INFO: task syz-executor:4269 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22000 pid:4269 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 io_schedule+0x7c/0xd0 kernel/sched/core.c:8798 folio_wait_bit_common+0x70a/0xfa0 mm/filemap.c:1324 __filemap_get_folio+0x423/0xdb0 mm/filemap.c:1959 truncate_inode_pages_range+0x402/0x1090 mm/truncate.c:402 evict+0x4dc/0x8d0 fs/inode.c:707 dispose_list fs/inode.c:738 [inline] evict_inodes+0x60c/0x6a0 fs/inode.c:792 generic_shutdown_super+0x93/0x340 fs/super.c:480 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 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: 0033:0x7f816479d9d7 RSP: 002b:00007fff75f30f08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f8164831f90 RCX: 00007f816479d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff75f30fc0 RBP: 00007fff75f30fc0 R08: 00007fff75f31fc0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff75f32050 R13: 00007f8164831f90 R14: 000000000004bcb3 R15: 00007fff75f32090 Showing all locks held in the system: 2 locks held by kworker/u4:0/9: #0: ffff8880b8e3ab18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:538 #1: ffff8880b8e27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x398/0x6d0 kernel/sched/psi.c:999 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2dfb0 (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: ffffffff8cb2e7d0 (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/28: #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4025: #0: ffff88807e5d0098 (&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/4269: #0: ffff8880537b80e0 (&type->s_umount_key#82){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 1 lock held by syz-executor/4804: #0: ffff888054d800e0 (&type->s_umount_key#82){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 1 lock held by syz-executor/10995: 6 locks held by syz.6.3312/13307: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: 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 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10995 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x1b/0x60 kernel/kcov.c:216 Code: 89 de 5b e9 47 22 50 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d 14 fa 7f 7e 65 8b 15 15 fa 7f 7e 81 e2 00 01 ff 00 74 11 <81> fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 RSP: 0018:ffffc900001dfdc8 EFLAGS: 00000206 RAX: ffffffff813a0b5d RBX: ffff88802d6e8a00 RCX: ffff88802c9cbb80 RDX: 0000000000000100 RSI: ffffffff8adf0dc0 RDI: ffff88802d6e8a00 RBP: ffffc900001dff20 R08: ffff88802c9cbb80 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000100 R12: ffff88802d6e8a10 R13: ffff8880494c3c78 R14: ffff888140e4d500 R15: ffffffff88ec310c FS: 0000555594653500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbe1af6e000 CR3: 0000000047b68000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __phys_addr+0xd/0x170 arch/x86/mm/physaddr.c:16 virt_to_folio include/linux/mm.h:913 [inline] virt_to_slab mm/slab.h:175 [inline] kmem_cache_free+0x6f/0x290 mm/slub.c:3709 kfree_skb include/linux/skbuff.h:1220 [inline] ip6_mc_input+0xa9c/0xcb0 net/ipv6/ip6_input.c:589 ip_sabotage_in+0x1f0/0x270 net/bridge/br_netfilter_hooks.c:1001 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xb9/0x200 net/netfilter/core.c:614 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x219/0x3b0 include/linux/netfilter.h:300 __netif_receive_skb_one_core net/core/dev.c:5594 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5708 netif_receive_skb_internal net/core/dev.c:5794 [inline] netif_receive_skb+0x1d4/0x830 net/core/dev.c:5853 NF_HOOK+0x9a/0x390 include/linux/netfilter.h:302 br_handle_frame_finish+0x121d/0x1670 net/bridge/br_input.c:204 br_nf_hook_thresh+0x3c9/0x4a0 net/bridge/br_netfilter_hooks.c:1184 br_nf_pre_routing_finish_ipv6+0x9da/0xd00 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:302 [inline] br_nf_pre_routing_ipv6+0x345/0x6b0 net/bridge/br_netfilter_ipv6.c:243 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_bridge_pre net/bridge/br_input.c:260 [inline] br_handle_frame+0x1167/0x13c0 net/bridge/br_input.c:406 __netif_receive_skb_core+0x1004/0x38f0 net/core/dev.c:5488 __netif_receive_skb_one_core net/core/dev.c:5592 [inline] __netif_receive_skb+0x74/0x290 net/core/dev.c:5708 process_backlog+0x38d/0x6f0 net/core/dev.c:6036 __napi_poll+0xc0/0x460 net/core/dev.c:6603 napi_poll net/core/dev.c:6670 [inline] net_rx_action+0x5dd/0xb20 net/core/dev.c:6784 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194 Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 0f 2c 22 f7 65 8b 05 d0 b0 cb 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90003d4fae0 EFLAGS: 00000206 RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: 0d507b661bd44600 RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: 0000000000000001 RBP: ffffc90003d4fb68 R08: ffffffff96efaf6b R09: 1ffffffff2ddf5ed R10: dffffc0000000000 R11: fffffbfff2ddf5ee R12: dffffc0000000000 R13: ffff8880458e8000 R14: ffffffff96efaf68 R15: 1ffff920007a9f5c __debug_check_no_obj_freed lib/debugobjects.c:988 [inline] debug_check_no_obj_freed+0x515/0x530 lib/debugobjects.c:1009 free_pages_prepare mm/page_alloc.c:1492 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x2a6/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383 getname_flags+0xb7/0x500 fs/namei.c:139 user_path_at_empty+0x28/0x60 fs/namei.c:2912 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1829 [inline] __do_sys_umount fs/namespace.c:1837 [inline] __se_sys_umount fs/namespace.c:1835 [inline] __x64_sys_umount+0xf9/0x170 fs/namespace.c:1835 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3790f9d9d7 Code: a2 c7 05 1c ed 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffc6d71e228 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f3791031f90 RCX: 00007f3790f9d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc6d71e2e0 RBP: 00007ffc6d71e2e0 R08: 00007ffc6d71f2e0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc6d71f370 R13: 00007f3791031f90 R14: 000000000006efbb R15: 00007ffc6d71f3b0 net_ratelimit: 4034 callbacks suppressed bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:1a:99:eb:55:b9:a5, vlan:0)