INFO: task udevd:5804 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:22880 pid:5804  tgid:5804  ppid:4973   task_flags:0x400140 flags:0x00080800
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x16ec/0x5620 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7283
 io_schedule+0x7f/0xd0 kernel/sched/core.c:8110
 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
 __wait_on_bit_lock+0xe3/0x4b0 kernel/sched/wait_bit.c:93
 out_of_line_wait_on_bit_lock+0x13b/0x190 kernel/sched/wait_bit.c:120
 wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline]
 __lock_buffer fs/buffer.c:71 [inline]
 lock_buffer include/linux/buffer_head.h:432 [inline]
 block_read_full_folio+0x38f/0x830 fs/buffer.c:2336
 filemap_read_folio+0x137/0x3b0 mm/filemap.c:2502
 filemap_update_page mm/filemap.c:2589 [inline]
 filemap_get_pages+0x16de/0x1e70 mm/filemap.c:2719
 filemap_read+0x44a/0x1240 mm/filemap.c:2806
 blkdev_read_iter+0x311/0x440 block/fops.c:855
 new_sync_read fs/read_write.c:493 [inline]
 vfs_read+0x58b/0xa80 fs/read_write.c:574
 ksys_read+0x156/0x270 fs/read_write.c:717
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8628b76407
RSP: 002b:00007ffd6dc866f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f8628a88880 RCX: 00007f8628b76407
RDX: 0000000000000200 RSI: 00007f862813b000 RDI: 0000000000000009
RBP: 000055feffbfe4d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000018
R13: 0000000000001000 R14: 000055feffc013c8 R15: 00007f86292cc39c
 </TASK>
INFO: task syz.6.377:8230 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.377       state:D stack:25592 pid:8230  tgid:8229  ppid:7229   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x16ec/0x5620 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7283
 io_schedule+0x7f/0xd0 kernel/sched/core.c:8110
 folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1324
 folio_lock include/linux/pagemap.h:1159 [inline]
 __find_get_block_slow fs/buffer.c:205 [inline]
 find_get_block_common+0x34f/0xe10 fs/buffer.c:1305
 bdev_getblk+0x53/0x6e0 include/linux/gfp.h:-1
 __getblk include/linux/buffer_head.h:380 [inline]
 sb_getblk include/linux/buffer_head.h:386 [inline]
 __ext4_get_inode_loc+0x7d8/0xfa0 fs/ext4/inode.c:4915
 ext4_get_inode_loc fs/ext4/inode.c:5018 [inline]
 ext4_reserve_inode_write+0x18b/0x360 fs/ext4/inode.c:6372
 ext4_xattr_set_handle+0x537/0x14c0 fs/ext4/xattr.c:2399
 ext4_initxattrs+0x9f/0x110 fs/ext4/xattr_security.c:44
 security_inode_init_security+0x296/0x3d0 security/security.c:1370
 __ext4_new_inode+0x3319/0x3ce0 fs/ext4/ialloc.c:1330
 ext4_mkdir+0x3e1/0xc60 fs/ext4/namei.c:3012
 vfs_mkdir+0x40b/0x630 fs/namei.c:5271
 filename_mkdirat+0x289/0x520 fs/namei.c:5304
 __do_sys_mkdirat fs/namei.c:5325 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb3c31cbcc7
RSP: 002b:00007fb3c1425e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fb3c1425ee0 RCX: 00007fb3c31cbcc7
RDX: 00000000000001ff RSI: 00002000000001c0 RDI: 00000000ffffff9c
RBP: 00002000000024c0 R08: 0000200000000240 R09: 0000000000000000
R10: 00002000000024c0 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007fb3c1425ea0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/38:
 #0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
8 locks held by kworker/u8:2/42:
2 locks held by kworker/u8:3/56:
 #0: ffff88801a074938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801a074938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc9000122fc40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc9000122fc40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
7 locks held by kworker/u8:6/182:
5 locks held by kworker/u8:10/1423:
 #0: ffff88801b290938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801b290938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc90006a7fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc90006a7fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f3417e0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673
 #3: ffff888034f61878 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x310 drivers/net/wireguard/device.c:249
 #4: ffffffff8dfce2b0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
3 locks held by kworker/u8:12/1462:
3 locks held by kworker/u8:14/3332:
 #0: ffff88801fad7138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801fad7138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc9000eaefc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc9000eaefc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffff88801b6bc0d0 (&type->s_umount_key#43){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
2 locks held by getty/5364:
 #0: ffff8880332620a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5593:
1 lock held by udevd/5797:
 #0: ffff888035cfc480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
2 locks held by udevd/5804:
 #0: ffff888022aa6608 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1044 [inline]
 #0: ffff888022aa6608 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:854
 #1: ffff888022aa67d8 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1094 [inline]
 #1: ffff888022aa67d8 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_update_page mm/filemap.c:2555 [inline]
 #1: ffff888022aa67d8 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_get_pages+0x931/0x1e70 mm/filemap.c:2719
2 locks held by udevd/5810:
 #0: ffff888021319db0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_downgrade include/linux/mmap_lock.h:586 [inline]
 #0: ffff888021319db0 (&mm->mmap_lock){++++}-{4:4}, at: vms_complete_munmap_vmas+0x247/0xc60 mm/vma.c:1340
