============================================ WARNING: possible recursive locking detected 6.9.0-rc5-syzkaller-00184-gba1cb99b559e #0 Not tainted -------------------------------------------- syz-executor160/5087 is trying to acquire lock: ffff888022fc9200 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888022fc9200 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:417 [inline] ffff888022fc9200 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:449 but task is already holding lock: ffff88802ae24a00 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88802ae24a00 (&stab->lock){+...}-{2:2}, at: sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:493 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-executor160/5087: #0: ffff88801d377a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1673 [inline] #0: ffff88801d377a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sock_map_sk_acquire net/core/sock_map.c:117 [inline] #0: ffff88801d377a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sock_map_update_elem_sys+0x1cc/0x910 net/core/sock_map.c:578 #1: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #1: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #1: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: sock_map_sk_acquire net/core/sock_map.c:118 [inline] #1: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: sock_map_update_elem_sys+0x1d8/0x910 net/core/sock_map.c:578 #2: ffff88802ae24a00 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #2: ffff88802ae24a00 (&stab->lock){+...}-{2:2}, at: sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:493 #3: ffff88801f046290 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #3: ffff88801f046290 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:145 [inline] #3: ffff88801f046290 (&psock->link_lock){+...}-{2:2}, at: sock_map_unref+0xcc/0x5e0 net/core/sock_map.c:180 #4: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #4: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #4: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #4: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 kernel/trace/bpf_trace.c:2420 stack backtrace: CPU: 0 PID: 5087 Comm: syz-executor160 Not tainted 6.9.0-rc5-syzkaller-00184-gba1cb99b559e #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+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:417 [inline] sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:449 bpf_prog_d284ea97e99fac5b+0x47/0x4b bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x2af/0x3a0 mm/slub.c:4377 sk_psock_free_link include/linux/skmsg.h:421 [inline] sock_map_del_link net/core/sock_map.c:158 [inline] sock_map_unref+0x3ac/0x5e0 net/core/sock_map.c:180 sock_map_update_common+0x4f0/0x5b0 net/core/sock_map.c:506 sock_map_update_elem_sys+0x55f/0x910 net/core/sock_map.c:582 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5648 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765 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: 0033:0x7f570a8d3729 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