KASAN: slab-out-of-bounds Read in squashfs_get

KASAN: slab-out-of-bounds Read in squashfs_get_id
Status: upstream: reported C repro on 2020/09/25 14:48
Reported-by: syzbot+8e28bba73ed1772a6802@syzkaller.appspotmail.com
First crash: 127d, last: 5d12h

Cause bisection: failed (bisect log)

similar bugs (2):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-4.19	KASAN: slab-out-of-bounds Read in squashfs_get_id	C			48	6d02h	125d	0/1	upstream: reported C repro on 2020/09/24 08:21
linux-4.14	KASAN: slab-out-of-bounds Read in squashfs_get_id	C			11	12d	127d	0/1	upstream: reported C repro on 2020/09/22 07:00

Patch testing requests:
Created	Duration	User	Patch	Repo	Result
2020/10/14 06:53	17m	foxhlchen@gmail.com	patch	git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git d3d45f82	OK
2020/10/07 15:48	9m	foxhlchen@gmail.com		upstream	report log

Sample crash report:

==================================================================
BUG: KASAN: slab-out-of-bounds in squashfs_get_id+0x1ae/0x1d0 fs/squashfs/id.c:38
Read of size 8 at addr ffff888014da0890 by task syz-executor820/8457

CPU: 1 PID: 8457 Comm: syz-executor820 Not tainted 5.10.0-rc7-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+0x107/0x163 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x4c8 mm/kasan/report.c:385
 __kasan_report mm/kasan/report.c:545 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:562
 squashfs_get_id+0x1ae/0x1d0 fs/squashfs/id.c:38
 squashfs_new_inode fs/squashfs/inode.c:51 [inline]
 squashfs_read_inode+0x1b4/0x1b40 fs/squashfs/inode.c:120
 squashfs_fill_super+0x1140/0x23b0 fs/squashfs/super.c:310
 get_tree_bdev+0x421/0x740 fs/super.c:1344
 vfs_get_tree+0x89/0x2f0 fs/super.c:1549
 do_new_mount fs/namespace.c:2875 [inline]
 path_mount+0x13ad/0x20c0 fs/namespace.c:3205
 do_mount fs/namespace.c:3218 [inline]
 __do_sys_mount fs/namespace.c:3426 [inline]
 __se_sys_mount fs/namespace.c:3403 [inline]
 __x64_sys_mount+0x27f/0x300 fs/namespace.c:3403
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x446d1a
Code: b8 08 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd ad fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 da ad fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007ffec71d7408 EFLAGS: 00000293 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffec71d7460 RCX: 0000000000446d1a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffec71d7420
RBP: 00007ffec71d7420 R08: 00007ffec71d7460 R09: 00007ffe00000015
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 0000000000000004 R14: 0000000000000003 R15: 0000000000000003

Allocated by task 6443:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:461
 kmalloc include/linux/slab.h:557 [inline]
 kzalloc include/linux/slab.h:664 [inline]
 lsm_cred_alloc security/security.c:533 [inline]
 security_prepare_creds+0x10e/0x190 security/security.c:1632
 prepare_creds+0x4bd/0x6c0 kernel/cred.c:285
 access_override_creds fs/open.c:353 [inline]
 do_faccessat+0x3d7/0x820 fs/open.c:417
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff888014da0870
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 24 bytes to the right of
 8-byte region [ffff888014da0870, ffff888014da0878)
The buggy address belongs to the page:
page:00000000ac3d44c7 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14da0
flags: 0xfff00000000200(slab)
raw: 00fff00000000200 ffffea00006eb080 0000001700000017 ffff888010041c80
raw: 0000000000000000 0000000080660066 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888014da0780: fa fc fc fc fc fa fc fc fc fc fa fc fc fc fc 00
 ffff888014da0800: fc fc fc fc fa fc fc fc fc 00 fc fc fc fc fb fc
>ffff888014da0880: fc fc fc fa fc fc fc fc fb fc fc fc fc 00 fc fc
                         ^
 ffff888014da0900: fc fc fa fc fc fc fc fa fc fc fc fc 00 fc fc fc
 ffff888014da0980: fc fb fc fc fc fc 00 fc fc fc fc 00 fc fc fc fc
==================================================================

