============================================ WARNING: possible recursive locking detected 6.9.0-rc5-syzkaller-00185-g3e9bc0472b91 #0 Not tainted -------------------------------------------- syz-executor209/5095 is trying to acquire lock: ffff8880231fba00 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff8880231fba00 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:417 [inline] ffff8880231fba00 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:449 but task is already holding lock: ffff88802ffc7a00 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88802ffc7a00 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:417 [inline] ffff88802ffc7a00 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:449 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-executor209/5095: #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 kernel/trace/bpf_trace.c:2420 #1: ffff88802ffc7a00 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff88802ffc7a00 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:417 [inline] #1: ffff88802ffc7a00 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:449 #2: ffff888075c88290 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #2: ffff888075c88290 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:145 [inline] #2: ffff888075c88290 (&psock->link_lock){+...}-{2:2}, at: sock_map_unref+0xcc/0x5e0 net/core/sock_map.c:180 #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 kernel/trace/bpf_trace.c:2420 stack backtrace: CPU: 0 PID: 5095 Comm: syz-executor209 Not tainted 6.9.0-rc5-syzkaller-00185-g3e9bc0472b91 #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_2c29ac5cdc6b1842+0x42/0x46 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 __traceiter_kfree+0x2b/0x50 include/trace/events/kmem.h:94 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_delete net/core/sock_map.c:423 [inline] sock_map_delete_elem+0x1a2/0x250 net/core/sock_map.c:449 bpf_prog_2c29ac5cdc6b1842+0x42/0x46 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 __traceiter_kfree+0x2b/0x50 include/trace/events/kmem.h:94 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x2af/0x3a0 mm/slub.c:4377 map_update_elem+0x5ca/0x6f0 kernel/bpf/syscall.c:1645 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5653 __do_sys_bpf kernel/bpf/syscall.c:5772 [inline] __se_sys_bpf kernel/bpf/syscall.c:5770 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5770 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: 0033:0x7f67b16d8ee9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff6bad0948 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f67b16d8ee9 RDX: 0000000000000020 RSI: 0000000020000500 RDI: 0000000000000002 RBP: 0000000000000000 R08: 00000000000000a0 R09: 00000000000000a0 R10: 00000000000000a0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000