REFCOUNT #21

thestinger · 2017-05-11T18:31:12Z

This is in-progress as part of KSPP already. It would make sense to do some of this work here since they took an opt-in approach instead of opt-out. However, it's probably a good idea to focus on other things and keep an eye on it to avoid duplicating work.

commit 4dfce57 upstream. There have been several reports over the years of NULL pointer dereferences in xfs_trans_log_inode during xfs_fsr processes, when the process is doing an fput and tearing down extents on the temporary inode, something like: BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 PID: 29439 TASK: ffff880550584fa0 CPU: 6 COMMAND: "xfs_fsr" [exception RIP: xfs_trans_log_inode+0x10] #9 [ffff8800a57bbbe0] xfs_bunmapi at ffffffffa037398e [xfs] #10 [ffff8800a57bbce8] xfs_itruncate_extents at ffffffffa0391b29 [xfs] #11 [ffff8800a57bbd88] xfs_inactive_truncate at ffffffffa0391d0c [xfs] #12 [ffff8800a57bbdb8] xfs_inactive at ffffffffa0392508 [xfs] #13 [ffff8800a57bbdd8] xfs_fs_evict_inode at ffffffffa035907e [xfs] #14 [ffff8800a57bbe00] evict at ffffffff811e1b67 #15 [ffff8800a57bbe28] iput at ffffffff811e23a5 #16 [ffff8800a57bbe58] dentry_kill at ffffffff811dcfc8 #17 [ffff8800a57bbe88] dput at ffffffff811dd06c #18 [ffff8800a57bbea8] __fput at ffffffff811c823b #19 [ffff8800a57bbef0] ____fput at ffffffff811c846e #20 [ffff8800a57bbf00] task_work_run at ffffffff81093b27 #21 [ffff8800a57bbf30] do_notify_resume at ffffffff81013b0c #22 [ffff8800a57bbf50] int_signal at ffffffff8161405d As it turns out, this is because the i_itemp pointer, along with the d_ops pointer, has been overwritten with zeros when we tear down the extents during truncate. When the in-core inode fork on the temporary inode used by xfs_fsr was originally set up during the extent swap, we mistakenly looked at di_nextents to determine whether all extents fit inline, but this misses extents generated by speculative preallocation; we should be using if_bytes instead. This mistake corrupts the in-memory inode, and code in xfs_iext_remove_inline eventually gets bad inputs, causing it to memmove and memset incorrect ranges; this became apparent because the two values in ifp->if_u2.if_inline_ext[1] contained what should have been in d_ops and i_itemp; they were memmoved due to incorrect array indexing and then the original locations were zeroed with memset, again due to an array overrun. Fix this by properly using i_df.if_bytes to determine the number of extents, not di_nextents. Thanks to dchinner for looking at this with me and spotting the root cause. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 3998e6b upstream. When the final cifsFileInfo_put() is called from cifsiod and an oplock break work is queued, lockdep complains loudly: ============================================= [ INFO: possible recursive locking detected ] 4.11.0+ #21 Not tainted --------------------------------------------- kworker/0:2/78 is trying to acquire lock: ("cifsiod"){++++.+}, at: flush_work+0x215/0x350 but task is already holding lock: ("cifsiod"){++++.+}, at: process_one_work+0x255/0x8e0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock("cifsiod"); lock("cifsiod"); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by kworker/0:2/78: #0: ("cifsiod"){++++.+}, at: process_one_work+0x255/0x8e0 #1: ((&wdata->work)){+.+...}, at: process_one_work+0x255/0x8e0 stack backtrace: CPU: 0 PID: 78 Comm: kworker/0:2 Not tainted 4.11.0+ #21 Workqueue: cifsiod cifs_writev_complete Call Trace: dump_stack+0x85/0xc2 __lock_acquire+0x17dd/0x2260 ? match_held_lock+0x20/0x2b0 ? trace_hardirqs_off_caller+0x86/0x130 ? mark_lock+0xa6/0x920 lock_acquire+0xcc/0x260 ? lock_acquire+0xcc/0x260 ? flush_work+0x215/0x350 flush_work+0x236/0x350 ? flush_work+0x215/0x350 ? destroy_worker+0x170/0x170 __cancel_work_timer+0x17d/0x210 ? ___preempt_schedule+0x16/0x18 cancel_work_sync+0x10/0x20 cifsFileInfo_put+0x338/0x7f0 cifs_writedata_release+0x2a/0x40 ? cifs_writedata_release+0x2a/0x40 cifs_writev_complete+0x29d/0x850 ? preempt_count_sub+0x18/0xd0 process_one_work+0x304/0x8e0 worker_thread+0x9b/0x6a0 kthread+0x1b2/0x200 ? process_one_work+0x8e0/0x8e0 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x31/0x40 This is a real warning. Since the oplock is queued on the same workqueue this can deadlock if there is only one worker thread active for the workqueue (which will be the case during memory pressure when the rescuer thread is handling it). Furthermore, there is at least one other kind of hang possible due to the oplock break handling if there is only worker. (This can be reproduced without introducing memory pressure by having passing 1 for the max_active parameter of cifsiod.) cifs_oplock_break() can wait indefintely in the filemap_fdatawait() while the cifs_writev_complete() work is blocked: sysrq: SysRq : Show Blocked State task PC stack pid father kworker/0:1 D 0 16 2 0x00000000 Workqueue: cifsiod cifs_oplock_break Call Trace: __schedule+0x562/0xf40 ? mark_held_locks+0x4a/0xb0 schedule+0x57/0xe0 io_schedule+0x21/0x50 wait_on_page_bit+0x143/0x190 ? add_to_page_cache_lru+0x150/0x150 __filemap_fdatawait_range+0x134/0x190 ? do_writepages+0x51/0x70 filemap_fdatawait_range+0x14/0x30 filemap_fdatawait+0x3b/0x40 cifs_oplock_break+0x651/0x710 ? preempt_count_sub+0x18/0xd0 process_one_work+0x304/0x8e0 worker_thread+0x9b/0x6a0 kthread+0x1b2/0x200 ? process_one_work+0x8e0/0x8e0 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x31/0x40 dd D 0 683 171 0x00000000 Call Trace: __schedule+0x562/0xf40 ? mark_held_locks+0x29/0xb0 schedule+0x57/0xe0 io_schedule+0x21/0x50 wait_on_page_bit+0x143/0x190 ? add_to_page_cache_lru+0x150/0x150 __filemap_fdatawait_range+0x134/0x190 ? do_writepages+0x51/0x70 filemap_fdatawait_range+0x14/0x30 filemap_fdatawait+0x3b/0x40 filemap_write_and_wait+0x4e/0x70 cifs_flush+0x6a/0xb0 filp_close+0x52/0xa0 __close_fd+0xdc/0x150 SyS_close+0x33/0x60 entry_SYSCALL_64_fastpath+0x1f/0xbe Showing all locks held in the system: 2 locks held by kworker/0:1/16: #0: ("cifsiod"){.+.+.+}, at: process_one_work+0x255/0x8e0 #1: ((&cfile->oplock_break)){+.+.+.}, at: process_one_work+0x255/0x8e0 Showing busy workqueues and worker pools: workqueue cifsiod: flags=0xc pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1 in-flight: 16:cifs_oplock_break delayed: cifs_writev_complete, cifs_echo_request pool 0: cpus=0 node=0 flags=0x0 nice=0 hung=0s workers=3 idle: 750 3 Fix these problems by creating a a new workqueue (with a rescuer) for the oplock break work. Signed-off-by: Rabin Vincent <rabinv@axis.com> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 613bd1e upstream. Commit 9b61e30 (spi: Pick spi bus number from Linux idr or spi alias) ceased to unregister SPI buses with fixed bus numbers. Moreover this is visible only if CONFIG_SPI_DEBUG=y is set or when trying to re-register the same SPI controller. rmmod spi_pxa2xx_platform (with CONFIG_SPI_DEBUG=y): [ 26.788362] spi_master spi1: attempting to delete unregistered controller [spi1] modprobe spi_pxa2xx_platform: [ 37.883137] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:19.0/pxa2xx-spi.12/spi_master/spi1' [ 37.894984] CPU: 1 PID: 1467 Comm: modprobe Not tainted 4.16.0-rc4+ #21 [ 37.902384] Call Trace: ... [ 38.122680] kobject_add_internal failed for spi1 with -EEXIST, don't try to register things with the same name in the same directory. [ 38.136154] WARNING: CPU: 1 PID: 1467 at lib/kobject.c:238 kobject_add_internal+0x2a5/0x2f0 ... [ 38.513817] pxa2xx-spi pxa2xx-spi.12: problem registering spi master [ 38.521036] pxa2xx-spi: probe of pxa2xx-spi.12 failed with error -17 Fix this by not returning immediately from spi_unregister_controller() if idr_find() doesn't find controller with given ID/bus number. It finds only those controllers that were registered with dynamic SPI bus numbers. Only conditional cleanup between dynamic and fixed bus numbers is to remove allocated IDR. Fixes: 9b61e30 (spi: Pick spi bus number from Linux idr or spi alias) Cc: stable@vger.kernel.org Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit af50e4b ] syzbot caught an infinite recursion in nsh_gso_segment(). Problem here is that we need to make sure the NSH header is of reasonable length. BUG: MAX_LOCK_DEPTH too low! turning off the locking correctness validator. depth: 48 max: 48! 48 locks held by syz-executor0/10189: #0: (ptrval) (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x30f/0x34c0 net/core/dev.c:3517 #1: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #1: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #2: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #2: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #3: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #3: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #4: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #4: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #5: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #5: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #6: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #6: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #7: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #7: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #8: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #8: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #9: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #9: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #10: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #10: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #11: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #11: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #12: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #12: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #13: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #13: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #14: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #14: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #15: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #15: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #16: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #16: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #17: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #17: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #18: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #18: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #19: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #19: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #20: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #20: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #21: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #21: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #22: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #22: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #23: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #23: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #24: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #24: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #25: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #25: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #26: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #26: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #27: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #27: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #28: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #28: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #29: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #29: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #30: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #30: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #31: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #31: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 