INFO: task syz.0.8:5945 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.8 state:D stack:24360 pid:5945 tgid:5944 ppid:5832 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 percpu_rwsem_wait+0x3b3/0x430 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xee/0x130 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:66 [inline] __sb_start_write include/linux/fs.h:1783 [inline] sb_start_write+0x184/0x1c0 include/linux/fs.h:1919 mnt_want_write+0x3f/0x90 fs/namespace.c:556 open_last_lookups fs/namei.c:3754 [inline] path_openat+0x82e/0x35d0 fs/namei.c:4001 do_filp_open+0x284/0x4e0 fs/namei.c:4031 do_sys_openat2+0x12b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x249/0x2a0 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff98818d169 RSP: 002b:00007ff988f3b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ff9883a5fa0 RCX: 00007ff98818d169 RDX: 000000000000275a RSI: 0000200000000080 RDI: ffffffffffffff9c RBP: 00007ff98820e990 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff9883a5fa0 R15: 00007ffe7d7fdb28 INFO: task syz.0.8:5954 blocked for more than 144 seconds. Not tainted 6.15.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.8 state:D stack:24360 pid:5954 tgid:5944 ppid:5832 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 percpu_rwsem_wait+0x3b3/0x430 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xee/0x130 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:66 [inline] __sb_start_write include/linux/fs.h:1783 [inline] sb_start_write+0x184/0x1c0 include/linux/fs.h:1919 mnt_want_write+0x3f/0x90 fs/namespace.c:556 filename_create+0x190/0x490 fs/namei.c:4090 do_mkdirat+0xbf/0x3f0 fs/namei.c:4349 __do_sys_mkdir fs/namei.c:4379 [inline] __se_sys_mkdir fs/namei.c:4377 [inline] __x64_sys_mkdir+0x6c/0x80 fs/namei.c:4377 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff98818d169 RSP: 002b:00007ff985ff6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ff9883a6160 RCX: 00007ff98818d169 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000200000000080 RBP: 00007ff98820e990 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff9883a6160 R15: 00007ffe7d7fdb28 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8ed434b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8ed434b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 3 locks held by kworker/u8:0/12: #0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000117c60 ( net_cleanup_work ){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] ){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900de690 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:608 1 lock held by khungtaskd/31: #0: ffffffff8ed3dfa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3dfa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3dfa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5580: #0: ffff88814cf220a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 1 lock held by syz.0.8/5945: #0: ffff88807eca2420 (sb_writers#14){++++}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 1 lock held by syz.0.8/5954: #0: ffff88807eca2420 (sb_writers#14){++++}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 3 locks held by kworker/u8:11/6841: #0: ffff88801cfcf148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801cfcf148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003e3fc60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003e3fc60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8ed434b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #2: ffffffff8ed434b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 2 locks held by syz-executor/7733: #0: ffff88804ad300e0 (&type->s_umount_key#50){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88804ad300e0 (&type->s_umount_key#50){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88804ad300e0 (&type->s_umount_key#50){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8ed43380 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 2 locks held by syz-executor/7899: #0: ffffffff8f46c308 (bio_slab_lock){+.+.}-{4:4}, at: bio_put_slab block/bio.c:140 [inline] #0: ffffffff8f46c308 (bio_slab_lock){+.+.}-{4:4}, at: bioset_exit+0x42d/0x650 block/bio.c:1664 #1: ffffffff8ed43380 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6843 Comm: kworker/u8:13 Not tainted 6.15.0-rc2-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:check_preemption_disabled+0x0/0x120 lib/smp_processor_id.c:13 Code: c7 80 e0 a0 8c 48 c7 c6 c0 e0 a0 8c eb 1c 66 66 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 <41> 57 41 56 41 55 41 54 53 48 83 ec 10 49 c7 c4 20 70 65 93 65 49 RSP: 0018:ffffc90003e0f440 EFLAGS: 00000282 RAX: 0000000000000001 RBX: 1ffff920007c1ea8 RCX: ffff88802b929e00 RDX: 0000000000000000 RSI: ffffffff8ca0e0c0 RDI: ffffffff8ca0e080 RBP: ffffc90003e0f578 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90003e0f540 R13: dffffc0000000000 R14: ffffffff822ab7b9 R15: ffffffff816debc8 FS: 0000000000000000(0000) GS:ffff8881250c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f940b240000 CR3: 0000000034f68000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:736 rcu_read_lock include/linux/rcupdate.h:842 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xe7/0x23b0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11e/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2389 [inline] slab_free mm/slub.c:4646 [inline] kmem_cache_free+0x197/0x410 mm/slub.c:4748 skb_kfree_head net/core/skbuff.c:1056 [inline] skb_free_head net/core/skbuff.c:1070 [inline] skb_release_data+0x67a/0x8b0 net/core/skbuff.c:1097 skb_release_all net/core/skbuff.c:1162 [inline] __kfree_skb net/core/skbuff.c:1176 [inline] sk_skb_reason_drop+0x1c9/0x380 net/core/skbuff.c:1214 kfree_skb_reason include/linux/skbuff.h:1279 [inline] kfree_skb include/linux/skbuff.h:1288 [inline] ieee80211_iface_work+0x28b/0x1100 net/mac80211/iface.c:1678 cfg80211_wiphy_work+0x2f0/0x490 net/wireless/core.c:435 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245