From: syzbot <syzbot+e869cfbeeae05d706b9c@syzkaller.appspotmail.com>
To: Jason@zx2c4.com, davem@davemloft.net, kuba@kernel.org,
linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
syzkaller-bugs@googlegroups.com, wireguard@lists.zx2c4.com
Subject: KASAN: use-after-free Read in wg_get_device_start
Date: Sun, 05 Jul 2020 23:22:14 -0700 [thread overview]
Message-ID: <00000000000049f07f05a9bfe509@google.com> (raw)
Hello,
syzbot found the following crash on:
HEAD commit: 7cc2a8ea Merge tag 'block-5.8-2020-07-01' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=123532a7100000
kernel config: https://syzkaller.appspot.com/x/.config?x=183dd243398ba7ec
dashboard link: https://syzkaller.appspot.com/bug?extid=e869cfbeeae05d706b9c
compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
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+e869cfbeeae05d706b9c@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: use-after-free in nla_get_u32 include/net/netlink.h:1541 [inline]
BUG: KASAN: use-after-free in lookup_interface drivers/net/wireguard/netlink.c:61 [inline]
BUG: KASAN: use-after-free in wg_get_device_start+0x2bc/0x2d0 drivers/net/wireguard/netlink.c:203
Read of size 4 at addr ffff88803b9c3818 by task syz-executor.3/15521
CPU: 1 PID: 15521 Comm: syz-executor.3 Not tainted 5.8.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1f0/0x31e lib/dump_stack.c:118
print_address_description+0x66/0x5a0 mm/kasan/report.c:383
__kasan_report mm/kasan/report.c:513 [inline]
kasan_report+0x132/0x1d0 mm/kasan/report.c:530
nla_get_u32 include/net/netlink.h:1541 [inline]
lookup_interface drivers/net/wireguard/netlink.c:61 [inline]
wg_get_device_start+0x2bc/0x2d0 drivers/net/wireguard/netlink.c:203
genl_start+0x390/0x570 net/netlink/genetlink.c:556
__netlink_dump_start+0x3d2/0x700 net/netlink/af_netlink.c:2343
genl_family_rcv_msg_dumpit net/netlink/genetlink.c:638 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:733 [inline]
genl_rcv_msg+0xb03/0xe00 net/netlink/genetlink.c:753
netlink_rcv_skb+0x190/0x3a0 net/netlink/af_netlink.c:2469
genl_rcv+0x24/0x40 net/netlink/genetlink.c:764
netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
netlink_unicast+0x786/0x940 net/netlink/af_netlink.c:1329
netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1918
sock_sendmsg_nosec net/socket.c:652 [inline]
sock_sendmsg net/socket.c:672 [inline]
____sys_sendmsg+0x519/0x800 net/socket.c:2352
___sys_sendmsg net/socket.c:2406 [inline]
__sys_sendmsg+0x2b1/0x360 net/socket.c:2439
do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb29
Code: Bad RIP value.
RSP: 002b:00007f1bd1266c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000502320 RCX: 000000000045cb29
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a32 R14: 00000000004cd184 R15: 00007f1bd12676d4
Allocated by task 15525:
save_stack mm/kasan/common.c:48 [inline]
set_track mm/kasan/common.c:56 [inline]
__kasan_kmalloc+0x103/0x140 mm/kasan/common.c:494
__kmalloc_reserve net/core/skbuff.c:142 [inline]
__alloc_skb+0xde/0x4f0 net/core/skbuff.c:210
alloc_skb include/linux/skbuff.h:1083 [inline]
netlink_alloc_large_skb net/netlink/af_netlink.c:1175 [inline]
netlink_sendmsg+0x7b2/0xd70 net/netlink/af_netlink.c:1893
sock_sendmsg_nosec net/socket.c:652 [inline]
sock_sendmsg net/socket.c:672 [inline]
____sys_sendmsg+0x519/0x800 net/socket.c:2352
___sys_sendmsg net/socket.c:2406 [inline]
__sys_sendmsg+0x2b1/0x360 net/socket.c:2439
do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Freed by task 15525:
save_stack mm/kasan/common.c:48 [inline]
set_track mm/kasan/common.c:56 [inline]
kasan_set_free_info mm/kasan/common.c:316 [inline]
__kasan_slab_free+0x114/0x170 mm/kasan/common.c:455
__cache_free mm/slab.c:3426 [inline]
kfree+0x10a/0x220 mm/slab.c:3757
skb_release_all net/core/skbuff.c:664 [inline]
__kfree_skb+0x56/0x1c0 net/core/skbuff.c:678
netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
netlink_unicast+0x78e/0x940 net/netlink/af_netlink.c:1329
netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1918
sock_sendmsg_nosec net/socket.c:652 [inline]
sock_sendmsg net/socket.c:672 [inline]
____sys_sendmsg+0x519/0x800 net/socket.c:2352
___sys_sendmsg net/socket.c:2406 [inline]
__sys_sendmsg+0x2b1/0x360 net/socket.c:2439
do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359
entry_SYSCALL_64_after_hwframe+0x44/0xa9
The buggy address belongs to the object at ffff88803b9c3800
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 24 bytes inside of
1024-byte region [ffff88803b9c3800, ffff88803b9c3c00)
The buggy address belongs to the page:
page:ffffea0000ee70c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea0001859248 ffffea0000e02ec8 ffff8880aa400c40
raw: 0000000000000000 ffff88803b9c3000 0000000100000002 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88803b9c3700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88803b9c3780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88803b9c3800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88803b9c3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88803b9c3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
reply other threads:[~2020-07-06 6:22 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=00000000000049f07f05a9bfe509@google.com \
--to=syzbot+e869cfbeeae05d706b9c@syzkaller.appspotmail.com \
--cc=Jason@zx2c4.com \
--cc=davem@davemloft.net \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=syzkaller-bugs@googlegroups.com \
--cc=wireguard@lists.zx2c4.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.