lfence 875: 4c 0f a3 25 63 19 08 bt %r12,0x1081963(%rip) 87c: 01 ARM64: Before patch (execution in loop): c58: d5033d9f dsb ld c5c: d538d080 mrs x0, tpidr_el1 c60: b8606a61 ldr w1, [x19,x0] c64: 1100fc20 add w0, w1, #0x3f c68: 7100003f cmp w1, #0x0 c6c: 1a81b000 csel w0, w0, w1, lt c70: 13067c00 asr w0, w0, whatawurst#6 c74: 93407c00 sxtw x0, w0 c78: f8607a80 ldr x0, [x20,x0,lsl whatawurst#3] c7c: 9ac12401 lsr x1, x0, x1 c80: 36000581 tbz w1, #0, d30 <do_idle+0x128> After patch (execution in loop): c84: d5033d9f dsb ld c88: f9400260 ldr x0, [x19] c8c: ea14001f tst x0, x20 c90: 54000580 b.eq d40 <do_idle+0x138> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> [ Rewrote the title and the changelog. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: huawei.libin@huawei.com Cc: xiexiuqi@huawei.com Link: http://lkml.kernel.org/r/1508930907-107755-1-git-send-email-cj.chengjian@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>

commit 9c6d778800b921bde3bff3cff5003d1650f942d1 upstream. Automatic kernel fuzzing revealed a recursive locking violation in usb-storage: ============================================ WARNING: possible recursive locking detected 5.18.0 whatawurst#3 Not tainted -------------------------------------------- kworker/1:3/1205 is trying to acquire lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 but task is already holding lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 ... stack backtrace: CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 whatawurst#3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2988 [inline] check_deadlock kernel/locking/lockdep.c:3031 [inline] validate_chain kernel/locking/lockdep.c:3816 [inline] __lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747 usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109 r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622 usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:545 [inline] device_remove+0x11f/0x170 drivers/base/dd.c:537 __device_release_driver drivers/base/dd.c:1222 [inline] device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248 usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627 usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118 usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114 This turned out not to be an error in usb-storage but rather a nested device reset attempt. That is, as the rtl8712 driver was being unbound from a composite device in preparation for an unrelated USB reset (that driver does not have pre_reset or post_reset callbacks), its ->remove routine called usb_reset_device() -- thus nesting one reset call within another. Performing a reset as part of disconnect processing is a questionable practice at best. However, the bug report points out that the USB core does not have any protection against nested resets. Adding a reset_in_progress flag and testing it will prevent such errors in the future. Link: https://lore.kernel.org/all/CAB7eexKUpvX-JNiLzhXBDWgfg2T9e9_0Tw4HQ6keN==voRbP0g@mail.gmail.com/ Cc: stable@vger.kernel.org Reported-and-tested-by: Rondreis <linhaoguo86@gmail.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Link: https://lore.kernel.org/r/YwkflDxvg0KWqyZK@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit af68656d66eda219b7f55ce8313a1da0312c79e1 ] While handling PCI errors (AER flow) driver tries to disable NAPI [napi_disable()] after NAPI is deleted [__netif_napi_del()] which causes unexpected system hang/crash. System message log shows the following: ======================================= [ 3222.537510] EEH: Detected PCI bus error on PHB#384-PE#800000 [ 3222.537511] EEH: This PCI device has failed 2 times in the last hour and will be permanently disabled after 5 failures. [ 3222.537512] EEH: Notify device drivers to shutdown [ 3222.537513] EEH: Beginning: 'error_detected(IO frozen)' [ 3222.537514] EEH: PE#800000 (PCI 0384:80:00.0): Invoking bnx2x->error_detected(IO frozen) [ 3222.537516] bnx2x: [bnx2x_io_error_detected:14236(eth14)]IO error detected [ 3222.537650] EEH: PE#800000 (PCI 0384:80:00.0): bnx2x driver reports: 'need reset' [ 3222.537651] EEH: PE#800000 (PCI 0384:80:00.1): Invoking bnx2x->error_detected(IO frozen) [ 3222.537651] bnx2x: [bnx2x_io_error_detected:14236(eth13)]IO error detected [ 3222.537729] EEH: PE#800000 (PCI 0384:80:00.1): bnx2x driver reports: 'need reset' [ 3222.537729] EEH: Finished:'error_detected(IO frozen)' with aggregate recovery state:'need reset' [ 3222.537890] EEH: Collect temporary log [ 3222.583481] EEH: of node=0384:80:00.0 [ 3222.583519] EEH: PCI device/vendor: 168e14e4 [ 3222.583557] EEH: PCI cmd/status register: 00100140 [ 3222.583557] EEH: PCI-E capabilities and status follow: [ 3222.583744] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.583892] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.583893] EEH: PCI-E 20: 00000000 [ 3222.583893] EEH: PCI-E AER capability register set follows: [ 3222.584079] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.584230] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.584378] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.584416] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.584416] EEH: of node=0384:80:00.1 [ 3222.584454] EEH: PCI device/vendor: 168e14e4 [ 3222.584491] EEH: PCI cmd/status register: 00100140 [ 3222.584492] EEH: PCI-E capabilities and status follow: [ 3222.584677] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.584825] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.584826] EEH: PCI-E 20: 00000000 [ 3222.584826] EEH: PCI-E AER capability register set follows: [ 3222.585011] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.585160] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.585309] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.585347] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.586872] RTAS: event: 5, Type: Platform Error (224), Severity: 2 [ 3222.586873] EEH: Reset without hotplug activity [ 3224.762767] EEH: Beginning: 'slot_reset' [ 3224.762770] EEH: PE#800000 (PCI 0384:80:00.0): Invoking bnx2x->slot_reset() [ 3224.762771] bnx2x: [bnx2x_io_slot_reset:14271(eth14)]IO slot reset initializing... [ 3224.762887] bnx2x 0384:80:00.0: enabling device (0140 -> 0142) [ 3224.768157] bnx2x: [bnx2x_io_slot_reset:14287(eth14)]IO slot reset --> driver unload Uninterruptible tasks ===================== crash> ps | grep UN 213 2 11 c000000004c89e00 UN 0.0 0 0 [eehd] 215 2 0 c000000004c80000 UN 0.0 0 0 [kworker/0:2] 2196 1 28 c000000004504f00 UN 0.1 15936 11136 wickedd 4287 1 9 c00000020d076800 UN 0.0 4032 3008 agetty 4289 1 20 c00000020d056680 UN 0.0 7232 3840 agetty 32423 2 26 c00000020038c580 UN 0.0 0 0 [kworker/26:3] 32871 4241 27 c0000002609ddd00 UN 0.1 18624 11648 sshd 32920 10130 16 c00000027284a100 UN 0.1 48512 12608 sendmail 33092 32987 0 c000000205218b00 UN 0.1 48512 12608 sendmail 33154 4567 16 c000000260e51780 UN 0.1 48832 12864 pickup 33209 4241 36 c000000270cb6500 UN 0.1 18624 11712 sshd 33473 33283 0 c000000205211480 UN 0.1 48512 12672 sendmail 33531 4241 37 c00000023c902780 UN 0.1 18624 11648 sshd EEH handler hung while bnx2x sleeping and holding RTNL lock =========================================================== crash> bt 213 PID: 213 TASK: c000000004c89e00 CPU: 11 COMMAND: "eehd" #0 [c000000004d477e0] __schedule at c000000000c70808 whatawurst#1 [c000000004d478b0] schedule at c000000000c70ee0 whatawurst#2 [c000000004d478e0] schedule_timeout at c000000000c76dec whatawurst#3 [c000000004d479c0] msleep at c0000000002120cc whatawurst#4 [c000000004d479f0] napi_disable at c000000000a06448 ^^^^^^^^^^^^^^^^ whatawurst#5 [c000000004d47a30] bnx2x_netif_stop at c0080000018dba94 [bnx2x] whatawurst#6 [c000000004d47a60] bnx2x_io_slot_reset at c0080000018a551c [bnx2x] whatawurst#7 [c000000004d47b20] eeh_report_reset at c00000000004c9bc whatawurst#8 [c000000004d47b90] eeh_pe_report at c00000000004d1a8 whatawurst#9 [c000000004d47c40] eeh_handle_normal_event at c00000000004da64 And the sleeping source code ============================ crash> dis -ls c000000000a06448 FILE: ../net/core/dev.c LINE: 6702 6697 { 6698 might_sleep(); 6699 set_bit(NAPI_STATE_DISABLE, &n->state); 6700 6701 while (test_and_set_bit(NAPI_STATE_SCHED, &n->state)) * 6702 msleep(1); 6703 while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state)) 6704 msleep(1); 6705 6706 hrtimer_cancel(&n->timer); 6707 6708 clear_bit(NAPI_STATE_DISABLE, &n->state); 6709 } EEH calls into bnx2x twice based on the system log above, first through bnx2x_io_error_detected() and then bnx2x_io_slot_reset(), and executes the following call chains: bnx2x_io_error_detected() +-> bnx2x_eeh_nic_unload() +-> bnx2x_del_all_napi() +-> __netif_napi_del() bnx2x_io_slot_reset() +-> bnx2x_netif_stop() +-> bnx2x_napi_disable() +->napi_disable() Fix this by correcting the sequence of NAPI APIs usage, that is delete the NAPI after disabling it. Fixes: 7fa6f34 ("bnx2x: AER revised") Reported-by: David Christensen <drc@linux.vnet.ibm.com> Tested-by: David Christensen <drc@linux.vnet.ibm.com> Signed-off-by: Manish Chopra <manishc@marvell.com> Signed-off-by: Ariel Elior <aelior@marvell.com> Link: https://lore.kernel.org/r/20220426153913.6966-1-manishc@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

