syzbot


BUG: sleeping function called from invalid context in tpk_write

Status: fixed on 2020/02/18 14:31
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+2eeef62ee31f9460ad65@syzkaller.appspotmail.com
Fix commit: 9a655c77ff8f ttyprintk: fix a potential deadlock in interrupt context issue
First crash: 1623d, last: 1582d
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: no output from test machine (log)
Repro: C syz .config
  
Discussions (10)
Title Replies (including bot) Last reply
[PATCH 5.5 00/23] 5.5.2-stable review 31 (31) 2020/02/08 16:13
[PATCH 4.4 00/53] 4.4.213-stable review 63 (63) 2020/02/05 22:37
[PATCH 5.4 00/90] 5.4.18-stable review 107 (107) 2020/02/05 21:21
[PATCH 4.19 00/70] 4.19.102-stable review 77 (77) 2020/02/05 14:42
[PATCH 4.14 00/89] 4.14.170-stable review 93 (93) 2020/02/04 17:19
[PATCH 4.9 00/68] 4.9.213-stable review 72 (72) 2020/02/04 17:18
[PATCH v3] ttyprintk: fix a potential deadlock in interrupt context issue 1 (1) 2020/01/13 03:48
[PATCH RESEND] ttyprintk: fix a potential sleeping in interrupt context issue 4 (4) 2020/01/11 19:47
[PATCH] ttyprintk: fix a potential sleeping in interrupt context issue 2 (2) 2019/12/11 13:40
BUG: sleeping function called from invalid context in tpk_write 0 (1) 2019/12/07 17:25
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 BUG: sleeping function called from invalid context in tpk_write C done 10 1564d 1625d 1/1 fixed on 2020/03/06 21:15
linux-4.19 BUG: sleeping function called from invalid context in tpk_write C done 30 1564d 1625d 1/1 fixed on 2020/03/06 21:15

Sample crash report:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:938
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 13589, name: syz-executor680
2 locks held by syz-executor680/13589:
 #0: ffff88808d52b198 (&mm->mmap_sem#2){++++}, at: do_user_addr_fault arch/x86/mm/fault.c:1382 [inline]
 #0: ffff88808d52b198 (&mm->mmap_sem#2){++++}, at: __do_page_fault+0x33c/0xd80 arch/x86/mm/fault.c:1506
 #1: ffffc90000da8d50 ((&sp->resync_t)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:172 [inline]
 #1: ffffc90000da8d50 ((&sp->resync_t)){+.-.}, at: call_timer_fn+0xe0/0x780 kernel/time/timer.c:1394
Preemption disabled at:
[<ffffffff880000f3>] __do_softirq+0xf3/0x98c kernel/softirq.c:269
CPU: 1 PID: 13589 Comm: syz-executor680 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 ___might_sleep.cold+0x1fb/0x23e kernel/sched/core.c:6800
 __might_sleep+0x95/0x190 kernel/sched/core.c:6753
 __mutex_lock_common kernel/locking/mutex.c:938 [inline]
 __mutex_lock+0xc5/0x13c0 kernel/locking/mutex.c:1106
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1121
 tpk_write+0x5d/0x340 drivers/char/ttyprintk.c:122
 resync_tnc+0x1b6/0x320 drivers/net/hamradio/6pack.c:522
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:update_stack_state+0x48c/0x5f0 arch/x86/kernel/unwind_frame.c:239
Code: 01 00 0f 85 12 01 00 00 4d 8b 24 24 e9 b0 fe ff ff 49 8d 7d 38 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 01 00 <0f> 85 e0 00 00 00 48 8b 85 68 ff ff ff 49 c7 45 58 00 00 00 00 49
RSP: 0000:ffffc9001038f5d0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffffc9001038fad0 RCX: 1ffff92002071ef7
RDX: 0000000000000010 RSI: 1ffff92002071e00 RDI: ffffc9001038f7b8
RBP: ffffc9001038f698 R08: ffff88808481c380 R09: ffffc9001038f7d8
R10: ffffc9001038f7a8 R11: ffffc9001038f7b8 R12: ffffc9001038f770
R13: ffffc9001038f780 R14: 1ffff92002071ec2 R15: ffffc9001038f7c0
 unwind_next_frame.part.0+0x1a9/0xa20 arch/x86/kernel/unwind_frame.c:311
 unwind_next_frame+0x3b/0x50 arch/x86/kernel/unwind_frame.c:265
 arch_stack_walk+0x81/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xac/0xe0 kernel/stacktrace.c:123
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:521
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc mm/slab.c:3320 [inline]
 kmem_cache_alloc+0x121/0x710 mm/slab.c:3484
 anon_vma_chain_alloc mm/rmap.c:130 [inline]
 __anon_vma_prepare+0x62/0x3c0 mm/rmap.c:184
 anon_vma_prepare include/linux/rmap.h:153 [inline]
 do_huge_pmd_anonymous_page+0x132f/0x1a50 mm/huge_memory.c:714
 create_huge_pmd mm/memory.c:3836 [inline]
 __handle_mm_fault+0x3073/0x3da0 mm/memory.c:4046
 handle_mm_fault+0x3b2/0xa50 mm/memory.c:4112
 do_user_addr_fault arch/x86/mm/fault.c:1441 [inline]
 __do_page_fault+0x536/0xd80 arch/x86/mm/fault.c:1506
 do_page_fault+0x38/0x590 arch/x86/mm/fault.c:1530
 page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203
RIP: 0033:0x400daf
Code: 00 20 ba 23 54 00 00 bf 10 00 00 00 31 c0 e8 f8 59 04 00 eb bb 66 0f 1f 44 00 00 48 b8 2f 64 65 76 2f 74 74 79 45 31 c0 31 c9 <48> 89 04 25 40 15 00 20 b8 74 6b 00 00 c7 04 25 48 15 00 20 70 72
RSP: 002b:00007f9081c00dc0 EFLAGS: 00010246
RAX: 7974742f7665642f RBX: 00000000006dbc28 RCX: 0000000000000000
RDX: 00000000004467a9 RSI: 0000000000000081 RDI: 00000000006dbc2c
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffd73ac136f R14: 00007f9081c019c0 R15: 0000000000000000

