===================================== WARNING: bad unlock balance detected! 5.5.0-rc5-syzkaller #0 Not tainted ------------------------------------- syz-executor.4/9565 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.4/9565: #0: ffffffff89dd37a8 (tomoyo_ss){....}, at: tomoyo_path_perm+0x1cb/0x430 security/tomoyo/file.c:847 #1: ffffc90000da8d50 ((&ndev->rs_timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:172 [inline] #1: ffffc90000da8d50 ((&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: ffff8880a0382250 (&dev->qdisc_tx_busylock_key#28){+...}, at: spin_trylock include/linux/spinlock.h:348 [inline] #5: ffff8880a0382250 (&dev->qdisc_tx_busylock_key#28){+...}, at: qdisc_run_begin include/net/sch_generic.h:159 [inline] #5: ffff8880a0382250 (&dev->qdisc_tx_busylock_key#28){+...}, at: __dev_xmit_skb net/core/dev.c:3611 [inline] #5: ffff8880a0382250 (&dev->qdisc_tx_busylock_key#28){+...}, at: __dev_queue_xmit+0x2412/0x35c0 net/core/dev.c:3982 #6: ffff8880a0382138 (&dev->qdisc_running_key#28){+...}, at: dev_queue_xmit+0x18/0x20 net/core/dev.c:4046 stack backtrace: CPU: 1 PID: 9565 Comm: syz-executor.4 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_resolve_output net/core/neighbour.c:1487 [inline] neigh_resolve_output+0x5c4/0x990 net/core/neighbour.c:1467 neigh_output include/net/neighbour.h:510 [inline] ip6_finish_output2+0x109a/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:write_comp_data+0x0/0x70 kernel/kcov.c:207 Code: 83 fa 02 75 20 48 8b 88 88 13 00 00 8b 80 84 13 00 00 48 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 5d c3 0f 1f 00 <65> 4c 8b 04 25 c0 1e 02 00 65 8b 05 98 28 8d 7e a9 00 01 1f 00 75 RSP: 0018:ffffc900020279f8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff8880a2bac500 RCX: ffffffff83630f91 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffffc90002027a00 R08: ffff888066372440 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffc90002027b48 R15: 0000000000000000 tomoyo_check_acl+0xd1/0x3e0 security/tomoyo/domain.c:173 tomoyo_path_permission security/tomoyo/file.c:586 [inline] tomoyo_path_permission+0x1fb/0x360 security/tomoyo/file.c:573 tomoyo_path_perm+0x318/0x430 security/tomoyo/file.c:838 tomoyo_inode_getattr+0x1d/0x30 security/tomoyo/tomoyo.c:129 security_inode_getattr+0xf2/0x150 security/security.c:1222 vfs_getattr+0x25/0x70 fs/stat.c:115 vfs_statx_fd+0x71/0xc0 fs/stat.c:145 vfs_fstat include/linux/fs.h:3265 [inline] __do_sys_newfstat+0x9b/0x120 fs/stat.c:378 __se_sys_newfstat fs/stat.c:375 [inline] __x64_sys_newfstat+0x54/0x80 fs/stat.c:375 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a2b4 Code: c0 d4 ff ff ff 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 83 ff 01 89 f0 77 31 48 63 f8 48 89 d6 b8 05 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 04 f3 c3 66 90 48 c7 c2 d4 ff ff ff f7 d8 64 RSP: 002b:00007fff7a181e48 EFLAGS: 00000246 ORIG_RAX: 0000000000000005 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a2b4 RDX: 00007fff7a181e50 RSI: 00007fff7a181e50 RDI: 0000000000000003 RBP: 00000000000005a2 R08: 0000000000000001 R09: 0000000001a70940 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff7a183030 R13: 00007fff7a183020 R14: 0000000000000000 R15: 00007fff7a183030