syzbot

 sign-in | mailing list | source | docs
🐞 Open [142] 🐞 Fixed [16] 🐞 Invalid [163] 📈 Kernel Health 📈 Bug Lifetimes 📈 Fuzzing 📈 Crashes 💬 Send us feedback

INFO: task hung in pipe_write (2)

Status: auto-closed as invalid on 2020/03/31 01:26
Reported-by: syzbot+299cf0f9e9b79d8112bf@syzkaller.appspotmail.com
First crash: 1605d, last: 1605d
▶ ▼ Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in pipe_write (3) fs 1 1550d 1550d 0/26 auto-closed as invalid on 2020/04/25 05:37
android-44 INFO: task hung in pipe_write 1 1965d 1836d 0/2 auto-closed as invalid on 2019/06/05 06:19
upstream INFO: task hung in rtnetlink_rcv_msg net C inconclusive inconclusive 913 42d 1887d 0/26 upstream: reported C repro on 2019/02/22 17:00
upstream INFO: task hung in pipe_write (2) ext4 C done 6 1679d 1678d 0/26 closed as invalid on 2019/09/28 02:25
upstream INFO: task hung in pipe_write fs 8 1909d 2023d 0/26 auto-closed as invalid on 2019/07/30 21:09
linux-4.14 INFO: task hung in pipe_write C 1 430d 548d 0/1 upstream: reported C repro on 2022/10/24 05:45
android-49 INFO: task hung in pipe_write C 3 1631d 1837d 0/3 public: reported C repro on 2019/04/14 08:51
linux-4.19 INFO: task hung in pipe_write C error 13 518d 1417d 0/1 upstream: reported C repro on 2020/06/07 01:40
upstream INFO: task hung in pipe_write (4) fs syz error 7 817d 1364d 0/26 auto-obsoleted due to no activity on 2022/10/22 17:00
android-414 INFO: task hung in pipe_write 1 1653d 1653d 0/1 auto-closed as invalid on 2020/02/11 22:17

