syzbot


INFO: task hung in tty_release

Status: auto-closed as invalid on 2020/04/02 02:37
Reported-by: syzbot+02b8795eef027b1b6b0e@syzkaller.appspotmail.com
First crash: 2047d, last: 1594d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in tty_release serial 2 2100d 2100d 0/26 auto-closed as invalid on 2019/02/22 10:22
linux-4.14 INFO: task hung in tty_release 1 1509d 1509d 0/1 auto-closed as invalid on 2020/06/26 02:50

Sample crash report:
audit: type=1400 audit(1575426749.569:1234): avc:  denied  { net_admin } for  pid=17661 comm="syz-executor.2" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1575426750.519:1235): avc:  denied  { net_admin } for  pid=2085 comm="syz-executor.5" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
ip6_tunnel: l0 xmit: Local address not yet configured!
INFO: task syz-executor.3:25590 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.3  D28296 25590   2091 0x80000002
 ffff8801a69edf00 0000000000000000 ffff8801d3b82c00 ffff8801aa845f00
 ffff8801db721018 ffff88018b61f7a8 ffffffff828075c2 0000000000000000
 ffff8801a69ee7b0 ffffed0034d3dcf5 00ff8801a69edf00 ffff8801db7218f0
Call Trace:
 [<ffffffff82808aef>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff828094a3>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff8280b51d>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff8280b51d>] mutex_lock_nested+0x38d/0x900 kernel/locking/mutex.c:621
 [<ffffffff81d276f9>] tty_release+0xb79/0xe90 drivers/tty/tty_io.c:1938
 [<ffffffff81510293>] __fput+0x263/0x700 fs/file_table.c:208
 [<ffffffff815107b5>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8113dc4c>] task_work_run+0x10c/0x180 kernel/task_work.c:116
 [<ffffffff810e6c4d>] exit_task_work include/linux/task_work.h:21 [inline]
 [<ffffffff810e6c4d>] do_exit+0x78d/0x2a50 kernel/exit.c:833
 [<ffffffff810ed3a1>] do_group_exit+0x111/0x300 kernel/exit.c:937
 [<ffffffff8110eb61>] get_signal+0x4e1/0x1460 kernel/signal.c:2321
 [<ffffffff81052aa5>] do_signal+0x95/0x1b00 arch/x86/kernel/signal.c:807
 [<ffffffff81003e2e>] exit_to_usermode_loop+0x10e/0x150 arch/x86/entry/common.c:158
 [<ffffffff81005932>] prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 [<ffffffff81005932>] syscall_return_slowpath arch/x86/entry/common.c:263 [inline]
 [<ffffffff81005932>] do_syscall_64+0x3e2/0x550 arch/x86/entry/common.c:290
 [<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
1 lock held by rsyslogd/1900:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8156cc7c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/2027:
 #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
1 lock held by syz-executor.3/25590:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d276f9>] tty_release+0xb79/0xe90 drivers/tty/tty_io.c:1938
1 lock held by init/29378:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/29379:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/29380:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/29381:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/29382:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by init/29384:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open_by_driver drivers/tty/tty_io.c:2052 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d2bb96>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2130
1 lock held by syz-executor.3/29418:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d449c7>] ptmx_open+0xf7/0x310 drivers/tty/pty.c:753
1 lock held by syz-executor.3/29420:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81d449c7>] ptmx_open+0xf7/0x310 drivers/tty/pty.c:753

