===================================== WARNING: bad unlock balance detected! 5.5.0-rc5-syzkaller #0 Not tainted ------------------------------------- syz-executor.0/9671 is trying to release lock (&dev->qdisc_xmit_lock_key) at: [] spin_unlock include/linux/spinlock.h:378 [inline] [] __netif_tx_unlock include/linux/netdevice.h:3966 [inline] [] sch_direct_xmit+0x3fa/0xd30 net/sched/sch_generic.c:315 but there are no more locks to release! other info that might help us debug this: 7 locks held by syz-executor.0/9671: #0: ffff888097dcd258 (&mm->mmap_sem#2){++++}, at: do_user_addr_fault arch/x86/mm/fault.c:1382 [inline] #0: ffff888097dcd258 (&mm->mmap_sem#2){++++}, at: __do_page_fault+0x33c/0xd80 arch/x86/mm/fault.c:1506 #1: ffffc90000007d50 ((&ndev->rs_timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:172 [inline] #1: ffffc90000007d50 ((&ndev->rs_timer)){+.-.}, at: call_timer_fn+0xe0/0x780 kernel/time/timer.c:1394 #2: ffffffff899a3f00 (rcu_read_lock){....}, at: ip6_nd_hdr net/ipv6/ndisc.c:463 [inline] #2: ffffffff899a3f00 (rcu_read_lock){....}, at: ndisc_send_skb+0x7fe/0x1490 net/ipv6/ndisc.c:499 #3: ffffffff899a3ec0 (rcu_read_lock_bh){....}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline] #3: ffffffff899a3ec0 (rcu_read_lock_bh){....}, at: ip6_finish_output2+0x214/0x25c0 net/ipv6/ip6_output.c:102 #4: ffffffff899a3ec0 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x20a/0x35c0 net/core/dev.c:3948 #5: ffff888096db1250 (&dev->qdisc_tx_busylock_key#23){+...}, at: spin_trylock include/linux/spinlock.h:348 [inline] #5: ffff888096db1250 (&dev->qdisc_tx_busylock_key#23){+...}, at: qdisc_run_begin include/net/sch_generic.h:159 [inline] #5: ffff888096db1250 (&dev->qdisc_tx_busylock_key#23){+...}, at: __dev_xmit_skb net/core/dev.c:3611 [inline] #5: ffff888096db1250 (&dev->qdisc_tx_busylock_key#23){+...}, at: __dev_queue_xmit+0x2412/0x35c0 net/core/dev.c:3982 #6: ffff888096db1138 (&dev->qdisc_running_key#23){+...}, at: dev_queue_xmit+0x18/0x20 net/core/dev.c:4046 stack backtrace: CPU: 0 PID: 9671 Comm: syz-executor.0 Not tainted 5.5.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_unlock_imbalance_bug kernel/locking/lockdep.c:4008 [inline] print_unlock_imbalance_bug.cold+0x114/0x123 kernel/locking/lockdep.c:3984 __lock_release kernel/locking/lockdep.c:4242 [inline] lock_release+0x5f2/0x960 kernel/locking/lockdep.c:4503 __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_unlock+0x16/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:378 [inline] __netif_tx_unlock include/linux/netdevice.h:3966 [inline] sch_direct_xmit+0x3fa/0xd30 net/sched/sch_generic.c:315 __dev_xmit_skb net/core/dev.c:3621 [inline] __dev_queue_xmit+0x2707/0x35c0 net/core/dev.c:3982 dev_queue_xmit+0x18/0x20 net/core/dev.c:4046 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip6_finish_output2+0xfbe/0x25c0 net/ipv6/ip6_output.c:116 __ip6_finish_output+0x444/0xaa0 net/ipv6/ip6_output.c:142 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x25e/0x880 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xf1f/0x1490 net/ipv6/ndisc.c:505 ndisc_send_rs+0x134/0x720 net/ipv6/ndisc.c:699 addrconf_rs_timer+0x30f/0x6e0 net/ipv6/addrconf.c:3879 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:vmacache_valid_mm mm/vmacache.c:33 [inline] RIP: 0010:vmacache_valid mm/vmacache.c:46 [inline] RIP: 0010:vmacache_find+0x25/0x310 mm/vmacache.c:69 Code: 12 00 eb cb 90 55 48 89 e5 41 57 41 56 41 55 49 89 f5 41 54 53 48 83 ec 18 48 89 7d c8 e8 43 fc d4 ff 65 48 ff 05 e3 42 63 7e <65> 48 8b 1c 25 c0 1e 02 00 48 8d bb 28 04 00 00 48 b8 00 00 00 00 RSP: 0000:ffffc9000204fe18 EFLAGS: 00000203 ORIG_RAX: ffffffffffffff13 RAX: ffff888097986400 RBX: ffff888097dcd140 RCX: ffff888097986c98 RDX: 0000000000000000 RSI: ffffffff819ff94d RDI: ffff888097dcd140 RBP: ffffc9000204fe58 R08: ffff888097986400 R09: fffffbfff165e7ae R10: ffff888097986c98 R11: ffff888097986400 R12: 0000000000717158 R13: 0000000000717158 R14: ffffc9000204ff58 R15: ffffc9000204ffe0 find_vma+0x23/0x170 mm/mmap.c:2223 do_user_addr_fault arch/x86/mm/fault.c:1402 [inline] __do_page_fault+0x37a/0xd80 arch/x86/mm/fault.c:1506 do_page_fault+0x38/0x590 arch/x86/mm/fault.c:1530 page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203 RIP: 0033:0x404ea9 Code: e7 c7 44 24 0c 78 00 00 00 e8 c3 8b 05 00 85 c0 0f 85 8d 01 00 00 4d 8d 75 88 ba 78 00 00 00 48 89 ee c7 44 24 70 00 00 00 00 <49> c7 45 f8 00 00 00 00 4c 89 f7 49 c7 45 b8 00 00 00 00 49 c7 45 RSP: 002b:00007fffd4b4d2c0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000045da5a RDX: 0000000000000078 RSI: 00007fffd4b4d2d0 RDI: 0000000000000003 RBP: 00007fffd4b4d2d0 R08: 00007fffd4b4d2cc R09: 000000000000000a R10: 00007fffd4b4d2d0 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000717160 R14: 00000000007170e8 R15: 0000000000000000