commit 9c6d778800b921bde3bff3cff5003d1650f942d1 upstream. Automatic kernel fuzzing revealed a recursive locking violation in usb-storage: ============================================ WARNING: possible recursive locking detected 5.18.0 whatawurst#3 Not tainted -------------------------------------------- kworker/1:3/1205 is trying to acquire lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 but task is already holding lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 ... stack backtrace: CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 whatawurst#3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2988 [inline] check_deadlock kernel/locking/lockdep.c:3031 [inline] validate_chain kernel/locking/lockdep.c:3816 [inline] __lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747 usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109 r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622 usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:545 [inline] device_remove+0x11f/0x170 drivers/base/dd.c:537 __device_release_driver drivers/base/dd.c:1222 [inline] device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248 usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627 usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118 usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114 This turned out not to be an error in usb-storage but rather a nested device reset attempt. That is, as the rtl8712 driver was being unbound from a composite device in preparation for an unrelated USB reset (that driver does not have pre_reset or post_reset callbacks), its ->remove routine called usb_reset_device() -- thus nesting one reset call within another. Performing a reset as part of disconnect processing is a questionable practice at best. However, the bug report points out that the USB core does not have any protection against nested resets. Adding a reset_in_progress flag and testing it will prevent such errors in the future. Link: https://lore.kernel.org/all/CAB7eexKUpvX-JNiLzhXBDWgfg2T9e9_0Tw4HQ6keN==voRbP0g@mail.gmail.com/ Cc: stable@vger.kernel.org Reported-and-tested-by: Rondreis <linhaoguo86@gmail.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Link: https://lore.kernel.org/r/YwkflDxvg0KWqyZK@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

…g the sock [ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ] There is a race condition in vxlan that when deleting a vxlan device during receiving packets, there is a possibility that the sock is released after getting vxlan_sock vs from sk_user_data. Then in later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got NULL pointer dereference. e.g. #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757 whatawurst#1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d whatawurst#2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48 whatawurst#3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b whatawurst#4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb whatawurst#5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542 whatawurst#6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62 [exception RIP: vxlan_ecn_decapsulate+0x3b] RIP: ffffffffc1014e7b RSP: ffffa25ec6978cb0 RFLAGS: 00010246 RAX: 0000000000000008 RBX: ffff8aa000888000 RCX: 0000000000000000 RDX: 000000000000000e RSI: ffff8a9fc7ab803e RDI: ffff8a9fd1168700 RBP: ffff8a9fc7ab803e R8: 0000000000700000 R9: 00000000000010ae R10: ffff8a9fcb748980 R11: 0000000000000000 R12: ffff8a9fd1168700 R13: ffff8aa000888000 R14: 00000000002a0000 R15: 00000000000010ae ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 whatawurst#7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan] whatawurst#8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507 whatawurst#9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45 whatawurst#10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807 whatawurst#11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951 whatawurst#12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde whatawurst#13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b whatawurst#14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139 whatawurst#15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a whatawurst#16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3 whatawurst#17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca whatawurst#18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3 Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh Fix this by waiting for all sk_user_data reader to finish before releasing the sock. Reported-by: Jianlin Shi <jishi@redhat.com> Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Ulrich Hecht <uli+cip@fpond.eu>

