============================================ WARNING: possible recursive locking detected 6.12.0-rc3-syzkaller-00454-gdb87114dcf13 #0 Not tainted -------------------------------------------- syz.3.937/8729 is trying to acquire lock: ffffc9002d5090d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 but task is already holding lock: ffffc90023dd50d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&rb->spinlock); lock(&rb->spinlock); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by syz.3.937/8729: #0: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: ieee80211_iterate_active_interfaces_atomic+0x3e/0x1b0 net/mac80211/util.c:809 #1: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #1: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2317 [inline] #1: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run3+0x1d1/0x5a0 kernel/trace/bpf_trace.c:2360 #2: ffffc90023dd50d8 (&rb->spinlock){-.-.}-{2:2}, at: __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 #3: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #3: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2317 [inline] #3: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2359 stack backtrace: CPU: 0 UID: 0 PID: 8729 Comm: syz.3.937 Not tainted 6.12.0-rc3-syzkaller-00454-gdb87114dcf13 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_deadlock_bug+0x2e3/0x410 kernel/locking/lockdep.c:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain kernel/locking/lockdep.c:3891 [inline] __lock_acquire+0x2185/0x3ce0 kernel/locking/lockdep.c:5202 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 ____bpf_ringbuf_reserve kernel/bpf/ringbuf.c:478 [inline] bpf_ringbuf_reserve+0x57/0x90 kernel/bpf/ringbuf.c:470 bpf_prog_0e153dac479590bf+0x35/0x70 bpf_dispatcher_nop_func include/linux/bpf.h:1257 [inline] __bpf_prog_run include/linux/filter.h:701 [inline] bpf_prog_run include/linux/filter.h:708 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2318 [inline] bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2359 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:94 [inline] trace_contention_begin.constprop.0+0xed/0x170 include/trace/events/lock.h:95 __pv_queued_spin_lock_slowpath+0x10b/0xc90 kernel/locking/qspinlock.c:402 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x210/0x2c0 kernel/locking/spinlock_debug.c:116 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162 __bpf_ringbuf_reserve+0x36e/0x4b0 kernel/bpf/ringbuf.c:427 ____bpf_ringbuf_reserve kernel/bpf/ringbuf.c:478 [inline] bpf_ringbuf_reserve+0x57/0x90 kernel/bpf/ringbuf.c:470 bpf_prog_fe0ed97373b08409+0x2e/0x4b bpf_dispatcher_nop_func include/linux/bpf.h:1257 [inline] __bpf_prog_run include/linux/filter.h:701 [inline] bpf_prog_run include/linux/filter.h:708 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2318 [inline] bpf_trace_run3+0x240/0x5a0 kernel/trace/bpf_trace.c:2360 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline] kmem_cache_free+0x200/0x4b0 mm/slub.c:4680 kfree_skbmem+0x1a4/0x1f0 net/core/skbuff.c:1148 __kfree_skb net/core/skbuff.c:1205 [inline] consume_skb net/core/skbuff.c:1436 [inline] consume_skb+0xcc/0x100 net/core/skbuff.c:1430 mac80211_hwsim_tx_frame+0x1f3/0x2a0 drivers/net/wireless/virtual/mac80211_hwsim.c:2216 __mac80211_hwsim_beacon_tx drivers/net/wireless/virtual/mac80211_hwsim.c:2232 [inline] mac80211_hwsim_beacon_tx+0x592/0xa00 drivers/net/wireless/virtual/mac80211_hwsim.c:2315 __iterate_interfaces+0x2d0/0x5d0 net/mac80211/util.c:774 ieee80211_iterate_active_interfaces_atomic+0x71/0x1b0 net/mac80211/util.c:810 mac80211_hwsim_beacon+0x105/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2345 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1755 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1772 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:exit_to_user_mode_loop kernel/entry/common.c:101 [inline] RIP: 0010:exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] RIP: 0010:irqentry_exit_to_user_mode+0x120/0x280 kernel/entry/common.c:231 Code: 9c 58 fa f6 c4 02 0f 85 18 01 00 00 e8 69 0e 00 00 48 8b 5d 00 f7 c3 0e 30 02 00 0f 84 2b ff ff ff e8 14 c8 80 f6 fb f6 c3 08 <75> bd f6 c7 10 74 c2 4c 89 e7 e8 d1 03 ac f6 f7 c3 04 00 02 00 74 RSP: 0000:ffffc9000439ff38 EFLAGS: 00000202 RAX: 000000000000596d RBX: 0000000020000008 RCX: 1ffffffff2039471 RDX: 0000000000000000 RSI: ffffffff8b4cc960 RDI: ffffffff8bb12da0 RBP: ffff888023ddc880 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff901ce5cf R11: 0000000000000000 R12: ffffc9000439ff58 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0023:0xf717fbd9 Code: 10 89 74 24 14 8d 74 26 00 8b 45 08 8b 4d 0c 83 c5 08 89 ce 39 d0 19 fe 72 ef 89 44 24 0c 8b 44 24 10 89 4c 24 10 8b 74 24 14 <83> e8 08 89 f9 39 f2 19 d9 73 15 8d 74 26 00 8b 70 f8 8b 58 fc 83 RSP: 002b:00000000ffab6e10 EFLAGS: 00000246 RAX: 00000000f6d0f788 RBX: 00000000ffffffff RCX: 0000000000000000 RDX: 0000000088e461bd RSI: 0000000088e461bd RDI: 00000000ffffffff RBP: 00000000f6d0f670 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 9c pushf 1: 58 pop %rax 2: fa cli 3: f6 c4 02 test $0x2,%ah 6: 0f 85 18 01 00 00 jne 0x124 c: e8 69 0e 00 00 call 0xe7a 11: 48 8b 5d 00 mov 0x0(%rbp),%rbx 15: f7 c3 0e 30 02 00 test $0x2300e,%ebx 1b: 0f 84 2b ff ff ff je 0xffffff4c 21: e8 14 c8 80 f6 call 0xf680c83a 26: fb sti 27: f6 c3 08 test $0x8,%bl * 2a: 75 bd jne 0xffffffe9 <-- trapping instruction 2c: f6 c7 10 test $0x10,%bh 2f: 74 c2 je 0xfffffff3 31: 4c 89 e7 mov %r12,%rdi 34: e8 d1 03 ac f6 call 0xf6ac040a 39: f7 c3 04 00 02 00 test $0x20004,%ebx 3f: 74 .byte 0x74