KASAN: stack-out-of-bounds Write in ax25

KASAN: stack-out-of-bounds Write in ax25_getname

Status: auto-obsoleted due to no activity on 2022/12/20 01:24
Subsystems: hams
[Documentation on labels]
Reported-by: syzbot+6a29097222b4d3b8617c@syzkaller.appspotmail.com
First crash: 2281d, last: 1862d

Fix bisection: failed (error log, bisect log)

▶ ▼ Discussions (3)

Title	Replies (including bot)	Last reply
KASAN: stack-out-of-bounds Write in ax25_getname	0 (3)	2020/02/17 04:45
Reminder: 3 open syzbot bugs in "net/ax25" subsystem	3 (3)	2019/07/24 08:01
Reminder: 4 open syzbot bugs in "net/ax25" subsystem	1 (1)	2019/06/27 03:47

▶ ▼ Similar bugs (2)

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-4.19	KASAN: stack-out-of-bounds Write in ax25_getname	C		done	4	1864d	2160d	1/1	fixed on 2020/03/17 21:24
linux-4.14	KASAN: stack-out-of-bounds Write in ax25_getname	C		done	4	1865d	2160d	1/1	fixed on 2020/03/17 21:24

▶ ▼ Last patch testing requests (10)


Created	Duration	User	Repo	Result
2022/12/19 23:31	22m	retest repro	upstream	OK log
2022/12/19 23:31	21m	retest repro	linux-next	OK log
2022/12/19 17:31	19m	retest repro	linux-next	OK log
2022/12/19 14:31	19m	retest repro	linux-next	OK log
2022/12/19 10:31	20m	retest repro	linux-next	OK log
2022/09/15 07:29	17m	retest repro	upstream	OK log
2022/09/15 04:29	15m	retest repro	upstream	OK log
2022/09/15 01:29	16m	retest repro	upstream	OK log
2022/09/14 22:29	17m	retest repro	upstream	OK log
2022/09/14 19:29	16m	retest repro	upstream	OK log

▶ ▼ Fix bisection attempts (3)


Created	Duration	User	Repo	Result
2020/01/03 17:38	13m	bisect fix	upstream	error job log
2019/11/09 21:12	21m	bisect fix	upstream	OK (0) job log log
2019/08/19 09:32	21m	bisect fix	upstream	OK (0) job log log

Sample crash report:

==================================================================
BUG: KASAN: stack-out-of-bounds in memset include/linux/string.h:366 [inline]
BUG: KASAN: stack-out-of-bounds in ax25_getname+0x58/0x7a0 net/ax25/af_ax25.c:1405
Write of size 72 at addr ffffc900020c7e00 by task syz-executor973/10753

CPU: 1 PID: 10753 Comm: syz-executor973 Not tainted 5.6.0-rc2-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+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:641
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192
 memset+0x24/0x40 mm/kasan/common.c:108
 memset include/linux/string.h:366 [inline]
 ax25_getname+0x58/0x7a0 net/ax25/af_ax25.c:1405
 get_raw_socket drivers/vhost/net.c:1433 [inline]
 get_socket drivers/vhost/net.c:1489 [inline]
 vhost_net_set_backend drivers/vhost/net.c:1524 [inline]
 vhost_net_ioctl+0x1213/0x1960 drivers/vhost/net.c:1715
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x123/0x180 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440259
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffb9862cc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440259
RDX: 0000000020f1dff8 RSI: 000000004008af30 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000401ae0
R13: 0000000000401b70 R14: 0000000000000000 R15: 0000000000000000


addr ffffc900020c7e00 is located in stack of task syz-executor973/10753 at offset 128 in frame:
 vhost_net_ioctl+0x0/0x1960 drivers/vhost/net.c:386

this frame has 4 objects:
 [48, 52) 'r'
 [64, 72) 'features'
 [96, 104) 'backend'
 [128, 180) 'uaddr'

Memory state around the buggy address:
 ffffc900020c7d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900020c7d80: f1 f1 f1 f1 f1 f1 04 f2 00 f2 f2 f2 00 f2 f2 f2
>ffffc900020c7e00: 00 00 00 00 00 00 04 f3 f3 f3 f3 f3 00 00 00 00
                                     ^
 ffffc900020c7e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900020c7f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (21):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	Manager
2020/02/18 08:46	upstream	11a48a5a18c6	1ce142dc	.config	console log	report	syz	C	ci-upstream-kasan-gce-selinux-root
2020/02/17 04:44	upstream	11a48a5a18c6	1f448cd6	.config	console log	report	syz	C	ci-upstream-kasan-gce-root
2019/11/18 09:42	upstream	cbb104f91dfe	d5696d51	.config	console log	report	syz		ci-upstream-kasan-gce-selinux-root
2019/11/16 03:23	upstream	eb70e26cd79d	cdac920b	.config	console log	report	syz		ci-upstream-kasan-gce-root
2019/04/24 13:08	upstream	ba25b50d582f	8e3c52b1	.config	console log	report	syz		ci-upstream-kasan-gce-smack-root
2019/04/24 07:37	upstream	7142eaa58b49	4d3d6a50	.config	console log	report	syz		ci-upstream-kasan-gce-root
2019/04/24 07:16	upstream	7142eaa58b49	4d3d6a50	.config	console log	report	syz		ci-upstream-kasan-gce-selinux-root
2019/02/14 17:38	upstream	1f947a7a011f	76dd003f	.config	console log	report	syz		ci-upstream-kasan-gce-root
2019/02/14 10:02	upstream	1f947a7a011f	6a46f448	.config	console log	report	syz		ci-upstream-kasan-gce-smack-root
2019/02/14 09:32	upstream	1f947a7a011f	6a46f448	.config	console log	report	syz		ci-upstream-kasan-gce-selinux-root
2018/12/27 01:54	upstream	eed9688f8513	e747ec98	.config	console log	report	syz		ci-upstream-kasan-gce-root
2018/12/26 16:22	upstream	5694cecdb092	8a41a0ad	.config	console log	report	syz		ci-upstream-kasan-gce-selinux-root
2018/12/25 19:02	upstream	8fe28cb58bcb	8a41a0ad	.config	console log	report	syz		ci-upstream-kasan-gce-smack-root
2019/12/04 17:38	linux-next	c7c32c43e831	b2088328	.config	console log	report	syz		ci-upstream-linux-next-kasan-gce-root
2019/04/24 07:38	linux-next	76c938fcaa4b	4d3d6a50	.config	console log	report	syz		ci-upstream-linux-next-kasan-gce-root
2019/02/14 09:59	linux-next	b3418f8bddf4	6a46f448	.config	console log	report	syz		ci-upstream-linux-next-kasan-gce-root
2018/12/28 14:53	linux-next	6a1d293238c1	fc6ae81a	.config	console log	report	syz		ci-upstream-linux-next-kasan-gce-root
2019/08/30 12:33	upstream	6525771f58cb	fd37b39e	.config	console log	report			ci-upstream-kasan-gce-selinux-root
2019/04/24 06:47	upstream	7142eaa58b49	4d3d6a50	.config	console log	report			ci-upstream-kasan-gce-selinux-root
2019/02/14 09:06	upstream	1f947a7a011f	6a46f448	.config	console log	report			ci-upstream-kasan-gce-selinux-root
2018/12/25 18:09	upstream	8fe28cb58bcb	8a41a0ad	.config	console log	report			ci-upstream-kasan-gce-smack-root

* ~~Struck through~~ repros no longer work on HEAD.