dccp_close: ABORT with 65423 bytes unread #32: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #32: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #33: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #33: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #34: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #34: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #35: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #35: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #36: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #36: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #37: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #37: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #38: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #38: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #39: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #39: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #40: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #40: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #41: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #41: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #42: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #42: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #43: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #43: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #44: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #44: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #45: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #45: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #46: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #46: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #47: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #47: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 INFO: lockdep is turned off. CPU: 1 PID: 10189 Comm: syz-executor0 Not tainted 4.17.0-rc2+ #26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 __lock_acquire+0x1788/0x5140 kernel/locking/lockdep.c:3449 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 rcu_lock_acquire include/linux/rcupdate.h:246 [inline] rcu_read_lock include/linux/rcupdate.h:632 [inline] skb_mac_gso_segment+0x25b/0x720 net/core/dev.c:2789 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 __skb_gso_segment+0x3bb/0x870 net/core/dev.c:2865 skb_gso_segment include/linux/netdevice.h:4025 [inline] validate_xmit_skb+0x54d/0xd90 net/core/dev.c:3118 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3168 sch_direct_xmit+0x354/0x11e0 net/sched/sch_generic.c:312 qdisc_restart net/sched/sch_generic.c:399 [inline] __qdisc_run+0x741/0x1af0 net/sched/sch_generic.c:410 __dev_xmit_skb net/core/dev.c:3243 [inline] __dev_queue_xmit+0x28ea/0x34c0 net/core/dev.c:3551 dev_queue_xmit+0x17/0x20 net/core/dev.c:3616 packet_snd net/packet/af_packet.c:2951 [inline] packet_sendmsg+0x40f8/0x6070 net/packet/af_packet.c:2976 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: c411ed8 ("nsh: add GSO support") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jiri Benc <jbenc@redhat.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 2bbea6e ] when mounting an ISO filesystem sometimes (very rarely) the system hangs because of a race condition between two tasks. PID: 6766 TASK: ffff88007b2a6dd0 CPU: 0 COMMAND: "mount" #0 [ffff880078447ae0] __schedule at ffffffff8168d605 #1 [ffff880078447b48] schedule_preempt_disabled at ffffffff8168ed49 #2 [ffff880078447b58] __mutex_lock_slowpath at ffffffff8168c995 #3 [ffff880078447bb8] mutex_lock at ffffffff8168bdef #4 [ffff880078447bd0] sr_block_ioctl at ffffffffa00b6818 [sr_mod] #5 [ffff880078447c10] blkdev_ioctl at ffffffff812fea50 #6 [ffff880078447c70] ioctl_by_bdev at ffffffff8123a8b3 #7 [ffff880078447c90] isofs_fill_super at ffffffffa04fb1e1 [isofs] #8 [ffff880078447da8] mount_bdev at ffffffff81202570 #9 [ffff880078447e18] isofs_mount at ffffffffa04f9828 [isofs] #10 [ffff880078447e28] mount_fs at ffffffff81202d09 #11 [ffff880078447e70] vfs_kern_mount at ffffffff8121ea8f #12 [ffff880078447ea8] do_mount at ffffffff81220fee #13 [ffff880078447f28] sys_mount at ffffffff812218d6 #14 [ffff880078447f80] system_call_fastpath at ffffffff81698c49 RIP: 00007fd9ea914e9a RSP: 00007ffd5d9bf648 RFLAGS: 00010246 RAX: 00000000000000a5 RBX: ffffffff81698c49 RCX: 0000000000000010 RDX: 00007fd9ec2bc210 RSI: 00007fd9ec2bc290 RDI: 00007fd9ec2bcf30 RBP: 0000000000000000 R8: 0000000000000000 R9: 0000000000000010 R10: 00000000c0ed0001 R11: 0000000000000206 R12: 00007fd9ec2bc040 R13: 00007fd9eb6b2380 R14: 00007fd9ec2bc210 R15: 00007fd9ec2bcf30 ORIG_RAX: 00000000000000a5 CS: 0033 SS: 002b This task was trying to mount the cdrom. It allocated and configured a super_block struct and owned the write-lock for the super_block->s_umount rwsem. While exclusively owning the s_umount lock, it called sr_block_ioctl and waited to acquire the global sr_mutex lock. PID: 6785 TASK: ffff880078720fb0 CPU: 0 COMMAND: "systemd-udevd" #0 [ffff880078417898] __schedule at ffffffff8168d605 #1 [ffff880078417900] schedule at ffffffff8168dc59 #2 [ffff880078417910] rwsem_down_read_failed at ffffffff8168f605 #3 [ffff880078417980] call_rwsem_down_read_failed at ffffffff81328838 #4 [ffff8800784179d0] down_read at ffffffff8168cde0 #5 [ffff8800784179e8] get_super at ffffffff81201cc7 #6 [ffff880078417a10] __invalidate_device at ffffffff8123a8de #7 [ffff880078417a40] flush_disk at ffffffff8123a94b #8 [ffff880078417a88] check_disk_change at ffffffff8123ab50 #9 [ffff880078417ab0] cdrom_open at ffffffffa00a29e1 [cdrom] #10 [ffff880078417b68] sr_block_open at ffffffffa00b6f9b [sr_mod] #11 [ffff880078417b98] __blkdev_get at ffffffff8123ba86 #12 [ffff880078417bf0] blkdev_get at ffffffff8123bd65 #13 [ffff880078417c78] blkdev_open at ffffffff8123bf9b #14 [ffff880078417c90] do_dentry_open at ffffffff811fc7f7 #15 [ffff880078417cd8] vfs_open at ffffffff811fc9cf #16 [ffff880078417d00] do_last at ffffffff8120d53d #17 [ffff880078417db0] path_openat at ffffffff8120e6b2 #18 [ffff880078417e48] do_filp_open at ffffffff8121082b #19 [ffff880078417f18] do_sys_open at ffffffff811fdd33 #20 [ffff880078417f70] sys_open at ffffffff811fde4e #21 [ffff880078417f80] system_call_fastpath at ffffffff81698c49 RIP: 00007f29438b0c20 RSP: 00007ffc76624b78 RFLAGS: 00010246 RAX: 0000000000000002 RBX: ffffffff81698c49 RCX: 0000000000000000 RDX: 00007f2944a5fa70 RSI: 00000000000a0800 RDI: 00007f2944a5fa70 RBP: 00007f2944a5f540 R8: 0000000000000000 R9: 0000000000000020 R10: 00007f2943614c40 R11: 0000000000000246 R12: ffffffff811fde4e R13: ffff880078417f78 R14: 000000000000000c R15: 00007f2944a4b010 ORIG_RAX: 0000000000000002 CS: 0033 SS: 002b This task tried to open the cdrom device, the sr_block_open function acquired the global sr_mutex lock. The call to check_disk_change() then saw an event flag indicating a possible media change and tried to flush any cached data for the device. As part of the flush, it tried to acquire the super_block->s_umount lock associated with the cdrom device. This was the same super_block as created and locked by the previous task. The first task acquires the s_umount lock and then the sr_mutex_lock; the second task acquires the sr_mutex_lock and then the s_umount lock. This patch fixes the issue by moving check_disk_change() out of cdrom_open() and let the caller take care of it. Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 36eb8ff upstream. Crash dump shows following instructions crash> bt PID: 0 TASK: ffffffffbe412480 CPU: 0 COMMAND: "swapper/0" #0 [ffff891ee0003868] machine_kexec at ffffffffbd063ef1 #1 [ffff891ee00038c8] __crash_kexec at ffffffffbd12b6f2 #2 [ffff891ee0003998] crash_kexec at ffffffffbd12c84c #3 [ffff891ee00039b8] oops_end at ffffffffbd030f0a #4 [ffff891ee00039e0] no_context at ffffffffbd074643 #5 [ffff891ee0003a40] __bad_area_nosemaphore at ffffffffbd07496e #6 [ffff891ee0003a90] bad_area_nosemaphore at ffffffffbd074a64 #7 [ffff891ee0003aa0] __do_page_fault at ffffffffbd074b0a #8 [ffff891ee0003b18] do_page_fault at ffffffffbd074fc8 #9 [ffff891ee0003b50] page_fault at ffffffffbda01925 [exception RIP: qlt_schedule_sess_for_deletion+15] RIP: ffffffffc02e526f RSP: ffff891ee0003c08 RFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffffc0307847 RDX: 00000000000020e6 RSI: ffff891edbc377c8 RDI: 0000000000000000 RBP: ffff891ee0003c18 R8: ffffffffc02f0b20 R9: 0000000000000250 R10: 0000000000000258 R11: 000000000000b780 R12: ffff891ed9b43000 R13: 00000000000000f0 R14: 0000000000000006 R15: ffff891edbc377c8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff891ee0003c20] qla2x00_fcport_event_handler at ffffffffc02853d3 [qla2xxx] #11 [ffff891ee0003cf0] __dta_qla24xx_async_gnl_sp_done_333 at ffffffffc0285a1d [qla2xxx] #12 [ffff891ee0003de8] qla24xx_process_response_queue at ffffffffc02a2eb5 [qla2xxx] #13 [ffff891ee0003e88] qla24xx_msix_rsp_q at ffffffffc02a5403 [qla2xxx] #14 [ffff891ee0003ec0] __handle_irq_event_percpu at ffffffffbd0f4c59 #15 [ffff891ee0003f10] handle_irq_event_percpu at ffffffffbd0f4e02 #16 [ffff891ee0003f40] handle_irq_event at ffffffffbd0f4e90 #17 [ffff891ee0003f68] handle_edge_irq at ffffffffbd0f8984 #18 [ffff891ee0003f88] handle_irq at ffffffffbd0305d5 #19 [ffff891ee0003fb8] do_IRQ at ffffffffbda02a18 --- <IRQ stack> --- #20 [ffffffffbe403d30] ret_from_intr at ffffffffbda0094e [exception RIP: unknown or invalid address] RIP: 000000000000001f RSP: 0000000000000000 RFLAGS: fff3b8c2091ebb3f RAX: ffffbba5a0000200 RBX: 0000be8cdfa8f9fa RCX: 0000000000000018 RDX: 0000000000000101 RSI: 000000000000015d RDI: 0000000000000193 RBP: 0000000000000083 R8: ffffffffbe403e38 R9: 0000000000000002 R10: 0000000000000000 R11: ffffffffbe56b820 R12: ffff891ee001cf00 R13: ffffffffbd11c0a4 R14: ffffffffbe403d60 R15: 0000000000000001 ORIG_RAX: ffff891ee0022ac0 CS: 0000 SS: ffffffffffffffb9 bt: WARNING: possibly bogus exception frame #21 [ffffffffbe403dd8] cpuidle_enter_state at ffffffffbd67c6fd #22 [ffffffffbe403e40] cpuidle_enter at ffffffffbd67c907 #23 [ffffffffbe403e50] call_cpuidle at ffffffffbd0d98f3 #24 [ffffffffbe403e60] do_idle at ffffffffbd0d9b42 #25 [ffffffffbe403e98] cpu_startup_entry at ffffffffbd0d9da3 #26 [ffffffffbe403ec0] rest_init at ffffffffbd81d4aa #27 [ffffffffbe403ed0] start_kernel at ffffffffbe67d2ca #28 [ffffffffbe403f28] x86_64_start_reservations at ffffffffbe67c675 #29 [ffffffffbe403f38] x86_64_start_kernel at ffffffffbe67c6eb #30 [ffffffffbe403f50] secondary_startup_64 at ffffffffbd0000d5 Fixes: 040036b ("scsi: qla2xxx: Delay loop id allocation at login") Cc: <stable@vger.kernel.org> # v4.17+ Signed-off-by: Chuck Anderson <chuck.anderson@oracle.com> Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit a5ba1d9 upstream. We have reports of the following crash: PID: 7 TASK: ffff88085c6d61c0 CPU: 1 COMMAND: "kworker/u25:0" #0 [ffff88085c6db710] machine_kexec at ffffffff81046239 #1 [ffff88085c6db760] crash_kexec at ffffffff810fc248 #2 [ffff88085c6db830] oops_end at ffffffff81008ae7 #3 [ffff88085c6db860] no_context at ffffffff81050b8f #4 [ffff88085c6db8b0] __bad_area_nosemaphore at ffffffff81050d75 #5 [ffff88085c6db900] bad_area_nosemaphore at ffffffff81050e83 #6 [ffff88085c6db910] __do_page_fault at ffffffff8105132e #7 [ffff88085c6db9b0] do_page_fault at ffffffff8105152c #8 [ffff88085c6db9c0] page_fault at ffffffff81a3f122 [exception RIP: uart_put_char+149] RIP: ffffffff814b67b5 RSP: ffff88085c6dba78 RFLAGS: 00010006 RAX: 0000000000000292 RBX: ffffffff827c5120 RCX: 0000000000000081 RDX: 0000000000000000 RSI: 000000000000005f RDI: ffffffff827c5120 RBP: ffff88085c6dba98 R8: 000000000000012c R9: ffffffff822ea320 R10: ffff88085fe4db04 R11: 0000000000000001 R12: ffff881059f9c000 R13: 0000000000000001 R14: 000000000000005f R15: 0000000000000fba ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #9 [ffff88085c6dbaa0] tty_put_char at ffffffff81497544 #10 [ffff88085c6dbac0] do_output_char at ffffffff8149c91c #11 [ffff88085c6dbae0] __process_echoes at ffffffff8149cb8b #12 [ffff88085c6dbb30] commit_echoes at ffffffff8149cdc2 #13 [ffff88085c6dbb60] n_tty_receive_buf_fast at ffffffff8149e49b #14 [ffff88085c6dbbc0] __receive_buf at ffffffff8149ef5a #15 [ffff88085c6dbc20] n_tty_receive_buf_common at ffffffff8149f016 #16 [ffff88085c6dbca0] n_tty_receive_buf2 at ffffffff8149f194 #17 [ffff88085c6dbcb0] flush_to_ldisc at ffffffff814a238a #18 [ffff88085c6dbd50] process_one_work at ffffffff81090be2 #19 [ffff88085c6dbe20] worker_thread at ffffffff81091b4d #20 [ffff88085c6dbeb0] kthread at ffffffff81096384 #21 [ffff88085c6dbf50] ret_from_fork at ffffffff81a3d69f after slogging through some dissasembly: ffffffff814b6720 <uart_put_char>: ffffffff814b6720: 55 push %rbp ffffffff814b6721: 48 89 e5 mov %rsp,%rbp ffffffff814b6724: 48 83 ec 20 sub $0x20,%rsp ffffffff814b6728: 48 89 1c 24 mov %rbx,(%rsp) ffffffff814b672c: 4c 89 64 24 08 mov %r12,0x8(%rsp) ffffffff814b6731: 4c 89 6c 24 10 mov %r13,0x10(%rsp) ffffffff814b6736: 4c 89 74 24 18 mov %r14,0x18(%rsp) ffffffff814b673b: e8 b0 8e 58 00 callq ffffffff81a3f5f0 <mcount> ffffffff814b6740: 4c 8b a7 88 02 00 00 mov 0x288(%rdi),%r12 ffffffff814b6747: 45 31 ed xor %r13d,%r13d ffffffff814b674a: 41 89 f6 mov %esi,%r14d ffffffff814b674d: 49 83 bc 24 70 01 00 cmpq $0x0,0x170(%r12) ffffffff814b6754: 00 00 ffffffff814b6756: 49 8b 9c 24 80 01 00 mov 0x180(%r12),%rbx ffffffff814b675d: 00 ffffffff814b675e: 74 2f je ffffffff814b678f <uart_put_char+0x6f> ffffffff814b6760: 48 89 df mov %rbx,%rdi ffffffff814b6763: e8 a8 67 58 00 callq ffffffff81a3cf10 <_raw_spin_lock_irqsave> ffffffff814b6768: 41 8b 8c 24 78 01 00 mov 0x178(%r12),%ecx ffffffff814b676f: 00 ffffffff814b6770: 89 ca mov %ecx,%edx ffffffff814b6772: f7 d2 not %edx ffffffff814b6774: 41 03 94 24 7c 01 00 add 0x17c(%r12),%edx ffffffff814b677b: 00 ffffffff814b677c: 81 e2 ff 0f 00 00 and $0xfff,%edx ffffffff814b6782: 75 23 jne ffffffff814b67a7 <uart_put_char+0x87> ffffffff814b6784: 48 89 c6 mov %rax,%rsi ffffffff814b6787: 48 89 df mov %rbx,%rdi ffffffff814b678a: e8 e1 64 58 00 callq ffffffff81a3cc70 <_raw_spin_unlock_irqrestore> ffffffff814b678f: 44 89 e8 mov %r13d,%eax ffffffff814b6792: 48 8b 1c 24 mov (%rsp),%rbx ffffffff814b6796: 4c 8b 64 24 08 mov 0x8(%rsp),%r12 ffffffff814b679b: 4c 8b 6c 24 10 mov 0x10(%rsp),%r13 ffffffff814b67a0: 4c 8b 74 24 18 mov 0x18(%rsp),%r14 ffffffff814b67a5: c9 leaveq ffffffff814b67a6: c3 retq ffffffff814b67a7: 49 8b 94 24 70 01 00 mov 0x170(%r12),%rdx ffffffff814b67ae: 00 ffffffff814b67af: 48 63 c9 movslq %ecx,%rcx ffffffff814b67b2: 41 b5 01 mov $0x1,%r13b ffffffff814b67b5: 44 88 34 0a mov %r14b,(%rdx,%rcx,1) ffffffff814b67b9: 41 8b 94 24 78 01 00 mov 0x178(%r12),%edx ffffffff814b67c0: 00 ffffffff814b67c1: 83 c2 01 add $0x1,%edx ffffffff814b67c4: 81 e2 ff 0f 00 00 and $0xfff,%edx ffffffff814b67ca: 41 89 94 24 78 01 00 mov %edx,0x178(%r12) ffffffff814b67d1: 00 ffffffff814b67d2: eb b0 jmp ffffffff814b6784 <uart_put_char+0x64> ffffffff814b67d4: 66 66 66 2e 0f 1f 84 data32 data32 nopw %cs:0x0(%rax,%rax,1) ffffffff814b67db: 00 00 00 00 00 for our build, this is crashing at: circ->buf[circ->head] = c; Looking in uart_port_startup(), it seems that circ->buf (state->xmit.buf) protected by the "per-port mutex", which based on uart_port_check() is state->port.mutex. Indeed, the lock acquired in uart_put_char() is uport->lock, i.e. not the same lock. Anyway, since the lock is not acquired, if uart_shutdown() is called, the last chunk of that function may release state->xmit.buf before its assigned to null, and cause the race above. To fix it, let's lock uport->lock when allocating/deallocating state->xmit.buf in addition to the per-port mutex. v2: switch to locking uport->lock on allocation/deallocation instead of locking the per-port mutex in uart_put_char. Note that since uport->lock is a spin lock, we have to switch the allocation to GFP_ATOMIC. v3: move the allocation outside the lock, so we can switch back to GFP_KERNEL Signed-off-by: Tycho Andersen <tycho@tycho.ws> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 8425843 ] pid_task() dereferences rcu protected tasks array. But there is no rcu_read_lock() in shutdown_umh() routine so that rcu_read_lock() is needed. get_pid_task() is wrapper function of pid_task. it holds rcu_read_lock() then calls pid_task(). if task isn't NULL, it increases reference count of task. test commands: %modprobe bpfilter %modprobe -rv bpfilter splat looks like: [15102.030932] ============================= [15102.030957] WARNING: suspicious RCU usage [15102.030985] 4.19.0-rc7+ #21 Not tainted [15102.031010] ----------------------------- [15102.031038] kernel/pid.c:330 suspicious rcu_dereference_check() usage! [15102.031063] other info that might help us debug this: [15102.031332] rcu_scheduler_active = 2, debug_locks = 1 [15102.031363] 1 lock held by modprobe/1570: [15102.031389] #0: 00000000580ef2b0 (bpfilter_lock){+.+.}, at: stop_umh+0x13/0x52 [bpfilter] [15102.031552] stack backtrace: [15102.031583] CPU: 1 PID: 1570 Comm: modprobe Not tainted 4.19.0-rc7+ #21 [15102.031607] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015 [15102.031628] Call Trace: [15102.031676] dump_stack+0xc9/0x16b [15102.031723] ? show_regs_print_info+0x5/0x5 [15102.031801] ? lockdep_rcu_suspicious+0x117/0x160 [15102.031855] pid_task+0x134/0x160 [15102.031900] ? find_vpid+0xf0/0xf0 [15102.032017] shutdown_umh.constprop.1+0x1e/0x53 [bpfilter] [15102.032055] stop_umh+0x46/0x52 [bpfilter] [15102.032092] __x64_sys_delete_module+0x47e/0x570 [ ... ] Fixes: d2ba09c ("net: add skeleton of bpfilter kernel module") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Increase kasan instrumented kernel stack size from 32k to 64k. Other architectures seems to get away with just doubling kernel stack size under kasan, but on s390 this appears to be not enough due to bigger frame size. The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting stack overflow is fs sync on xfs filesystem: #0 [9a0681e8] 704 bytes check_usage at 34b1fc GrapheneOS#1 [9a0684a8] 432 bytes check_usage at 34c710 GrapheneOS#2 [9a068658] 1048 bytes validate_chain at 35044a GrapheneOS#3 [9a068a70] 312 bytes __lock_acquire at 3559fe GrapheneOS#4 [9a068ba8] 440 bytes lock_acquire at 3576ee GrapheneOS#5 [9a068d60] 104 bytes _raw_spin_lock at 21b44e0 GrapheneOS#6 [9a068dc8] 1992 bytes enqueue_entity at 2dbf72 GrapheneOS#7 [9a069590] 1496 bytes enqueue_task_fair at 2df5f0 GrapheneOS#8 [9a069b68] 64 bytes ttwu_do_activate at 28f438 GrapheneOS#9 [9a069ba8] 552 bytes try_to_wake_up at 298c4c GrapheneOS#10 [9a069dd0] 168 bytes wake_up_worker at 23f97c GrapheneOS#11 [9a069e78] 200 bytes insert_work at 23fc2e GrapheneOS#12 [9a069f40] 648 bytes __queue_work at 2487c0 GrapheneOS#13 [9a06a1c8] 200 bytes __queue_delayed_work at 24db28 GrapheneOS#14 [9a06a290] 248 bytes mod_delayed_work_on at 24de84 GrapheneOS#15 [9a06a388] 24 bytes kblockd_mod_delayed_work_on at 153e2a0 GrapheneOS#16 [9a06a3a0] 288 bytes __blk_mq_delay_run_hw_queue at 158168c GrapheneOS#17 [9a06a4c0] 192 bytes blk_mq_run_hw_queue at 1581a3c GrapheneOS#18 [9a06a580] 184 bytes blk_mq_sched_insert_requests at 15a2192 GrapheneOS#19 [9a06a638] 1024 bytes blk_mq_flush_plug_list at 1590f3a GrapheneOS#20 [9a06aa38] 704 bytes blk_flush_plug_list at 1555028 GrapheneOS#21 [9a06acf8] 320 bytes schedule at 219e476 GrapheneOS#22 [9a06ae38] 760 bytes schedule_timeout at 21b0aac GrapheneOS#23 [9a06b130] 408 bytes wait_for_common at 21a1706 GrapheneOS#24 [9a06b2c8] 360 bytes xfs_buf_iowait at fa1540 GrapheneOS#25 [9a06b430] 256 bytes __xfs_buf_submit at fadae6 GrapheneOS#26 [9a06b530] 264 bytes xfs_buf_read_map at fae3f6 GrapheneOS#27 [9a06b638] 656 bytes xfs_trans_read_buf_map at 10ac9a8 GrapheneOS#28 [9a06b8c8] 304 bytes xfs_btree_kill_root at e72426 GrapheneOS#29 [9a06b9f8] 288 bytes xfs_btree_lookup_get_block at e7bc5e GrapheneOS#30 [9a06bb18] 624 bytes xfs_btree_lookup at e7e1a6 GrapheneOS#31 [9a06bd88] 2664 bytes xfs_alloc_ag_vextent_near at dfa070 GrapheneOS#32 [9a06c7f0] 144 bytes xfs_alloc_ag_vextent at dff3ca GrapheneOS#33 [9a06c880] 1128 bytes xfs_alloc_vextent at e05fce GrapheneOS#34 [9a06cce8] 584 bytes xfs_bmap_btalloc at e58342 GrapheneOS#35 [9a06cf30] 1336 bytes xfs_bmapi_write at e618de GrapheneOS#36 [9a06d468] 776 bytes xfs_iomap_write_allocate at ff678e GrapheneOS#37 [9a06d770] 720 bytes xfs_map_blocks at f82af8 GrapheneOS#38 [9a06da40] 928 bytes xfs_writepage_map at f83cd6 GrapheneOS#39 [9a06dde0] 320 bytes xfs_do_writepage at f85872 GrapheneOS#40 [9a06df20] 1320 bytes write_cache_pages at 73dfe8 GrapheneOS#41 [9a06e448] 208 bytes xfs_vm_writepages at f7f892 GrapheneOS#42 [9a06e518] 88 bytes do_writepages at 73fe6a GrapheneOS#43 [9a06e570] 872 bytes __writeback_single_inode at a20cb6 GrapheneOS#44 [9a06e8d8] 664 bytes writeback_sb_inodes at a23be2 GrapheneOS#45 [9a06eb70] 296 bytes __writeback_inodes_wb at a242e0 GrapheneOS#46 [9a06ec98] 928 bytes wb_writeback at a2500e GrapheneOS#47 [9a06f038] 848 bytes wb_do_writeback at a260ae GrapheneOS#48 [9a06f388] 536 bytes wb_workfn at a28228 GrapheneOS#49 [9a06f5a0] 1088 bytes process_one_work at 24a234 GrapheneOS#50 [9a06f9e0] 1120 bytes worker_thread at 24ba26 GrapheneOS#51 [9a06fe40] 104 bytes kthread at 26545a GrapheneOS#52 [9a06fea8] kernel_thread_starter at 21b6b62 To be able to increase the stack size to 64k reuse LLILL instruction in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE (65192) value as unsigned. Reported-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

