INFO: task syz.4.438:10476 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.438 state:D stack:24616 pid:10476 tgid:10475 ppid:8423 task_flags:0x400140 flags:0x00004006 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 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_write_slowpath+0xedd/0x1420 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1da/0x220 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:867 [inline] vfs_rename+0x6b9/0xf10 fs/namei.c:5051 do_renameat2+0xc8d/0x1290 fs/namei.c:5235 __do_sys_renameat2 fs/namei.c:5269 [inline] __se_sys_renameat2 fs/namei.c:5266 [inline] __x64_sys_renameat2+0xce/0xe0 fs/namei.c:5266 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efc8058e169 RSP: 002b:00007efc81353038 EFLAGS: 00000246 ORIG_RAX: 000000000000013c RAX: ffffffffffffffda RBX: 00007efc807b5fa0 RCX: 00007efc8058e169 RDX: 0000000000000005 RSI: 0000200000000240 RDI: 0000000000000005 RBP: 00007efc80610a68 R08: 0000000000000000 R09: 0000000000000000 R10: 00002000000001c0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007efc807b5fa0 R15: 00007ffe0ce051a8 INFO: task syz.4.438:10524 blocked for more than 144 seconds. Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.438 state:D stack:26440 pid:10524 tgid:10475 ppid:8423 task_flags:0x400040 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 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_write_slowpath+0xedd/0x1420 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1e2/0x220 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:902 [inline] filename_create+0x266/0x490 fs/namei.c:4097 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+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efc8058e169 RSP: 002b:00007efc81332038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007efc807b6080 RCX: 00007efc8058e169 RDX: 0000000000000000 RSI: 0000000000000024 RDI: 0000200000001200 RBP: 00007efc80610a68 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007efc807b6080 R15: 00007ffe0ce051a8 INFO: task syz.4.438:10526 blocked for more than 144 seconds. Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.438 state:D stack:27944 pid:10526 tgid:10475 ppid:8423 task_flags:0x400040 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 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_write_slowpath+0xedd/0x1420 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1e2/0x220 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:902 [inline] filename_create+0x266/0x490 fs/namei.c:4097 do_mkdirat+0xbf/0x3f0 fs/namei.c:4349 __do_sys_mkdirat fs/namei.c:4374 [inline] __se_sys_mkdirat fs/namei.c:4372 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4372 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efc8058c9d7 RSP: 002b:00007efc81310e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007efc81310ef0 RCX: 00007efc8058c9d7 RDX: 00000000000001ff RSI: 0000200000000280 RDI: 00000000ffffff9c RBP: 00002000000002c0 R08: 0000200000000000 R09: 0000000000000000 R10: 00002000000002c0 R11: 0000000000000246 R12: 0000200000000280 R13: 00007efc81310eb0 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: #0: ffff8880b8639998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 1 lock held by khungtaskd/31: #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/u8:7/3027: 2 locks held by getty/5585: #0: ffff8880369720a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036db2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 2 locks held by kworker/0:4/5880: 1 lock held by syz-executor/6584: 1 lock held by syz-executor/10206: 6 locks held by syz.4.438/10476: #0: ffff888031978420 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff888031978730 (&type->s_vfs_rename_key#3){+.+.}-{4:4}, at: lock_rename fs/namei.c:3234 [inline] #1: ffff888031978730 (&type->s_vfs_rename_key#3){+.+.}-{4:4}, at: do_renameat2+0x5d6/0x1290 fs/namei.c:5181 #2: ffff888058c0e330 (&sb->s_type->i_mutex_key#26/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #2: ffff888058c0e330 (&sb->s_type->i_mutex_key#26/1){+.+.}-{4:4}, at: lock_two_directories+0x1a8/0x220 fs/namei.c:3210 #3: ffff888058c0d650 (&sb->s_type->i_mutex_key#33/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #3: ffff888058c0d650 (&sb->s_type->i_mutex_key#33/5){+.+.}-{4:4}, at: lock_two_directories+0x1d1/0x220 fs/namei.c:3211 #4: ffff888058c0e9a0 (&sb->s_type->i_mutex_key#33/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #4: ffff888058c0e9a0 (&sb->s_type->i_mutex_key#33/2){+.+.}-{4:4}, at: vfs_rename+0x63f/0xf10 fs/namei.c:5049 #5: ffff888058c0d650 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #5: ffff888058c0d650 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: vfs_rename+0x6b9/0xf10 fs/namei.c:5051 2 locks held by syz.4.438/10524: #0: ffff888031978420 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff888058c0e330 (&sb->s_type->i_mutex_key#26/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #1: ffff888058c0e330 (&sb->s_type->i_mutex_key#26/1){+.+.}-{4:4}, at: filename_create+0x266/0x490 fs/namei.c:4097 2 locks held by syz.4.438/10526: #0: ffff888031978420 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff888058c0e330 (&sb->s_type->i_mutex_key#26/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #1: ffff888058c0e330 (&sb->s_type->i_mutex_key#26/1){+.+.}-{4:4}, at: filename_create+0x266/0x490 fs/namei.c:4097 2 locks held by syz-executor/10770: #0: ffff88802e1840e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802e1840e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802e1840e0 (&type->s_umount_key#63){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8ed43300 (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-00278-gfc96b232f8e7 #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: 69 Comm: kworker/u8:4 Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: kvfree_rcu_reclaim kfree_rcu_work RIP: 0010:__asan_memset+0x27/0x50 mm/kasan/shadow.c:87 Code: 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 d3 41 89 f6 48 89 fd 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 5d e6 ff ff 84 c0 74 12 <48> 89 ef 44 89 f6 48 89 da 5b 41 5e 5d e9 d7 7e fd 09 31 c0 5b 41 RSP: 0018:ffffc900015a74a8 EFLAGS: 00000202 RAX: ffffc900015a7a01 RBX: 0000000000000010 RCX: ffffffff816da656 RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc900015a75f0 RBP: ffffc900015a75f0 R08: ffffc900015a75ff R09: 1ffff920002b4ebf R10: dffffc0000000000 R11: fffff520002b4ec0 R12: ffffc900015a75a0 R13: ffffc900015a8000 R14: 0000000000000000 R15: ffffc900015a0000 FS: 0000000000000000(0000) GS:ffff8881250cf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000000eb38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xb46/0x23b0 arch/x86/kernel/unwind_orc.c:592 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:2398 [inline] slab_free_freelist_hook mm/slub.c:2427 [inline] slab_free_bulk mm/slub.c:4680 [inline] kmem_cache_free_bulk+0x2da/0x530 mm/slub.c:5257 kfree_bulk include/linux/slab.h:794 [inline] kvfree_rcu_bulk+0xd3/0x1d0 mm/slab_common.c:1516 kfree_rcu_work+0xf1/0x170 mm/slab_common.c:1594 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