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

NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.141+ #1
 ffff8801d9907d08 ffffffff81b42e79 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810983b0 ffff8801d9907d40
 ffffffff81b4df89 0000000000000001 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 23709 Comm: syz-executor.1 Not tainted 4.9.141+ #1
task: ffff88019bd917c0 task.stack: ffff8801aefb0000
RIP: 0010:[<ffffffff81b5235a>] c [<ffffffff81b5235a>] radix_tree_lookup_slot+0x9a/0xc0 lib/radix-tree.c:728
RSP: 0018:ffff8801aefb7678  EFLAGS: 00000293
RAX: ffff88018c8d0f10 RBX: 1ffff10035df6ecf RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff81b52345 RDI: ffff8801d7c02900
RBP: ffff8801aefb76f0 R08: ffff88019bd920b8 R09: 4703c88318d76938
R10: ffff88019bd917c0 R11: 0000000000000001 R12: ffff88018c8d0f10
R13: 0000000000004a65 R14: dffffc0000000000 R15: ffff8801aefb79a8
FS:  00007fbd8dec9700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdb24de010 CR3: 000000019ba1c000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000000041b58ab3c ffffffff82e4b13ac ffffffff81b522c0c ffffffff8140b7b0c
 ffff88018c8d0f10c ffff8801d7c028f8c 0000000000004a65c dffffc0000000000c
 ffff8801aefb79a8c ffff8801aefb76d0c ffffffff81ba7f5cc 11d0f75b1c8c5af2c
Call Trace:
 [<ffffffff8140b83e>] find_get_entry+0x8e/0x570 mm/filemap.c:1093
 [<ffffffff8140bd51>] find_lock_entry+0x31/0x200 mm/filemap.c:1157
 [<ffffffff81460b1c>] shmem_getpage_gfp+0x19c/0x18f0 mm/shmem.c:1582
 [<ffffffff81465b63>] shmem_getpage mm/shmem.c:123 [inline]
 [<ffffffff81465b63>] shmem_file_read_iter+0x2b3/0xa30 mm/shmem.c:2282
 [<ffffffff815aad1d>] generic_file_splice_read+0x2bd/0x4e0 fs/splice.c:309
 [<ffffffff815ab39c>] do_splice_to+0x10c/0x170 fs/splice.c:899
 [<ffffffff815ab63f>] splice_direct_to_actor+0x23f/0x7e0 fs/splice.c:971
 [<ffffffff815abd83>] do_splice_direct+0x1a3/0x270 fs/splice.c:1080
 [<ffffffff8150d780>] do_sendfile+0x4f0/0xc30 fs/read_write.c:1393
 [<ffffffff8150f864>] SYSC_sendfile64 fs/read_write.c:1454 [inline]
 [<ffffffff8150f864>] SyS_sendfile64+0x144/0x160 fs/read_write.c:1440
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: cfd cff cff c48 c85 cc0 c74 c3d ce8 c24 c97 c7c cff c4c c8b c65 ca8 ce8 c1b c97 c7c cff c4c c89 ce0 c48 cba c00 c00 c00 c00 c00 cfc cff cdf c48 cc7 c04 c13 c00 c00 c00 c00 c<48> c8b c75 ce0 c65 c48 c33 c34 c25 c28 c00 c00 c00 c75 c10 c48 c83 cc4 c60 c5b c41 c

Crashes (21):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/04 02:36 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 ae13a849 .config console log report ci-android-49-kasan-gce
2019/10/27 00:55 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 25bb509e .config console log report ci-android-49-kasan-gce
2019/10/24 13:56 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 d01bb02a .config console log report ci-android-49-kasan-gce
2019/07/26 01:27 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 732bc5a0 .config console log report ci-android-49-kasan-gce
2019/05/03 20:45 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 d28f4ce5 .config console log report ci-android-49-kasan-gce
2019/04/12 04:14 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 13030ef8 .config console log report ci-android-49-kasan-gce
2019/03/17 19:25 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 ba18afea .config console log report ci-android-49-kasan-gce
2019/02/17 16:56 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 3e98cc30 .config console log report ci-android-49-kasan-gce
2019/02/13 04:08 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 1eedba36 .config console log report ci-android-49-kasan-gce
2018/11/21 07:46 https://android.googlesource.com/kernel/common android-4.9 109a48ed2f69 5d9a3924 .config console log report ci-android-49-kasan-gce
2018/09/24 13:52 https://android.googlesource.com/kernel/common android-4.9 1c57ba4f543b 2f485cdf .config console log report ci-android-49-kasan-gce
2018/09/23 20:42 https://android.googlesource.com/kernel/common android-4.9 1c57ba4f543b 28d9ac76 .config console log report ci-android-49-kasan-gce
2018/09/22 16:10 https://android.googlesource.com/kernel/common android-4.9 1c57ba4f543b 37079712 .config console log report ci-android-49-kasan-gce
2018/09/21 23:51 https://android.googlesource.com/kernel/common android-4.9 1c57ba4f543b 37079712 .config console log report ci-android-49-kasan-gce-root
2018/09/20 23:46 https://android.googlesource.com/kernel/common android-4.9 1c57ba4f543b 6cee973c .config console log report ci-android-49-kasan-gce
2018/09/09 15:26 https://android.googlesource.com/kernel/common android-4.9 dcae9fa1319b 6b5120a4 .config console log report ci-android-49-kasan-gce
2018/09/09 09:00 https://android.googlesource.com/kernel/common android-4.9 dcae9fa1319b 6b5120a4 .config console log report ci-android-49-kasan-gce
2018/09/06 22:38 https://android.googlesource.com/kernel/common android-4.9 dcae9fa1319b e30d3b52 .config console log report ci-android-49-kasan-gce
2018/09/06 14:55 https://android.googlesource.com/kernel/common android-4.9 dcae9fa1319b 0bb7a7eb .config console log report ci-android-49-kasan-gce
2019/07/17 20:28 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 f613a7c4 .config console log report ci-android-49-kasan-gce-386
2019/05/28 21:08 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 6bd61501 .config console log report ci-android-49-kasan-gce-386
* Struck through repros no longer work on HEAD.