INFO: task syz.2.1437:4978 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1437 state:D stack:0 pid:4978 tgid:4978 ppid:300 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:6027 [inline]
__schedule+0x14ce/0x2100 kernel/sched/core.c:7894
__schedule_loop kernel/sched/core.c:7975 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7990
schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x369/0x650 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
rcu_barrier+0x415/0x540 kernel/rcu/tree.c:4657
rcu_sync_dtor+0xaf/0x170 kernel/rcu/sync.c:187
percpu_free_rwsem+0x44/0x90 kernel/locking/percpu-rwsem.c:59
hci_uart_tty_close+0x210/0x230 drivers/bluetooth/hci_ldisc.c:564
tty_ldisc_close drivers/tty/tty_ldisc.c:455 [inline]
tty_ldisc_kill drivers/tty/tty_ldisc.c:613 [inline]
tty_ldisc_release+0x2aa/0x600 drivers/tty/tty_ldisc.c:781
tty_release_struct+0x2d/0xe0 drivers/tty/tty_io.c:1690
tty_release+0xc0a/0x1230 drivers/tty/tty_io.c:1861
__fput+0x1fb/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e5/0x260 kernel/task_work.c:246
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9ad/0x2720 kernel/exit.c:954
do_group_exit+0x229/0x2f0 kernel/exit.c:1096
get_signal+0x1398/0x14e0 kernel/signal.c:2933
arch_do_signal_or_restart+0xbc/0x760 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: 0033:0x7ff38795d68e
RSP: 002b:00007ff3887fbf58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007ff3887fc6c0 RCX: 00007ff38795d68e
RDX: 00007ff3887fbfb0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ff387a32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff387c16038 R14: 00007ff387c15fa0 R15: 00007ffc80e67c88
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 f08733504203045f02b8c772f2c0723d0fb183a2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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+0xdad/0xf00 kernel/hung_task.c:423
kthread+0x2c9/0x370 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: 20 Comm: rcuop/0 Not tainted syzkaller #0 f08733504203045f02b8c772f2c0723d0fb183a2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp4+0x32/0x90 kernel/kcov.c:288
Code: 48 8b 45 08 65 48 8b 15 7c 21 7d 7e 65 8b 0d 7d 21 7d 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba ec 0b 00 00 00 <74> 52 8b 8a c8 0b 00 00 83 f9 03 75 47 48 8b 8a d0 0b 00 00 44 8b
RSP: 0018:ffffc9000022ff10 EFLAGS: 00000246
RAX: ffffffff82e7294c RBX: ffff8881354926c8 RCX: 0000000000000100
RDX: ffff888103663900 RSI: 00000000e16dae5d RDI: 0000000001000000
RBP: ffffc9000022ff10 R08: ffff88815074e737 R09: 1ffff1102a0e9ce6
R10: dffffc0000000000 R11: ffffed102a0e9ce7 R12: 00000000e16dae5d
R13: 0000000000000000 R14: ffff8881354926c0 R15: ffff8881354926bc
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4e543a9ff8 CR3: 00000001762cc000 CR4: 00000000003526b0
Call Trace:
do_csum lib/checksum.c:77 [inline]
csum_partial+0x16c/0x300 lib/checksum.c:128
__skb_postpush_rcsum include/linux/skbuff.h:3986 [inline]
skb_postpush_rcsum include/linux/skbuff.h:4001 [inline]
skb_push_rcsum include/linux/skbuff.h:4020 [inline]
skb_checksum_trimmed+0x39d/0x710 net/core/skbuff.c:5976
ipv6_mc_check_icmpv6 net/ipv6/mcast_snoop.c:143 [inline]
ipv6_mc_check_mld+0x7de/0x20b0 net/ipv6/mcast_snoop.c:184
br_multicast_ipv6_rcv net/bridge/br_multicast.c:3949 [inline]
br_multicast_rcv+0x594/0x83c0 net/bridge/br_multicast.c:4033
br_handle_frame_finish+0x5bc/0x17a0 net/bridge/br_input.c:153
nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424
__netif_receive_skb_core+0xfae/0x3ab0 net/core/dev.c:5695
__netif_receive_skb_one_core net/core/dev.c:5799 [inline]
__netif_receive_skb net/core/dev.c:5914 [inline]
process_backlog+0x3e5/0xad0 net/core/dev.c:6250
__napi_poll+0xd0/0x610 net/core/dev.c:6901
napi_poll net/core/dev.c:6970 [inline]
net_rx_action+0x5ea/0xd80 net/core/dev.c:7092
handle_softirqs+0x1aa/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xb8/0x110 kernel/softirq.c:503
__local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_do_batch+0x5d9/0xd40 kernel/rcu/tree.c:2594
nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
rcu_nocb_cb_kthread+0x524/0xb30 kernel/rcu/tree_nocb.h:957
kthread+0x2c9/0x370 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
net_ratelimit: 115081 callbacks suppressed
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:aa:aa:aa:aa:aa:0c, 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:0c, 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)
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: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:0c, vlan:0)