syzbot


INFO: task hung in lock_sock_nested (2)

Status: auto-closed as invalid on 2020/01/08 15:18
Reported-by: syzbot+90fda4971e6c0f57526f@syzkaller.appspotmail.com
First crash: 1841d, last: 1722d
Similar bugs (14)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in lock_sock_nested (2) net C done 418 1543d 1556d 15/26 fixed on 2020/04/15 17:19
upstream INFO: task hung in lock_sock_nested net C 2593 1561d 2361d 0/26 closed as dup on 2017/12/23 20:15
android-44 INFO: task hung in lock_sock_nested (2) 4 1643d 1739d 0/2 auto-closed as invalid on 2020/03/27 01:37
linux-4.19 INFO: task hung in lock_sock_nested (3) 6 490d 704d 0/1 upstream: reported on 2022/06/23 22:52
upstream INFO: task hung in lock_sock_nested (3) net C done 5 1332d 1334d 15/26 fixed on 2020/11/16 12:12
linux-4.14 INFO: task hung in lock_sock_nested 1 1664d 1664d 0/1 auto-closed as invalid on 2020/03/06 15:38
linux-4.14 INFO: task hung in lock_sock_nested (2) 1 1401d 1401d 0/1 auto-closed as invalid on 2020/11/24 03:07
android-44 INFO: task hung in lock_sock_nested C 82 2281d 2283d 0/2 closed as invalid on 2019/03/08 00:11
upstream INFO: task can't die in __lock_sock bluetooth C done error 1067 203d 1017d 0/26 auto-obsoleted due to no activity on 2024/01/16 13:36
upstream INFO: task hung in lock_sock_nested (4) mptcp C done 6 1226d 1273d 19/26 fixed on 2021/03/10 01:48
android-49 INFO: task hung in lock_sock_nested C 101 1921d 2283d 0/3 closed as invalid on 2019/03/08 00:11
android-414 INFO: task hung in lock_sock_nested 65 1687d 1872d 0/1 auto-closed as invalid on 2020/02/12 04:11
linux-4.19 INFO: task hung in lock_sock_nested (2) 1 900d 900d 0/1 auto-closed as invalid on 2022/04/08 17:15
linux-4.19 INFO: task hung in lock_sock_nested 1 1480d 1480d 0/1 auto-closed as invalid on 2020/09/05 19:53

Sample crash report:
lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'getty' (20563) because
   cache 224kB is below limit 6144kB for oom_score_adj 0
   Free memory is -13360kB above reserved
INFO: task syz-executor.0:20539 blocked for more than 140 seconds.
      Not tainted 4.9.141+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D30200 20539   2088 0x00000004
 ffff8801801dc740 ffff8801cfdcdd80 ffff8801a77f9b80 ffff8801d1f25f00[  716.206817] lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'getty' (20563) because
   cache 224kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12592kB above reserved
 ffff8801db721018 ffff880167107ad8 ffffffff828075c2 ffff880167107b58
 ffff8801801dc740 ffffffff810efada 00fffc0000000000 ffff8801db7218f0
Call Trace:
 [<ffffffff82808aef>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff822acffc>] __lock_sock+0x13c/0x250 net/core/sock.c:2035
 [<ffffffff822ad206>] lock_sock_nested+0xf6/0x120 net/core/sock.c:2505
 [<ffffffff827d2640>] lock_sock include/net/sock.h:1404 [inline]
 [<ffffffff827d2640>] packet_setsockopt+0xc10/0x2630 net/packet/af_packet.c:3856
lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'udevd' (5889) because
   cache 228kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12496kB above reserved
 [<ffffffff822a4d76>] SYSC_setsockopt net/socket.c:1785 [inline]
 [<ffffffff822a4d76>] SyS_setsockopt+0x166/0x260 net/socket.c:1764
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c0cc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c0cc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813fe63f>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/2019:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82815952>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81d37362>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor.4/13781:
lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'syz-executor.0' (20536) because
   cache 228kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12496kB above reserved
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82815952>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81d37362>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor.2/17465:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82815952>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81d37362>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142

