============================================ WARNING: possible recursive locking detected 5.15.159-syzkaller #0 Not tainted -------------------------------------------- syz-executor425/3500 is trying to acquire lock: ffff88801f21b168 (&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: ffff88801f21b168 (&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-executor425/3500: #0: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #1: ffff88801f21b168 (&htab->buckets[i].lock){+...}-{2:2}, at: sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:943 #2: ffff88807c186290 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] #2: ffff88807c186290 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:147 [inline] #2: ffff88807c186290 (&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: 0 PID: 3500 Comm: syz-executor425 Not tainted 5.15.159-syzkaller #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+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/0x84c 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:421 [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/0x84c 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 exit_sem+0x1991/0x1a00 ipc/sem.c:2450 do_exit+0x640/0x2480 kernel/exit.c:865 do_group_exit+0x144/0x310 kernel/exit.c:994 __do_sys_exit_group kernel/exit.c:1005 [inline] __se_sys_exit_group kernel/exit.c:1003 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1003 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: 0033:0x7f754b27f949 Code: Unable to access opcode bytes at RIP 0x7f754b27f91f. RSP: 002b:00007ffdd07303f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f754b27f949 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 00007f754b30b2d0 R08: ffffffffffffffb0 R09: 00007ffdd0730480 R10: 00007ffdd0730480 R11: 0000000000000246 R12: 00007f754b30b2d0 R13: 0000000000000000 R14: 00007f754b30be60 R15: 00007f754b24d760