BUG: soft lockup in mld_dad_timer_expire (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 66722c42ec91 Linux 4.14.256
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14328531b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=b8004ce84f364d9
dashboard link: https://syzkaller.appspot.com/bug?extid=0d0a73af53b7c0625dde
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0d0a73...@syzkaller.appspotmail.com

Bluetooth: hci3 command 0x0419 tx timeout
audit: type=1804 audit(1638849337.074:2): pid=9433 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir435365706/syzkaller.0AnEuv/0/file0" dev="sda1" ino=13897 res=1
watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [syz-executor.4:9420]
Modules linked in:
irq event stamp: 7019491
hardirqs last enabled at (7019490): [<ffffffff817eaf70>] kmem_cache_free+0x160/0x2b0 mm/slab.c:3759
hardirqs last disabled at (7019491): [<ffffffff874018ae>] apic_timer_interrupt+0x8e/0xa0 arch/x86/entry/entry_64.S:793
softirqs last enabled at (2802): [<ffffffff862065f8>] fib_table_delete+0x7c8/0xe20 net/ipv4/fib_trie.c:1590
softirqs last disabled at (3057): [<ffffffff81321d13>] invoke_softirq kernel/softirq.c:368 [inline]
softirqs last disabled at (3057): [<ffffffff81321d13>] irq_exit+0x193/0x240 kernel/softirq.c:409
CPU: 0 PID: 9420 Comm: syz-executor.4 Not tainted 4.14.256-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880b4c96140 task.stack: ffff88806afb0000
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline]
RIP: 0010:kmem_cache_free+0x173/0x2b0 mm/slab.c:3759
RSP: 0018:ffff8880ba406f18 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000007 RBX: ffff8880589e8500 RCX: 1ffff11016992d4c
RDX: 0000000000000000 RSI: ffff8880b4c96b30 RDI: 0000000000000286
RBP: ffff88823a817240 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000286
R13: ffffffff85be5e18 R14: ffffffff85c2a95a R15: 00000000000354c0
FS: 00007f8b15a99700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000186bd10 CR3: 0000000096e75000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
kfree_skbmem+0x98/0x100 net/core/skbuff.c:595
__kfree_skb net/core/skbuff.c:655 [inline]
kfree_skb+0xf4/0x390 net/core/skbuff.c:672
enqueue_to_backlog+0x23a/0xce0 net/core/dev.c:3906
netif_rx_internal+0xe2/0x800 net/core/dev.c:4072
loopback_xmit+0x23a/0x580 drivers/net/loopback.c:91
__netdev_start_xmit include/linux/netdevice.h:4051 [inline]
netdev_start_xmit include/linux/netdevice.h:4060 [inline]
xmit_one net/core/dev.c:3005 [inline]
dev_hard_start_xmit+0x188/0x890 net/core/dev.c:3021
__dev_queue_xmit+0x1d7f/0x2480 net/core/dev.c:3521
neigh_hh_output include/net/neighbour.h:490 [inline]
neigh_output include/net/neighbour.h:498 [inline]
ip_finish_output2+0x9db/0x1340 net/ipv4/ip_output.c:230
ip_do_fragment+0xa24/0x1fb0 net/ipv4/ip_output.c:815
ip_fragment.constprop.0+0x146/0x200 net/ipv4/ip_output.c:551
ip_finish_output+0x89e/0xc50 net/ipv4/ip_output.c:316
NF_HOOK_COND include/linux/netfilter.h:239 [inline]
ip_output+0x1cd/0x510 net/ipv4/ip_output.c:406
dst_output include/net/dst.h:470 [inline]