xt_rateest_net_exit() was added to check whether rules are flushed successfully. but ->net_exit() callback is called earlier than ->destroy() callback. So that ->net_exit() callback can't check that. test commands: %ip netns add vm1 %ip netns exec vm1 iptables -t mangle -I PREROUTING -p udp \ --dport 1111 -j RATEEST --rateest-name ap \ --rateest-interval 250ms --rateest-ewma 0.5s %ip netns del vm1 splat looks like: [ 668.813518] WARNING: CPU: 0 PID: 87 at net/netfilter/xt_RATEEST.c:210 xt_rateest_net_exit+0x210/0x340 [xt_RATEEST] [ 668.813518] Modules linked in: xt_RATEEST xt_tcpudp iptable_mangle bpfilter ip_tables x_tables [ 668.813518] CPU: 0 PID: 87 Comm: kworker/u4:2 Not tainted 4.19.0-rc7+ GrapheneOS#21 [ 668.813518] Workqueue: netns cleanup_net [ 668.813518] RIP: 0010:xt_rateest_net_exit+0x210/0x340 [xt_RATEEST] [ 668.813518] Code: 00 48 8b 85 30 ff ff ff 4c 8b 23 80 38 00 0f 85 24 01 00 00 48 8b 85 30 ff ff ff 4d 85 e4 4c 89 a5 58 ff ff ff c6 00 f8 74 b2 <0f> 0b 48 83 c3 08 4c 39 f3 75 b0 48 b8 00 00 00 00 00 fc ff df 49 [ 668.813518] RSP: 0018:ffff8801156c73f8 EFLAGS: 00010282 [ 668.813518] RAX: ffffed0022ad8e85 RBX: ffff880118928e98 RCX: 5db8012a00000000 [ 668.813518] RDX: ffff8801156c7428 RSI: 00000000cb1d185f RDI: ffff880115663b74 [ 668.813518] RBP: ffff8801156c74d0 R08: ffff8801156633c0 R09: 1ffff100236440be [ 668.813518] R10: 0000000000000001 R11: ffffed002367d852 R12: ffff880115142b08 [ 668.813518] R13: 1ffff10022ad8e81 R14: ffff880118928ea8 R15: dffffc0000000000 [ 668.813518] FS: 0000000000000000(0000) GS:ffff88011b200000(0000) knlGS:0000000000000000 [ 668.813518] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 668.813518] CR2: 0000563aa69f4f28 CR3: 0000000105a16000 CR4: 00000000001006f0 [ 668.813518] Call Trace: [ 668.813518] ? unregister_netdevice_many+0xe0/0xe0 [ 668.813518] ? xt_rateest_net_init+0x2c0/0x2c0 [xt_RATEEST] [ 668.813518] ? default_device_exit+0x1ca/0x270 [ 668.813518] ? remove_proc_entry+0x1cd/0x390 [ 668.813518] ? dev_change_net_namespace+0xd00/0xd00 [ 668.813518] ? __init_waitqueue_head+0x130/0x130 [ 668.813518] ops_exit_list.isra.10+0x94/0x140 [ 668.813518] cleanup_net+0x45b/0x900 [ 668.813518] ? net_drop_ns+0x110/0x110 [ 668.813518] ? swapgs_restore_regs_and_return_to_usermode+0x3c/0x80 [ 668.813518] ? save_trace+0x300/0x300 [ 668.813518] ? lock_acquire+0x196/0x470 [ 668.813518] ? lock_acquire+0x196/0x470 [ 668.813518] ? process_one_work+0xb60/0x1de0 [ 668.813518] ? _raw_spin_unlock_irq+0x29/0x40 [ 668.813518] ? _raw_spin_unlock_irq+0x29/0x40 [ 668.813518] ? __lock_acquire+0x4500/0x4500 [ 668.813518] ? __lock_is_held+0xb4/0x140 [ 668.813518] process_one_work+0xc13/0x1de0 [ 668.813518] ? pwq_dec_nr_in_flight+0x3c0/0x3c0 [ 668.813518] ? set_load_weight+0x270/0x270 [ ... ] Fixes: 3427b2a ("netfilter: make xt_rateest hash table per net") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