@m

commit 11933cf1d91d57da9e5c53822a540bbdc2656c16 upstream. The propagate_mnt() function handles mount propagation when creating mounts and propagates the source mount tree @source_mnt to all applicable nodes of the destination propagation mount tree headed by @dest_mnt. Unfortunately it contains a bug where it fails to terminate at peers of @source_mnt when looking up copies of the source mount that become masters for copies of the source mount tree mounted on top of slaves in the destination propagation tree causing a NULL dereference. Once the mechanics of the bug are understood it's easy to trigger. Because of unprivileged user namespaces it is available to unprivileged users. While fixing this bug we've gotten confused multiple times due to unclear terminology or missing concepts. So let's start this with some clarifications: * The terms "master" or "peer" denote a shared mount. A shared mount belongs to a peer group. * A peer group is a set of shared mounts that propagate to each other. They are identified by a peer group id. The peer group id is available in @shared_mnt->mnt_group_id. Shared mounts within the same peer group have the same peer group id. The peers in a peer group can be reached via @shared_mnt->mnt_share. * The terms "slave mount" or "dependent mount" denote a mount that receives propagation from a peer in a peer group. IOW, shared mounts may have slave mounts and slave mounts have shared mounts as their master. Slave mounts of a given peer in a peer group are listed on that peers slave list available at @shared_mnt->mnt_slave_list. * The term "master mount" denotes a mount in a peer group. IOW, it denotes a shared mount or a peer mount in a peer group. The term "master mount" - or "master" for short - is mostly used when talking in the context of slave mounts that receive propagation from a master mount. A master mount of a slave identifies the closest peer group a slave mount receives propagation from. The master mount of a slave can be identified via @slave_mount->mnt_master. Different slaves may point to different masters in the same peer group. * Multiple peers in a peer group can have non-empty ->mnt_slave_lists. Non-empty ->mnt_slave_lists of peers don't intersect. Consequently, to ensure all slave mounts of a peer group are visited the ->mnt_slave_lists of all peers in a peer group have to be walked. * Slave mounts point to a peer in the closest peer group they receive propagation from via @slave_mnt->mnt_master (see above). Together with these peers they form a propagation group (see below). The closest peer group can thus be identified through the peer group id @slave_mnt->mnt_master->mnt_group_id of the peer/master that a slave mount receives propagation from. * A shared-slave mount is a slave mount to a peer group pg1 while also a peer in another peer group pg2. IOW, a peer group may receive propagation from another peer group. If a peer group pg1 is a slave to another peer group pg2 then all peers in peer group pg1 point to the same peer in peer group pg2 via ->mnt_master. IOW, all peers in peer group pg1 appear on the same ->mnt_slave_list. IOW, they cannot be slaves to different peer groups. * A pure slave mount is a slave mount that is a slave to a peer group but is not a peer in another peer group. * A propagation group denotes the set of mounts consisting of a single peer group pg1 and all slave mounts and shared-slave mounts that point to a peer in that peer group via ->mnt_master. IOW, all slave mounts such that @slave_mnt->mnt_master->mnt_group_id is equal to @shared_mnt->mnt_group_id. The concept of a propagation group makes it easier to talk about a single propagation level in a propagation tree. For example, in propagate_mnt() the immediate peers of @dest_mnt and all slaves of @dest_mnt's peer group form a propagation group propg1. So a shared-slave mount that is a slave in propg1 and that is a peer in another peer group pg2 forms another propagation group propg2 together with all slaves that point to that shared-slave mount in their ->mnt_master. * A propagation tree refers to all mounts that receive propagation starting from a specific shared mount. For example, for propagate_mnt() @dest_mnt is the start of a propagation tree. The propagation tree ecompasses all mounts that receive propagation from @dest_mnt's peer group down to the leafs. With that out of the way let's get to the actual algorithm. We know that @dest_mnt is guaranteed to be a pure shared mount or a shared-slave mount. This is guaranteed by a check in attach_recursive_mnt(). So propagate_mnt() will first propagate the source mount tree to all peers in @dest_mnt's peer group: for (n = next_peer(dest_mnt); n != dest_mnt; n = next_peer(n)) { ret = propagate_one(n); if (ret) goto out; } Notice, that the peer propagation loop of propagate_mnt() doesn't propagate @dest_mnt itself. @dest_mnt is mounted directly in attach_recursive_mnt() after we propagated to the destination propagation tree. The mount that will be mounted on top of @dest_mnt is @source_mnt. This copy was created earlier even before we entered attach_recursive_mnt() and doesn't concern us a lot here. It's just important to notice that when propagate_mnt() is called @source_mnt will not yet have been mounted on top of @dest_mnt. Thus, @source_mnt->mnt_parent will either still point to @source_mnt or - in the case @source_mnt is moved and thus already attached - still to its former parent. For each peer @m in @dest_mnt's peer group propagate_one() will create a new copy of the source mount tree and mount that copy @child on @m such that @child->mnt_parent points to @m after propagate_one() returns. propagate_one() will stash the last destination propagation node @m in @last_dest and the last copy it created for the source mount tree in @last_source. Hence, if we call into propagate_one() again for the next destination propagation node @m, @last_dest will point to the previous destination propagation node and @last_source will point to the previous copy of the source mount tree and mounted on @last_dest. Each new copy of the source mount tree is created from the previous copy of the source mount tree. This will become important later. The peer loop in propagate_mnt() is straightforward. We iterate through the peers copying and updating @last_source and @last_dest as we go through them and mount each copy of the source mount tree @child on a peer @m in @dest_mnt's peer group. After propagate_mnt() handled the peers in @dest_mnt's peer group propagate_mnt() will propagate the source mount tree down the propagation tree that @dest_mnt's peer group propagates to: for (m = next_group(dest_mnt, dest_mnt); m; m = next_group(m, dest_mnt)) { /* everything in that slave group */ n = m; do { ret = propagate_one(n); if (ret) goto out; n = next_peer(n); } while (n != m); } The next_group() helper will recursively walk the destination propagation tree, descending into each propagation group of the propagation tree. The important part is that it takes care to propagate the source mount tree to all peers in the peer group of a propagation group before it propagates to the slaves to those peers in the propagation group. IOW, it creates and mounts copies of the source mount tree that become masters before it creates and mounts copies of the source mount tree that become slaves to these masters. It is important to remember that propagating the source mount tree to each mount @m in the destination propagation tree simply means that we create and mount new copies @child of the source mount tree on @m such that @child->mnt_parent points to @m. Since we know that each node @m in the destination propagation tree headed by @dest_mnt's peer group will be overmounted with a copy of the source mount tree and since we know that the propagation properties of each copy of the source mount tree we create and mount at @m will mostly mirror the propagation properties of @m. We can use that information to create and mount the copies of the source mount tree that become masters before their slaves. The easy case is always when @m and @last_dest are peers in a peer group of a given propagation group. In that case we know that we can simply copy @last_source without having to figure out what the master for the new copy @child of the source mount tree needs to be as we've done that in a previous call to propagate_one(). The hard case is when we're dealing with a slave mount or a shared-slave mount @m in a destination propagation group that we need to create and mount a copy of the source mount tree on. For each propagation group in the destination propagation tree we propagate the source mount tree to we want to make sure that the copies @child of the source mount tree we create and mount on slaves @m pick an ealier copy of the source mount tree that we mounted on a master @m of the destination propagation group as their master. This is a mouthful but as far as we can tell that's the core of it all. But, if we keep track of the masters in the destination propagation tree @m we can use the information to find the correct master for each copy of the source mount tree we create and mount at the slaves in the destination propagation tree @m. Let's walk through the base case as that's still fairly easy to grasp. If we're dealing with the first slave in the propagation group that @dest_mnt is in then we don't yet have marked any masters in the destination propagation tree. We know the master for the first slave to @dest_mnt's peer group is simple @dest_mnt. So we expect this algorithm to yield a copy of the source mount tree that was mounted on a peer in @dest_mnt's peer group as the master for the copy of the source mount tree we want to mount at the first slave @m: for (n = m; ; n = p) { p = n->mnt_master; if (p == dest_master || IS_MNT_MARKED(p)) break; } For the first slave we walk the destination propagation tree all the way up to a peer in @dest_mnt's peer group. IOW, the propagation hierarchy can be walked by walking up the @mnt->mnt_master hierarchy of the destination propagation tree @m. We will ultimately find a peer in @dest_mnt's peer group and thus ultimately @dest_mnt->mnt_master. Btw, here the assumption we listed at the beginning becomes important. Namely, that peers in a peer group pg1 that are slaves in another peer group pg2 appear on the same ->mnt_slave_list. IOW, all slaves who are peers in peer group pg1 point to the same peer in peer group pg2 via their ->mnt_master. Otherwise the termination condition in the code above would be wrong and next_group() would be broken too. So the first iteration sets: n = m; p = n->mnt_master; such that @p now points to a peer or @dest_mnt itself. We walk up one more level since we don't have any marked mounts. So we end up with: n = dest_mnt; p = dest_mnt->mnt_master; If @dest_mnt's peer group is not slave to another peer group then @p is now NULL. If @dest_mnt's peer group is a slave to another peer group then @p now points to @dest_mnt->mnt_master points which is a master outside the propagation tree we're dealing with. Now we need to figure out the master for the copy of the source mount tree we're about to create and mount on the first slave of @dest_mnt's peer group: do { struct mount *parent = last_source->mnt_parent; if (last_source == first_source) break; done = parent->mnt_master == p; if (done && peers(n, parent)) break; last_source = last_source->mnt_master; } while (!done); We know that @last_source->mnt_parent points to @last_dest and @last_dest is the last peer in @dest_mnt's peer group we propagated to in the peer loop in propagate_mnt(). Consequently, @last_source is the last copy we created and mount on that last peer in @dest_mnt's peer group. So @last_source is the master we want to pick. We know that @last_source->mnt_parent->mnt_master points to @last_dest->mnt_master. We also know that @last_dest->mnt_master is either NULL or points to a master outside of the destination propagation tree and so does @p. Hence: done = parent->mnt_master == p; is trivially true in the base condition. We also know that for the first slave mount of @dest_mnt's peer group that @last_dest either points @dest_mnt itself because it was initialized to: last_dest = dest_mnt; at the beginning of propagate_mnt() or it will point to a peer of @dest_mnt in its peer group. In both cases it is guaranteed that on the first iteration @n and @parent are peers (Please note the check for peers here as that's important.): if (done && peers(n, parent)) break; So, as we expected, we select @last_source, which referes to the last copy of the source mount tree we mounted on the last peer in @dest_mnt's peer group, as the master of the first slave in @dest_mnt's peer group. The rest is taken care of by clone_mnt(last_source, ...). We'll skip over that part otherwise this becomes a blogpost. At the end of propagate_mnt() we now mark @m->mnt_master as the first master in the destination propagation tree that is distinct from @dest_mnt->mnt_master. IOW, we mark @dest_mnt itself as a master. By marking @dest_mnt or one of it's peers we are able to easily find it again when we later lookup masters for other copies of the source mount tree we mount copies of the source mount tree on slaves @m to @dest_mnt's peer group. This, in turn allows us to find the master we selected for the copies of the source mount tree we mounted on master in the destination propagation tree again. The important part is to realize that the code makes use of the fact that the last copy of the source mount tree stashed in @last_source was mounted on top of the previous destination propagation node @last_dest. What this means is that @last_source allows us to walk the destination propagation hierarchy the same way each destination propagation node @m does. If we take @last_source, which is the copy of @source_mnt we have mounted on @last_dest in the previous iteration of propagate_one(), then we know @last_source->mnt_parent points to @last_dest but we also know that as we walk through the destination propagation tree that @last_source->mnt_master will point to an earlier copy of the source mount tree we mounted one an earlier destination propagation node @m. IOW, @last_source->mnt_parent will be our hook into the destination propagation tree and each consecutive @last_source->mnt_master will lead us to an earlier propagation node @m via @last_source->mnt_master->mnt_parent. Hence, by walking up @last_source->mnt_master, each of which is mounted on a node that is a master @m in the destination propagation tree we can also walk up the destination propagation hierarchy. So, for each new destination propagation node @m we use the previous copy of @last_source and the fact it's mounted on the previous propagation node @last_dest via @last_source->mnt_master->mnt_parent to determine what the master of the new copy of @last_source needs to be. The goal is to find the _closest_ master that the new copy of the source mount tree we are about to create and mount on a slave @m in the destination propagation tree needs to pick. IOW, we want to find a suitable master in the propagation group. As the propagation structure of the source mount propagation tree we create mirrors the propagation structure of the destination propagation tree we can find @m's closest master - i.e., a marked master - which is a peer in the closest peer group that @m receives propagation from. We store that closest master of @m in @p as before and record the slave to that master in @n We then search for this master @p via @last_source by walking up the master hierarchy starting from the last copy of the source mount tree stored in @last_source that we created and mounted on the previous destination propagation node @m. We will try to find the master by walking @last_source->mnt_master and by comparing @last_source->mnt_master->mnt_parent->mnt_master to @p. If we find @p then we can figure out what earlier copy of the source mount tree needs to be the master for the new copy of the source mount tree we're about to create and mount at the current destination propagation node @m. If @last_source->mnt_master->mnt_parent and @n are peers then we know that the closest master they receive propagation from is @last_source->mnt_master->mnt_parent->mnt_master. If not then the closest immediate peer group that they receive propagation from must be one level higher up. This builds on the earlier clarification at the beginning that all peers in a peer group which are slaves of other peer groups all point to the same ->mnt_master, i.e., appear on the same ->mnt_slave_list, of the closest peer group that they receive propagation from. However, terminating the walk has corner cases. If the closest marked master for a given destination node @m cannot be found by walking up the master hierarchy via @last_source->mnt_master then we need to terminate the walk when we encounter @source_mnt again. This isn't an arbitrary termination. It simply means that the new copy of the source mount tree we're about to create has a copy of the source mount tree we created and mounted on a peer in @dest_mnt's peer group as its master. IOW, @source_mnt is the peer in the closest peer group that the new copy of the source mount tree receives propagation from. We absolutely have to stop @source_mnt because @last_source->mnt_master either points outside the propagation hierarchy we're dealing with or it is NULL because @source_mnt isn't a shared-slave. So continuing the walk past @source_mnt would cause a NULL dereference via @last_source->mnt_master->mnt_parent. And so we have to stop the walk when we encounter @source_mnt again. One scenario where this can happen is when we first handled a series of slaves of @dest_mnt's peer group and then encounter peers in a new peer group that is a slave to @dest_mnt's peer group. We handle them and then we encounter another slave mount to @dest_mnt that is a pure slave to @dest_mnt's peer group. That pure slave will have a peer in @dest_mnt's peer group as its master. Consequently, the new copy of the source mount tree will need to have @source_mnt as it's master. So we walk the propagation hierarchy all the way up to @source_mnt based on @last_source->mnt_master. So terminate on @source_mnt, easy peasy. Except, that the check misses something that the rest of the algorithm already handles. If @dest_mnt has peers in it's peer group the peer loop in propagate_mnt(): for (n = next_peer(dest_mnt); n != dest_mnt; n = next_peer(n)) { ret = propagate_one(n); if (ret) goto out; } will consecutively update @last_source with each previous copy of the source mount tree we created and mounted at the previous peer in @dest_mnt's peer group. So after that loop terminates @last_source will point to whatever copy of the source mount tree was created and mounted on the last peer in @dest_mnt's peer group. Furthermore, if there is even a single additional peer in @dest_mnt's peer group then @last_source will __not__ point to @source_mnt anymore. Because, as we mentioned above, @dest_mnt isn't even handled in this loop but directly in attach_recursive_mnt(). So it can't even accidently come last in that peer loop. So the first time we handle a slave mount @m of @dest_mnt's peer group the copy of the source mount tree we create will make the __last copy of the source mount tree we created and mounted on the last peer in @dest_mnt's peer group the master of the new copy of the source mount tree we create and mount on the first slave of @dest_mnt's peer group__. But this means that the termination condition that checks for @source_mnt is wrong. The @source_mnt cannot be found anymore by propagate_one(). Instead it will find the last copy of the source mount tree we created and mounted for the last peer of @dest_mnt's peer group again. And that is a peer of @source_mnt not @source_mnt itself. IOW, we fail to terminate the loop correctly and ultimately dereference @last_source->mnt_master->mnt_parent. When @source_mnt's peer group isn't slave to another peer group then @last_source->mnt_master is NULL causing the splat below. For example, assume @dest_mnt is a pure shared mount and has three peers in its peer group: =================================================================================== mount-id mount-parent-id peer-group-id =================================================================================== (@dest_mnt) mnt_master[216] 309 297 shared:216 \ (@source_mnt) mnt_master[218]: 609 609 shared:218 (1) mnt_master[216]: 607 605 shared:216 \ (P1) mnt_master[218]: 624 607 shared:218 (2) mnt_master[216]: 576 574 shared:216 \ (P2) mnt_master[218]: 625 576 shared:218 (3) mnt_master[216]: 545 543 shared:216 \ (P3) mnt_master[218]: 626 545 shared:218 After this sequence has been processed @last_source will point to (P3), the copy generated for the third peer in @dest_mnt's peer group we handled. So the copy of the source mount tree (P4) we create and mount on the first slave of @dest_mnt's peer group: =================================================================================== mount-id mount-parent-id peer-group-id =================================================================================== mnt_master[216] 309 297 shared:216 / / (S0) mnt_slave 483 481 master:216 \ \ (P3) mnt_master[218] 626 545 shared:218 \ / \/ (P4) mnt_slave 627 483 master:218 will pick the last copy of the source mount tree (P3) as master, not (S0). When walking the propagation hierarchy via @last_source's master hierarchy we encounter (P3) but not (S0), i.e., @source_mnt. We can fix this in multiple ways: (1) By setting @last_source to @source_mnt after we processed the peers in @dest_mnt's peer group right after the peer loop in propagate_mnt(). (2) By changing the termination condition that relies on finding exactly @source_mnt to finding a peer of @source_mnt. (3) By only moving @last_source when we actually venture into a new peer group or some clever variant thereof. The first two options are minimally invasive and what we want as a fix. The third option is more intrusive but something we'd like to explore in the near future. This passes all LTP tests and specifically the mount propagation testsuite part of it. It also holds up against all known reproducers of this issues. Final words. First, this is a clever but __worringly__ underdocumented algorithm. There isn't a single detailed comment to be found in next_group(), propagate_one() or anywhere else in that file for that matter. This has been a giant pain to understand and work through and a bug like this is insanely difficult to fix without a detailed understanding of what's happening. Let's not talk about the amount of time that was sunk into fixing this. Second, all the cool kids with access to unshare --mount --user --map-root --propagation=unchanged are going to have a lot of fun. IOW, triggerable by unprivileged users while namespace_lock() lock is held. [ 115.848393] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 115.848967] #PF: supervisor read access in kernel mode [ 115.849386] #PF: error_code(0x0000) - not-present page [ 115.849803] PGD 0 P4D 0 [ 115.850012] Oops: 0000 [whatawurst#1] PREEMPT SMP PTI [ 115.850354] CPU: 0 PID: 15591 Comm: mount Not tainted 6.1.0-rc7 whatawurst#3 [ 115.850851] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 115.851510] RIP: 0010:propagate_one.part.0+0x7f/0x1a0 [ 115.851924] Code: 75 eb 4c 8b 05 c2 25 37 02 4c 89 ca 48 8b 4a 10 49 39 d0 74 1e 48 3b 81 e0 00 00 00 74 26 48 8b 92 e0 00 00 00 be 01 00 00 00 <48> 8b 4a 10 49 39 d0 75 e2 40 84 f6 74 38 4c 89 05 84 25 37 02 4d [ 115.853441] RSP: 0018:ffffb8d5443d7d50 EFLAGS: 00010282 [ 115.853865] RAX: ffff8e4d87c41c80 RBX: ffff8e4d88ded780 RCX: ffff8e4da4333a00 [ 115.854458] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8e4d88ded780 [ 115.855044] RBP: ffff8e4d88ded780 R08: ffff8e4da4338000 R09: ffff8e4da43388c0 [ 115.855693] R10: 0000000000000002 R11: ffffb8d540158000 R12: ffffb8d5443d7da8 [ 115.856304] R13: ffff8e4d88ded780 R14: 0000000000000000 R15: 0000000000000000 [ 115.856859] FS: 00007f92c90c9800(0000) GS:ffff8e4dfdc00000(0000) knlGS:0000000000000000 [ 115.857531] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 115.858006] CR2: 0000000000000010 CR3: 0000000022f4c002 CR4: 00000000000706f0 [ 115.858598] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 115.859393] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 115.860099] Call Trace: [ 115.860358] <TASK> [ 115.860535] propagate_mnt+0x14d/0x190 [ 115.860848] attach_recursive_mnt+0x274/0x3e0 [ 115.861212] path_mount+0x8c8/0xa60 [ 115.861503] __x64_sys_mount+0xf6/0x140 [ 115.861819] do_syscall_64+0x5b/0x80 [ 115.862117] ? do_faccessat+0x123/0x250 [ 115.862435] ? syscall_exit_to_user_mode+0x17/0x40 [ 115.862826] ? do_syscall_64+0x67/0x80 [ 115.863133] ? syscall_exit_to_user_mode+0x17/0x40 [ 115.863527] ? do_syscall_64+0x67/0x80 [ 115.863835] ? do_syscall_64+0x67/0x80 [ 115.864144] ? do_syscall_64+0x67/0x80 [ 115.864452] ? exc_page_fault+0x70/0x170 [ 115.864775] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 115.865187] RIP: 0033:0x7f92c92b0ebe [ 115.865480] Code: 48 8b 0d 75 4f 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 42 4f 0c 00 f7 d8 64 89 01 48 [ 115.866984] RSP: 002b:00007fff000aa728 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 115.867607] RAX: ffffffffffffffda RBX: 000055a77888d6b0 RCX: 00007f92c92b0ebe [ 115.868240] RDX: 000055a77888d8e0 RSI: 000055a77888e6e0 RDI: 000055a77888e620 [ 115.868823] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 115.869403] R10: 0000000000001000 R11: 0000000000000246 R12: 000055a77888e620 [ 115.869994] R13: 000055a77888d8e0 R14: 00000000ffffffff R15: 00007f92c93e4076 [ 115.870581] </TASK> [ 115.870763] Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set rfkill nf_tables nfnetlink qrtr snd_intel8x0 sunrpc snd_ac97_codec ac97_bus snd_pcm snd_timer intel_rapl_msr intel_rapl_common snd vboxguest intel_powerclamp video rapl joydev soundcore i2c_piix4 wmi fuse zram xfs vmwgfx crct10dif_pclmul crc32_pclmul crc32c_intel polyval_clmulni polyval_generic drm_ttm_helper ttm e1000 ghash_clmulni_intel serio_raw ata_generic pata_acpi scsi_dh_rdac scsi_dh_emc scsi_dh_alua dm_multipath [ 115.875288] CR2: 0000000000000010 [ 115.875641] ---[ end trace 0000000000000000 ]--- [ 115.876135] RIP: 0010:propagate_one.part.0+0x7f/0x1a0 [ 115.876551] Code: 75 eb 4c 8b 05 c2 25 37 02 4c 89 ca 48 8b 4a 10 49 39 d0 74 1e 48 3b 81 e0 00 00 00 74 26 48 8b 92 e0 00 00 00 be 01 00 00 00 <48> 8b 4a 10 49 39 d0 75 e2 40 84 f6 74 38 4c 89 05 84 25 37 02 4d [ 115.878086] RSP: 0018:ffffb8d5443d7d50 EFLAGS: 00010282 [ 115.878511] RAX: ffff8e4d87c41c80 RBX: ffff8e4d88ded780 RCX: ffff8e4da4333a00 [ 115.879128] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8e4d88ded780 [ 115.879715] RBP: ffff8e4d88ded780 R08: ffff8e4da4338000 R09: ffff8e4da43388c0 [ 115.880359] R10: 0000000000000002 R11: ffffb8d540158000 R12: ffffb8d5443d7da8 [ 115.880962] R13: ffff8e4d88ded780 R14: 0000000000000000 R15: 0000000000000000 [ 115.881548] FS: 00007f92c90c9800(0000) GS:ffff8e4dfdc00000(0000) knlGS:0000000000000000 [ 115.882234] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 115.882713] CR2: 0000000000000010 CR3: 0000000022f4c002 CR4: 00000000000706f0 [ 115.883314] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 115.883966] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Fixes: f2ebb3a ("smarter propagate_mnt()") Fixes: 5ec0811 ("propogate_mnt: Handle the first propogated copy being a slave") Cc: <stable@vger.kernel.org> Reported-by: Ditang Chen <ditang.c@gmail.com> Signed-off-by: Seth Forshee (Digital Ocean) <sforshee@kernel.org> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ulrich Hecht <uli+cip@fpond.eu>

