============================================ WARNING: possible recursive locking detected 6.9.0-syzkaller-08544-g4b377b4868ef #0 Not tainted -------------------------------------------- syz-executor.4/20502 is trying to acquire lock: ffff8880611ada20 (&stab->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff8880611ada20 (&stab->lock){+.-.}-{2:2}, at: __sock_map_delete+0x43/0xe0 net/core/sock_map.c:429 but task is already holding lock: ffff8880611ad220 (&stab->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff8880611ad220 (&stab->lock){+.-.}-{2:2}, at: __sock_map_delete+0x43/0xe0 net/core/sock_map.c:429 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 4 locks held by syz-executor.4/20502: #0: ffffffff8dbb1760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8dbb1760 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8dbb1760 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #0: ffffffff8dbb1760 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2444 #1: ffff8880611ad220 (&stab->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff8880611ad220 (&stab->lock){+.-.}-{2:2}, at: __sock_map_delete+0x43/0xe0 net/core/sock_map.c:429 #2: ffff8880228d72b0 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #2: ffff8880228d72b0 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:157 [inline] #2: ffff8880228d72b0 (&psock->link_lock){+...}-{2:2}, at: sock_map_unref+0xbf/0x6e0 net/core/sock_map.c:192 #3: ffffffff8dbb1760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #3: ffffffff8dbb1760 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #3: ffffffff8dbb1760 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #3: ffffffff8dbb1760 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2444 stack backtrace: CPU: 1 PID: 20502 Comm: syz-executor.4 Not tainted 6.9.0-syzkaller-08544-g4b377b4868ef #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+0x116/0x1f0 lib/dump_stack.c:114 check_deadlock kernel/locking/lockdep.c:3062 [inline] validate_chain kernel/locking/lockdep.c:3856 [inline] __lock_acquire+0x20e6/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] __sock_map_delete+0x43/0xe0 net/core/sock_map.c:429 sock_map_delete_elem+0xb5/0x100 net/core/sock_map.c:461 ___bpf_prog_run+0x3e51/0xabd0 kernel/bpf/core.c:2012 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2253 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+0x231/0x590 kernel/trace/bpf_trace.c:2444 __traceiter_kfree+0x2d/0x50 include/trace/events/kmem.h:94 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x225/0x3a0 mm/slub.c:4450 sk_psock_free_link include/linux/skmsg.h:425 [inline] sock_map_del_link net/core/sock_map.c:170 [inline] sock_map_unref+0x392/0x6e0 net/core/sock_map.c:192 __sock_map_delete+0x88/0xe0 net/core/sock_map.c:435 sock_map_delete_elem+0xb5/0x100 net/core/sock_map.c:461 ___bpf_prog_run+0x3e51/0xabd0 kernel/bpf/core.c:2012 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2253 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+0x231/0x590 kernel/trace/bpf_trace.c:2444 __traceiter_kfree+0x2d/0x50 include/trace/events/kmem.h:94 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x225/0x3a0 mm/slub.c:4450 kvfree+0x47/0x50 mm/util.c:680 map_update_elem+0x68a/0x910 kernel/bpf/syscall.c:1658 __sys_bpf+0xac0/0x4b70 kernel/bpf/syscall.c:5675 __do_sys_bpf kernel/bpf/syscall.c:5794 [inline] __se_sys_bpf kernel/bpf/syscall.c:5792 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5792 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f433847cee9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f43390fc0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f43385abf80 RCX: 00007f433847cee9 RDX: 0000000000000020 RSI: 0000000020000500 RDI: 0000000000000002 RBP: 00007f43384c949e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f43385abf80 R15: 00007ffd3a978028 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.4'.