ip_local_out+0x93/0x170 net/ipv4/ip_output.c:125
iptunnel_xmit+0x5cc/0x950 net/ipv4/ip_tunnel_core.c:91
geneve_xmit_skb drivers/net/geneve.c:867 [inline]
geneve_xmit+0xf15/0x2ca0 drivers/net/geneve.c:948
__netdev_start_xmit include/linux/netdevice.h:4051 [inline]
netdev_start_xmit include/linux/netdevice.h:4060 [inline]
xmit_one net/core/dev.c:3005 [inline]
dev_hard_start_xmit+0x188/0x890 net/core/dev.c:3021
__dev_queue_xmit+0x1d7f/0x2480 net/core/dev.c:3521
neigh_hh_output include/net/neighbour.h:490 [inline]
neigh_output include/net/neighbour.h:498 [inline]
ip6_finish_output2+0xc6a/0x1f10 net/ipv6/ip6_output.c:120
ip6_finish_output+0x5c6/0xd50 net/ipv6/ip6_output.c:192
NF_HOOK_COND include/linux/netfilter.h:239 [inline]
ip6_output+0x1c5/0x660 net/ipv6/ip6_output.c:209
dst_output include/net/dst.h:470 [inline]
NF_HOOK include/linux/netfilter.h:250 [inline]
mld_sendpack+0x5fe/0xea0 net/ipv6/mcast.c:1657
mld_send_initial_cr.part.0+0xf5/0x140 net/ipv6/mcast.c:2074
mld_send_initial_cr net/ipv6/mcast.c:1170 [inline]
mld_dad_timer_expire+0x140/0x520 net/ipv6/mcast.c:2093
call_timer_fn+0x14a/0x650 kernel/time/timer.c:1280
expire_timers+0x232/0x4d0 kernel/time/timer.c:1319
__run_timers kernel/time/timer.c:1637 [inline]
run_timer_softirq+0x1d5/0x5a0 kernel/time/timer.c:1650
__do_softirq+0x24d/0x9ff kernel/softirq.c:288
invoke_softirq kernel/softirq.c:368 [inline]
irq_exit+0x193/0x240 kernel/softirq.c:409
exiting_irq arch/x86/include/asm/apic.h:638 [inline]
smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1106
apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793
</IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x3d/0x50 kernel/kcov.c:87
RSP: 0018:ffff88806afb67b0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000040000 RBX: 00007f8b16b23af9 RCX: ffffc900079fd000
RDX: 000000000000822d RSI: ffffffff815e2676 RDI: ffff8880ba42ca8c
RBP: 00007f8b16b23af9 R08: 0000000000000000 R09: 0000000000020012
R10: ffff8880b4c96a18 R11: ffff8880b4c96140 R12: ffff88806afb68a8
R13: 0000000000000000 R14: ffff88813fe74040 R15: 00000000000000c0
bpf_jit_kallsyms_enabled include/linux/filter.h:803 [inline]
bpf_prog_kallsyms_find kernel/bpf/core.c:420 [inline]
is_bpf_text_address+0x56/0x150 kernel/bpf/core.c:458
kernel_text_address kernel/extable.c:150 [inline]
kernel_text_address+0xbd/0xf0 kernel/extable.c:120
__kernel_text_address+0x9/0x30 kernel/extable.c:105
unwind_get_return_address arch/x86/kernel/unwind_orc.c:252 [inline]
unwind_get_return_address+0x51/0x90 arch/x86/kernel/unwind_orc.c:247
__save_stack_trace+0xa0/0x160 arch/x86/kernel/stacktrace.c:45
save_stack mm/kasan/kasan.c:447 [inline]
set_track mm/kasan/kasan.c:459 [inline]
kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
slab_post_alloc_hook mm/slab.h:442 [inline]
slab_alloc mm/slab.c:3390 [inline]
__do_kmalloc mm/slab.c:3718 [inline]
__kmalloc+0x144/0x400 mm/slab.c:3729
kmalloc include/linux/slab.h:493 [inline]
kzalloc include/linux/slab.h:661 [inline]
tnode_alloc net/ipv4/fib_trie.c:343 [inline]
tnode_new+0x74/0x2a0 net/ipv4/fib_trie.c:390
inflate net/ipv4/fib_trie.c:601 [inline]