================================
WARNING: inconsistent lock state
5.4.0-syzkaller #0 Tainted: G        W        
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
syz-executor680/13589 [HC0[0]:SC1[1]:HE1:SE0] takes:
ffffffff8c112af0 (&tpk_port.port_write_mutex){+.?.}, at: tpk_write+0x5d/0x340 drivers/char/ttyprintk.c:122
{SOFTIRQ-ON-W} state was registered at:
  lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485
  __mutex_lock_common kernel/locking/mutex.c:959 [inline]
  __mutex_lock+0x156/0x13c0 kernel/locking/mutex.c:1106
  mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1121
  tpk_write+0x5d/0x340 drivers/char/ttyprintk.c:122
  tnc_init drivers/net/hamradio/6pack.c:536 [inline]
  sixpack_open+0x8d6/0xaaf drivers/net/hamradio/6pack.c:632
  tty_ldisc_open.isra.0+0xa3/0x110 drivers/tty/tty_ldisc.c:464
  tty_set_ldisc+0x30e/0x6b0 drivers/tty/tty_ldisc.c:591
  tiocsetd drivers/tty/tty_io.c:2337 [inline]
  tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2597
  vfs_ioctl fs/ioctl.c:47 [inline]
  file_ioctl fs/ioctl.c:545 [inline]
  do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732
  ksys_ioctl+0xab/0xd0 fs/ioctl.c:749
  __do_sys_ioctl fs/ioctl.c:756 [inline]
  __se_sys_ioctl fs/ioctl.c:754 [inline]
  __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754
  do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
irq event stamp: 386
hardirqs last  enabled at (386): [<ffffffff81006743>] trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41
hardirqs last disabled at (385): [<ffffffff8100675f>] trace_hardirqs_off_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:42
softirqs last  enabled at (72): [<ffffffff812aa7ce>] memcpy include/linux/string.h:380 [inline]
softirqs last  enabled at (72): [<ffffffff812aa7ce>] fpu__copy+0x17e/0x8c0 arch/x86/kernel/fpu/core.c:195
softirqs last disabled at (291): [<ffffffff81478ceb>] invoke_softirq kernel/softirq.c:373 [inline]
softirqs last disabled at (291): [<ffffffff81478ceb>] irq_exit+0x19b/0x1e0 kernel/softirq.c:413

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&tpk_port.port_write_mutex);
  <Interrupt>
    lock(&tpk_port.port_write_mutex);

 *** DEADLOCK ***

2 locks held by syz-executor680/13589:
 #0: ffff88808d52b198 (&mm->mmap_sem#2){++++}, at: do_user_addr_fault arch/x86/mm/fault.c:1382 [inline]
 #0: ffff88808d52b198 (&mm->mmap_sem#2){++++}, at: __do_page_fault+0x33c/0xd80 arch/x86/mm/fault.c:1506
 #1: ffffc90000da8d50 ((&sp->resync_t)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:172 [inline]
 #1: ffffc90000da8d50 ((&sp->resync_t)){+.-.}, at: call_timer_fn+0xe0/0x780 kernel/time/timer.c:1394