[ Upstream commit 0fbcc5b ] xt_rateest_net_exit() was added to check whether rules are flushed successfully. but ->net_exit() callback is called earlier than ->destroy() callback. So that ->net_exit() callback can't check that. test commands: %ip netns add vm1 %ip netns exec vm1 iptables -t mangle -I PREROUTING -p udp \ --dport 1111 -j RATEEST --rateest-name ap \ --rateest-interval 250ms --rateest-ewma 0.5s %ip netns del vm1 splat looks like: [ 668.813518] WARNING: CPU: 0 PID: 87 at net/netfilter/xt_RATEEST.c:210 xt_rateest_net_exit+0x210/0x340 [xt_RATEEST] [ 668.813518] Modules linked in: xt_RATEEST xt_tcpudp iptable_mangle bpfilter ip_tables x_tables [ 668.813518] CPU: 0 PID: 87 Comm: kworker/u4:2 Not tainted 4.19.0-rc7+ #21 [ 668.813518] Workqueue: netns cleanup_net [ 668.813518] RIP: 0010:xt_rateest_net_exit+0x210/0x340 [xt_RATEEST] [ 668.813518] Code: 00 48 8b 85 30 ff ff ff 4c 8b 23 80 38 00 0f 85 24 01 00 00 48 8b 85 30 ff ff ff 4d 85 e4 4c 89 a5 58 ff ff ff c6 00 f8 74 b2 <0f> 0b 48 83 c3 08 4c 39 f3 75 b0 48 b8 00 00 00 00 00 fc ff df 49 [ 668.813518] RSP: 0018:ffff8801156c73f8 EFLAGS: 00010282 [ 668.813518] RAX: ffffed0022ad8e85 RBX: ffff880118928e98 RCX: 5db8012a00000000 [ 668.813518] RDX: ffff8801156c7428 RSI: 00000000cb1d185f RDI: ffff880115663b74 [ 668.813518] RBP: ffff8801156c74d0 R08: ffff8801156633c0 R09: 1ffff100236440be [ 668.813518] R10: 0000000000000001 R11: ffffed002367d852 R12: ffff880115142b08 [ 668.813518] R13: 1ffff10022ad8e81 R14: ffff880118928ea8 R15: dffffc0000000000 [ 668.813518] FS: 0000000000000000(0000) GS:ffff88011b200000(0000) knlGS:0000000000000000 [ 668.813518] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 668.813518] CR2: 0000563aa69f4f28 CR3: 0000000105a16000 CR4: 00000000001006f0 [ 668.813518] Call Trace: [ 668.813518] ? unregister_netdevice_many+0xe0/0xe0 [ 668.813518] ? xt_rateest_net_init+0x2c0/0x2c0 [xt_RATEEST] [ 668.813518] ? default_device_exit+0x1ca/0x270 [ 668.813518] ? remove_proc_entry+0x1cd/0x390 [ 668.813518] ? dev_change_net_namespace+0xd00/0xd00 [ 668.813518] ? __init_waitqueue_head+0x130/0x130 [ 668.813518] ops_exit_list.isra.10+0x94/0x140 [ 668.813518] cleanup_net+0x45b/0x900 [ 668.813518] ? net_drop_ns+0x110/0x110 [ 668.813518] ? swapgs_restore_regs_and_return_to_usermode+0x3c/0x80 [ 668.813518] ? save_trace+0x300/0x300 [ 668.813518] ? lock_acquire+0x196/0x470 [ 668.813518] ? lock_acquire+0x196/0x470 [ 668.813518] ? process_one_work+0xb60/0x1de0 [ 668.813518] ? _raw_spin_unlock_irq+0x29/0x40 [ 668.813518] ? _raw_spin_unlock_irq+0x29/0x40 [ 668.813518] ? __lock_acquire+0x4500/0x4500 [ 668.813518] ? __lock_is_held+0xb4/0x140 [ 668.813518] process_one_work+0xc13/0x1de0 [ 668.813518] ? pwq_dec_nr_in_flight+0x3c0/0x3c0 [ 668.813518] ? set_load_weight+0x270/0x270 [ ... ] Fixes: 3427b2a ("netfilter: make xt_rateest hash table per net") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

