syzbot

INFO: task udevd:4359 blocked 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:25360 pid: 4359 ppid:  3561 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
 wait_on_page_bit_common+0x8bf/0xeb0 mm/filemap.c:1356
 wait_on_page_bit mm/filemap.c:1417 [inline]
 wait_on_page_locked include/linux/pagemap.h:688 [inline]
 wait_on_page_read mm/filemap.c:3437 [inline]
 do_read_cache_page+0xae6/0x1010 mm/filemap.c:3480
 read_mapping_page include/linux/pagemap.h:515 [inline]
 read_part_sector+0xd7/0x4c0 block/partitions/core.c:726
 adfspart_check_ICS+0xc3/0xe90 block/partitions/acorn.c:360
 check_partition block/partitions/core.c:148 [inline]
 blk_add_partitions block/partitions/core.c:611 [inline]
 bdev_disk_changed+0x936/0x1690 block/partitions/core.c:697
 blkdev_get_whole+0x2f9/0x390 block/bdev.c:682
 blkdev_get_by_dev+0x2da/0xa50 block/bdev.c:827
 blkdev_open+0x128/0x2c0 block/fops.c:466
 do_dentry_open+0x7f7/0xf90 fs/open.c:826
 do_open fs/namei.c:3616 [inline]
 path_openat+0x2718/0x2fb0 fs/namei.c:3750
 do_filp_open+0x1df/0x400 fs/namei.c:3777
 do_sys_openat2+0x14b/0x500 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0568c44407
RSP: 002b:00007fff8ee85750 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0568b56880 RCX: 00007f0568c44407
RDX: 00000000000a0800 RSI: 0000559d7ee92a50 RDI: ffffffffffffff9c
RBP: 0000559d7ee79910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000559d7ee91e00
R13: 0000559d7ee91410 R14: 0000000000000000 R15: 0000559d7ee91e00
 </TASK>
INFO: task syz.0.17:4437 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:27056 pid: 4437 ppid:  4357 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 blkdev_put+0xf1/0x780 block/bdev.c:915
 blkdev_close+0x76/0xa0 block/fops.c:478
 __fput+0x212/0x8c0 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0db86efe59
RSP: 002b:00007f0db7d51028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f0db8968fa0 RCX: 00007f0db86efe59
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000005
RBP: 00007f0db8785e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0db8969038 R14: 00007f0db8968fa0 R15: 00007ffe6f0cd3c8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31ef20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3950:
 #0: ffff88814d491098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
1 lock held by udevd/4292:
 #0: ffff88802067d918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x162/0xa50 block/bdev.c:820
1 lock held by udevd/4293:
 #0: ffff888020a8b918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x162/0xa50 block/bdev.c:820
1 lock held by udevd/4294:
 #0: ffff88802067f918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x162/0xa50 block/bdev.c:820
1 lock held by udevd/4359:
 #0: ffff888020a88918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x162/0xa50 block/bdev.c:820
1 lock held by syz.0.17/4437:
 #0: ffff888020a88918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf1/0x780 block/bdev.c:915
3 locks held by kworker/0:20/4457:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc9000319fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffff8880197df240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x283/0x3380 drivers/net/netdevsim/fib.c:1480
1 lock held by syz.1.126/4844:
 #0: ffff88802067d918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf1/0x780 block/bdev.c:915
1 lock held by syz.2.133/4877:
 #0: ffff88802067f918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf1/0x780 block/bdev.c:915
1 lock held by syz.3.138/4904:
 #0: ffff888020a8b918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf1/0x780 block/bdev.c:915

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe1b/0xe60 kernel/hung_task.c:369
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 154 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xc/0x60 kernel/kcov.c:206
Code: 89 fb e8 17 00 00 00 48 8b 3d 00 f0 10 0c 48 89 de 5b e9 b7 57 44 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d 14 7d 89 7e <65> 8b 15 15 7d 89 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
RSP: 0018:ffffc90001fe78b0 EFLAGS: 00000206
RAX: ffffffff894ecb7b RBX: 0000000000000008 RCX: ffff88801be23b80
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000040
RBP: 00000000000000f0 R08: ffffffff8d89e06f R09: 1ffffffff1b13c0d
R10: dffffc0000000000 R11: fffffbfff1b13c0e R12: 000000000000000b
R13: 00000000000000f0 R14: dffffc0000000000 R15: ffff88807ab5b3b0
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa3637e1540 CR3: 000000007eb39000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ieee80211_sta_get_rates+0x39b/0x6c0 net/mac80211/util.c:2128
 ieee80211_update_sta_info net/mac80211/ibss.c:1007 [inline]
 ieee80211_rx_bss_info net/mac80211/ibss.c:1121 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1614 [inline]
 ieee80211_ibss_rx_queued_mgmt+0xf79/0x2b50 net/mac80211/ibss.c:1643
 ieee80211_iface_process_skb net/mac80211/iface.c:1459 [inline]
 ieee80211_iface_work+0x714/0xc50 net/mac80211/iface.c:1513
 cfg80211_wiphy_work+0x224/0x260 net/wireless/core.c:433
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>