stack backtrace:
CPU: 1 PID: 13589 Comm: syz-executor680 Tainted: G        W         5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 print_usage_bug.cold+0x327/0x378 kernel/locking/lockdep.c:3101
 valid_state kernel/locking/lockdep.c:3112 [inline]
 mark_lock_irq kernel/locking/lockdep.c:3309 [inline]
 mark_lock+0xbb4/0x1220 kernel/locking/lockdep.c:3666
 mark_usage kernel/locking/lockdep.c:3566 [inline]
 __lock_acquire+0x1e8e/0x4a00 kernel/locking/lockdep.c:3909
 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485
 __mutex_lock_common kernel/locking/mutex.c:959 [inline]
 __mutex_lock+0x156/0x13c0 kernel/locking/mutex.c:1106
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1121
 tpk_write+0x5d/0x340 drivers/char/ttyprintk.c:122
 resync_tnc+0x1b6/0x320 drivers/net/hamradio/6pack.c:522
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:update_stack_state+0x48c/0x5f0 arch/x86/kernel/unwind_frame.c:239
Code: 01 00 0f 85 12 01 00 00 4d 8b 24 24 e9 b0 fe ff ff 49 8d 7d 38 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 01 00 <0f> 85 e0 00 00 00 48 8b 85 68 ff ff ff 49 c7 45 58 00 00 00 00 49
RSP: 0000:ffffc9001038f5d0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffffc9001038fad0 RCX: 1ffff92002071ef7
RDX: 0000000000000010 RSI: 1ffff92002071e00 RDI: ffffc9001038f7b8
RBP: ffffc9001038f698 R08: ffff88808481c380 R09: ffffc9001038f7d8
R10: ffffc9001038f7a8 R11: ffffc9001038f7b8 R12: ffffc9001038f770
R13: ffffc9001038f780 R14: 1ffff92002071ec2 R15: ffffc9001038f7c0
 unwind_next_frame.part.0+0x1a9/0xa20 arch/x86/kernel/unwind_frame.c:311
 unwind_next_frame+0x3b/0x50 arch/x86/kernel/unwind_frame.c:265
 arch_stack_walk+0x81/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xac/0xe0 kernel/stacktrace.c:123
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:521
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc mm/slab.c:3320 [inline]
 kmem_cache_alloc+0x121/0x710 mm/slab.c:3484
 anon_vma_chain_alloc mm/rmap.c:130 [inline]
 __anon_vma_prepare+0x62/0x3c0 mm/rmap.c:184
 anon_vma_prepare include/linux/rmap.h:153 [inline]
 do_huge_pmd_anonymous_page+0x132f/0x1a50 mm/huge_memory.c:714
 create_huge_pmd mm/memory.c:3836 [inline]
 __handle_mm_fault+0x3073/0x3da0 mm/memory.c:4046
 handle_mm_fault+0x3b2/0xa50 mm/memory.c:4112
 do_user_addr_fault arch/x86/mm/fault.c:1441 [inline]
 __do_page_fault+0x536/0xd80 arch/x86/mm/fault.c:1506
 do_page_fault+0x38/0x590 arch/x86/mm/fault.c:1530
 page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203
RIP: 0033:0x400daf
Code: 00 20 ba 23 54 00 00 bf 10 00 00 00 31 c0 e8 f8 59 04 00 eb bb 66 0f 1f 44 00 00 48 b8 2f 64 65 76 2f 74 74 79 45 31 c0 31 c9 <48> 89 04 25 40 15 00 20 b8 74 6b 00 00 c7 04 25 48 15 00 20 70 72
RSP: 002b:00007f9081c00dc0 EFLAGS: 00010246
RAX: 7974742f7665642f RBX: 00000000006dbc28 RCX: 0000000000000000
RDX: 00000000004467a9 RSI: 0000000000000081 RDI: 00000000006dbc2c
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffd73ac136f R14: 00007f9081c019c0 R15: 0000000000000000
------------[ cut here ]------------
WARNING: CPU: 1 PID: 13589 at kernel/locking/mutex.c:737 mutex_unlock+0x1d/0x30 kernel/locking/mutex.c:744

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/07 23:36 upstream ad910e36da4c 1508f453 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/12/07 17:18 upstream eea2d5da29e3 85f26751 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/12/07 15:55 upstream eea2d5da29e3 85f26751 .config console log report syz C ci-upstream-kasan-gce-root
2019/12/20 02:05 linux-next 9f8535c5f75f 36650b4b .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/12/19 21:47 linux-next 9f8535c5f75f 36650b4b .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2020/01/17 20:30 upstream ab7541c3addd 3de7aabb .config console log report ci-upstream-kasan-gce-selinux-root
2020/01/12 04:25 upstream ac61145a725a 4c04afaa .config console log report ci-upstream-kasan-gce-selinux-root
2020/01/09 17:31 upstream b07f636fca1c 4de4e9f0 .config console log report ci-upstream-kasan-gce-root
2020/01/07 02:05 upstream ec7b3f5372e2 53430d97 .config console log report ci-upstream-kasan-gce-selinux-root
2020/01/06 01:10 upstream c79f46a28239 438e1227 .config console log report ci-upstream-kasan-gce-selinux-root
2020/01/03 03:01 upstream 7ca4ad5ba886 25a0186e .config console log report ci-upstream-kasan-gce-root
2020/01/11 04:19 linux-next 6c09d7dbb7d3 4de4e9f0 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.