syzbot


INFO: task hung in tls_sk_proto_close (3)

Status: upstream: reported on 2026/04/15 08:35
Reported-by: syzbot+dfdbcce49884d291c82d@syzkaller.appspotmail.com
First crash: 30d, last: 2d06h
Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in tls_sk_proto_close 1 2 916d 964d 0/3 auto-obsoleted due to no activity on 2024/02/18 21:46
linux-5.15 INFO: task hung in tls_sk_proto_close (2) 1 1 821d 821d 0/3 auto-obsoleted due to no activity on 2024/05/24 11:00
linux-5.15 INFO: task hung in tls_sk_proto_close (3) 1 1 233d 233d 0/3 auto-obsoleted due to no activity on 2026/01/02 00:20
linux-5.15 INFO: task hung in tls_sk_proto_close 1 4 969d 1028d 0/3 auto-obsoleted due to no activity on 2023/12/28 14:26
upstream INFO: task hung in tls_sk_proto_close net 1 C done error 977 99d 2237d 0/29 auto-obsoleted due to no activity on 2026/04/16 05:24
linux-6.1 INFO: task hung in tls_sk_proto_close (2) 1 1 208d 208d 0/3 auto-obsoleted due to no activity on 2026/01/27 08:36
upstream INFO: task can't die in p9_fd_close 1 C done 58 1481d 2088d 0/29 closed as dup on 2022/08/26 12:44

Sample crash report:
INFO: task syz.6.1335:9694 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1335      state:D stack:25200 pid:9694  ppid:5600   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x2c7/0x5a0 kernel/sched/completion.c:138
 __flush_work+0x952/0xae0 kernel/workqueue.c:3076
 __cancel_work_timer+0x3f4/0x560 kernel/workqueue.c:3163
 tls_sk_proto_close+0xc4/0x8f0 net/tls/tls_main.c:328
 inet_release+0x139/0x180 net/ipv4/af_inet.c:430
 __sock_release net/socket.c:654 [inline]
 sock_close+0xd5/0x240 net/socket.c:1399
 __fput+0x22c/0x920 fs/file_table.c:320
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 get_signal+0x11a6/0x1350 kernel/signal.c:2648
 arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8885d9ce59
RSP: 002b:00007f8886cf9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: 0000000000110000 RBX: 00007f8886016090 RCX: 00007f8885d9ce59
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004
RBP: 00007f8885e32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 00000ffffffff004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8886016128 R14: 00007f8886016090 R15: 00007fff4edf6258
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2df70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cb2e790 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/27:
 #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4026:
 #0: ffff88802fbaa098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198
1 lock held by syz-executor/4288:
3 locks held by kworker/0:4/4328:
 #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc900047a7d00 ((work_completion)(&(&sw_ctx_tx->tx_work.work)->work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #2: ffff8880553ce4d8 (&ctx->tx_lock){+.+.}-{3:3}, at: tx_work_handler+0xfd/0x1f0 net/tls/tls_sw.c:2612
2 locks held by kworker/u4:26/5685:
1 lock held by syz.6.1335/9694:
 #0: ffff888053477410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #0: ffff888053477410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline]
 #0: ffff888053477410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1399
3 locks held by syz.5.1626/10927:
1 lock held by syz.2.1631/10936:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xeee/0xf30 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10927 Comm: syz.5.1626 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:65
Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01
RSP: 0018:ffffc900058fed08 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffc900058fede8 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc900058fee48
RBP: ffffffff8ea2bd0c R08: ffffc900058fee47 R09: ffffc900058fee38
R10: dffffc0000000000 R11: fffff52000b1fdc9 R12: 1ffff92000b1fdbe
R13: dffffc0000000000 R14: ffffc900058fee38 R15: ffffc900058fee1d
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd6f1fe8158 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 unwind_next_frame+0xb8a/0x20b0 arch/x86/kernel/unwind_orc.c:546
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 save_stack+0x121/0x230 mm/page_owner.c:127
 __reset_page_owner+0x51/0x1a0 mm/page_owner.c:148
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1486 [inline]
 free_pcp_prepare mm/page_alloc.c:1536 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413
 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3554
 release_pages+0x1fa6/0x2220 mm/swap.c:1035
 __pagevec_release+0x6d/0xe0 mm/swap.c:1055
 pagevec_release include/linux/pagevec.h:71 [inline]
 folio_batch_release include/linux/pagevec.h:135 [inline]
 shmem_undo_range+0x7c2/0x20c0 mm/shmem.c:946
 shmem_truncate_range mm/shmem.c:1062 [inline]
 shmem_evict_inode+0x25b/0xa80 mm/shmem.c:1171
 evict+0x4c9/0x8d0 fs/inode.c:705
 __dentry_kill+0x431/0x650 fs/dcache.c:611
 dentry_kill+0xb8/0x290 fs/dcache.c:-1
 dput+0xfa/0x1d0 fs/dcache.c:918
 __fput+0x5e0/0x920 fs/file_table.c:328
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0x982/0x2480 kernel/exit.c:880
 do_group_exit+0x217/0x2d0 kernel/exit.c:1022
 get_signal+0x1272/0x1350 kernel/signal.c:2871
 arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8bad59ce59
Code: Unable to access opcode bytes at 0x7f8bad59ce2f.
RSP: 002b:00007f8bae3a0028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007f8bad816090 RCX: 00007f8bad59ce59
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f8bad632d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8bad816128 R14: 00007f8bad816090 R15: 00007ffe5b4715e8
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/13 12:45 linux-6.1.y ad16b162f21d fec2a7ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in tls_sk_proto_close
2026/05/04 11:57 linux-6.1.y 4931e0e1673d 85f1bcf2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in tls_sk_proto_close
2026/04/29 00:10 linux-6.1.y 7c87defbd336 95008c03 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in tls_sk_proto_close
2026/04/28 11:46 linux-6.1.y 7c87defbd336 ce741359 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in tls_sk_proto_close
2026/04/16 03:52 linux-6.1.y 8e8fc038cad5 df15c5f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in tls_sk_proto_close
2026/04/15 08:34 linux-6.1.y 8e8fc038cad5 e2e976a8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in tls_sk_proto_close
* Struck through repros no longer work on HEAD.