============================================ WARNING: possible recursive locking detected 5.15.158-syzkaller #0 Not tainted -------------------------------------------- udevd/3829 is trying to acquire lock: ffff888017e771c0 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:419 [inline] ffff888017e771c0 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x161/0x230 net/core/sock_map.c:451 but task is already holding lock: ffff888017e771c0 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:419 [inline] ffff888017e771c0 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x161/0x230 net/core/sock_map.c:451 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&stab->lock); lock(&stab->lock); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by udevd/3829: #0: ffffffff8cea9538 (tomoyo_ss){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #1: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #2: ffff888017e771c0 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:419 [inline] #2: ffff888017e771c0 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x161/0x230 net/core/sock_map.c:451 #3: ffff88805f39f290 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] #3: ffff88805f39f290 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:147 [inline] #3: ffff88805f39f290 (&psock->link_lock){+...}-{2:2}, at: sock_map_unref+0xcc/0x5d0 net/core/sock_map.c:182 #4: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 0 PID: 3829 Comm: udevd Not tainted 5.15.158-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2946 [inline] check_deadlock kernel/locking/lockdep.c:2989 [inline] validate_chain+0x46d2/0x5930 kernel/locking/lockdep.c:3775 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 __sock_map_delete net/core/sock_map.c:419 [inline] sock_map_delete_elem+0x161/0x230 net/core/sock_map.c:451 bpf_prog_2c29ac5cdc6b1842+0x3a/0xde0 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:118 __traceiter_kfree+0x26/0x40 include/trace/events/kmem.h:118 trace_kfree include/trace/events/kmem.h:118 [inline] kfree+0x22f/0x270 mm/slub.c:4549 sk_psock_free_link include/linux/skmsg.h:422 [inline] sock_map_del_link net/core/sock_map.c:160 [inline] sock_map_unref+0x3ac/0x5d0 net/core/sock_map.c:182 __sock_map_delete net/core/sock_map.c:425 [inline] sock_map_delete_elem+0x191/0x230 net/core/sock_map.c:451 bpf_prog_2c29ac5cdc6b1842+0x3a/0xde0 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:118 __traceiter_kfree+0x26/0x40 include/trace/events/kmem.h:118 trace_kfree include/trace/events/kmem.h:118 [inline] kfree+0x22f/0x270 mm/slub.c:4549 tomoyo_realpath_from_path+0xcb/0x5e0 security/tomoyo/realpath.c:253 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x22c/0x490 security/tomoyo/file.c:771 security_file_open+0x5f/0xa0 security/security.c:1668 do_dentry_open+0x315/0xfb0 fs/open.c:813 do_open fs/namei.c:3608 [inline] path_openat+0x2705/0x2f20 fs/namei.c:3742 do_filp_open+0x21c/0x460 fs/namei.c:3769 do_sys_openat2+0x13b/0x500 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: 0033:0x7f9470b849a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffec0715480 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000558777acfea0 RCX: 00007f9470b849a4 RDX: 0000000000080000 RSI: 00007ffec0715598 RDI: 00000000ffffff9c RBP: 00007ffec0715598 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 0000558777acff90 R14: 00007ffec0715598 R15: 0000558776e6ca04