[ Upstream commit b18cba09e374637a0a3759d856a6bca94c133952 ] Commit 9130b8d ("SUNRPC: allow for upcalls for the same uid but different gss service") introduced `auth` argument to __gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL since it (and auth->service) was not (yet) determined. When multiple upcalls with the same uid and different service are ongoing, it could happen that __gss_find_upcall(), which returns the first match found in the pipe->in_downcall list, could not find the correct gss_msg corresponding to the downcall we are looking for. Moreover, it might return a msg which is not sent to rpc.gssd yet. We could see mount.nfs process hung in D state with multiple mount.nfs are executed in parallel. The call trace below is of CentOS 7.9 kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/ elrepo kernel-ml-6.0.7-1.el7. PID: 71258 TASK: ffff91ebd4be0000 CPU: 36 COMMAND: "mount.nfs" #0 [ffff9203ca3234f8] __schedule at ffffffffa3b8899f whatawurst#1 [ffff9203ca323580] schedule at ffffffffa3b88eb9 whatawurst#2 [ffff9203ca323590] gss_cred_init at ffffffffc0355818 [auth_rpcgss] whatawurst#3 [ffff9203ca323658] rpcauth_lookup_credcache at ffffffffc0421ebc [sunrpc] whatawurst#4 [ffff9203ca3236d8] gss_lookup_cred at ffffffffc0353633 [auth_rpcgss] whatawurst#5 [ffff9203ca3236e8] rpcauth_lookupcred at ffffffffc0421581 [sunrpc] whatawurst#6 [ffff9203ca323740] rpcauth_refreshcred at ffffffffc04223d3 [sunrpc] whatawurst#7 [ffff9203ca3237a0] call_refresh at ffffffffc04103dc [sunrpc] whatawurst#8 [ffff9203ca3237b8] __rpc_execute at ffffffffc041e1c9 [sunrpc] whatawurst#9 [ffff9203ca323820] rpc_execute at ffffffffc0420a48 [sunrpc] The scenario is like this. Let's say there are two upcalls for services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe. When rpc.gssd reads pipe to get the upcall msg corresponding to service B from pipe->pipe and then writes the response, in gss_pipe_downcall the msg corresponding to service A will be picked because only uid is used to find the msg and it is before the one for B in pipe->in_downcall. And the process waiting for the msg corresponding to service A will be woken up. Actual scheduing of that process might be after rpc.gssd processes the next msg. In rpc_pipe_generic_upcall it clears msg->errno (for A). The process is scheduled to see gss_msg->ctx == NULL and gss_msg->msg.errno == 0, therefore it cannot break the loop in gss_create_upcall and is never woken up after that. This patch adds a simple check to ensure that a msg which is not sent to rpc.gssd yet is not chosen as the matching upcall upon receiving a downcall. Signed-off-by: minoura makoto <minoura@valinux.co.jp> Signed-off-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Tested-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Cc: Trond Myklebust <trondmy@hammerspace.com> Fixes: 9130b8d ("SUNRPC: allow for upcalls for same uid but different gss service") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org> [uli: backport to 4.4] Signed-off-by: Ulrich Hecht <uli+cip@fpond.eu>