resize+0x869/0x1d00 net/ipv4/fib_trie.c:874
trie_rebalance net/ipv4/fib_trie.c:1014 [inline]
fib_remove_alias net/ipv4/fib_trie.c:1510 [inline]
fib_table_delete+0xa70/0xe20 net/ipv4/fib_trie.c:1585
fib_magic+0x2db/0x460 net/ipv4/fib_frontend.c:863
fib_del_ifaddr+0x9f4/0xe10 net/ipv4/fib_frontend.c:1043
fib_inetaddr_event+0xa5/0x260 net/ipv4/fib_frontend.c:1174
notifier_call_chain+0x108/0x1a0 kernel/notifier.c:93
__blocking_notifier_call_chain kernel/notifier.c:317 [inline]
__blocking_notifier_call_chain kernel/notifier.c:304 [inline]
blocking_notifier_call_chain kernel/notifier.c:328 [inline]
blocking_notifier_call_chain+0x79/0x90 kernel/notifier.c:325
__inet_del_ifa+0x4c1/0xaf0 net/ipv4/devinet.c:409
inet_del_ifa net/ipv4/devinet.c:439 [inline]
inetdev_destroy net/ipv4/devinet.c:304 [inline]
inetdev_event+0x4ec/0x10a0 net/ipv4/devinet.c:1529
notifier_call_chain+0x108/0x1a0 kernel/notifier.c:93
call_netdevice_notifiers_info net/core/dev.c:1667 [inline]
call_netdevice_notifiers_mtu net/core/dev.c:1706 [inline]
dev_set_mtu+0x23d/0x3c0 net/core/dev.c:6921
do_setlink+0x4f3/0x2bf0 net/core/rtnetlink.c:2055
rtnl_group_changelink net/core/rtnetlink.c:2512 [inline]
rtnl_newlink+0xccc/0x1860 net/core/rtnetlink.c:2666
rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4320
netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2441
netlink_unicast_kernel net/netlink/af_netlink.c:1294 [inline]
netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1320
netlink_sendmsg+0x638/0xb90 net/netlink/af_netlink.c:1886
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xb5/0x100 net/socket.c:656
___sys_sendmsg+0x6c8/0x800 net/socket.c:2062
__sys_sendmsg+0xa3/0x120 net/socket.c:2096
SYSC_sendmsg net/socket.c:2107 [inline]
SyS_sendmsg+0x27/0x40 net/socket.c:2103
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f8b16b23af9
RSP: 002b:00007f8b15a99188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8b16c36f60 RCX: 00007f8b16b23af9
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00007f8b16b7dff7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2238aeff R14: 00007f8b15a99300 R15: 0000000000022000
Code: eb 11 48 63 75 74 48 89 df e8 7a 3b 9b 01 e9 11 ff ff ff e8 60 c8 c2 ff 48 83 3d 50 e4 71 07 00 0f 84 22 01 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 e9 31 ff ff ff 65 8b 05 9c 71 83 7e 83 f8 07 0f
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff8723c75e
----------------
Code disassembly (best guess):
0: eb 11 jmp 0x13
2: 48 63 75 74 movslq 0x74(%rbp),%rsi
6: 48 89 df mov %rbx,%rdi
9: e8 7a 3b 9b 01 callq 0x19b3b88
e: e9 11 ff ff ff jmpq 0xffffff24
13: e8 60 c8 c2 ff callq 0xffc2c878
18: 48 83 3d 50 e4 71 07 cmpq $0x0,0x771e450(%rip) # 0x771e470
1f: 00
20: 0f 84 22 01 00 00 je 0x148
26: 4c 89 e7 mov %r12,%rdi
29: 57 push %rdi
2a: 9d popfq
* 2b: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) <-- trapping instruction
30: e9 31 ff ff ff jmpq 0xffffff66
35: 65 8b 05 9c 71 83 7e mov %gs:0x7e83719c(%rip),%eax # 0x7e8371d8
3c: 83 f8 07 cmp $0x7,%eax
3f: 0f .byte 0xf


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.