====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc4-next-20240417-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/24328 is trying to acquire lock: ffff88807cbabbf0 (clock-AF_INET6){++--}-{2:2}, at: sk_psock_drop+0x34/0x500 net/core/skmsg.c:837 but task is already holding lock: ffff88802cf6a068 (&htab->buckets[i].lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88802cf6a068 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:957 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&htab->buckets[i].lock){+.-.}-{2:2}: 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_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:957 0xffffffffa000085a bpf_dispatcher_nop_func include/linux/bpf.h:1233 [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:2392 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2433 __traceiter_kfree+0x2b/0x50 include/trace/events/kmem.h:94 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x2ad/0x350 mm/slub.c:4501 rds_send_remove_from_sock+0x66e/0x800 net/rds/send.c:666 rds_send_path_drop_acked+0x36b/0x3b0 net/rds/send.c:709 rds_tcp_write_space+0x196/0x5f0 net/rds/tcp_send.c:199 tcp_new_space net/ipv4/tcp_input.c:5622 [inline] tcp_check_space+0x65e/0xb00 net/ipv4/tcp_input.c:5641 tcp_data_snd_check net/ipv4/tcp_input.c:5650 [inline] tcp_rcv_established+0x1032/0x2020 net/ipv4/tcp_input.c:6168 tcp_v6_do_rcv+0xa09/0x1300 net/ipv6/tcp_ipv6.c:1647 tcp_v6_rcv+0x24ef/0x2f10 net/ipv6/tcp_ipv6.c:1916 ip6_protocol_deliver_rcu+0xc76/0x1570 net/ipv6/ip6_input.c:438 ip6_input_finish+0x186/0x2d0 net/ipv6/ip6_input.c:483 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5605 [inline] __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5719 process_backlog+0x391/0x7d0 net/core/dev.c:6048 __napi_poll+0xcb/0x490 net/core/dev.c:6702 napi_poll net/core/dev.c:6771 [inline] net_rx_action+0x7bb/0x10a0 net/core/dev.c:6887 __do_softirq+0x2c6/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 inet_wait_for_connect net/ipv4/af_inet.c:611 [inline] __inet_stream_connect+0x8bd/0xf30 net/ipv4/af_inet.c:705 inet_stream_connect+0x65/0xa0 net/ipv4/af_inet.c:750 __sys_connect_file net/socket.c:2048 [inline] __sys_connect+0x2df/0x310 net/socket.c:2065 __do_sys_connect net/socket.c:2075 [inline] __se_sys_connect net/socket.c:2072 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2072 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 -> #0 (clock-AF_INET6){++--}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x35/0x50 kernel/locking/spinlock.c:334 sk_psock_drop+0x34/0x500 net/core/skmsg.c:837 sock_hash_delete_elem+0x392/0x400 net/core/sock_map.c:961 map_delete_elem+0x464/0x5e0 kernel/bpf/syscall.c:1696 __sys_bpf+0x598/0x810 kernel/bpf/syscall.c:5655 __do_sys_bpf kernel/bpf/syscall.c:5771 [inline] __se_sys_bpf kernel/bpf/syscall.c:5769 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5769 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 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&htab->buckets[i].lock); lock(clock-AF_INET6); lock(&htab->buckets[i].lock); lock(clock-AF_INET6); *** DEADLOCK *** 2 locks held by syz-executor.2/24328: #0: ffffffff8e333b60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e333b60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e333b60 (rcu_read_lock){....}-{1:2}, at: map_delete_elem+0x388/0x5e0 kernel/bpf/syscall.c:1695 #1: ffff88802cf6a068 (&htab->buckets[i].lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff88802cf6a068 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:957 stack backtrace: CPU: 1 PID: 24328 Comm: syz-executor.2 Not tainted 6.9.0-rc4-next-20240417-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+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x35/0x50 kernel/locking/spinlock.c:334 sk_psock_drop+0x34/0x500 net/core/skmsg.c:837 sock_hash_delete_elem+0x392/0x400 net/core/sock_map.c:961 map_delete_elem+0x464/0x5e0 kernel/bpf/syscall.c:1696 __sys_bpf+0x598/0x810 kernel/bpf/syscall.c:5655 __do_sys_bpf kernel/bpf/syscall.c:5771 [inline] __se_sys_bpf kernel/bpf/syscall.c:5769 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5769 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: 0033:0x7fb9ae47dea9 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:00007fb9af1840c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fb9ae5abf80 RCX: 00007fb9ae47dea9 RDX: 0000000000000020 RSI: 00000000200015c0 RDI: 0000000000000003 RBP: 00007fb9ae4ca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fb9ae5abf80 R15: 00007ffcf3312898