============================================
WARNING: possible recursive locking detected
6.8.0-syzkaller-05204-g237bb5f7f7f5 #0 Not tainted
--------------------------------------------
syz-executor.0/29086 is trying to acquire lock:
ffff88805c6c53e0 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff88805c6c53e0 (&br->multicast_lock){+.-.}-{2:2}, at: br_ip6_multicast_query net/bridge/br_multicast.c:3523 [inline]
ffff88805c6c53e0 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_ipv6_rcv net/bridge/br_multicast.c:3919 [inline]
ffff88805c6c53e0 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_rcv+0x30e2/0x8180 net/bridge/br_multicast.c:3974
but task is already holding lock:
ffff888023a093e0 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff888023a093e0 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_port_query_expired+0x64/0x3b0 net/bridge/br_multicast.c:1905
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&br->multicast_lock);
lock(&br->multicast_lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
8 locks held by syz-executor.0/29086:
#0: ffffffff8f385a08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8f385a08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x10d0 net/core/rtnetlink.c:6592
#1: ffffffff8e00d500 (console_lock){+.+.}-{0:0}, at: _printk+0xd5/0x120 kernel/printk/printk.c:2317
#2: ffffffff8e00d130 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:303 [inline]
#2: ffffffff8e00d130 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:232 [inline]
#2: ffffffff8e00d130 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:286 [inline]
#2: ffffffff8e00d130 (console_srcu){....}-{0:0}, at: console_flush_all+0x14a/0xec0 kernel/printk/printk.c:2948
#3: ffffc90000a08c00 ((&pmctx->ip6_own_query.timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x600 kernel/time/timer.c:1789
#4: ffff888023a093e0 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#4: ffff888023a093e0 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_port_query_expired+0x64/0x3b0 net/bridge/br_multicast.c:1905
#5: ffffffff8e131980 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#5: ffffffff8e131980 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
#5: ffffffff8e131980 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4260
#6: ffffffff8e131980 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#6: ffffffff8e131980 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
#6: ffffffff8e131980 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4260
#7: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
#7: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
#7: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: br_dev_xmit+0x1b9/0x1a10 net/bridge/br_device.c:44
stack backtrace:
CPU: 1 PID: 29086 Comm: syz-executor.0 Not tainted 6.8.0-syzkaller-05204-g237bb5f7f7f5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
check_deadlock kernel/locking/lockdep.c:3062 [inline]
validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856
__lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
__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:351 [inline]
br_ip6_multicast_query net/bridge/br_multicast.c:3523 [inline]
br_multicast_ipv6_rcv net/bridge/br_multicast.c:3919 [inline]
br_multicast_rcv+0x30e2/0x8180 net/bridge/br_multicast.c:3974
br_dev_xmit+0xb17/0x1a10 net/bridge/br_device.c:90
__netdev_start_xmit include/linux/netdevice.h:4903 [inline]
netdev_start_xmit include/linux/netdevice.h:4917 [inline]
xmit_one net/core/dev.c:3531 [inline]
dev_hard_start_xmit+0x26a/0x790 net/core/dev.c:3547
__dev_queue_xmit+0x19f4/0x3b10 net/core/dev.c:4335
dev_queue_xmit include/linux/netdevice.h:3091 [inline]
vlan_dev_hard_start_xmit+0x36c/0x5f0 net/8021q/vlan_dev.c:125
__netdev_start_xmit include/linux/netdevice.h:4903 [inline]
netdev_start_xmit include/linux/netdevice.h:4917 [inline]
xmit_one net/core/dev.c:3531 [inline]
dev_hard_start_xmit+0x26a/0x790 net/core/dev.c:3547
__dev_queue_xmit+0x19f4/0x3b10 net/core/dev.c:4335
dev_queue_xmit include/linux/netdevice.h:3091 [inline]
br_dev_queue_push_xmit+0x701/0x8d0 net/bridge/br_forward.c:53
NF_HOOK include/linux/netfilter.h:314 [inline]
__br_multicast_send_query+0x2ecb/0x4750 net/bridge/br_multicast.c:1809
br_multicast_send_query+0x4ee/0x6b0 net/bridge/br_multicast.c:1888
br_multicast_port_query_expired+0x2d4/0x3b0 net/bridge/br_multicast.c:1913
call_timer_fn+0x17e/0x600 kernel/time/timer.c:1792
expire_timers kernel/time/timer.c:1843 [inline]
__run_timers kernel/time/timer.c:2408 [inline]
__run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2419
run_timer_base kernel/time/timer.c:2428 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2438
__do_softirq+0x2bc/0x943 kernel/softirq.c:554
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_flush_all+0x9cd/0xec0 kernel/printk/printk.c:2962
Code: 48 21 c3 0f 85 fa 01 00 00 e8 1f 6a 1f 00 48 8b 5c 24 38 4d 85 f6 75 07 e8 10 6a 1f 00 eb 06 e8 09 6a 1f 00 fb 48 8b 44 24 58 <42> 0f b6 04 28 84 c0 0f 85 4a 02 00 00 0f b6 1b 31 ff 89 de e8 ea
RSP: 0018:ffffc900034c67c0 EFLAGS: 00000283
RAX: 1ffff92000698d44 RBX: ffffc900034c6a20 RCX: 0000000000040000
RDX: ffffc9000b40a000 RSI: 0000000000002822 RDI: 0000000000002823
RBP: ffffc900034c6970 R08: ffffffff8175863e R09: 1ffffffff2598ea0
R10: dffffc0000000000 R11: fffffbfff2598ea1 R12: ffffffff8e8f47a0
R13: dffffc0000000000 R14: 0000000000000200 R15: ffffffff8e8f47f8
console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3025
vprintk_emit+0x509/0x720 kernel/printk/printk.c:2292
_printk+0xd5/0x120 kernel/printk/printk.c:2317
validate_nla lib/nlattr.c:414 [inline]
__nla_validate_parse+0x19fe/0x2f70 lib/nlattr.c:635
__nla_parse+0x40/0x60 lib/nlattr.c:732
nla_parse_nested_deprecated include/net/netlink.h:1325 [inline]
choke_change+0xe6/0x15b0 net/sched/sch_choke.c:350
qdisc_change net/sched/sch_api.c:1416 [inline]
tc_modify_qdisc+0x190d/0x1e40 net/sched/sch_api.c:1746
rtnetlink_rcv_msg+0x89b/0x10d0 net/core/rtnetlink.c:6595
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2559
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8e1/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
___sys_sendmsg net/socket.c:2638 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f7f5807dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7f58e600c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f7f581abf80 RCX: 00007f7f5807dda9
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003
RBP: 00007f7f580ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7f581abf80 R15: 00007ffd7d351c28
----------------
Code disassembly (best guess):
0: 48 21 c3 and %rax,%rbx
3: 0f 85 fa 01 00 00 jne 0x203
9: e8 1f 6a 1f 00 call 0x1f6a2d
e: 48 8b 5c 24 38 mov 0x38(%rsp),%rbx
13: 4d 85 f6 test %r14,%r14
16: 75 07 jne 0x1f
18: e8 10 6a 1f 00 call 0x1f6a2d
1d: eb 06 jmp 0x25
1f: e8 09 6a 1f 00 call 0x1f6a2d
24: fb sti
25: 48 8b 44 24 58 mov 0x58(%rsp),%rax
* 2a: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 0f 85 4a 02 00 00 jne 0x281
37: 0f b6 1b movzbl (%rbx),%ebx
3a: 31 ff xor %edi,%edi
3c: 89 de mov %ebx,%esi
3e: e8 .byte 0xe8
3f: ea (bad)