kernel panic: audit: out of memory in audit_log_start

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 98db2bf2 Linux 4.14.171
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1485a3d9e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=365f8162d5a0794b
dashboard link: https://syzkaller.appspot.com/bug?extid=c62843225d5acf535508
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c62843...@syzkaller.appspotmail.com

RAX: ffffffffffffffda RBX: 00007ff54e8f26d4 RCX: 000000000045c429
RDX: 04000000000000eb RSI: 000000002000d180 RDI: 0000000000000006
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007
R13: 00000000000008d2 R14: 00000000004cb32d R15: 0000000000000003
Kernel panic - not syncing: audit: out of memory in audit_log_start

CPU: 1 PID: 20855 Comm: syz-executor.4 Not tainted 4.14.171-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x142/0x197 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
audit_panic.cold+0x32/0x32 kernel/audit.c:280
audit_log_lost kernel/audit.c:350 [inline]
audit_log_lost+0x56/0x100 kernel/audit.c:322
audit_log_start kernel/audit.c:1742 [inline]
audit_log_start+0x4dd/0x690 kernel/audit.c:1690
audit_tg.part.0+0x25/0x250 net/netfilter/xt_AUDIT.c:77
audit_tg net/netfilter/xt_AUDIT.c:75 [inline]
audit_tg_ebt+0x57/0x75 net/netfilter/xt_AUDIT.c:114
ebt_do_table+0x12b0/0x1ac0 net/bridge/netfilter/ebtables.c:239
ebt_in_hook+0x65/0x80 net/bridge/netfilter/ebtable_filter.c:63
nf_hook_entry_hookfn include/linux/netfilter.h:108 [inline]
nf_hook_slow+0xaf/0x1b0 net/netfilter/core.c:467
nf_hook include/linux/netfilter.h:205 [inline]
NF_HOOK include/linux/netfilter.h:248 [inline]
__br_forward+0x312/0x9c0 net/bridge/br_forward.c:111
deliver_clone+0x61/0xc0 net/bridge/br_forward.c:127
maybe_deliver net/bridge/br_forward.c:168 [inline]
maybe_deliver net/bridge/br_forward.c:156 [inline]
br_flood+0x3c8/0x530 net/bridge/br_forward.c:210
br_dev_xmit+0x8d7/0xd40 net/bridge/br_device.c:87
__netdev_start_xmit include/linux/netdevice.h:4039 [inline]
netdev_start_xmit include/linux/netdevice.h:4048 [inline]
xmit_one net/core/dev.c:3009 [inline]
dev_hard_start_xmit+0x18c/0x8b0 net/core/dev.c:3025
__dev_queue_xmit+0x1d95/0x25e0 net/core/dev.c:3525
dev_queue_xmit+0x18/0x20 net/core/dev.c:3558
pppoe_sendmsg+0x5cc/0x720 drivers/net/ppp/pppoe.c:906
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xce/0x110 net/socket.c:656
___sys_sendmsg+0x349/0x840 net/socket.c:2062
__sys_sendmmsg+0x152/0x3a0 net/socket.c:2152
SYSC_sendmmsg net/socket.c:2183 [inline]
SyS_sendmmsg+0x35/0x60 net/socket.c:2178
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c429
RSP: 002b:00007ff54e8f1c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007ff54e8f26d4 RCX: 000000000045c429
RDX: 04000000000000eb RSI: 000000002000d180 RDI: 0000000000000006
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007
R13: 00000000000008d2 R14: 00000000004cb32d R15: 0000000000000003
Kernel Offset: disabled
Rebooting in 86400 seconds..


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[syzbot]

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