A bug is present in GDB which causes early string termination when parsing variables. This has been reported [0], but we should ensure that we can support at least basic printing of the core kernel strings. For current gdb version (has been tested with 7.3 and 8.1), 'lx-version' only prints one character. (gdb) lx-version L(gdb) This can be fixed by casting 'linux_banner' as (char *). (gdb) lx-version Linux version 4.19.0-rc1+ (changbin@acer) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) GrapheneOS#21 SMP Sat Sep 1 21:43:30 CST 2018 [0] https://sourceware.org/bugzilla/show_bug.cgi?id=20077 [kbingham@kernel.org: add detail to commit message] Link: http://lkml.kernel.org/r/20181111162035.8356-1-kieran.bingham@ideasonboard.com Fixes: 2d061d9 ("scripts/gdb: add version command") Signed-off-by: Du Changbin <changbin.du@gmail.com> Signed-off-by: Kieran Bingham <kbingham@kernel.org> Acked-by: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[ Upstream commit 85744e9 ] A bad job is the one triggered TDR(In the current amdgpu's implementation, actually all the jobs in the current joq-queue will be treated as bad jobs). In the recovery process, its fence will be fake signaled and as a result, the work behind will be scheduled to delete it from the mirror list, but if the TDR process is invoked before the work's execution, then this bad job might be processed again and the call dma_fence_set_error to its fence in TDR process will lead to kernel warning trace: [ 143.033605] WARNING: CPU: 2 PID: 53 at ./include/linux/dma-fence.h:437 amddrm_sched_job_recovery+0x1af/0x1c0 [amd_sched] kernel: [ 143.033606] Modules linked in: amdgpu(OE) amdchash(OE) amdttm(OE) amd_sched(OE) amdkcl(OE) amd_iommu_v2 drm_kms_helper drm i2c_algo_bit fb_sys_fops syscopyarea sysfillrect sysimgblt kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel aes_x86_64 snd_hda_codec_generic crypto_simd glue_helper cryptd snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq joydev snd_seq_device snd_timer snd soundcore binfmt_misc input_leds mac_hid serio_raw nfsd auth_rpcgss nfs_acl lockd grace sunrpc sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 8139too floppy psmouse 8139cp mii i2c_piix4 pata_acpi [ 143.033649] CPU: 2 PID: 53 Comm: kworker/2:1 Tainted: G OE 4.15.0-20-generic #21-Ubuntu [ 143.033650] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 [ 143.033653] Workqueue: events drm_sched_job_timedout [amd_sched] [ 143.033656] RIP: 0010:amddrm_sched_job_recovery+0x1af/0x1c0 [amd_sched] [ 143.033657] RSP: 0018:ffffa9f880fe7d48 EFLAGS: 00010202 [ 143.033659] RAX: 0000000000000007 RBX: ffff9b98f2b24c00 RCX: ffff9b98efef4f08 [ 143.033660] RDX: ffff9b98f2b27400 RSI: ffff9b98f2b24c50 RDI: ffff9b98efef4f18 [ 143.033660] RBP: ffffa9f880fe7d98 R08: 0000000000000001 R09: 00000000000002b6 [ 143.033661] R10: 0000000000000000 R11: 0000000000000000 R12: ffff9b98efef3430 [ 143.033662] R13: ffff9b98efef4d80 R14: ffff9b98efef4e98 R15: ffff9b98eaf91c00 [ 143.033663] FS: 0000000000000000(0000) GS:ffff9b98ffd00000(0000) knlGS:0000000000000000 [ 143.033664] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 143.033665] CR2: 00007fc49c96d470 CR3: 000000001400a005 CR4: 00000000003606e0 [ 143.033669] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 143.033669] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 143.033670] Call Trace: [ 143.033744] amdgpu_device_gpu_recover+0x144/0x820 [amdgpu] [ 143.033788] amdgpu_job_timedout+0x9b/0xa0 [amdgpu] [ 143.033791] drm_sched_job_timedout+0xcc/0x150 [amd_sched] [ 143.033795] process_one_work+0x1de/0x410 [ 143.033797] worker_thread+0x32/0x410 [ 143.033799] kthread+0x121/0x140 [ 143.033801] ? process_one_work+0x410/0x410 [ 143.033803] ? kthread_create_worker_on_cpu+0x70/0x70 [ 143.033806] ret_from_fork+0x35/0x40 So just delete the bad job from mirror list directly Changes in v3: - Add a helper function to delete the bad jobs from mirror list and call it directly *before* the job's fence is signaled Changes in v2: - delete the useless list node check - also delete bad jobs in drm_sched_main because: kthread_unpark(ring->sched.thread) will be invoked very early before amdgpu_device_gpu_recover's return, then drm_sched_main will have chance to pick up a new job from the job queue. This new job will be added into the mirror list and processed by amdgpu_job_run, but may not be deleted from the mirror list on time due to the same reason. And finally re-processed by drm_sched_job_recovery Signed-off-by: Trigger Huang <Trigger.Huang@amd.com> Reviewed-by: Christian König <chrstian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit b058809 ] A bug is present in GDB which causes early string termination when parsing variables. This has been reported [0], but we should ensure that we can support at least basic printing of the core kernel strings. For current gdb version (has been tested with 7.3 and 8.1), 'lx-version' only prints one character. (gdb) lx-version L(gdb) This can be fixed by casting 'linux_banner' as (char *). (gdb) lx-version Linux version 4.19.0-rc1+ (changbin@acer) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #21 SMP Sat Sep 1 21:43:30 CST 2018 [0] https://sourceware.org/bugzilla/show_bug.cgi?id=20077 [kbingham@kernel.org: add detail to commit message] Link: http://lkml.kernel.org/r/20181111162035.8356-1-kieran.bingham@ideasonboard.com Fixes: 2d061d9 ("scripts/gdb: add version command") Signed-off-by: Du Changbin <changbin.du@gmail.com> Signed-off-by: Kieran Bingham <kbingham@kernel.org> Acked-by: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