Sample crash report:
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'syz-fuzzer' (2069) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved
INFO: task syz-executor.2:29544 blocked for more than 140 seconds.
      Not tainted 4.4.174+ #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D ffff880072a07a18 27296 29544   2124 0x00100004
 ffff880072a07a18 ffff8800b74f2f80 153ce00e304a5030 ffff8800b74f2f80
 0000000000000000 ffff8800b74f3800 ffff8801db71f180 ffff8801db71f1a8
 ffff8801db71e898 ffff880083f6af80 ffff8800b74f2f80 ffffed000e540001
Call Trace:
 [<ffffffff82709b79>] schedule+0x99/0x1d0 kernel/sched/core.c:3355
 [<ffffffff8270a333>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3388
 [<ffffffff8270c492>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff8270c492>] mutex_lock_nested+0x3c2/0xb80 kernel/locking/mutex.c:621
 [<ffffffff814b0528>] pipe_lock_nested fs/pipe.c:65 [inline]
 [<ffffffff814b0528>] pipe_lock fs/pipe.c:73 [inline]
 [<ffffffff814b0528>] pipe_wait+0x1b8/0x1e0 fs/pipe.c:121
 [<ffffffff814b0c05>] pipe_write+0x545/0xe70 fs/pipe.c:463
 [<ffffffff81496ae8>] new_sync_write fs/read_write.c:480 [inline]
 [<ffffffff81496ae8>] __vfs_write+0x2e8/0x3d0 fs/read_write.c:493
 [<ffffffff81498612>] vfs_write+0x182/0x4e0 fs/read_write.c:540
 [<ffffffff8149ac4c>] SYSC_write fs/read_write.c:587 [inline]
 [<ffffffff8149ac4c>] SyS_write+0xdc/0x1c0 fs/read_write.c:579
 [<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'init' (29617) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'syz-executor.3' (29585) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved
1 lock held by syz-executor.2/29544:
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff814b0528>] pipe_lock_nested fs/pipe.c:65 [inline]
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff814b0528>] pipe_lock fs/pipe.c:73 [inline]
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff814b0528>] pipe_wait+0x1b8/0x1e0 fs/pipe.c:121
Sending NMI to all CPUs:
NMI backtrace for cpu 0
CPU: 0 PID: 20 Comm: khungtaskd Not tainted 4.4.174+ #4
task: ffff8801da6f2f80 task.stack: ffff8801d9ed8000
RIP: 0010:[<ffffffff8109b617>]  [<ffffffff8109b617>] _flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:62 [inline]
RIP: 0010:[<ffffffff8109b617>]  [<ffffffff8109b617>] flat_send_IPI_mask+0xf7/0x1b0 arch/x86/kernel/apic/apic_flat_64.c:69
RSP: 0018:ffff8801d9edfc88  EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000c00 RCX: 0000000000000000
RDX: 0000000000000c00 RSI: 0000000000000000 RDI: ffffffffff5fc300
RBP: ffff8801d9edfcb8 R08: 0000000000000018 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000246
R13: 0000000003000000 R14: ffffffff82e5f2e0 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa6da32c9a8 CR3: 00000001d8788000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 0000000000000001 ffffffff82e5f2e0 ffffffff831a6ac0 fffffbfff0634c34
 000000000001b6c0 0000000000000008 ffff8801d9edfcd8 ffffffff81092bee
 0000000000000008 ffffffff82924260 ffff8801d9edfd30 ffffffff81ab8252
Call Trace:
 [<ffffffff81092bee>] nmi_raise_cpu_backtrace+0x5e/0x80 arch/x86/kernel/apic/hw_nmi.c:33
 [<ffffffff81ab8252>] nmi_trigger_all_cpu_backtrace.cold+0xa1/0xae lib/nmi_backtrace.c:85
 [<ffffffff81092ca4>] arch_trigger_all_cpu_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 [<ffffffff813b4762>] trigger_all_cpu_backtrace include/linux/nmi.h:44 [inline]
 [<ffffffff813b4762>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff813b4762>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff813b4762>] watchdog.cold+0xd3/0xee kernel/hung_task.c:238
 [<ffffffff811342c3>] kthread+0x273/0x310 kernel/kthread.c:211
 [<ffffffff82718fc5>] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:537
Code: 00 c3 5f ff 80 e6 10 75 e1 41 c1 e5 18 44 89 2c 25 10 c3 5f ff 44 89 fa 09 da 80 cf 04 41 83 ff 02 0f 44 d3 89 14 25 00 c3 5f ff <41> f7 c4 00 02 00 00 75 1e 4c 89 e7 57 9d 0f 1f 44 00 00 e8 f1 
NMI backtrace for cpu 1
CPU: 1 PID: 2070 Comm: syz-fuzzer Not tainted 4.4.174+ #4