Crashes (68):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Maintainers
ci-upstream-kasan-gce-root	2020/12/08 08:46	upstream	cd796ed3	51a9082e	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/12/05 10:18	upstream	e87297fa	20366b87	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/12/03 16:03	upstream	34816d20	e6b0d314	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/11/07 10:44	upstream	bf3e7628	64069d48	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/11/06 10:49	upstream	521b619a	64069d48	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/11/06 05:49	upstream	521b619a	64069d48	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/11/06 03:11	upstream	521b619a	64069d48	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/10/13 01:58	upstream	bbf5c979	d32b0bbf	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/10/09 02:17	upstream	3d006ee4	92390980	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/10/03 16:38	upstream	d3d45f82	2653fa43	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/10/02 06:47	upstream	fcadab74	9602ddf4	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/09/25 10:13	upstream	171d4ff7	54289b08	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/09/21 14:57	upstream	ba4f184e	9e1fa68e	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/11/30 01:05	linux-next	6174f052	a0092f9d	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/11/27 16:49	linux-next	6147c83f	5018c946	.config	log	report	syz	C		linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2021/01/22 01:03	upstream	9791581c	d4f4eca5	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2021/01/21 08:30	upstream	75439bc4	d4f4eca5	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2021/01/14 07:21	upstream	65f0d241	269d24e8	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2021/01/11 23:17	upstream	7c53f6b6	2c1f2513	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2021/01/11 19:16	upstream	7c53f6b6	2c1f2513	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/12/15 23:58	upstream	148842c9	97183ed7	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/12/06 13:26	upstream	33256ce1	f12ba0c5	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/12/03 17:46	upstream	34816d20	e6b0d314	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/11/28 08:25	upstream	99c710c4	486f93ef	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/11/26 16:29	upstream	fa02fcd9	1d2b823e	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/11/26 04:15	upstream	fa02fcd9	2f1cec62	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/11/24 15:00	upstream	d5beb314	1ab681a4	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/11/24 08:14	upstream	d5beb314	1ab681a4	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/11/23 05:37	upstream	a349e4c6	0d27f508	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/11/23 05:36	upstream	a349e4c6	0d27f508	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-qemu-upstream	2020/11/06 00:37	upstream	521b619a	64069d48	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/10/14 17:57	upstream	b5fc7a89	fc7735a2	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/10/12 16:37	upstream	bbf5c979	d32b0bbf	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/10/01 22:10	upstream	fcadab74	9602ddf4	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/09/30 15:10	upstream	02de58b2	8516f6d3	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/09/28 16:54	upstream	a1b8638b	6bfdbe89	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/09/27 04:10	upstream	eeddbe68	2d5ea0cb	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/09/27 03:26	upstream	eeddbe68	2d5ea0cb	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-qemu-upstream	2020/09/27 01:13	upstream	a1bffa48	5dd8aee8	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/09/26 04:30	upstream	171d4ff7	4a006f63	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-qemu-upstream	2020/09/25 13:22	upstream	171d4ff7	4a006f63	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/09/24 19:12	upstream	c9c9e6a4	54289b08	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/09/24 08:21	upstream	c9c9e6a4	54289b08	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/09/24 08:21	upstream	c9c9e6a4	54289b08	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/09/24 08:19	upstream	c9c9e6a4	54289b08	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/09/24 08:15	upstream	c9c9e6a4	54289b08	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-smack-root	2020/09/24 08:14	upstream	c9c9e6a4	54289b08	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-qemu-upstream	2020/09/24 08:10	upstream	c9c9e6a4	54289b08	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-selinux-root	2020/09/23 23:44	upstream	805c6d3c	287cd75a	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-kasan-gce-root	2020/09/21 14:41	upstream	ba4f184e	9e1fa68e	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-qemu-upstream-386	2020/10/20 12:22	upstream	270315b8	ff4a3345	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-qemu-upstream-386	2020/10/05 15:06	upstream	549738f1	1880b4a9	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-qemu-upstream-386	2020/10/04 01:08	upstream	22fbc037	1a3f9408	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-qemu-upstream-386	2020/09/28 22:10	upstream	a4d63c37	1b88c6d5	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2021/01/15 15:26	linux-next	b3a3cbde	65a7a854	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/12/18 03:59	linux-next	90cc8cf2	04201c06	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/12/03 23:45	linux-next	0eedceaf	e6b0d314	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/11/26 02:58	linux-next	62918e6f	2f1cec62	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/10/19 06:10	linux-next	b2926c10	fea47c01	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/09/27 13:12	linux-next	d1d2220c	5dd8aee8	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/09/24 08:15	linux-next	dcf2427b	54289b08	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/09/22 08:07	linux-next	b10b8ad8	9e1fa68e	.config	log	report			info	linux-kernel@vger.kernel.org, phillip@squashfs.org.uk