Eric has reported on OpenWrt's bug tracking system[1], that he's not able to use USB devices on his WNDR3400v2 device after the boot, until he turns on GPIO GrapheneOS#21 manually through sysfs. 1. https://bugs.openwrt.org/index.php?do=details&task_id=2170 Cc: Rafał Miłecki <zajec5@gmail.com> Cc: Hauke Mehrtens <hauke@hauke-m.de> Reported-by: Eric Bohlman <ericbohlman@gmail.com> Tested-by: Eric Bohlman <ericbohlman@gmail.com> Signed-off-by: Petr Štetiar <ynezz@true.cz> Signed-off-by: Paul Burton <paul.burton@mips.com>

[ Upstream commit 30f3312 ] ttm_bo_glob and ttm_mem_glob are defined as structure instance, while not allocated by kzalloc, so kfree should not be invoked to release them anymore. Otherwise, it will cause the following kernel BUG when unloading amdgpu module [ 48.419294] kernel BUG at /build/linux-5s7Xkn/linux-4.15.0/mm/slub.c:3894! [ 48.419352] invalid opcode: 0000 [#1] SMP PTI [ 48.419387] Modules linked in: amdgpu(OE-) amdchash(OE) amdttm(OE) amd_sched(OE) amdkcl(OE) amd_iommu_v2 drm_kms_helper drm i2c_algo_bit fb_sys_fops syscopyarea sysfillrect sysimgblt snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi pcbc snd_seq snd_seq_device snd_timer aesni_intel snd soundcore joydev aes_x86_64 crypto_simd glue_helper cryptd input_leds mac_hid serio_raw binfmt_misc nfsd auth_rpcgss nfs_acl lockd grace sunrpc sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 8139too psmouse i2c_piix4 8139cp mii floppy pata_acpi [ 48.419782] CPU: 1 PID: 1281 Comm: modprobe Tainted: G OE 4.15.0-20-generic #21-Ubuntu [ 48.419838] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 [ 48.419901] RIP: 0010:kfree+0x137/0x180 [ 48.419934] RSP: 0018:ffffb02101273bf8 EFLAGS: 00010246 [ 48.419974] RAX: ffffeee1418ad7e0 RBX: ffffffffc075f100 RCX: ffff8fed7fca7ed0 [ 48.420025] RDX: 0000000000000000 RSI: 000000000003440e RDI: 0000000022400000 [ 48.420073] RBP: ffffb02101273c10 R08: 0000000000000010 R09: ffff8fed7ffd3680 [ 48.420121] R10: ffffeee1418ad7c0 R11: ffff8fed7ffd3000 R12: ffffffffc075e2c0 [ 48.420169] R13: ffffffffc074ec10 R14: ffff8fed73063900 R15: ffff8fed737428e8 [ 48.420216] FS: 00007fdc912ec540(0000) GS:ffff8fed7fc80000(0000) knlGS:0000000000000000 [ 48.420267] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 48.420308] CR2: 000055fa40c30060 CR3: 000000023470a006 CR4: 00000000003606e0 [ 48.420358] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 48.420405] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 48.420452] Call Trace: [ 48.420485] ttm_bo_global_kobj_release+0x20/0x30 [amdttm] [ 48.420528] kobject_release+0x6a/0x180 [ 48.420562] kobject_put+0x28/0x50 [ 48.420595] ttm_bo_global_release+0x36/0x50 [amdttm] [ 48.420636] amdttm_bo_device_release+0x119/0x180 [amdttm] [ 48.420678] ? amdttm_bo_clean_mm+0xa6/0xf0 [amdttm] [ 48.420760] amdgpu_ttm_fini+0xc9/0x180 [amdgpu] [ 48.420821] amdgpu_bo_fini+0x12/0x40 [amdgpu] [ 48.420889] gmc_v9_0_sw_fini+0x40/0x50 [amdgpu] [ 48.420947] amdgpu_device_fini+0x36f/0x4c0 [amdgpu] [ 48.421007] amdgpu_driver_unload_kms+0xb4/0x150 [amdgpu] [ 48.421058] drm_dev_unregister+0x46/0xf0 [drm] [ 48.421102] drm_dev_unplug+0x12/0x70 [drm] Signed-off-by: Trigger Huang <Trigger.Huang@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

af_inet sets sock->sk to NULL which trips strparser over: BUG: kernel NULL pointer dereference, address: 0000000000000012 PGD 0 P4D 0 Oops: 0000 [GrapheneOS#1] SMP PTI CPU: 7 PID: 0 Comm: swapper/7 Not tainted 5.2.0-rc1-00139-g14629453a6d3 GrapheneOS#21 RIP: 0010:tcp_peek_len+0x10/0x60 RSP: 0018:ffffc02e41c54b98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff9cf924c4e030 RCX: 0000000000000051 RDX: 0000000000000000 RSI: 000000000000000c RDI: ffff9cf97128f480 RBP: ffff9cf9365e0300 R08: ffff9cf94fe7d2c0 R09: 0000000000000000 R10: 000000000000036b R11: ffff9cf939735e00 R12: ffff9cf91ad9ae40 R13: ffff9cf924c4e000 R14: ffff9cf9a8fcbaae R15: 0000000000000020 FS: 0000000000000000(0000) GS:ffff9cf9af7c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000012 CR3: 000000013920a003 CR4: 00000000003606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> strp_data_ready+0x48/0x90 tls_data_ready+0x22/0xd0 [tls] tcp_rcv_established+0x569/0x620 tcp_v4_do_rcv+0x127/0x1e0 tcp_v4_rcv+0xad7/0xbf0 ip_protocol_deliver_rcu+0x2c/0x1c0 ip_local_deliver_finish+0x41/0x50 ip_local_deliver+0x6b/0xe0 ? ip_protocol_deliver_rcu+0x1c0/0x1c0 ip_rcv+0x52/0xd0 ? ip_rcv_finish_core.isra.20+0x380/0x380 __netif_receive_skb_one_core+0x7e/0x90 netif_receive_skb_internal+0x42/0xf0 napi_gro_receive+0xed/0x150 nfp_net_poll+0x7a2/0xd30 [nfp] ? kmem_cache_free_bulk+0x286/0x310 net_rx_action+0x149/0x3b0 __do_softirq+0xe3/0x30a ? handle_irq_event_percpu+0x6a/0x80 irq_exit+0xe8/0xf0 do_IRQ+0x85/0xd0 common_interrupt+0xf/0xf </IRQ> RIP: 0010:cpuidle_enter_state+0xbc/0x450 To avoid this issue set sock->sk after sk_prot->close. My grepping and testing did not discover any code which would depend on the current behaviour. Fixes: c46234e ("tls: RX path for ktls") Reported-by: David Beckett <david.beckett@netronome.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>