=============================================

lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'getty' (20566) because
   cache 228kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12496kB above reserved
lowmemorykiller: Killing 'syz-executor.0' (20536) (tgid 20534), adj 1000,
   to free 51424kB on behalf of 'getty' (20563) because
   cache 228kB is below limit 6144kB for oom_score_adj 0
   Free memory is -12496kB above reserved
NMI backtrace for cpu 0
CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.141+ #1
 ffff8801d9907d08 ffffffff81b42e79 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810983b0 ffff8801d9907d40
 ffffffff81b4df89 0000000000000000 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81b42e79>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b42e79>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81b4df89>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81b4df1c>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff810984b4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8131c65d>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8131c65d>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8131c65d>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8131c65d>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff81142c3d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff82817a5c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 1892 Comm: rsyslogd Not tainted 4.9.141+ #1
task: ffff8801d3da17c0 task.stack: ffff8801d6700000
RIP: 0010:[<ffffffff81207614>] c [<ffffffff81207614>] __lock_acquire+0x264/0x4a10 kernel/locking/lockdep.c:3262
RSP: 0000:ffff8801d67070f0  EFLAGS: 00000806
RAX: ffff8801d3da20e8 RBX: 00000000000000a0 RCX: 0000000000000002
RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffff8801d3da2108
RBP: ffff8801d67072a0 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8801d3da17c0 R11: 1ffff1003a7b4421 R12: 000000000000001e
R13: 0000000000000004 R14: ffffffff830cc360 R15: 0000000000000000
FS:  00007f2b17b87700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f28fc6e84bc CR3: 00000001d4b4b000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d3da17c0c dffffc0000000000c ffffffff83c73d80c ffffffff81206da7c
 000000000000322ac ffff8801d3da2128c ffff8801d3da2060c ffff8801d3da2130c
 ffff8801d3da2068c ffff8801d3da2070c 1ffff1003ace0e2ac ffffffff83c38ad0c
Call Trace:
 [<ffffffff8120c8d0>] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
 [<ffffffff81419fb6>] rcu_lock_acquire include/linux/rcupdate.h:493 [inline]
 [<ffffffff81419fb6>] rcu_read_lock include/linux/rcupdate.h:875 [inline]
 [<ffffffff81419fb6>] find_lock_task_mm+0x46/0x270 mm/oom_kill.c:112
 [<ffffffff821effdf>] lowmem_scan+0x34f/0xaf0 drivers/staging/android/lowmemorykiller.c:134
 [<ffffffff81449cc6>] do_shrink_slab mm/vmscan.c:398 [inline]
 [<ffffffff81449cc6>] shrink_slab.part.8+0x3c6/0xa00 mm/vmscan.c:501
 [<ffffffff814557fd>] shrink_slab mm/vmscan.c:465 [inline]
 [<ffffffff814557fd>] shrink_node+0x1ed/0x740 mm/vmscan.c:2602
 [<ffffffff814560c7>] shrink_zones mm/vmscan.c:2749 [inline]
 [<ffffffff814560c7>] do_try_to_free_pages mm/vmscan.c:2791 [inline]
 [<ffffffff814560c7>] try_to_free_pages+0x377/0xb80 mm/vmscan.c:3002
 [<ffffffff81428a01>] __perform_reclaim mm/page_alloc.c:3324 [inline]
 [<ffffffff81428a01>] __alloc_pages_direct_reclaim mm/page_alloc.c:3345 [inline]
 [<ffffffff81428a01>] __alloc_pages_slowpath mm/page_alloc.c:3697 [inline]
 [<ffffffff81428a01>] __alloc_pages_nodemask+0x981/0x1bd0 mm/page_alloc.c:3862
 [<ffffffff8143564a>] __alloc_pages include/linux/gfp.h:433 [inline]
 [<ffffffff8143564a>] __alloc_pages_node include/linux/gfp.h:446 [inline]
 [<ffffffff8143564a>] alloc_pages_node include/linux/gfp.h:460 [inline]
 [<ffffffff8143564a>] __page_cache_alloc include/linux/pagemap.h:208 [inline]
 [<ffffffff8143564a>] __do_page_cache_readahead+0x21a/0x8b0 mm/readahead.c:183
 [<ffffffff81415534>] ra_submit mm/internal.h:59 [inline]
 [<ffffffff81415534>] do_sync_mmap_readahead mm/filemap.c:2066 [inline]
 [<ffffffff81415534>] filemap_fault+0x924/0x1110 mm/filemap.c:2143
 [<ffffffff816e7721>] ext4_filemap_fault+0x71/0xa0 fs/ext4/inode.c:5853
 [<ffffffff81492ef3>] __do_fault+0x223/0x500 mm/memory.c:2833
 [<ffffffff814a3696>] do_read_fault mm/memory.c:3180 [inline]
 [<ffffffff814a3696>] do_fault mm/memory.c:3315 [inline]
 [<ffffffff814a3696>] handle_pte_fault mm/memory.c:3516 [inline]
 [<ffffffff814a3696>] __handle_mm_fault mm/memory.c:3603 [inline]
 [<ffffffff814a3696>] handle_mm_fault+0x1326/0x2350 mm/memory.c:3640
 [<ffffffff810b2b33>] __do_page_fault+0x403/0xa60 arch/x86/mm/fault.c:1406
 [<ffffffff810b31e7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff828188b5>] page_fault+0x25/0x30 arch/x86/entry/entry_64.S:951
Code: c01 c44 c89 ce8 c48 c8d c1c c80 c48 cc1 ce3 c03 c45 c85 ced c74 c4c c48 c8d c44 c1f cd8 c48 cbe c00 c00 c00 c00 c00 cfc cff cdf c48 c8d c78 c20 c49 c89 cfb c49 cc1 ceb c03 c<41> c0f cb6 c34 c33 c40 c84 cf6 c74 c0a c40 c80 cfe c03 c0f c8e c99 c13 c00 c00 c0f c

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/09/10 15:17 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 a60cb4cd .config console log report ci-android-49-kasan-gce
2019/05/14 14:11 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 ada3c44c .config console log report ci-android-49-kasan-gce-386
* Struck through repros no longer work on HEAD.