[ Upstream commit 6c4ca03bd890566d873e3593b32d034bf2f5a087 ] During EEH error injection testing, a deadlock was encountered in the tg3 driver when tg3_io_error_detected() was attempting to cancel outstanding reset tasks: crash> foreach UN bt ... PID: 159 TASK: c0000000067c6000 CPU: 8 COMMAND: "eehd" ... whatawurst#5 [c00000000681f990] __cancel_work_timer at c00000000019fd18 whatawurst#6 [c00000000681fa30] tg3_io_error_detected at c00800000295f098 [tg3] whatawurst#7 [c00000000681faf0] eeh_report_error at c00000000004e25c ... PID: 290 TASK: c000000036e5f800 CPU: 6 COMMAND: "kworker/6:1" ... whatawurst#4 [c00000003721fbc0] rtnl_lock at c000000000c940d8 whatawurst#5 [c00000003721fbe0] tg3_reset_task at c008000002969358 [tg3] whatawurst#6 [c00000003721fc60] process_one_work at c00000000019e5c4 ... PID: 296 TASK: c000000037a65800 CPU: 21 COMMAND: "kworker/21:1" ... whatawurst#4 [c000000037247bc0] rtnl_lock at c000000000c940d8 whatawurst#5 [c000000037247be0] tg3_reset_task at c008000002969358 [tg3] whatawurst#6 [c000000037247c60] process_one_work at c00000000019e5c4 ... PID: 655 TASK: c000000036f49000 CPU: 16 COMMAND: "kworker/16:2" ...:1 whatawurst#4 [c0000000373ebbc0] rtnl_lock at c000000000c940d8 whatawurst#5 [c0000000373ebbe0] tg3_reset_task at c008000002969358 [tg3] whatawurst#6 [c0000000373ebc60] process_one_work at c00000000019e5c4 ... Code inspection shows that both tg3_io_error_detected() and tg3_reset_task() attempt to acquire the RTNL lock at the beginning of their code blocks. If tg3_reset_task() should happen to execute between the times when tg3_io_error_deteced() acquires the RTNL lock and tg3_reset_task_cancel() is called, a deadlock will occur. Moving tg3_reset_task_cancel() call earlier within the code block, prior to acquiring RTNL, prevents this from happening, but also exposes another deadlock issue where tg3_reset_task() may execute AFTER tg3_io_error_detected() has executed: crash> foreach UN bt PID: 159 TASK: c0000000067d2000 CPU: 9 COMMAND: "eehd" ... whatawurst#4 [c000000006867a60] rtnl_lock at c000000000c940d8 whatawurst#5 [c000000006867a80] tg3_io_slot_reset at c0080000026c2ea8 [tg3] whatawurst#6 [c000000006867b00] eeh_report_reset at c00000000004de88 ... PID: 363 TASK: c000000037564000 CPU: 6 COMMAND: "kworker/6:1" ... whatawurst#3 [c000000036c1bb70] msleep at c000000000259e6c whatawurst#4 [c000000036c1bba0] napi_disable at c000000000c6b848 whatawurst#5 [c000000036c1bbe0] tg3_reset_task at c0080000026d942c [tg3] whatawurst#6 [c000000036c1bc60] process_one_work at c00000000019e5c4 ... This issue can be avoided by aborting tg3_reset_task() if EEH error recovery is already in progress. Fixes: db84bf4 ("tg3: tg3_reset_task() needs to use rtnl_lock to synchronize") Signed-off-by: David Christensen <drc@linux.vnet.ibm.com> Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Link: https://lore.kernel.org/r/20230124185339.225806-1-drc@linux.vnet.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Ulrich Hecht <uli+cip@fpond.eu>

commit 60eed1e3d45045623e46944ebc7c42c30a4350f0 upstream. code path: ocfs2_ioctl_move_extents ocfs2_move_extents ocfs2_defrag_extent __ocfs2_move_extent + ocfs2_journal_access_di + ocfs2_split_extent //sub-paths call jbd2_journal_restart + ocfs2_journal_dirty //crash by jbs2 ASSERT crash stacks: PID: 11297 TASK: ffff974a676dcd00 CPU: 67 COMMAND: "defragfs.ocfs2" #0 [ffffb25d8dad3900] machine_kexec at ffffffff8386fe01 whatawurst#1 [ffffb25d8dad3958] __crash_kexec at ffffffff8395959d whatawurst#2 [ffffb25d8dad3a20] crash_kexec at ffffffff8395a45d whatawurst#3 [ffffb25d8dad3a38] oops_end at ffffffff83836d3f whatawurst#4 [ffffb25d8dad3a58] do_trap at ffffffff83833205 whatawurst#5 [ffffb25d8dad3aa0] do_invalid_op at ffffffff83833aa6 whatawurst#6 [ffffb25d8dad3ac0] invalid_op at ffffffff84200d18 [exception RIP: jbd2_journal_dirty_metadata+0x2ba] RIP: ffffffffc09ca54a RSP: ffffb25d8dad3b70 RFLAGS: 00010207 RAX: 0000000000000000 RBX: ffff9706eedc5248 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffff97337029ea28 RDI: ffff9706eedc5250 RBP: ffff9703c3520200 R8: 000000000f46b0b2 R9: 0000000000000000 R10: 0000000000000001 R11: 00000001000000fe R12: ffff97337029ea28 R13: 0000000000000000 R14: ffff9703de59bf60 R15: ffff9706eedc5250 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 whatawurst#7 [ffffb25d8dad3ba8] ocfs2_journal_dirty at ffffffffc137fb95 [ocfs2] whatawurst#8 [ffffb25d8dad3be8] __ocfs2_move_extent at ffffffffc139a950 [ocfs2] whatawurst#9 [ffffb25d8dad3c80] ocfs2_defrag_extent at ffffffffc139b2d2 [ocfs2] Analysis This bug has the same root cause of 'commit 7f27ec9 ("ocfs2: call ocfs2_journal_access_di() before ocfs2_journal_dirty() in ocfs2_write_end_nolock()")'. For this bug, jbd2_journal_restart() is called by ocfs2_split_extent() during defragmenting. How to fix For ocfs2_split_extent() can handle journal operations totally by itself. Caller doesn't need to call journal access/dirty pair, and caller only needs to call journal start/stop pair. The fix method is to remove journal access/dirty from __ocfs2_move_extent(). The discussion for this patch: https://oss.oracle.com/pipermail/ocfs2-devel/2023-February/000647.html Link: https://lkml.kernel.org/r/20230217003717.32469-1-heming.zhao@suse.com Signed-off-by: Heming Zhao <heming.zhao@suse.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ulrich Hecht <uli+cip@fpond.eu>

