============================================ WARNING: possible recursive locking detected 5.15.157-syzkaller #0 Not tainted -------------------------------------------- swapper/0/0 is trying to acquire lock: ffff888024606868 (&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: ffff888024606868 (&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 5 locks held by swapper/0/0: #0: ffffffff8c91fbe0 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x0/0x20 #1: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #2: ffff888024606868 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x177/0x400 net/core/sock_map.c:943 #3: ffff8880792e9290 (&psock->link_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] #3: ffff8880792e9290 (&psock->link_lock){+.-.}-{2:2}, at: sock_map_del_link net/core/sock_map.c:147 [inline] #3: ffff8880792e9290 (&psock->link_lock){+.-.}-{2:2}, at: sock_map_unref+0xcc/0x5d0 net/core/sock_map.c:182 #4: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.157-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/0xd60 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/0xd60 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 security_cred_free+0xb2/0xf0 security/security.c:1719 put_cred_rcu+0xd9/0x410 kernel/cred.c:115 rcu_do_batch kernel/rcu/tree.c:2523 [inline] rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2763 __do_softirq+0x3b3/0x93a kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:110 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570 Code: 1d 59 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 44 99 5f f7 0f 1f 44 00 00 e8 3a 19 59 f7 0f 00 2d b3 d8 bb 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 ab f1 a2 f7 RSP: 0018:ffffffff8c607b80 EFLAGS: 000002d3 RAX: ffffffff8a2743a6 RBX: 0000000000000000 RCX: ffffffff8c6bd5c0 RDX: 0000000000000000 RSI: ffffffff8a8b2980 RDI: ffffffff8ad8f500 RBP: ffffffff8c607c10 R08: ffffffff8186dd10 R09: fffffbfff18d7ab9 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff18c0f70 R13: ffff888018e0b804 R14: ffffffff8c607ba0 R15: dffffc0000000000 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:705 cpuidle_enter_state+0x521/0xef0 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3e4/0x670 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_kernel+0x48c/0x540 init/main.c:1140 secondary_startup_64_no_verify+0xb1/0xbb ---------------- Code disassembly (best guess): 0: 1d 59 f7 48 83 sbb $0x8348f759,%eax 5: e3 08 jrcxz 0xf 7: 0f 85 0a 01 00 00 jne 0x117 d: 4c 8d 74 24 20 lea 0x20(%rsp),%r14 12: e8 44 99 5f f7 call 0xf75f995b 17: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 1c: e8 3a 19 59 f7 call 0xf759195b 21: 0f 00 2d b3 d8 bb 00 verw 0xbbd8b3(%rip) # 0xbbd8db 28: fb sti 29: f4 hlt * 2a: 4c 89 f3 mov %r14,%rbx <-- trapping instruction 2d: 48 c1 eb 03 shr $0x3,%rbx 31: 42 80 3c 3b 00 cmpb $0x0,(%rbx,%r15,1) 36: 74 08 je 0x40 38: 4c 89 f7 mov %r14,%rdi 3b: e8 ab f1 a2 f7 call 0xf7a2f1eb