============================================ WARNING: possible recursive locking detected 5.15.158-syzkaller #0 Not tainted -------------------------------------------- syz-executor.1/5434 is trying to acquire lock: ffff88801de68668 (&htab->buckets[i].lock){+...}-{2:2}, at: sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:943 but task is already holding lock: ffff88801de68668 (&htab->buckets[i].lock){+...}-{2:2}, at: sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:943 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-executor.1/5434: #0: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #1: ffff88801de68668 (&htab->buckets[i].lock){+...}-{2:2}, at: sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:943 #2: ffff88801a2fc290 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] #2: ffff88801a2fc290 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:147 [inline] #2: ffff88801a2fc290 (&psock->link_lock){+...}-{2:2}, at: sock_map_unref+0xcc/0x5d0 net/core/sock_map.c:182 #3: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 1 PID: 5434 Comm: syz-executor.1 Not tainted 5.15.158-syzkaller #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+0x1e3/0x2d0 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2946 [inline] check_deadlock kernel/locking/lockdep.c:2989 [inline] validate_chain+0x46d2/0x5930 kernel/locking/lockdep.c:3775 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:943 bpf_prog_2c29ac5cdc6b1842+0x3a/0xed8 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:118 trace_kfree include/trace/events/kmem.h:118 [inline] kfree+0x22f/0x270 mm/slub.c:4549 sk_psock_free_link include/linux/skmsg.h:422 [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:947 bpf_prog_2c29ac5cdc6b1842+0x3a/0xed8 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:118 trace_kfree include/trace/events/kmem.h:118 [inline] kfree+0x22f/0x270 mm/slub.c:4549 xt_free_table_info+0xcb/0x190 net/netfilter/x_tables.c:1208 __do_replace+0x81e/0xad0 net/ipv4/netfilter/ip_tables.c:1085 do_replace net/ipv4/netfilter/ip_tables.c:1142 [inline] do_ipt_set_ctl+0xe8b/0x1200 net/ipv4/netfilter/ip_tables.c:1636 nf_setsockopt+0x28a/0x2b0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0x2732/0x3fb0 net/ipv4/ip_sockglue.c:1442 tcp_setsockopt+0x23f/0x3680 net/ipv4/tcp.c:3707 __sys_setsockopt+0x57e/0x990 net/socket.c:2198 __do_sys_setsockopt net/socket.c:2209 [inline] __se_sys_setsockopt net/socket.c:2206 [inline] __x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2206 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f02ece8aa7a Code: ff ff ff c3 0f 1f 40 00 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 49 89 ca b8 36 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 b0 ff ff ff f7 RSP: 002b:00007fffd00cfa88 EFLAGS: 00000202 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007fffd00cfb10 RCX: 00007f02ece8aa7a RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00000000000002d8 R09: 00007fffd00cfec7 R10: 00007f02ecf87d60 R11: 0000000000000202 R12: 00007f02ecf87d00 R13: 00007fffd00cfaac R14: 0000000000000000 R15: 00007f02ecf89ec0