INFO: task syz.2.436:6925 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.436 state:D stack:25712 pid: 6925 ppid: 4184 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537 rwsem_down_read_slowpath+0x548/0x9d0 kernel/locking/rwsem.c:1055 __down_read_common kernel/locking/rwsem.c:1239 [inline] __down_read kernel/locking/rwsem.c:1252 [inline] down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500 iterate_supers+0xa4/0x1d0 fs/super.c:716 quota_sync_all fs/quota/quota.c:68 [inline] __do_sys_quotactl fs/quota/quota.c:936 [inline] __se_sys_quotactl+0x33b/0x6f0 fs/quota/quota.c:915 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: 0033:0x7f6100abeeb9 RSP: 002b:00007f60fed1a028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007f6100d39fa0 RCX: 00007f6100abeeb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102 RBP: 00007f6100b2cc1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6100d3a038 R14: 00007f6100d39fa0 R15: 00007fff64ab9c38 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3946: #0: ffff88814cfe0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 4 locks held by kworker/u4:12/5044: #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc90003ec7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffffffff8d43c548 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 #3: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #3: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845 1 lock held by syz-executor/5590: #0: ffff8880588380e0 (&type->s_umount_key#84){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 1 lock held by syz.2.436/6925: #0: ffff8880588380e0 (&type->s_umount_key#84){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716 1 lock held by syz-executor/9699: #0: ffffffff8d43c548 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d43c548 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ee/0xf30 net/core/rtnetlink.c:5681 2 locks held by sed/9791: ============================================= 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 01/24/2026 Call Trace: 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+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5044 Comm: kworker/u4:12 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: phy17 ieee80211_iface_work RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:-1 [inline] RIP: 0010:debug_check_no_obj_freed+0x1e2/0x530 lib/debugobjects.c:1003 Code: 0f 84 3a 03 00 00 49 89 ee 49 c1 ee 03 41 80 3c 16 00 74 12 48 89 ef e8 bc fb d5 fd 48 ba 00 00 00 00 00 fc ff df 48 8b 45 00 <48> 89 04 24 4c 8d 7d 18 4c 89 f8 48 c1 e8 03 80 3c 10 00 74 12 4c RSP: 0018:ffffc90003ec7a88 EFLAGS: 00000046 RAX: ffff888060a515e8 RBX: 0000000000000004 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90003ec7960 RBP: ffff888060a51888 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520007d8f2c R12: ffff88805c0215e8 R13: ffff88805c021500 R14: 1ffff1100c14a311 R15: ffff888050b01630 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000276030 CR3: 00000000445dc000 CR4: 00000000003506f0 Call Trace: slab_free_hook mm/slub.c:1685 [inline] slab_free_freelist_hook+0x8b/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3520 kfree_skb include/linux/skbuff.h:1118 [inline] ieee80211_iface_work+0x798/0xc60 net/mac80211/iface.c:1515 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287