INFO: task syz.1.1952:6053 blocked for more than 123 seconds. Not tainted 6.12.38-syzkaller-gd64d8b7dab32 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1952 state:D stack:0 pid:6053 tgid:6052 ppid:291 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285 rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4589 netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10868 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:3517 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e0/0x250 kernel/task_work.c:240 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9bc/0x2630 kernel/exit.c:953 do_group_exit+0x22a/0x300 kernel/exit.c:1095 get_signal+0x139d/0x14f0 kernel/signal.c:2933 arch_do_signal_or_restart+0x96/0x720 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+0x58/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f594dd8e9a9 RSP: 002b:00007f594eca0038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: 0000000000000034 RBX: 00007f594dfb5fa0 RCX: 00007f594dd8e9a9 RDX: 0000000000000000 RSI: 0000200000001e00 RDI: 0000000000000006 RBP: 00007f594de10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f594dfb5fa0 R15: 00007fffd10ddf88 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.38-syzkaller-gd64d8b7dab32 #0 b11b2e695edb96cef1ea16b3c17c686b1091986c Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2bf/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+0xd8f/0xed0 kernel/hung_task.c:423 kthread+0x2ca/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: 281 Comm: syz-executor Not tainted 6.12.38-syzkaller-gd64d8b7dab32 #0 b11b2e695edb96cef1ea16b3c17c686b1091986c Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:ifname_compare_aligned include/linux/netfilter/x_tables.h:414 [inline] RIP: 0010:ip6_packet_match net/ipv6/netfilter/ip6_tables.c:70 [inline] RIP: 0010:ip6t_do_table+0x7c3/0x14d0 net/ipv6/netfilter/ip6_tables.c:306 Code: 24 78 e8 30 d5 ec fc 48 8b 4c 24 78 48 8b 19 49 8d 7e 58 48 89 f8 48 c1 e8 03 42 80 3c 28 00 74 05 e8 11 d5 ec fc 49 33 5e 58 <4d> 8d 66 78 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 RSP: 0018:ffffc900000072e0 EFLAGS: 00000246 RAX: 1ffff110233eb813 RBX: 0000000000000000 RCX: ffffffff867127c8 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff888119f5c098 RBP: ffffc900000074d8 R08: ffff888119f5c000 R09: 0000000000000000 R10: ffffc90000007430 R11: fffff52000000e8a R12: ffff888119f5c090 R13: dffffc0000000000 R14: ffff888119f5c040 R15: 0000000000000000 FS: 0000555556f8f500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5b6f1ffff8 CR3: 0000000120a14000 CR4: 00000000003526b0 Call Trace: nf_hook_entry_hookfn include/linux/netfilter.h:155 [inline] nf_hook_slow+0xd5/0x240 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:272 [inline] NF_HOOK include/linux/netfilter.h:315 [inline] ipv6_rcv+0x1c7/0x220 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core net/core/dev.c:5757 [inline] __netif_receive_skb net/core/dev.c:5870 [inline] netif_receive_skb_internal net/core/dev.c:5956 [inline] netif_receive_skb+0x147/0x7b0 net/core/dev.c:6015 br_netif_receive_skb net/bridge/br_input.c:30 [inline] NF_HOOK include/linux/netfilter.h:317 [inline] br_pass_frame_up+0x126/0x1c0 net/bridge/br_input.c:70 br_handle_frame_finish+0x12d9/0x1720 net/bridge/br_input.c:221 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+0xf48/0x3940 net/core/dev.c:5651 __netif_receive_skb_one_core net/core/dev.c:5755 [inline] __netif_receive_skb net/core/dev.c:5870 [inline] process_backlog+0x3e5/0xae0 net/core/dev.c:6206 __napi_poll+0xd0/0x610 net/core/dev.c:6857 napi_poll net/core/dev.c:6926 [inline] net_rx_action+0x584/0xce0 net/core/dev.c:7048 handle_softirqs+0x1ab/0x630 kernel/softirq.c:621 __do_softirq+0xf/0x16 kernel/softirq.c:659 do_softirq+0xa6/0x100 kernel/softirq.c:503 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x54/0x60 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] release_sock+0x171/0x1f0 net/core/sock.c:3665 tcp_recvmsg+0x206/0x8e0 net/ipv4/tcp.c:2869 inet_recvmsg+0x139/0x4e0 net/ipv4/af_inet.c:890 sock_recvmsg_nosec net/socket.c:1052 [inline] sock_recvmsg+0x190/0x270 net/socket.c:1074 sock_read_iter+0x232/0x2f0 net/socket.c:1144 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x53d/0xb60 fs/read_write.c:570 ksys_read+0x141/0x250 fs/read_write.c:713 __do_sys_read fs/read_write.c:723 [inline] __se_sys_read fs/read_write.c:721 [inline] __x64_sys_read+0x7f/0x90 fs/read_write.c:721 x64_sys_call+0x2638/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:1 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f5b75b8d37d Code: a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb b5 e8 a8 48 00 00 0f 1f 84 00 00 00 00 00 80 3d c1 a1 1f 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec RSP: 002b:00007fff5683a2a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fff5683a3b0 RCX: 00007f5b75b8d37d RDX: 0000000000000004 RSI: 00007fff5683a2bc RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000001b4c83d7 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff5683a6d0 R13: 0000000000000004 R14: 00007fff5683a2bc R15: 00007fff5683a350 net_ratelimit: 80357 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:e6:4f:45:df:0d:ee, 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:e6:4f:45:df:0d:ee, 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:e6:4f:45:df:0d:ee, 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:e6:4f:45:df:0d:ee, 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:e6:4f:45:df:0d:ee, vlan:0) net_ratelimit: 117931 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:e6:4f:45:df:0d:ee, 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 veth0_to_bridge with own address as source address (addr:e6:4f:45:df:0d:ee, 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:e6:4f:45:df:0d:ee, 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:e6:4f:45:df:0d:ee, 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:e6:4f:45:df:0d:ee, vlan:0)