 #1: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #1: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: free_one_page+0x43/0x250 mm/page_alloc.c:1549
1 lock held by udevd/5826:
 #0: ffff88801c6d4480 (sb_writers){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
2 locks held by udevd/5828:
 #0: ffffffff8e109930 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
 #0: ffffffff8e109930 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:294
 #1: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #1: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: free_one_page+0x43/0x250 mm/page_alloc.c:1549
1 lock held by udevd/5842:
 #0: ffff888035cfc480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
1 lock held by udevd/7020:
 #0: ffff888035cfc480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
3 locks held by syz.6.377/8230:
 #0: ffff888028e24480 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
 #1: ffff888040d3ee70 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1074 [inline]
 #1: ffff888040d3ee70 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2914 [inline]
 #1: ffff888040d3ee70 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2938 [inline]
 #1: ffff888040d3ee70 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4950
 #2: ffff8880622ac798 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline]
 #2: ffff8880622ac798 (&ei->xattr_sem){++++}-{4:4}, at: ext4_xattr_set_handle+0x19c/0x14c0 fs/ext4/xattr.c:2374
2 locks held by udevd/8371:
1 lock held by syz.5.476/8885:
 #0: ffff888028e240d0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
 #0: ffff888028e240d0 (&type->s_umount_key#32){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by udevd/8972:
 #0: ffff888035cfc480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
1 lock held by udevd/8974:
 #0: ffff888035cfc480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
1 lock held by udevd/8975:
 #0: ffff888035cfc480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
1 lock held by udevd/8976:
 #0: ffff888035cfc480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
1 lock held by syz-executor/9161:
 #0: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #0: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: free_one_page+0x43/0x250 mm/page_alloc.c:1549
5 locks held by syz-executor/9186:
 #0: ffff8880405f51b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline]
 #0: ffff8880405f51b0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x194/0x9e0 mm/mmap.c:1284
 #1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290
 #2: ffff88803c3d3598 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #2: ffff88803c3d3598 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
 #3: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #3: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #3: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
 #3: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
 #4: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #4: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: rmqueue_buddy mm/page_alloc.c:3211 [inline]
 #4: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: rmqueue mm/page_alloc.c:3403 [inline]
 #4: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}, at: get_page_from_freelist+0xcae/0x2930 mm/page_alloc.c:3938
5 locks held by segctord/9841:
2 locks held by syz.4.610/9847:
 #0: ffff88802175deb0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_downgrade include/linux/mmap_lock.h:586 [inline]
 #0: ffff88802175deb0 (&mm->mmap_lock){++++}-{4:4}, at: vms_complete_munmap_vmas+0x247/0xc60 mm/vma.c:1340
 #1: ffff88813fffc358 (&zone->lock){+.+.}-{3:3}
, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:652
1 lock held by modprobe/9857:
7 locks held by syz-executor/9858:
1 lock held by dhcpcd-run-hook/9859:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xfd3/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8975 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:security_sock_rcv_skb+0x0/0x270 security/security.c:4419
Code: fd e9 15 fe ff ff e8 2f 85 69 fd e9 15 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 41 57 41 56 53 48 89 f3 49 89 fe e8 fb 84 69 fd eb
RSP: 0018:ffffc900061df838 EFLAGS: 00000293
RAX: ffffffff88fd2861 RBX: ffff888037908b00 RCX: ffff888031ed9ec0
RDX: 0000000000000000 RSI: ffff888044fd7780 RDI: ffff888037908b00
RBP: ffffc900061df970 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f10dff R12: dffffc0000000000
R13: 1ffff92000c3bf18 R14: ffff888044fd7780 R15: 0000000000000000
FS:  00007f8628a88880(0000) GS:ffff888126187000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555878ce4e8 CR3: 0000000064e12000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 sk_filter_trim_cap+0x172/0xce0 net/core/filter.c:152
 sk_filter include/linux/filter.h:1101 [inline]
 unix_dgram_sendmsg+0x7c3/0x18d0 net/unix/af_unix.c:2176
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 sock_write_iter+0x4a1/0x4f0 net/socket.c:1254
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x629/0xba0 fs/read_write.c:688
 ksys_write+0x156/0x270 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8628b76407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd6dc8bbe0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8628a88880 RCX: 00007f8628b76407
RDX: 0000000000000000 RSI: 00007ffd6dc8bc87 RDI: 000000000000000a
RBP: 000000000000000a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007f8628a886e8
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>