[ Upstream commit 2542604 ] When a matchall classifier is added, there is a small time interval in which tp->root is NULL. If we receive a packet in this small time slice a NULL pointer dereference will happen, leading to a kernel panic: # tc qdisc replace dev eth0 ingress # tc filter add dev eth0 parent ffff: matchall action gact drop Unable to handle kernel NULL pointer dereference at virtual address 0000000000000034 Mem abort info: ESR = 0x96000005 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000005 CM = 0, WnR = 0 user pgtable: 4k pages, 39-bit VAs, pgdp = 00000000a623d530 [0000000000000034] pgd=0000000000000000, pud=0000000000000000 Internal error: Oops: 96000005 [#1] SMP Modules linked in: cls_matchall sch_ingress nls_iso8859_1 nls_cp437 vfat fat m25p80 spi_nor mtd xhci_plat_hcd xhci_hcd phy_generic sfp mdio_i2c usbcore i2c_mv64xxx marvell10g mvpp2 usb_common spi_orion mvmdio i2c_core sbsa_gwdt phylink ip_tables x_tables autofs4 Process ksoftirqd/0 (pid: 9, stack limit = 0x0000000009de7d62) CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.1.0-rc6 #21 Hardware name: Marvell 8040 MACCHIATOBin Double-shot (DT) pstate: 40000005 (nZcv daif -PAN -UAO) pc : mall_classify+0x28/0x78 [cls_matchall] lr : tcf_classify+0x78/0x138 sp : ffffff80109db9d0 x29: ffffff80109db9d0 x28: ffffffc426058800 x27: 0000000000000000 x26: ffffffc425b0dd00 x25: 0000000020000000 x24: 0000000000000000 x23: ffffff80109dbac0 x22: 0000000000000001 x21: ffffffc428ab5100 x20: ffffffc425b0dd00 x19: ffffff80109dbac0 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: ffffffbf108ad288 x12: dead000000000200 x11: 00000000f0000000 x10: 0000000000000001 x9 : ffffffbf1089a220 x8 : 0000000000000001 x7 : ffffffbebffaa950 x6 : 0000000000000000 x5 : 000000442d6ba000 x4 : 0000000000000000 x3 : ffffff8008735ad8 x2 : ffffff80109dbac0 x1 : ffffffc425b0dd00 x0 : ffffff8010592078 Call trace: mall_classify+0x28/0x78 [cls_matchall] tcf_classify+0x78/0x138 __netif_receive_skb_core+0x29c/0xa20 __netif_receive_skb_one_core+0x34/0x60 __netif_receive_skb+0x28/0x78 netif_receive_skb_internal+0x2c/0xc0 napi_gro_receive+0x1a0/0x1d8 mvpp2_poll+0x928/0xb18 [mvpp2] net_rx_action+0x108/0x378 __do_softirq+0x128/0x320 run_ksoftirqd+0x44/0x60 smpboot_thread_fn+0x168/0x1b0 kthread+0x12c/0x130 ret_from_fork+0x10/0x1c Code: aa0203f3 aa1e03e0 d503201f f9400684 (b9403480) ---[ end trace fc71e2ef7b8ab5a5 ]--- Kernel panic - not syncing: Fatal exception in interrupt SMP: stopping secondary CPUs Kernel Offset: disabled CPU features: 0x002,00002000 Memory Limit: none Rebooting in 1 seconds.. Fix this by adding a NULL check in mall_classify(). Fixes: ed76f5e ("net: sched: protect filter_chain list with filter_chain_lock mutex") Signed-off-by: Matteo Croce <mcroce@redhat.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit d0a255e upstream. A deadlock with this stacktrace was observed. The loop thread does a GFP_KERNEL allocation, it calls into dm-bufio shrinker and the shrinker depends on I/O completion in the dm-bufio subsystem. In order to fix the deadlock (and other similar ones), we set the flag PF_MEMALLOC_NOIO at loop thread entry. PID: 474 TASK: ffff8813e11f4600 CPU: 10 COMMAND: "kswapd0" #0 [ffff8813dedfb938] __schedule at ffffffff8173f405 #1 [ffff8813dedfb990] schedule at ffffffff8173fa27 #2 [ffff8813dedfb9b0] schedule_timeout at ffffffff81742fec #3 [ffff8813dedfba60] io_schedule_timeout at ffffffff8173f186 #4 [ffff8813dedfbaa0] bit_wait_io at ffffffff8174034f #5 [ffff8813dedfbac0] __wait_on_bit at ffffffff8173fec8 #6 [ffff8813dedfbb10] out_of_line_wait_on_bit at ffffffff8173ff81 #7 [ffff8813dedfbb90] __make_buffer_clean at ffffffffa038736f [dm_bufio] #8 [ffff8813dedfbbb0] __try_evict_buffer at ffffffffa0387bb8 [dm_bufio] #9 [ffff8813dedfbbd0] dm_bufio_shrink_scan at ffffffffa0387cc3 [dm_bufio] #10 [ffff8813dedfbc40] shrink_slab at ffffffff811a87ce #11 [ffff8813dedfbd30] shrink_zone at ffffffff811ad778 #12 [ffff8813dedfbdc0] kswapd at ffffffff811ae92f #13 [ffff8813dedfbec0] kthread at ffffffff810a8428 #14 [ffff8813dedfbf50] ret_from_fork at ffffffff81745242 PID: 14127 TASK: ffff881455749c00 CPU: 11 COMMAND: "loop1" #0 [ffff88272f5af228] __schedule at ffffffff8173f405 #1 [ffff88272f5af280] schedule at ffffffff8173fa27 #2 [ffff88272f5af2a0] schedule_preempt_disabled at ffffffff8173fd5e #3 [ffff88272f5af2b0] __mutex_lock_slowpath at ffffffff81741fb5 #4 [ffff88272f5af330] mutex_lock at ffffffff81742133 #5 [ffff88272f5af350] dm_bufio_shrink_count at ffffffffa03865f9 [dm_bufio] #6 [ffff88272f5af380] shrink_slab at ffffffff811a86bd #7 [ffff88272f5af470] shrink_zone at ffffffff811ad778 #8 [ffff88272f5af500] do_try_to_free_pages at ffffffff811adb34 #9 [ffff88272f5af590] try_to_free_pages at ffffffff811adef8 #10 [ffff88272f5af610] __alloc_pages_nodemask at ffffffff811a09c3 #11 [ffff88272f5af710] alloc_pages_current at ffffffff811e8b71 #12 [ffff88272f5af760] new_slab at ffffffff811f4523 #13 [ffff88272f5af7b0] __slab_alloc at ffffffff8173a1b5 #14 [ffff88272f5af880] kmem_cache_alloc at ffffffff811f484b #15 [ffff88272f5af8d0] do_blockdev_direct_IO at ffffffff812535b3 #16 [ffff88272f5afb00] __blockdev_direct_IO at ffffffff81255dc3 #17 [ffff88272f5afb30] xfs_vm_direct_IO at ffffffffa01fe3fc [xfs] #18 [ffff88272f5afb90] generic_file_read_iter at ffffffff81198994 #19 [ffff88272f5afc50] __dta_xfs_file_read_iter_2398 at ffffffffa020c970 [xfs] #20 [ffff88272f5afcc0] lo_rw_aio at ffffffffa0377042 [loop] #21 [ffff88272f5afd70] loop_queue_work at ffffffffa0377c3b [loop] #22 [ffff88272f5afe60] kthread_worker_fn at ffffffff810a8a0c #23 [ffff88272f5afec0] kthread at ffffffff810a8428 #24 [ffff88272f5aff50] ret_from_fork at ffffffff81745242 Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thestinger added the type-enhancement label May 11, 2017

thestinger added PaX priority-low status-in-progress-elsewhere and removed priority-low labels May 15, 2017

thestinger closed this as completed Nov 22, 2017

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REFCOUNT #21

REFCOUNT #21

thestinger commented May 11, 2017 •

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REFCOUNT #21

REFCOUNT #21

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thestinger commented May 11, 2017 • edited Loading

thestinger commented May 11, 2017 •

edited

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