====================================================== WARNING: possible circular locking dependency detected 6.8.0-syzkaller-05271-gf99c5f563c17 #0 Not tainted ------------------------------------------------------ syz-executor.4/21902 is trying to acquire lock: ffff88804ec83bf0 (clock-AF_UNIX){++..}-{2:2}, at: sock_map_del_link net/core/sock_map.c:163 [inline] ffff88804ec83bf0 (clock-AF_UNIX){++..}-{2:2}, at: sock_map_unref+0x442/0x5e0 net/core/sock_map.c:180 but task is already holding lock: ffff888066451200 (&stab->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888066451200 (&stab->lock){+.-.}-{2:2}, at: sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:490 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&stab->lock){+.-.}-{2:2}: lock_acquire+0x1e4/0x530 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:414 [inline] sock_map_delete_elem+0x97/0x140 net/core/sock_map.c:446 0xffffffffa00048e6 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+0x291/0x380 mm/slub.c:4396 __bpf_prog_put_noref+0xd7/0x310 kernel/bpf/syscall.c:2244 bpf_prog_put_deferred+0x2f3/0x3e0 kernel/bpf/syscall.c:2270 __bpf_prog_put kernel/bpf/syscall.c:2282 [inline] bpf_prog_put+0x264/0x2a0 kernel/bpf/syscall.c:2289 psock_set_prog include/linux/skmsg.h:475 [inline] sk_psock_stop_strp net/core/skmsg.c:1156 [inline] sk_psock_drop+0xe0/0x500 net/core/skmsg.c:841 sk_psock_put include/linux/skmsg.h:459 [inline] sock_map_close+0x209/0x2d0 net/core/sock_map.c:1648 unix_release+0x85/0xc0 net/unix/af_unix.c:1048 __sock_release net/socket.c:659 [inline] sock_close+0xbc/0x240 net/socket.c:1421 __fput+0x429/0x8a0 fs/file_table.c:423 __do_sys_close fs/open.c:1557 [inline] __se_sys_close fs/open.c:1542 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1542 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> #0 (clock-AF_UNIX){++..}-{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+0x1e4/0x530 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 sock_map_del_link net/core/sock_map.c:163 [inline] sock_map_unref+0x442/0x5e0 net/core/sock_map.c:180 sock_map_update_common+0x4f0/0x5b0 net/core/sock_map.c:503 sock_map_update_elem_sys+0x55f/0x910 net/core/sock_map.c:579 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5619 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&stab->lock); lock(clock-AF_UNIX); lock(&stab->lock); lock(clock-AF_UNIX); *** DEADLOCK *** 3 locks held by syz-executor.4/21902: #0: ffff88804ec85a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1671 [inline] #0: ffff88804ec85a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sock_map_sk_acquire net/core/sock_map.c:117 [inline] #0: ffff88804ec85a58 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sock_map_update_elem_sys+0x1cc/0x910 net/core/sock_map.c:575 #1: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #1: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #1: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: sock_map_sk_acquire net/core/sock_map.c:118 [inline] #1: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: sock_map_update_elem_sys+0x1d8/0x910 net/core/sock_map.c:575 #2: ffff888066451200 (&stab->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #2: ffff888066451200 (&stab->lock){+.-.}-{2:2}, at: sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:490 stack backtrace: CPU: 1 PID: 21902 Comm: syz-executor.4 Not tainted 6.8.0-syzkaller-05271-gf99c5f563c17 #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+0x1e7/0x2e0 lib/dump_stack.c:106 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+0x1e4/0x530 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 sock_map_del_link net/core/sock_map.c:163 [inline] sock_map_unref+0x442/0x5e0 net/core/sock_map.c:180 sock_map_update_common+0x4f0/0x5b0 net/core/sock_map.c:503 sock_map_update_elem_sys+0x55f/0x910 net/core/sock_map.c:579 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5619 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f9934c7de69 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:00007f9935a7c0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f9934dac120 RCX: 00007f9934c7de69 RDX: 0000000000000020 RSI: 0000000020000880 RDI: 0000000000000002 RBP: 00007f9934cca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f9934dac120 R15: 00007fffdd7d6668