============================================ WARNING: possible recursive locking detected 5.19.0-rc6-syzkaller-00296-g11052589cf5c #0 Not tainted -------------------------------------------- syz-executor.5/3628 is trying to acquire lock: ffff88805c21d458 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] ffff88805c21d458 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4256 [inline] ffff88805c21d458 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x318/0xbe0 net/sched/sch_generic.c:340 but task is already holding lock: ffff888078fd6cd8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] ffff888078fd6cd8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4256 [inline] ffff888078fd6cd8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x318/0xbe0 net/sched/sch_generic.c:340 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(_xmit_ETHER#2); lock(_xmit_ETHER#2); *** DEADLOCK *** May be due to missing lock nesting notation 8 locks held by syz-executor.5/3628: #0: ffffc900001e0d70 ((&in_dev->mr_ifc_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:31 [inline] #0: ffffc900001e0d70 ((&in_dev->mr_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 kernel/time/timer.c:1464 #1: ffffffff8bd87040 (rcu_read_lock_bh){....}-{1:2}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:95 [inline] #1: ffffffff8bd87040 (rcu_read_lock_bh){....}-{1:2}, at: ip_finish_output2+0x292/0x2170 net/ipv4/ip_output.c:214 #2: ffffffff8bd87040 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1e3/0x3900 net/core/dev.c:4172 #3: ffff888025b23258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:359 [inline] #3: ffff888025b23258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:187 [inline] #3: ffff888025b23258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:184 [inline] #3: ffff888025b23258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3804 [inline] #3: ffff888025b23258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1274/0x3900 net/core/dev.c:4221 #4: ffff888078fd6cd8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] #4: ffff888078fd6cd8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4256 [inline] #4: ffff888078fd6cd8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x318/0xbe0 net/sched/sch_generic.c:340 #5: ffffffff8bd87040 (rcu_read_lock_bh){....}-{1:2}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:95 [inline] #5: ffffffff8bd87040 (rcu_read_lock_bh){....}-{1:2}, at: ip_finish_output2+0x292/0x2170 net/ipv4/ip_output.c:214 #6: ffffffff8bd87040 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1e3/0x3900 net/core/dev.c:4172 #7: ffff88805c351258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:359 [inline] #7: ffff88805c351258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:187 [inline] #7: ffff88805c351258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:184 [inline] #7: ffff88805c351258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3804 [inline] #7: ffff88805c351258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1274/0x3900 net/core/dev.c:4221 stack backtrace: CPU: 1 PID: 3628 Comm: syz-executor.5 Not tainted 5.19.0-rc6-syzkaller-00296-g11052589cf5c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2988 [inline] check_deadlock kernel/locking/lockdep.c:3031 [inline] validate_chain kernel/locking/lockdep.c:3816 [inline] __lock_acquire.cold+0x1f5/0x3b4 kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5630 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:349 [inline] __netif_tx_lock include/linux/netdevice.h:4256 [inline] sch_direct_xmit+0x318/0xbe0 net/sched/sch_generic.c:340 __dev_xmit_skb net/core/dev.c:3817 [inline] __dev_queue_xmit+0x14a1/0x3900 net/core/dev.c:4221 dev_queue_xmit include/linux/netdevice.h:2994 [inline] neigh_resolve_output net/core/neighbour.c:1528 [inline] neigh_resolve_output+0x517/0x840 net/core/neighbour.c:1508 neigh_output include/net/neighbour.h:549 [inline] ip_finish_output2+0x782/0x2170 net/ipv4/ip_output.c:228 __ip_finish_output net/ipv4/ip_output.c:306 [inline] __ip_finish_output+0x396/0x650 net/ipv4/ip_output.c:288 ip_finish_output+0x32/0x280 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip_output+0x19f/0x310 net/ipv4/ip_output.c:430 dst_output include/net/dst.h:451 [inline] ip_local_out+0xaf/0x1a0 net/ipv4/ip_output.c:126 iptunnel_xmit+0x67a/0xa40 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x10f0/0x2c00 net/ipv4/ip_tunnel.c:811 erspan_xmit+0x81d/0x2790 net/ipv4/ip_gre.c:715 __netdev_start_xmit include/linux/netdevice.h:4805 [inline] netdev_start_xmit include/linux/netdevice.h:4819 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x188/0x880 net/core/dev.c:3606 sch_direct_xmit+0x19f/0xbe0 net/sched/sch_generic.c:342 __dev_xmit_skb net/core/dev.c:3817 [inline] __dev_queue_xmit+0x14a1/0x3900 net/core/dev.c:4221 dev_queue_xmit include/linux/netdevice.h:2994 [inline] neigh_resolve_output net/core/neighbour.c:1528 [inline] neigh_resolve_output+0x517/0x840 net/core/neighbour.c:1508 neigh_output include/net/neighbour.h:549 [inline] ip_finish_output2+0x782/0x2170 net/ipv4/ip_output.c:228 __ip_finish_output net/ipv4/ip_output.c:306 [inline] __ip_finish_output+0x396/0x650 net/ipv4/ip_output.c:288 ip_finish_output+0x32/0x280 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip_output+0x19f/0x310 net/ipv4/ip_output.c:430 dst_output include/net/dst.h:451 [inline] ip_local_out+0xaf/0x1a0 net/ipv4/ip_output.c:126 igmpv3_send_cr net/ipv4/igmp.c:719 [inline] igmp_ifc_timer_expire+0x75b/0xf80 net/ipv4/igmp.c:808 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers.part.0+0x679/0xa80 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803 __do_softirq+0x29b/0x9c2 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:finish_task_switch.isra.0+0x2b9/0xbb0 kernel/sched/core.c:5026 Code: 8b 3b 4c 89 f7 48 c7 03 00 00 00 00 ff d2 4d 85 ff 75 bd 4c 89 f7 e8 66 f8 ff ff e8 f1 64 2e 00 fb 65 48 8b 1c 25 80 6f 02 00 <48> 8d bb 80 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 RSP: 0018:ffffc9000320fad0 EFLAGS: 00000206 RAX: 00000000038c4f2b RBX: ffff888022f50000 RCX: 1ffffffff1b76f99 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000320fb18 R08: 0000000000000001 R09: 0000000000000001 R10: ffffed10173673d8 R11: 0000000000000001 R12: ffff8880b9b3ac18 R13: ffff88807f758000 R14: ffff8880b9b39ec0 R15: ffff8880b9b3a8f8 context_switch kernel/sched/core.c:5149 [inline] __schedule+0xa08/0x4b50 kernel/sched/core.c:6458 schedule+0xd2/0x1f0 kernel/sched/core.c:6530 freezable_schedule include/linux/freezer.h:172 [inline] do_nanosleep+0x24e/0x690 kernel/time/hrtimer.c:2044 hrtimer_nanosleep+0x1f9/0x4a0 kernel/time/hrtimer.c:2097 common_nsleep+0xa2/0xc0 kernel/time/posix-timers.c:1236 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1276 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1254 [inline] __x64_sys_clock_nanosleep+0x2f4/0x430 kernel/time/posix-timers.c:1254 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f4e8beadec1 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 aa e7 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 e3 e7 ff ff 48 8b 04 24 eb 97 66 2e 0f 1f RSP: 002b:00007ffcb4c378d0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 00000000000002db RCX: 00007f4e8beadec1 RDX: 00007ffcb4c37910 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffcb4c3799c R08: 0000000000000000 R09: 00007ffcb4d57080 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 000000000020a0c3 R14: 0000000000000000 R15: 00007ffcb4c37a00 ---------------- Code disassembly (best guess): 0: 8b 3b mov (%rbx),%edi 2: 4c 89 f7 mov %r14,%rdi 5: 48 c7 03 00 00 00 00 movq $0x0,(%rbx) c: ff d2 callq *%rdx e: 4d 85 ff test %r15,%r15 11: 75 bd jne 0xffffffd0 13: 4c 89 f7 mov %r14,%rdi 16: e8 66 f8 ff ff callq 0xfffff881 1b: e8 f1 64 2e 00 callq 0x2e6511 20: fb sti 21: 65 48 8b 1c 25 80 6f mov %gs:0x26f80,%rbx 28: 02 00 * 2a: 48 8d bb 80 15 00 00 lea 0x1580(%rbx),%rdi <-- trapping instruction 31: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 38: fc ff df 3b: 48 89 fa mov %rdi,%rdx 3e: 48 rex.W 3f: c1 .byte 0xc1