[ Upstream commit 05bb0167c80b8f93c6a4e0451b7da9b96db990c2 ] ACPICA commit 770653e3ba67c30a629ca7d12e352d83c2541b1e Before this change we see the following UBSAN stack trace in Fuchsia: #0 0x000021e4213b3302 in acpi_ds_init_aml_walk(struct acpi_walk_state*, union acpi_parse_object*, struct acpi_namespace_node*, u8*, u32, struct acpi_evaluate_info*, u8) ../../third_party/acpica/source/components/dispatcher/dswstate.c:682 <platform-bus-x86.so>+0x233302 whatawurst#1.2 0x000020d0f660777f in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x3d77f whatawurst#1.1 0x000020d0f660777f in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x3d77f whatawurst#1 0x000020d0f660777f in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:387 <libclang_rt.asan.so>+0x3d77f whatawurst#2 0x000020d0f660b96d in handlepointer_overflow_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:809 <libclang_rt.asan.so>+0x4196d whatawurst#3 0x000020d0f660b50d in compiler-rt/lib/ubsan/ubsan_handlers.cpp:815 <libclang_rt.asan.so>+0x4150d whatawurst#4 0x000021e4213b3302 in acpi_ds_init_aml_walk(struct acpi_walk_state*, union acpi_parse_object*, struct acpi_namespace_node*, u8*, u32, struct acpi_evaluate_info*, u8) ../../third_party/acpica/source/components/dispatcher/dswstate.c:682 <platform-bus-x86.so>+0x233302 whatawurst#5 0x000021e4213e2369 in acpi_ds_call_control_method(struct acpi_thread_state*, struct acpi_walk_state*, union acpi_parse_object*) ../../third_party/acpica/source/components/dispatcher/dsmethod.c:605 <platform-bus-x86.so>+0x262369 whatawurst#6 0x000021e421437fac in acpi_ps_parse_aml(struct acpi_walk_state*) ../../third_party/acpica/source/components/parser/psparse.c:550 <platform-bus-x86.so>+0x2b7fac whatawurst#7 0x000021e4214464d2 in acpi_ps_execute_method(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/parser/psxface.c:244 <platform-bus-x86.so>+0x2c64d2 whatawurst#8 0x000021e4213aa052 in acpi_ns_evaluate(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/namespace/nseval.c:250 <platform-bus-x86.so>+0x22a052 whatawurst#9 0x000021e421413dd8 in acpi_ns_init_one_device(acpi_handle, u32, void*, void**) ../../third_party/acpica/source/components/namespace/nsinit.c:735 <platform-bus-x86.so>+0x293dd8 whatawurst#10 0x000021e421429e98 in acpi_ns_walk_namespace(acpi_object_type, acpi_handle, u32, u32, acpi_walk_callback, acpi_walk_callback, void*, void**) ../../third_party/acpica/source/components/namespace/nswalk.c:298 <platform-bus-x86.so>+0x2a9e98 whatawurst#11 0x000021e4214131ac in acpi_ns_initialize_devices(u32) ../../third_party/acpica/source/components/namespace/nsinit.c:268 <platform-bus-x86.so>+0x2931ac whatawurst#12 0x000021e42147c40d in acpi_initialize_objects(u32) ../../third_party/acpica/source/components/utilities/utxfinit.c:304 <platform-bus-x86.so>+0x2fc40d whatawurst#13 0x000021e42126d603 in acpi::acpi_impl::initialize_acpi(acpi::acpi_impl*) ../../src/devices/board/lib/acpi/acpi-impl.cc:224 <platform-bus-x86.so>+0xed603 Add a simple check that avoids incrementing a pointer by zero, but otherwise behaves as before. Note that our findings are against ACPICA 20221020, but the same code exists on master. Link: acpica/acpica@770653e3 Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Ulrich Hecht <uli+cip@fpond.eu>

