============================================
WARNING: possible recursive locking detected
6.1.127-syzkaller #0 Not tainted
--------------------------------------------
syz.2.573/7061 is trying to acquire lock:
ffff88806742ca18 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff88806742ca18 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3894 [inline]
ffff88806742ca18 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: __dev_queue_xmit+0x22db/0x3d50 net/core/dev.c:4269
but task is already holding lock:
ffff88801ead5258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
ffff88801ead5258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
ffff88801ead5258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3851 [inline]
ffff88801ead5258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: __dev_queue_xmit+0x12c7/0x3d50 net/core/dev.c:4269
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
lock(dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
*** DEADLOCK ***
May be due to missing lock nesting notation
8 locks held by syz.2.573/7061:
#0: ffff888067483590 (&u->iolock){+.+.}-{3:3}, at: __unix_dgram_recvmsg+0x24d/0x1260 net/unix/af_unix.c:2424
#1: ffffc900001e0bc0 ((&app->join_timer)#2){+.-.}-{0:0}, at: call_timer_fn+0xc2/0x6b0 kernel/time/timer.c:1501
#2: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#2: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:843 [inline]
#2: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2d6/0x3d50 net/core/dev.c:4226
#3: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#3: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#3: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: bond_start_xmit+0x128/0x1d50 drivers/net/bonding/bond_main.c:5523
#4: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#4: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:843 [inline]
#4: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2d6/0x3d50 net/core/dev.c:4226
#5: ffff88801ead5258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
#5: ffff88801ead5258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
#5: ffff88801ead5258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3851 [inline]
#5: ffff88801ead5258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: __dev_queue_xmit+0x12c7/0x3d50 net/core/dev.c:4269
#6: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#6: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#6: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x402/0x1330 net/ipv4/ip_output.c:221
#7: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#7: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:843 [inline]
#7: ffffffff8d32b120 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2d6/0x3d50 net/core/dev.c:4226
stack backtrace:
CPU: 1 PID: 7061 Comm: syz.2.573 Not tainted 6.1.127-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
print_deadlock_bug kernel/locking/lockdep.c:2983 [inline]
check_deadlock kernel/locking/lockdep.c:3026 [inline]
validate_chain+0x4711/0x5950 kernel/locking/lockdep.c:3812
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__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:351 [inline]
__dev_xmit_skb net/core/dev.c:3894 [inline]
__dev_queue_xmit+0x22db/0x3d50 net/core/dev.c:4269
dev_queue_xmit include/linux/netdevice.h:3043 [inline]
neigh_hh_output include/net/neighbour.h:528 [inline]
neigh_output include/net/neighbour.h:542 [inline]
ip_finish_output2+0xcfc/0x1330 net/ipv4/ip_output.c:228
iptunnel_xmit+0x513/0x920 net/ipv4/ip_tunnel_core.c:82
ip_tunnel_xmit+0x1f87/0x2690 net/ipv4/ip_tunnel.c:858
__gre_xmit net/ipv4/ip_gre.c:474 [inline]
gre_tap_xmit+0x4eb/0x6e0 net/ipv4/ip_gre.c:751
__netdev_start_xmit include/linux/netdevice.h:4888 [inline]
netdev_start_xmit include/linux/netdevice.h:4902 [inline]
xmit_one net/core/dev.c:3627 [inline]
dev_hard_start_xmit+0x261/0x8c0 net/core/dev.c:3643
sch_direct_xmit+0x2b2/0x5e0 net/sched/sch_generic.c:342
__dev_xmit_skb net/core/dev.c:3864 [inline]
__dev_queue_xmit+0x1a7a/0x3d50 net/core/dev.c:4269
dev_queue_xmit include/linux/netdevice.h:3043 [inline]
bond_dev_queue_xmit+0x143/0x240 drivers/net/bonding/bond_main.c:307
__bond_start_xmit drivers/net/bonding/bond_main.c:5503 [inline]
bond_start_xmit+0xdb5/0x1d50 drivers/net/bonding/bond_main.c:5525
__netdev_start_xmit include/linux/netdevice.h:4888 [inline]
netdev_start_xmit include/linux/netdevice.h:4902 [inline]
xmit_one net/core/dev.c:3627 [inline]
dev_hard_start_xmit+0x261/0x8c0 net/core/dev.c:3643
__dev_queue_xmit+0x1b5d/0x3d50 net/core/dev.c:4303
dev_queue_xmit include/linux/netdevice.h:3043 [inline]
mrp_queue_xmit net/802/mrp.c:364 [inline]
mrp_join_timer+0x9f/0x180 net/802/mrp.c:608
call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1504
expire_timers kernel/time/timer.c:1549 [inline]
__run_timers+0x67c/0x890 kernel/time/timer.c:1820
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
__do_softirq kernel/softirq.c:605 [inline]
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x157/0x240 kernel/softirq.c:654
irq_exit_rcu+0x5/0x20 kernel/softirq.c:666
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 02 f0 24 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 f7 4f a1 f6 65 8b 05 98 2f 45 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc9000673f5a0 EFLAGS: 00000206
RAX: 961401c6144c7600 RBX: 1ffff92000ce7eb8 RCX: ffffffff816b127a
RDX: dffffc0000000000 RSI: ffffffff8b0c0340 RDI: 0000000000000001
RBP: ffffc9000673f630 R08: dffffc0000000000 R09: fffffbfff224a061
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000ce7eb4 R14: ffffc9000673f5c0 R15: 0000000000000246
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
__skb_try_recv_datagram+0x1c7/0x6a0 net/core/datagram.c:265
__unix_dgram_recvmsg+0x3c1/0x1260 net/unix/af_unix.c:2427
____sys_recvmsg+0x285/0x530
___sys_recvmsg net/socket.c:2780 [inline]
do_recvmmsg+0x46d/0xad0 net/socket.c:2874
__sys_recvmmsg net/socket.c:2953 [inline]
__do_sys_recvmmsg net/socket.c:2976 [inline]
__se_sys_recvmmsg net/socket.c:2969 [inline]
__x64_sys_recvmmsg+0x195/0x240 net/socket.c:2969
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcfe818cda9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcfe8f38038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fcfe83a6080 RCX: 00007fcfe818cda9
RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00007fcfe820e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcfe83a6080 R15: 00007ffd9fa59338
----------------
Code disassembly (best guess):
0: 9c pushf
1: 8f 44 24 20 pop 0x20(%rsp)
5: 42 80 3c 23 00 cmpb $0x0,(%rbx,%r12,1)
a: 74 08 je 0x14
c: 4c 89 f7 mov %r14,%rdi
f: e8 02 f0 24 f7 call 0xf724f016
14: f6 44 24 21 02 testb $0x2,0x21(%rsp)
19: 75 4e jne 0x69
1b: 41 f7 c7 00 02 00 00 test $0x200,%r15d
22: 74 01 je 0x25
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 f7 4f a1 f6 call 0xf6a15026 <-- trapping instruction
2f: 65 8b 05 98 2f 45 75 mov %gs:0x75452f98(%rip),%eax # 0x75452fce
36: 85 c0 test %eax,%eax
38: 74 3f je 0x79
3a: 48 rex.W
3b: c7 .byte 0xc7
3c: 04 24 add $0x24,%al
3e: 0e (bad)
3f: 36 ss