============================================ WARNING: possible recursive locking detected 6.2.0-rc2-syzkaller-00314-gf23395b4049c #0 Not tainted -------------------------------------------- syz-executor.1/24766 is trying to acquire lock: ffff88801ff5aa98 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline] ffff88801ff5aa98 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4316 [inline] ffff88801ff5aa98 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x31c/0xbe0 net/sched/sch_generic.c:340 but task is already holding lock: ffff888146afd0d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline] ffff888146afd0d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4316 [inline] ffff888146afd0d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x31c/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.1/24766: #0: ffff88807e78e2b0 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1725 [inline] #0: ffff88807e78e2b0 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0xa31/0x2df0 net/ipv4/raw.c:638 #1: ffffffff8c791b20 (rcu_read_lock_bh){....}-{1:2}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:95 [inline] #1: ffffffff8c791b20 (rcu_read_lock_bh){....}-{1:2}, at: ip_finish_output2+0x29a/0x2180 net/ipv4/ip_output.c:214 #2: ffffffff8c791b20 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x237/0x3ba0 net/core/dev.c:4166 #3: ffff88807c279258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:360 [inline] #3: ffff88807c279258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:187 [inline] #3: ffff88807c279258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:184 [inline] #3: ffff88807c279258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3797 [inline] #3: ffff88807c279258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1419/0x3ba0 net/core/dev.c:4215 #4: ffff888146afd0d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline] #4: ffff888146afd0d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4316 [inline] #4: ffff888146afd0d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x31c/0xbe0 net/sched/sch_generic.c:340 #5: ffffffff8c791b20 (rcu_read_lock_bh){....}-{1:2}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:95 [inline] #5: ffffffff8c791b20 (rcu_read_lock_bh){....}-{1:2}, at: ip_finish_output2+0x29a/0x2180 net/ipv4/ip_output.c:214 #6: ffffffff8c791b20 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x237/0x3ba0 net/core/dev.c:4166 #7: ffff88801fba2258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:360 [inline] #7: ffff88801fba2258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:187 [inline] #7: ffff88801fba2258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:184 [inline] #7: ffff88801fba2258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3797 [inline] #7: ffff88801fba2258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1419/0x3ba0 net/core/dev.c:4215 stack backtrace: CPU: 1 PID: 24766 Comm: syz-executor.1 Not tainted 6.2.0-rc2-syzkaller-00314-gf23395b4049c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2990 [inline] check_deadlock kernel/locking/lockdep.c:3033 [inline] validate_chain kernel/locking/lockdep.c:3818 [inline] __lock_acquire.cold+0x116/0x3a7 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:350 [inline] __netif_tx_lock include/linux/netdevice.h:4316 [inline] sch_direct_xmit+0x31c/0xbe0 net/sched/sch_generic.c:340 __dev_xmit_skb net/core/dev.c:3810 [inline] __dev_queue_xmit+0x1645/0x3ba0 net/core/dev.c:4215 dev_queue_xmit include/linux/netdevice.h:3035 [inline] neigh_resolve_output net/core/neighbour.c:1571 [inline] neigh_resolve_output+0x51b/0x840 net/core/neighbour.c:1551 neigh_output include/net/neighbour.h:546 [inline] ip_finish_output2+0x78a/0x2180 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+0x31/0x280 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip_mc_output+0x21f/0x710 net/ipv4/ip_output.c:415 dst_output include/net/dst.h:444 [inline] ip_local_out+0xb3/0x1a0 net/ipv4/ip_output.c:126 iptunnel_xmit+0x67e/0x9f0 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0xfd9/0x30f0 net/ipv4/ip_tunnel.c:813 erspan_xmit+0x11a5/0x27d0 net/ipv4/ip_gre.c:715 __netdev_start_xmit include/linux/netdevice.h:4865 [inline] netdev_start_xmit include/linux/netdevice.h:4879 [inline] xmit_one net/core/dev.c:3583 [inline] dev_hard_start_xmit+0x1c2/0x990 net/core/dev.c:3599 sch_direct_xmit+0x1a3/0xbe0 net/sched/sch_generic.c:342 __dev_xmit_skb net/core/dev.c:3810 [inline] __dev_queue_xmit+0x1645/0x3ba0 net/core/dev.c:4215 dev_queue_xmit include/linux/netdevice.h:3035 [inline] neigh_resolve_output net/core/neighbour.c:1571 [inline] neigh_resolve_output+0x51b/0x840 net/core/neighbour.c:1551 neigh_output include/net/neighbour.h:546 [inline] ip_finish_output2+0x78a/0x2180 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+0x31/0x280 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip_mc_output+0x21f/0x710 net/ipv4/ip_output.c:415 dst_output include/net/dst.h:444 [inline] ip_local_out net/ipv4/ip_output.c:126 [inline] ip_send_skb net/ipv4/ip_output.c:1586 [inline] ip_push_pending_frames+0x129/0x2b0 net/ipv4/ip_output.c:1606 raw_sendmsg+0x1338/0x2df0 net/ipv4/raw.c:645 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:827 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x334/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmmsg+0x18f/0x460 net/socket.c:2616 __do_sys_sendmmsg net/socket.c:2645 [inline] __se_sys_sendmmsg net/socket.c:2642 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2642 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6761a8c0c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f67627d6168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f6761bac120 RCX: 00007f6761a8c0c9 RDX: 0000000000000001 RSI: 0000000020003380 RDI: 0000000000000003 RBP: 00007f6761ae7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffdb25adef R14: 00007f67627d6300 R15: 0000000000022000