============================================ WARNING: possible recursive locking detected 6.9.0-rc5-syzkaller-01536-gba39486d2c43 #0 Not tainted -------------------------------------------- syz-executor408/5082 is trying to acquire lock: ffff8880221bda20 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff8880221bda20 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:429 [inline] ffff8880221bda20 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:461 but task is already holding lock: ffff8880221bf220 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff8880221bf220 (&stab->lock){+...}-{2:2}, at: sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:505 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 syz-executor408/5082: #0: ffff888079889a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1673 [inline] #0: ffff888079889a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sock_map_sk_acquire net/core/sock_map.c:129 [inline] #0: ffff888079889a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sock_map_update_elem_sys+0x1cc/0x910 net/core/sock_map.c:590 #1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: sock_map_sk_acquire net/core/sock_map.c:130 [inline] #1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: sock_map_update_elem_sys+0x1d8/0x910 net/core/sock_map.c:590 #2: ffff8880221bf220 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #2: ffff8880221bf220 (&stab->lock){+...}-{2:2}, at: sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:505 #3: ffff88807ce142b0 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #3: ffff88807ce142b0 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:157 [inline] #3: ffff88807ce142b0 (&psock->link_lock){+...}-{2:2}, at: sock_map_unref+0xcc/0x5e0 net/core/sock_map.c:192 #4: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #4: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #4: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #4: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1fc/0x540 kernel/trace/bpf_trace.c:2444 stack backtrace: CPU: 0 PID: 5082 Comm: syz-executor408 Not tainted 6.9.0-rc5-syzkaller-01536-gba39486d2c43 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_deadlock kernel/locking/lockdep.c:3062 [inline] validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] __sock_map_delete net/core/sock_map.c:429 [inline] sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:461 bpf_prog_d284ea97e99fac5b+0x47/0x4b bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2444 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x2af/0x3a0 mm/slub.c:4377 sk_psock_free_link include/linux/skmsg.h:425 [inline] sock_map_del_link net/core/sock_map.c:170 [inline] sock_map_unref+0x3ac/0x5e0 net/core/sock_map.c:192 sock_map_update_common+0x4f0/0x5b0 net/core/sock_map.c:518 sock_map_update_elem_sys+0x55f/0x910 net/core/sock_map.c:594 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1654 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5670 __do_sys_bpf kernel/bpf/syscall.c:5789 [inline] __se_sys_bpf kernel/bpf/syscall.c:5787 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5787 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7246bc7729 Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffceebff9b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007ffceebffb88 RCX: 00007f7246bc7729 RDX: 0000000000000020 RSI: 0000000020000680 RDI: 0000000000000002 RBP: 00007f7246c3a610 R08: 00007ffceebffb88 R09: 00007ffceebffb88 R10: 00007ffceebffb88 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffceebffb78 R14: 00