task: ffff8800b7dd5f00 task.stack: ffff8801d7c98000
RIP: 0010:[<ffffffff8211e774>]  [<ffffffff8211e774>] lowmem_scan+0x404/0xbf0 drivers/staging/android/lowmemorykiller.c:125
RSP: 0018:ffff8801d7c9f3a0  EFLAGS: 00000246
RAX: 1ffff1003a4bc380 RBX: ffff8801d21a6340 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8211e754 RDI: ffff8801d25e1c00
RBP: ffff8801d7c9f440 R08: ffff8801d25e1f98 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8801d25e17c0 R14: 000000000000222d R15: 00000000000003e8
FS:  000000c4200283e8(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5584336b20 CR3: 00000001d8788000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 ffffffff8211e5af ffffffff00000816 00000000000001b8 0000000000000246
 ffffffff82ea7320 ffff8800b7dd5f00 00000000000126df ffff8801d7c9f518
 fffffbfff05c1200 0000223000000600 ffff8801d25e1f98 ffff8800b7fd5f00
Call Trace:
 [<ffffffff813ee8e2>] do_shrink_slab mm/vmscan.c:357 [inline]
 [<ffffffff813ee8e2>] shrink_slab.part.0+0x402/0xb30 mm/vmscan.c:455
 [<ffffffff813f742c>] shrink_slab mm/vmscan.c:425 [inline]
 [<ffffffff813f742c>] shrink_zone+0x4bc/0x610 mm/vmscan.c:2448
 [<ffffffff813f7bef>] shrink_zones mm/vmscan.c:2603 [inline]
 [<ffffffff813f7bef>] do_try_to_free_pages mm/vmscan.c:2653 [inline]
 [<ffffffff813f7bef>] try_to_free_pages+0x66f/0x1260 mm/vmscan.c:2861
 [<ffffffff813d09af>] __perform_reclaim mm/page_alloc.c:2915 [inline]
 [<ffffffff813d09af>] __alloc_pages_direct_reclaim mm/page_alloc.c:2936 [inline]
 [<ffffffff813d09af>] __alloc_pages_slowpath mm/page_alloc.c:3201 [inline]
 [<ffffffff813d09af>] __alloc_pages_nodemask+0x8af/0x14b0 mm/page_alloc.c:3313
 [<ffffffff813dc242>] __alloc_pages include/linux/gfp.h:415 [inline]
 [<ffffffff813dc242>] __alloc_pages_node include/linux/gfp.h:428 [inline]
 [<ffffffff813dc242>] alloc_pages_node include/linux/gfp.h:442 [inline]
 [<ffffffff813dc242>] __page_cache_alloc include/linux/pagemap.h:226 [inline]
 [<ffffffff813dc242>] page_cache_alloc_readahead include/linux/pagemap.h:242 [inline]
 [<ffffffff813dc242>] __do_page_cache_readahead+0x222/0x840 mm/readahead.c:184
 [<ffffffff813bf6de>] ra_submit mm/internal.h:55 [inline]
 [<ffffffff813bf6de>] do_sync_mmap_readahead mm/filemap.c:1917 [inline]
 [<ffffffff813bf6de>] filemap_fault+0x74e/0xc10 mm/filemap.c:1994
 [<ffffffff81665ed2>] ext4_filemap_fault+0x72/0xa0 fs/ext4/inode.c:5558
 [<ffffffff8142e82a>] __do_fault+0x1ca/0x350 mm/memory.c:2822
 [<ffffffff8143b9cc>] do_read_fault mm/memory.c:3012 [inline]
 [<ffffffff8143b9cc>] do_fault mm/memory.c:3177 [inline]
 [<ffffffff8143b9cc>] handle_pte_fault mm/memory.c:3346 [inline]
 [<ffffffff8143b9cc>] __handle_mm_fault mm/memory.c:3474 [inline]
 [<ffffffff8143b9cc>] handle_mm_fault+0x1cfc/0x3140 mm/memory.c:3503
 [<ffffffff810aaa4e>] __do_page_fault+0x28e/0x7f0 arch/x86/mm/fault.c:1243
 [<ffffffff810ab008>] do_page_fault+0x28/0x30 arch/x86/mm/fault.c:1306
 [<ffffffff82719e35>] page_fault+0x25/0x30 arch/x86/entry/entry_64.S:1064
Code: 75 ac 48 89 5d b8 e8 9c ae 1e ff 49 8d bd 40 04 00 00 48 89 f8 48 c1 e8 03 42 80 3c 20 00 0f 85 34 06 00 00 49 8b 9d 40 04 00 00 <4c> 8d ab c0 fb ff ff 48 81 fb 00 56 e1 82 0f 84 39 01 00 00 e8 
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'syz-fuzzer' (2070) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'init' (1) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'syz-fuzzer' (2069) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'syz-fuzzer' (2082) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'syz-fuzzer' (2069) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved
lowmemorykiller: Killing 'syz-executor.2' (29544) (tgid 29540), adj 1000,
   to free 38400kB on behalf of 'init' (1) because
   cache 440kB is below limit 6144kB for oom_score_adj 0
   Free memory is -1288kB above reserved

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/02 01:25 https://android.googlesource.com/kernel/common android-4.4 62872f952d6b f879db37 .config console log report ci-android-44-kasan-gce
* Struck through repros no longer work on HEAD.