Our static-static calculation returns a failure if the public key is of low order. We check for this when peers are added, and don't allow them to be added if they're low order, except in the case where we haven't yet been given a private key. In that case, we would defer the removal of the peer until we're given a private key, since at that point we're doing new static-static calculations which incur failures we can act on. This meant, however, that we wound up removing peers rather late in the configuration flow. Syzkaller points out that peer_remove calls flush_workqueue, which in turn might then wait for sending a handshake initiation to complete. Since handshake initiation needs the static identity lock, holding the static identity lock while calling peer_remove can result in a rare deadlock. We have precisely this case in this situation of late-stage peer removal based on an invalid public key. We can't drop the lock when removing, because then incoming handshakes might interact with a bogus static-static calculation. While the band-aid patch for this would involve breaking up the peer removal into two steps like wg_peer_remove_all does, in order to solve the locking issue, there's actually a much more elegant way of fixing this: If the static-static calculation succeeds with one private key, it *must* succeed with all others, because all 32-byte strings map to valid private keys, thanks to clamping. That means we can get rid of this silly dance and locking headaches of removing peers late in the configuration flow, and instead just reject them early on, regardless of whether the device has yet been assigned a private key. For the case where the device doesn't yet have a private key, we safely use zeros just for the purposes of checking for low order points by way of checking the output of the calculation. The following PoC will trigger the deadlock: ip link add wg0 type wireguard ip addr add 10.0.0.1/24 dev wg0 ip link set wg0 up ping -f 10.0.0.2 & while true; do wg set wg0 private-key /dev/null peer AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA= allowed-ips 10.0.0.0/24 endpoint 10.0.0.3:1234 wg set wg0 private-key <(echo AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=) done [ 0.949105] ====================================================== [ 0.949550] WARNING: possible circular locking dependency detected [ 0.950143] 5.5.0-debug+ whatawurst#18 Not tainted [ 0.950431] ------------------------------------------------------ [ 0.950959] wg/89 is trying to acquire lock: [ 0.951252] ffff8880333e2128 ((wq_completion)wg-kex-wg0){+.+.}, at: flush_workqueue+0xe3/0x12f0 [ 0.951865] [ 0.951865] but task is already holding lock: [ 0.952280] ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0 [ 0.953011] [ 0.953011] which lock already depends on the new lock. [ 0.953011] [ 0.953651] [ 0.953651] the existing dependency chain (in reverse order) is: [ 0.954292] [ 0.954292] -> whatawurst#2 (&wg->static_identity.lock){++++}: [ 0.954804] lock_acquire+0x127/0x350 [ 0.955133] down_read+0x83/0x410 [ 0.955428] wg_noise_handshake_create_initiation+0x97/0x700 [ 0.955885] wg_packet_send_handshake_initiation+0x13a/0x280 [ 0.956401] wg_packet_handshake_send_worker+0x10/0x20 [ 0.956841] process_one_work+0x806/0x1500 [ 0.957167] worker_thread+0x8c/0xcb0 [ 0.957549] kthread+0x2ee/0x3b0 [ 0.957792] ret_from_fork+0x24/0x30 [ 0.958234] [ 0.958234] -> whatawurst#1 ((work_completion)(&peer->transmit_handshake_work)){+.+.}: [ 0.958808] lock_acquire+0x127/0x350 [ 0.959075] process_one_work+0x7ab/0x1500 [ 0.959369] worker_thread+0x8c/0xcb0 [ 0.959639] kthread+0x2ee/0x3b0 [ 0.959896] ret_from_fork+0x24/0x30 [ 0.960346] [ 0.960346] -> #0 ((wq_completion)wg-kex-wg0){+.+.}: [ 0.960945] check_prev_add+0x167/0x1e20 [ 0.961351] __lock_acquire+0x2012/0x3170 [ 0.961725] lock_acquire+0x127/0x350 [ 0.961990] flush_workqueue+0x106/0x12f0 [ 0.962280] peer_remove_after_dead+0x160/0x220 [ 0.962600] wg_set_device+0xa24/0xcc0 [ 0.962994] genl_rcv_msg+0x52f/0xe90 [ 0.963298] netlink_rcv_skb+0x111/0x320 [ 0.963618] genl_rcv+0x1f/0x30 [ 0.963853] netlink_unicast+0x3f6/0x610 [ 0.964245] netlink_sendmsg+0x700/0xb80 [ 0.964586] __sys_sendto+0x1dd/0x2c0 [ 0.964854] __x64_sys_sendto+0xd8/0x1b0 [ 0.965141] do_syscall_64+0x90/0xd9a [ 0.965408] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 0.965769] [ 0.965769] other info that might help us debug this: [ 0.965769] [ 0.966337] Chain exists of: [ 0.966337] (wq_completion)wg-kex-wg0 --> (work_completion)(&peer->transmit_handshake_work) --> &wg->static_identity.lock [ 0.966337] [ 0.967417] Possible unsafe locking scenario: [ 0.967417] [ 0.967836] CPU0 CPU1 [ 0.968155] ---- ---- [ 0.968497] lock(&wg->static_identity.lock); [ 0.968779] lock((work_completion)(&peer->transmit_handshake_work)); [ 0.969345] lock(&wg->static_identity.lock); [ 0.969809] lock((wq_completion)wg-kex-wg0); [ 0.970146] [ 0.970146] *** DEADLOCK *** [ 0.970146] [ 0.970531] 5 locks held by wg/89: [ 0.970908] #0: ffffffff827433c8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 [ 0.971400] whatawurst#1: ffffffff82743480 (genl_mutex){+.+.}, at: genl_rcv_msg+0x642/0xe90 [ 0.971924] whatawurst#2: ffffffff827160c0 (rtnl_mutex){+.+.}, at: wg_set_device+0x9f/0xcc0 [ 0.972488] whatawurst#3: ffff888032819de0 (&wg->device_update_lock){+.+.}, at: wg_set_device+0xb0/0xcc0 [ 0.973095] whatawurst#4: ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0 [ 0.973653] [ 0.973653] stack backtrace: [ 0.973932] CPU: 1 PID: 89 Comm: wg Not tainted 5.5.0-debug+ whatawurst#18 [ 0.974476] Call Trace: [ 0.974638] dump_stack+0x97/0xe0 [ 0.974869] check_noncircular+0x312/0x3e0 [ 0.975132] ? print_circular_bug+0x1f0/0x1f0 [ 0.975410] ? __kernel_text_address+0x9/0x30 [ 0.975727] ? unwind_get_return_address+0x51/0x90 [ 0.976024] check_prev_add+0x167/0x1e20 [ 0.976367] ? graph_lock+0x70/0x160 [ 0.976682] __lock_acquire+0x2012/0x3170 [ 0.976998] ? register_lock_class+0x1140/0x1140 [ 0.977323] lock_acquire+0x127/0x350 [ 0.977627] ? flush_workqueue+0xe3/0x12f0 [ 0.977890] flush_workqueue+0x106/0x12f0 [ 0.978147] ? flush_workqueue+0xe3/0x12f0 [ 0.978410] ? find_held_lock+0x2c/0x110 [ 0.978662] ? lock_downgrade+0x6e0/0x6e0 [ 0.978919] ? queue_rcu_work+0x60/0x60 [ 0.979166] ? netif_napi_del+0x151/0x3b0 [ 0.979501] ? peer_remove_after_dead+0x160/0x220 [ 0.979871] peer_remove_after_dead+0x160/0x220 [ 0.980232] wg_set_device+0xa24/0xcc0 [ 0.980516] ? deref_stack_reg+0x8e/0xc0 [ 0.980801] ? set_peer+0xe10/0xe10 [ 0.981040] ? __ww_mutex_check_waiters+0x150/0x150 [ 0.981430] ? __nla_validate_parse+0x163/0x270 [ 0.981719] ? genl_family_rcv_msg_attrs_parse+0x13f/0x310 [ 0.982078] genl_rcv_msg+0x52f/0xe90 [ 0.982348] ? genl_family_rcv_msg_attrs_parse+0x310/0x310 [ 0.982690] ? register_lock_class+0x1140/0x1140 [ 0.983049] netlink_rcv_skb+0x111/0x320 [ 0.983298] ? genl_family_rcv_msg_attrs_parse+0x310/0x310 [ 0.983645] ? netlink_ack+0x880/0x880 [ 0.983888] genl_rcv+0x1f/0x30 [ 0.984168] netlink_unicast+0x3f6/0x610 [ 0.984443] ? netlink_detachskb+0x60/0x60 [ 0.984729] ? find_held_lock+0x2c/0x110 [ 0.984976] netlink_sendmsg+0x700/0xb80 [ 0.985220] ? netlink_broadcast_filtered+0xa60/0xa60 [ 0.985533] __sys_sendto+0x1dd/0x2c0 [ 0.985763] ? __x64_sys_getpeername+0xb0/0xb0 [ 0.986039] ? sockfd_lookup_light+0x17/0x160 [ 0.986397] ? __sys_recvmsg+0x8c/0xf0 [ 0.986711] ? __sys_recvmsg_sock+0xd0/0xd0 [ 0.987018] __x64_sys_sendto+0xd8/0x1b0 [ 0.987283] ? lockdep_hardirqs_on+0x39b/0x5a0 [ 0.987666] do_syscall_64+0x90/0xd9a [ 0.987903] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 0.988223] RIP: 0033:0x7fe77c12003e [ 0.988508] Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 4 [ 0.989666] RSP: 002b:00007fffada2ed58 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 0.990137] RAX: ffffffffffffffda RBX: 00007fe77c159d48 RCX: 00007fe77c12003e [ 0.990583] RDX: 0000000000000040 RSI: 000055fd1d38e020 RDI: 0000000000000004 [ 0.991091] RBP: 000055fd1d38e020 R08: 000055fd1cb63358 R09: 000000000000000c [ 0.991568] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000002c [ 0.992014] R13: 0000000000000004 R14: 000055fd1d38e020 R15: 0000000000000001 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> (cherry picked from commit ec31c26) Bug: 152722841 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com> Change-Id: I860bfac72c98c8c9b26f4490b4f346dc67892f87

