Hello,
syzbot found the following crash on:
HEAD commit: 68d7a45e Linux 4.14.113
git tree: linux-4.14.y
console output:
https://syzkaller.appspot.com/x/log.txt?x=14d68c62a00000
kernel config:
https://syzkaller.appspot.com/x/.config?x=dbf1fde4d7489e1c
dashboard link:
https://syzkaller.appspot.com/bug?extid=9217858d06d8c49f6936
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:
https://syzkaller.appspot.com/x/repro.syz?x=133abc60a00000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by:
syzbot+921785...@syzkaller.appspotmail.com
IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready
==================================================================
BUG: KASAN: stack-out-of-bounds in memset include/linux/string.h:332
[inline]
BUG: KASAN: stack-out-of-bounds in ax25_getname+0x55/0x7a0
net/ax25/af_ax25.c:1407
Write of size 72 at addr ffff8880870e7cf8 by task syz-executor.0/7195
CPU: 0 PID: 7195 Comm: syz-executor.0 Not tainted 4.14.113 #3
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+0x138/0x19c lib/dump_stack.c:53
print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351 [inline]
kasan_report mm/kasan/report.c:409 [inline]
kasan_report.cold+0xaf/0x2b5 mm/kasan/report.c:393
check_memory_region_inline mm/kasan/kasan.c:260 [inline]
check_memory_region+0x123/0x190 mm/kasan/kasan.c:267
memset+0x24/0x40 mm/kasan/kasan.c:285
memset include/linux/string.h:332 [inline]
ax25_getname+0x55/0x7a0 net/ax25/af_ax25.c:1407
get_raw_socket drivers/vhost/net.c:1039 [inline]
get_socket drivers/vhost/net.c:1096 [inline]
vhost_net_set_backend drivers/vhost/net.c:1131 [inline]
vhost_net_ioctl+0xe96/0x14c0 drivers/vhost/net.c:1307
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x458da9
RSP: 002b:00007ff6ac67ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000020d7c000 RSI: 000000004008af30 RDI: 0000000000000003
RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff6ac67b6d4
R13: 00000000004c37d7 R14: 00000000004d6cb0 R15: 00000000ffffffff
The buggy address belongs to the page:
page:ffffea00021c39c0 count:0 mapcount:0 mapping: (null) index:0x0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8880870e7c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
ffff8880870e7c80: f1 f1 f1 04 f2 04 f2 00 f2 f2 f2 00 f2 f2 f2 00
> ffff8880870e7d00: 00 00 00 00 00 04 f3 f3 f3 f3 f3 00 00 00 00 00
^
ffff8880870e7d80: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 f2 f2 f2
ffff8880870e7e00: 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 f3 f3 f3 f3
==================================================================
---
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