INFO: task syz.6.545:6936 blocked for more than 143 seconds.
      Not tainted 5.15.178-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.545       state:D stack:25016 pid: 6936 ppid:  5589 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165
 inode_lock include/linux/fs.h:789 [inline]
 open_last_lookups fs/namei.c:3529 [inline]
 path_openat+0x824/0x2f20 fs/namei.c:3739
 do_filp_open+0x21c/0x460 fs/namei.c:3769
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1280
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9542871169
RSP: 002b:00007f95406b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9542a8a080 RCX: 00007f9542871169
RDX: 0000000000143042 RSI: 0000400000000040 RDI: ffffffffffffff9c
RBP: 00007f95428f22a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9542a8a080 R15: 00007fff65835358
 </TASK>
INFO: task syz.6.545:6980 blocked for more than 144 seconds.
      Not tainted 5.15.178-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.545       state:D stack:28512 pid: 6980 ppid:  5589 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 inode_lock_shared include/linux/fs.h:799 [inline]
 lookup_slow+0x45/0x70 fs/namei.c:1679
 walk_component+0x48c/0x610 fs/namei.c:1976
 lookup_last fs/namei.c:2431 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2455
 filename_lookup+0x230/0x5c0 fs/namei.c:2484
 user_path_at_empty+0x40/0x180 fs/namei.c:2883
 user_path_at include/linux/namei.h:57 [inline]
 do_mount fs/namespace.c:3352 [inline]
 __do_sys_mount fs/namespace.c:3563 [inline]
 __se_sys_mount+0x296/0x3c0 fs/namespace.c:3540
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9542871169
RSP: 002b:00007f9540698038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f9542a8a160 RCX: 00007f9542871169
RDX: 00004000000001c0 RSI: 0000400000000180 RDI: 0000000000000000
RBP: 00007f95428f22a0 R08: 0000400000000280 R09: 0000000000000000
R10: 0000000001180000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9542a8a160 R15: 00007fff65835358
 </TASK>

Showing all locks held in the system:
3 locks held by ksoftirqd/0/14:
1 lock held by khungtaskd/27:
 #0: ffffffff8cb1fce0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:1/144:
 #0: ffff8880175cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc900016efd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8dc36b10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xc90 net/core/net_namespace.c:572
 #3: ffffffff8cb241b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:4039
2 locks held by udevd/3544:
 #0: ffff888021587d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x14d/0xa50 block/bdev.c:817
 #1: ffff8880217c4468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_open+0x68/0x100 drivers/block/loop.c:2055
2 locks held by getty/3930:
 #0: ffff88802c850098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025c62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
1 lock held by syz.6.545/6926:
2 locks held by syz.6.545/6936:
 #0: ffff88805dc06460 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377
 #1: ffff888062e506d0 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
 #1: ffff888062e506d0 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: open_last_lookups fs/namei.c:3529 [inline]
 #1: ffff888062e506d0 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: path_openat+0x824/0x2f20 fs/namei.c:3739
1 lock held by syz.6.545/6980:
 #0: ffff888062e506d0 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:799 [inline]
 #0: ffff888062e506d0 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1679
1 lock held by syz-executor/7225:
 #0: ffff8880217c4468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xa9/0xbe0 drivers/block/loop.c:1365
1 lock held by syz-executor/7470:
 #0: ffff8880217c7468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xa9/0xbe0 drivers/block/loop.c:1365
2 locks held by syz.7.897/8425:
 #0: ffff888021586118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912
 #1: ffff8880217c1468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 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: 6926 Comm: syz.6.545 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__kasan_check_read+0x2/0x10 mm/kasan/shadow.c:31
Code: 41 5c 41 5d 41 5e 41 5f 5d c3 48 c7 c7 37 01 3d 8c eb 0a 48 c7 c7 6f 01 3d 8c 4c 89 fe e8 56 b3 73 08 31 db eb d7 cc cc 89 f6 <48> 8b 0c 24 31 d2 e9 63 ef ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01
RSP: 0018:ffffc9000439eeb8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9000f5a3000 RSI: 0000000000000008 RDI: ffffffff8e0a8768
RBP: ffffc9000439eff0 R08: ffffffff818d30a9 R09: fffffbfff2131821
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000873de4
R13: ffffffff818deff5 R14: 00007f9542871169 R15: dffffc0000000000
FS:  00007f95406da6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8fd1c51bac CR3: 00000000520fd000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0xa8/0x9a0 kernel/locking/lockdep.c:5634
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 is_bpf_text_address+0x24f/0x260 kernel/bpf/core.c:727
 kernel_text_address kernel/extable.c:151 [inline]
 __kernel_text_address+0x94/0x100 kernel/extable.c:105
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 alloc_buffer_head+0x20/0xf0 fs/buffer.c:3311
 alloc_page_buffers+0x3a3/0x660 fs/buffer.c:832
 create_empty_buffers+0x3a/0x6d0 fs/buffer.c:1562
 create_page_buffers+0x1d4/0x330 fs/buffer.c:1679
 block_read_full_page+0xe6/0xde0 fs/buffer.c:2270
 do_read_cache_page+0x752/0x1040
 read_mapping_page include/linux/pagemap.h:515 [inline]
 dir_get_page fs/sysv/dir.c:58 [inline]
 sysv_find_entry+0x1b0/0x650 fs/sysv/dir.c:146
 sysv_inode_by_name+0x9e/0x3f0 fs/sysv/dir.c:360
 sysv_lookup+0x63/0xe0 fs/sysv/namei.c:38
 __lookup_slow+0x275/0x3d0 fs/namei.c:1663
 lookup_slow+0x53/0x70 fs/namei.c:1680
 walk_component+0x48c/0x610 fs/namei.c:1976
 lookup_last fs/namei.c:2431 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2455
 filename_lookup+0x230/0x5c0 fs/namei.c:2484
 user_path_at_empty+0x40/0x180 fs/namei.c:2883
 user_path_at include/linux/namei.h:57 [inline]
 do_fchownat+0xec/0x240 fs/open.c:705
 __do_sys_lchown fs/open.c:736 [inline]
 __se_sys_lchown fs/open.c:734 [inline]
 __x64_sys_lchown+0x81/0x90 fs/open.c:734
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9542871169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f95406da038 EFLAGS: 00000246 ORIG_RAX: 000000000000005e
RAX: ffffffffffffffda RBX: 00007f9542a89fa0 RCX: 00007f9542871169
RDX: 00000000ffffffff RSI: 0000000000000000 RDI: 0000400000000000
RBP: 00007f95428f22a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9542a89fa0 R15: 00007fff65835358
 </TASK>