INFO: task syz.6.1178:4087 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.1178 state:D stack:0 pid:4087 tgid:4087 ppid:4062 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 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_state+0x19/0x40 kernel/sched/completion.c:264 __wait_rcu_gp+0x296/0x2c0 kernel/rcu/update.c:516 synchronize_rcu_normal+0x14c/0x1d0 kernel/rcu/tree.c:4043 synchronize_rcu+0x98/0x2f0 kernel/rcu/tree.c:4121 rcu_sync_enter+0x213/0x350 kernel/rcu/sync.c:133 percpu_down_write+0x7c/0x600 kernel/locking/percpu-rwsem.c:257 hci_uart_tty_close+0x108/0x230 drivers/bluetooth/hci_ldisc.c:548 tty_ldisc_close drivers/tty/tty_ldisc.c:455 [inline] tty_ldisc_kill drivers/tty/tty_ldisc.c:613 [inline] tty_ldisc_release+0x2ad/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+0x9e3/0x2650 kernel/exit.c:953 do_group_exit+0x229/0x2f0 kernel/exit.c:1095 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 ret_from_fork+0x3a/0xa0 arch/x86/kernel/process.c:162 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 RIP: 0033:0x7f809659bf79 RSP: 002b:00007f8094ff6fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: 0000000000000000 RBX: 00007f8096815fa0 RCX: 00007f809659bf79 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f80966327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8096816038 R14: 00007f8096815fa0 R15: 00007ffe36987e08 INFO: task syz.1.2126:7001 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2126 state:D stack:0 pid:7001 tgid:7001 ppid:5453 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 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 netdev_run_todo+0x118/0xce0 net/core/dev.c:10874 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 ppp_release+0xf5/0x200 drivers/net/ppp/ppp_generic.c:423 __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+0x9e3/0x2650 kernel/exit.c:953 do_group_exit+0x229/0x2f0 kernel/exit.c:1095 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: 0033:0x7fd2f1d9bf79 RSP: 002b:00007fffb3be1f98 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffdfc RBX: 0000000000056b56 RCX: 00007fd2f1d9bf79 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd2f2015fac RBP: 0000000000000bea R08: 7fffffffffffffff R09: 0000000000000000 R10: 00007fffb3be20a0 R11: 0000000000000246 R12: 00007fffb3be20c0 R13: 00007fd2f2015fac R14: 0000000000057740 R15: 00007fffb3be20a0 INFO: task syz.3.2149:7064 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.2149 state:D stack:0 pid:7064 tgid:7064 ppid:291 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 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_state+0x19/0x40 kernel/sched/completion.c:264 __wait_rcu_gp+0x296/0x2c0 kernel/rcu/update.c:516 synchronize_rcu_normal+0x14c/0x1d0 kernel/rcu/tree.c:4043 synchronize_rcu+0x98/0x2f0 kernel/rcu/tree.c:4121 bcm_release+0x638/0x8d0 net/can/bcm.c:1642 __sock_release net/socket.c:659 [inline] sock_close+0xda/0x280 net/socket.c:1427 __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 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: 0033:0x7f452bf9bf79 RSP: 002b:00007ffd40a434c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f452c217da0 RCX: 00007f452bf9bf79 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f452c217da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f452c217cb0 R11: 0000000000000246 R12: 000000000005aaa7 R13: 00007f452c21609c R14: 000000000005aa75 R15: 00007f452c216090 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 a14c28d9e62c02dc866229d1d178db2aa7df2752 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 17 Comm: ksoftirqd/0 Not tainted syzkaller #0 a14c28d9e62c02dc866229d1d178db2aa7df2752 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:60 [inline] RIP: 0010:update_stack_state+0x1ef/0x4b0 arch/x86/kernel/unwind_frame.c:228 Code: 95 c0 48 8b 55 b0 4c 39 fa 0f 93 c1 20 c1 4c 39 f2 0f 92 c0 20 c8 3c 01 75 17 48 8b 8d 78 ff ff ff 4c 39 f9 0f 97 c0 4c 39 f1 <0f> 96 c1 84 c8 75 6e 49 bd 00 00 00 00 00 fc ff df 48 8b 85 68 ff RSP: 0018:ffffc90000117278 EFLAGS: 00000283 RAX: 0000000000000001 RBX: ffffc900001173c8 RCX: ffffc90000117738 RDX: ffffc90000117728 RSI: 1ffff92000022e7a RDI: ffffc90000117420 RBP: ffffc90000117338 R08: ffffc90000117490 R09: ffffc90000117488 R10: 0000000000000000 R11: ffffffff8175cbd0 R12: ffffc900001173c8 R13: 0000000000000001 R14: ffffc90000118000 R15: ffffc90000110000 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe6da345000 CR3: 0000000105bfa000 CR4: 00000000003526b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: unwind_next_frame+0x3c1/0x750 arch/x86/kernel/unwind_frame.c:315 arch_stack_walk+0x138/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:49 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:70 kasan_save_free_info+0x4a/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:249 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2445 [inline] slab_free mm/slub.c:4714 [inline] kmem_cache_free+0x1bd/0x4f0 mm/slub.c:4821 kfree_skbmem net/core/skbuff.c:-1 [inline] __kfree_skb+0x18f/0x210 net/core/skbuff.c:1203 sk_skb_reason_drop+0xd8/0x310 net/core/skbuff.c:1240 kfree_skb_reason include/linux/skbuff.h:1271 [inline] kfree_skb include/linux/skbuff.h:1280 [inline] ip6_mc_input+0x516/0x6c0 net/ipv6/ip6_input.c:587 dst_input include/net/dst.h:469 [inline] ip6_rcv_finish+0x360/0x3e0 net/ipv6/ip6_input.c:79 NF_HOOK include/linux/netfilter.h:317 [inline] ipv6_rcv+0xf1/0x240 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core net/core/dev.c:5763 [inline] __netif_receive_skb net/core/dev.c:5876 [inline] process_backlog+0x44b/0xad0 net/core/dev.c:6212 __napi_poll+0xd0/0x610 net/core/dev.c:6863 napi_poll net/core/dev.c:6932 [inline] net_rx_action+0x5ea/0xd80 net/core/dev.c:7054 handle_softirqs+0x1aa/0x630 kernel/softirq.c:621 run_ksoftirqd+0x20/0x30 kernel/softirq.c:999 smpboot_thread_fn+0x48f/0x8b0 kernel/smpboot.c:164 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: 124451 callbacks suppressed 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 veth0_to_bridge with own address as source address (addr:c6:a3:c5:6f:f3:5a, 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: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 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)