syzbot

============================================
WARNING: possible recursive locking detected
6.1.90-syzkaller #0 Not tainted
--------------------------------------------
syz-executor415/3555 is trying to acquire lock:
ffff8881447cb968 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:938

but task is already holding lock:
ffff8881447cbb68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:938

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&htab->buckets[i].lock);
  lock(&htab->buckets[i].lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

4 locks held by syz-executor415/3555:
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2272 [inline]
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x110/0x410 kernel/trace/bpf_trace.c:2312
 #1: ffff8881447cbb68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:938
 #2: ffff888018ae9290 (&psock->link_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
 #2: ffff888018ae9290 (&psock->link_lock){+.-.}-{2:2}, at: sock_map_del_link net/core/sock_map.c:147 [inline]
 #2: ffff888018ae9290 (&psock->link_lock){+.-.}-{2:2}, at: sock_map_unref+0xcc/0x5d0 net/core/sock_map.c:182
 #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2272 [inline]
 #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x110/0x410 kernel/trace/bpf_trace.c:2312

stack backtrace:
CPU: 1 PID: 3555 Comm: syz-executor415 Not tainted 6.1.90-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2983 [inline]
 check_deadlock kernel/locking/lockdep.c:3026 [inline]
 validate_chain+0x4711/0x5950 kernel/locking/lockdep.c:3812
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
 _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:938
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x3e
 bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline]
 bpf_trace_run2+0x1fd/0x410 kernel/trace/bpf_trace.c:2312
 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:94
 __traceiter_kfree+0x26/0x40 include/trace/events/kmem.h:94
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0xf6/0x190 mm/slab_common.c:994
 sk_psock_free_link include/linux/skmsg.h:416 [inline]
 sock_map_del_link net/core/sock_map.c:160 [inline]
 sock_map_unref+0x3ac/0x5d0 net/core/sock_map.c:182
 sock_hash_delete_elem+0x388/0x400 net/core/sock_map.c:942
 </TASK>