[ Upstream commit d8b5411 ] Shubham was recently asking on netdev why in arm64 JIT we don't multiply the index for accessing the tail call map by 8. That led me into testing out arm64 JIT wrt tail calls and it turned out I got a NULL pointer dereference on the tail call. The buggy access is at: prog = array->ptrs[index]; if (prog == NULL) goto out; [...] 00000060: d2800e0a mov x10, #0x70 // #112 00000064: f86a682a ldr x10, [x1,x10] 00000068: f862694b ldr x11, [x10,x2] 0000006c: b40000ab cbz x11, 0x00000080 [...] The code triggering the crash is f862694b. x1 at the time contains the address of the bpf array, x10 offsetof(struct bpf_array, ptrs). Meaning, above we load the pointer to the program at map slot 0 into x10. x10 can then be NULL if the slot is not occupied, which we later on try to access with a user given offset in x2 that is the map index. Fix this by emitting the following instead: [...] 00000060: d2800e0a mov x10, #0x70 // #112 00000064: 8b0a002a add x10, x1, x10 00000068: d37df04b lsl x11, x2, whatawurst#3 0000006c: f86b694b ldr x11, [x10,x11] 00000070: b40000ab cbz x11, 0x00000084 [...] This basically adds the offset to ptrs to the base address of the bpf array we got and we later on access the map with an index * 8 offset relative to that. The tail call map itself is basically one large area with meta data at the head followed by the array of prog pointers. This makes tail calls working again, tested on Cavium ThunderX ARMv8. Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") Reported-by: Shubham Bansal <illusionist.neo@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ upstream commit 16338a9 ] I recently noticed a crash on arm64 when feeding a bogus index into BPF tail call helper. The crash would not occur when the interpreter is used, but only in case of JIT. Output looks as follows: [ 347.007486] Unable to handle kernel paging request at virtual address fffb850e96492510 [...] [ 347.043065] [fffb850e96492510] address between user and kernel address ranges [ 347.050205] Internal error: Oops: 96000004 [whatawurst#1] SMP [...] [ 347.190829] x13: 0000000000000000 x12: 0000000000000000 [ 347.196128] x11: fffc047ebe782800 x10: ffff808fd7d0fd10 [ 347.201427] x9 : 0000000000000000 x8 : 0000000000000000 [ 347.206726] x7 : 0000000000000000 x6 : 001c991738000000 [ 347.212025] x5 : 0000000000000018 x4 : 000000000000ba5a [ 347.217325] x3 : 00000000000329c4 x2 : ffff808fd7cf0500 [ 347.222625] x1 : ffff808fd7d0fc00 x0 : ffff808fd7cf0500 [ 347.227926] Process test_verifier (pid: 4548, stack limit = 0x000000007467fa61) [ 347.235221] Call trace: [ 347.237656] 0xffff000002f3a4fc [ 347.240784] bpf_test_run+0x78/0xf8 [ 347.244260] bpf_prog_test_run_skb+0x148/0x230 [ 347.248694] SyS_bpf+0x77c/0x1110 [ 347.251999] el0_svc_naked+0x30/0x34 [ 347.255564] Code: 9100075a d280220a 8b0a002a d37df04b (f86b694b) [...] In this case the index used in BPF r3 is the same as in r1 at the time of the call, meaning we fed a pointer as index; here, it had the value 0xffff808fd7cf0500 which sits in x2. While I found tail calls to be working in general (also for hitting the error cases), I noticed the following in the code emission: # bpftool p d j i 988 [...] 38: ldr w10, [x1,x10] 3c: cmp w2, w10 40: b.ge 0x000000000000007c <-- signed cmp 44: mov x10, #0x20 // whatawurst#32 48: cmp x26, x10 4c: b.gt 0x000000000000007c 50: add x26, x26, #0x1 54: mov x10, #0x110 // #272 58: add x10, x1, x10 5c: lsl x11, x2, whatawurst#3 60: ldr x11, [x10,x11] <-- faulting insn (f86b694b) 64: cbz x11, 0x000000000000007c [...] Meaning, the tests passed because commit ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") was using signed compares instead of unsigned which as a result had the test wrongly passing. Change this but also the tail call count test both into unsigned and cap the index as u32. Latter we did as well in 90caccd ("bpf: fix bpf_tail_call() x64 JIT") and is needed in addition here, too. Tested on HiSilicon Hi1616. Result after patch: # bpftool p d j i 268 [...] 38: ldr w10, [x1,x10] 3c: add w2, w2, #0x0 40: cmp w2, w10 44: b.cs 0x0000000000000080 48: mov x10, #0x20 // whatawurst#32 4c: cmp x26, x10 50: b.hi 0x0000000000000080 54: add x26, x26, #0x1 58: mov x10, #0x110 // #272 5c: add x10, x1, x10 60: lsl x11, x2, whatawurst#3 64: ldr x11, [x10,x11] 68: cbz x11, 0x0000000000000080 [...] Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 9c6d778800b921bde3bff3cff5003d1650f942d1 upstream. Automatic kernel fuzzing revealed a recursive locking violation in usb-storage: ============================================ WARNING: possible recursive locking detected 5.18.0 whatawurst#3 Not tainted -------------------------------------------- kworker/1:3/1205 is trying to acquire lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 but task is already holding lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 ... stack backtrace: CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 whatawurst#3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2988 [inline] check_deadlock kernel/locking/lockdep.c:3031 [inline] validate_chain kernel/locking/lockdep.c:3816 [inline] __lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747 usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109 r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622 usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:545 [inline] device_remove+0x11f/0x170 drivers/base/dd.c:537 __device_release_driver drivers/base/dd.c:1222 [inline] device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248 usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627 usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118 usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114 This turned out not to be an error in usb-storage but rather a nested device reset attempt. That is, as the rtl8712 driver was being unbound from a composite device in preparation for an unrelated USB reset (that driver does not have pre_reset or post_reset callbacks), its ->remove routine called usb_reset_device() -- thus nesting one reset call within another. Performing a reset as part of disconnect processing is a questionable practice at best. However, the bug report points out that the USB core does not have any protection against nested resets. Adding a reset_in_progress flag and testing it will prevent such errors in the future. Link: https://lore.kernel.org/all/CAB7eexKUpvX-JNiLzhXBDWgfg2T9e9_0Tw4HQ6keN==voRbP0g@mail.gmail.com/ Cc: stable@vger.kernel.org Reported-and-tested-by: Rondreis <linhaoguo86@gmail.com> Change-Id: I0812c3b2aec376fffddb3e03f3351f66ff76bcc6 Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Link: https://lore.kernel.org/r/YwkflDxvg0KWqyZK@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit f8bbc07ac535593139c875ffa19af924b1084540 ] vhost_worker will call tun call backs to receive packets. If too many illegal packets arrives, tun_do_read will keep dumping packet contents. When console is enabled, it will costs much more cpu time to dump packet and soft lockup will be detected. net_ratelimit mechanism can be used to limit the dumping rate. PID: 33036 TASK: ffff949da6f20000 CPU: 23 COMMAND: "vhost-32980" #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253 whatawurst#1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3 whatawurst#2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e whatawurst#3 [fffffe00003fced0] do_nmi at ffffffff8922660d whatawurst#4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663 [exception RIP: io_serial_in+20] RIP: ffffffff89792594 RSP: ffffa655314979e8 RFLAGS: 00000002 RAX: ffffffff89792500 RBX: ffffffff8af428a0 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff8af428a0 RBP: 0000000000002710 R8: 0000000000000004 R9: 000000000000000f R10: 0000000000000000 R11: ffffffff8acbf64f R12: 0000000000000020 R13: ffffffff8acbf698 R14: 0000000000000058 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 whatawurst#5 [ffffa655314979e8] io_serial_in at ffffffff89792594 whatawurst#6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470 whatawurst#7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6 whatawurst#8 [ffffa65531497a20] uart_console_write at ffffffff8978b605 whatawurst#9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558 whatawurst#10 [ffffa65531497ac8] console_unlock at ffffffff89316124 whatawurst#11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07 whatawurst#12 [ffffa65531497b68] printk at ffffffff89318306 whatawurst#13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765 whatawurst#14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun] whatawurst#15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun] whatawurst#16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net] whatawurst#17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost] whatawurst#18 [ffffa65531497f10] kthread at ffffffff892d2e72 whatawurst#19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors") Signed-off-by: Lei Chen <lei.chen@smartx.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Acked-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> [uli: backport to 4.4] Signed-off-by: Ulrich Hecht <uli@kernel.org>

commit 22f00812862564b314784167a89f27b444f82a46 upstream. The syzbot fuzzer found that the interrupt-URB completion callback in the cdc-wdm driver was taking too long, and the driver's immediate resubmission of interrupt URBs with -EPROTO status combined with the dummy-hcd emulation to cause a CPU lockup: cdc_wdm 1-1:1.0: nonzero urb status received: -71 cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625] CPU#0 Utilization every 4s during lockup: whatawurst#1: 98% system, 0% softirq, 3% hardirq, 0% idle whatawurst#2: 98% system, 0% softirq, 3% hardirq, 0% idle whatawurst#3: 98% system, 0% softirq, 3% hardirq, 0% idle whatawurst#4: 98% system, 0% softirq, 3% hardirq, 0% idle whatawurst#5: 98% system, 1% softirq, 3% hardirq, 0% idle Modules linked in: irq event stamp: 73096 hardirqs last enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline] hardirqs last enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994 hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline] hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551 softirqs last enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline] softirqs last enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582 softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588 CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G W 6.10.0-rc2-syzkaller-g8867bbd4a056 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Testing showed that the problem did not occur if the two error messages -- the first two lines above -- were removed; apparently adding material to the kernel log takes a surprisingly large amount of time. In any case, the best approach for preventing these lockups and to avoid spamming the log with thousands of error messages per second is to ratelimit the two dev_err() calls. Therefore we replace them with dev_err_ratelimited(). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Suggested-by: Greg KH <gregkh@linuxfoundation.org> Reported-and-tested-by: syzbot+5f996b83575ef4058638@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-usb/00000000000073d54b061a6a1c65@google.com/ Reported-and-tested-by: syzbot+1b2abad17596ad03dcff@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-usb/000000000000f45085061aa9b37e@google.com/ Fixes: 9908a32 ("USB: remove err() macro from usb class drivers") Link: https://lore.kernel.org/linux-usb/40dfa45b-5f21-4eef-a8c1-51a2f320e267@rowland.harvard.edu/ Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/29855215-52f5-4385-b058-91f42c2bee18@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ulrich Hecht <uli@kernel.org>

Move the loop-invariant calculation of 'cpu' in do_idle() out of the loop body, because the current CPU is always constant. This improves the generated code both on x86-64 and ARM64: x86-64: Before patch (execution in loop): 864: 0f ae e8 lfence 867: 65 8b 05 c2 38 f1 7e mov %gs:0x7ef138c2(%rip),%eax 86e: 89 c0 mov %eax,%eax 870: 48 0f a3 05 68 19 08 bt %rax,0x1081968(%rip) 877: 01 After patch (execution in loop): 872: 0f ae e8 lfence 875: 4c 0f a3 25 63 19 08 bt %r12,0x1081963(%rip) 87c: 01 ARM64: Before patch (execution in loop): c58: d5033d9f dsb ld c5c: d538d080 mrs x0, tpidr_el1 c60: b8606a61 ldr w1, [x19,x0] c64: 1100fc20 add w0, w1, #0x3f c68: 7100003f cmp w1, #0x0 c6c: 1a81b000 csel w0, w0, w1, lt c70: 13067c00 asr w0, w0, whatawurst#6 c74: 93407c00 sxtw x0, w0 c78: f8607a80 ldr x0, [x20,x0,lsl whatawurst#3] c7c: 9ac12401 lsr x1, x0, x1 c80: 36000581 tbz w1, #0, d30 <do_idle+0x128> After patch (execution in loop): c84: d5033d9f dsb ld c88: f9400260 ldr x0, [x19] c8c: ea14001f tst x0, x20 c90: 54000580 b.eq d40 <do_idle+0x138> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> [ Rewrote the title and the changelog. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: huawei.libin@huawei.com Cc: xiexiuqi@huawei.com Link: http://lkml.kernel.org/r/1508930907-107755-1-git-send-email-cj.chengjian@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>

Ashish Kumar Dhanotiya and others added 2 commits August 4, 2020 01:31

derfelot merged commit 6e21d7f into whatawurst:lineage-17.1 Aug 4, 2020

derfelot deleted the lineage-17.1_asb_2020-08 branch August 4, 2020 15:01

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[lineage-17.1] Android Security Bulletin 2020-08 #3

[lineage-17.1] Android Security Bulletin 2020-08 #3

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[lineage-17.1] Android Security Bulletin 2020-08 #3

[lineage-17.1] Android Security Bulletin 2020-08 #3

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