INFO: task syz.2.312:1402 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.312 state:D stack:0 pid:1402 tgid:1402 ppid:298 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6052 [inline]
__schedule+0x1496/0x20b0 kernel/sched/core.c:7865
__schedule_loop kernel/sched/core.c:7942 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7957
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8014
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rcu_barrier+0x4d/0x580 kernel/rcu/tree.c:4589
netdev_run_todo+0x118/0xce0 net/core/dev.c:10912
rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152
tun_detach drivers/net/tun.c:704 [inline]
tun_chr_close+0xc5/0x150 drivers/net/tun.c:3520
__fput+0x208/0xa30 fs/file_table.c:447
____fput+0x20/0x30 fs/file_table.c:475
task_work_run+0x1e8/0x260 kernel/task_work.c:246
resume_user_mode_work+0x35/0x50 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x63/0xb0 kernel/entry/common.c:218
do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f8e61d9ce59
RSP: 002b:00007ffe6ad61878 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f8e62017da0 RCX: 00007f8e61d9ce59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f8e62017da0 R08: 00007f8e62016128 R09: 0000000000000000
R10: 00000000003ffd5c R11: 0000000000000246 R12: 00000000000164e3
R13: 00007f8e6201609c R14: 000000000001626b R15: 00007ffe6ad61980
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 e549a79720f8b9d2445064a5e8a439d230f1aa2c
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
watchdog+0xe45/0xf90 kernel/hung_task.c:423
kthread+0x2c7/0x360 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1425 Comm: syz-executor Not tainted syzkaller #0 e549a79720f8b9d2445064a5e8a439d230f1aa2c
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:jhash2 include/linux/jhash.h:129 [inline]
RIP: 0010:hash_stack lib/stackdepot.c:514 [inline]
RIP: 0010:stack_depot_save_flags+0xa7/0x800 lib/stackdepot.c:614
Code: 44 89 e7 c1 c7 04 44 29 e1 31 cf 41 01 c4 29 f8 41 89 f8 41 c1 c0 06 41 31 c0 44 01 e7 45 89 c1 41 c1 c1 08 45 29 c4 45 31 e1 <41> 01 f8 44 29 cf 44 89 c9 c1 c1 10 31 f9 45 01 c1 89 c8 c1 c0 13
RSP: 0018:ffffc9000daa7520 EFLAGS: 00000202
RAX: 000000006de25310 RBX: 0000000000002800 RCX: 00000000704d7d5a
RDX: ffffc9000daa7628 RSI: 000000000000000a RDI: 0000000037412c4e
RBP: ffffc9000daa7580 R08: 00000000251c4e90 R09: 000000000d4e756d
R10: 000000000000000e R11: ffffffff81759b00 R12: 000000001100e548
R13: 1ffff11022b67a40 R14: ffffc9000daa75e0 R15: 1ffff92001b54eb8
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c04889e1f0 CR3: 00000000074aa000 CR4: 00000000003526b0
DR0: 000000000000002a DR1: ffffffffff7fff00 DR2: 0000000080000001
DR3: 0000000000000005 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
stack_depot_save+0x12/0x20 lib/stackdepot.c:686
save_stack+0x133/0x240 mm/page_owner.c:175
__reset_page_owner+0x79/0x450 mm/page_owner.c:315
reset_page_owner include/linux/page_owner.h:28 [inline]
free_pages_prepare mm/page_alloc.c:1390 [inline]
free_unref_page+0xbb8/0xf70 mm/page_alloc.c:2876
__free_pages+0x6b/0x3b0 mm/page_alloc.c:5402
vfree+0x3ea/0x5b0 mm/vmalloc.c:3408
kcov_put kernel/kcov.c:439 [inline]
kcov_close+0x2c/0x70 kernel/kcov.c:535
__fput+0x208/0xa30 fs/file_table.c:447
____fput+0x20/0x30 fs/file_table.c:475
task_work_run+0x1e8/0x260 kernel/task_work.c:246
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xa46/0x2850 kernel/exit.c:955
do_group_exit+0x21f/0x2f0 kernel/exit.c:1098
get_signal+0x134c/0x1490 kernel/signal.c:2933
arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fde19d57fd7
Code: Unable to access opcode bytes at 0x7fde19d57fad.
RSP: 002b:00007ffe35596370 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: 0000000000000028 RBX: 000055556c7d7500 RCX: 00007fde19d57fd7
RDX: 0000000000000028 RSI: 00007fde1ab44670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffe355963d4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fde1ab44670 R15: 0000000000000000
net_ratelimit: 93737 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:82:7a:6e:f0:6d:5f, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:82:7a:6e:f0:6d:5f, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
net_ratelimit: 99373 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:82:7a:6e:f0:6d:5f, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:82:7a:6e:f0:6d:5f, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)