From: syzbot <syzbot+a4a3d526b4157113ec6a@syzkaller.appspotmail.com>
To: bfields@fieldses.org, jlayton@kernel.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk
Subject: KASAN: use-after-free Read in locks_delete_block
Date: Mon, 12 Nov 2018 12:34:02 -0800 [thread overview]
Message-ID: <000000000000222b58057a7d9f39@google.com> (raw)
Hello,
syzbot found the following crash on:
HEAD commit: 442b8cea2477 Add linux-next specific files for 20181109
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=115dbad5400000
kernel config: https://syzkaller.appspot.com/x/.config?x=2f72bdb11df9fbe8
dashboard link: https://syzkaller.appspot.com/bug?extid=a4a3d526b4157113ec6a
compiler: gcc (GCC) 8.0.1 20180413 (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+a4a3d526b4157113ec6a@syzkaller.appspotmail.com
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
==================================================================
BUG: KASAN: use-after-free in __list_del_entry_valid+0xf1/0x100
lib/list_debug.c:51
Read of size 8 at addr ffff88017eb47b70 by task syz-executor3/13461
CPU: 0 PID: 13461 Comm: syz-executor3 Not tainted 4.20.0-rc1-next-20181109+
#110
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+0x244/0x39d lib/dump_stack.c:113
print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
__list_del_entry_valid+0xf1/0x100 lib/list_debug.c:51
__list_del_entry include/linux/list.h:117 [inline]
list_del_init include/linux/list.h:159 [inline]
__locks_delete_block fs/locks.c:683 [inline]
locks_delete_block+0xce/0x3d0 fs/locks.c:716
locks_mandatory_area+0x48b/0x6a0 fs/locks.c:1398
rw_verify_area+0x2f2/0x360 fs/read_write.c:386
vfs_write+0x149/0x560 fs/read_write.c:544
ksys_write+0x101/0x260 fs/read_write.c:598
__do_sys_write fs/read_write.c:610 [inline]
__se_sys_write fs/read_write.c:607 [inline]
__x64_sys_write+0x73/0xb0 fs/read_write.c:607
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ff2e8194c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 0000000000000010 RSI: 0000000020000180 RDI: 0000000000000006
RBP: 000000000072c0e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff2e81956d4
R13: 00000000004c571f R14: 00000000004d9360 R15: 00000000ffffffff
The buggy address belongs to the page:
page:ffffea0005fad1c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 ffffea0005fad1c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88017eb47a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88017eb47a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> ffff88017eb47b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff88017eb47b80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88017eb47c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
---
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#bug-status-tracking for how to communicate with
syzbot.
next reply other threads:[~2018-11-12 20:34 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-12 20:34 syzbot [this message]
2018-11-13 10:37 ` Jeff Layton
2018-11-13 20:40 ` NeilBrown
2018-11-14 10:36 ` Jeff Layton
2018-11-15 22:45 ` Dmitry Vyukov
2018-11-15 23:41 ` NeilBrown
2018-11-16 20:37 ` Dmitry Vyukov
2018-11-17 13:33 ` Jeff Layton
2018-11-17 14:03 ` Bruce Fields
2018-11-20 6:57 ` Dmitry Vyukov
2018-11-20 11:08 ` Jeff Layton
2018-11-20 13:23 ` Dmitry Vyukov
2018-11-13 19:58 ` syzbot
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=000000000000222b58057a7d9f39@google.com \
--to=syzbot+a4a3d526b4157113ec6a@syzkaller.appspotmail.com \
--cc=bfields@fieldses.org \
--cc=jlayton@kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=syzkaller-bugs@googlegroups.com \
--cc=viro@zeniv.linux.org.uk \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®