This is a note to let you know that I've just added the patch titled
udf: Fix a slab-out-of-bounds write bug in udf_find_entry()
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
udf-fix-a-slab-out-of-bounds-write-bug-in-udf_find_entry.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c8af247de385ce49afabc3bf1cf4fd455c94bfe8 Mon Sep 17 00:00:00 2001
From: ZhangPeng <zhangpeng362@xxxxxxxxxx>
Date: Wed, 9 Nov 2022 01:35:42 +0000
Subject: udf: Fix a slab-out-of-bounds write bug in udf_find_entry()
From: ZhangPeng <zhangpeng362@xxxxxxxxxx>
commit c8af247de385ce49afabc3bf1cf4fd455c94bfe8 upstream.
Syzbot reported a slab-out-of-bounds Write bug:
loop0: detected capacity change from 0 to 2048
==================================================================
BUG: KASAN: slab-out-of-bounds in udf_find_entry+0x8a5/0x14f0
fs/udf/namei.c:253
Write of size 105 at addr ffff8880123ff896 by task syz-executor323/3610
CPU: 0 PID: 3610 Comm: syz-executor323 Not tainted
6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS
Google 10/11/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
print_address_description+0x74/0x340 mm/kasan/report.c:284
print_report+0x107/0x1f0 mm/kasan/report.c:395
kasan_report+0xcd/0x100 mm/kasan/report.c:495
kasan_check_range+0x2a7/0x2e0 mm/kasan/generic.c:189
memcpy+0x3c/0x60 mm/kasan/shadow.c:66
udf_find_entry+0x8a5/0x14f0 fs/udf/namei.c:253
udf_lookup+0xef/0x340 fs/udf/namei.c:309
lookup_open fs/namei.c:3391 [inline]
open_last_lookups fs/namei.c:3481 [inline]
path_openat+0x10e6/0x2df0 fs/namei.c:3710
do_filp_open+0x264/0x4f0 fs/namei.c:3740
do_sys_openat2+0x124/0x4e0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_creat fs/open.c:1402 [inline]
__se_sys_creat fs/open.c:1396 [inline]
__x64_sys_creat+0x11f/0x160 fs/open.c:1396
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ffab0d164d9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe1a7e6bb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffab0d164d9
RDX: 00007ffab0d164d9 RSI: 0000000000000000 RDI: 0000000020000180
RBP: 00007ffab0cd5a10 R08: 0000000000000000 R09: 0000000000000000
R10: 00005555573552c0 R11: 0000000000000246 R12: 00007ffab0cd5aa0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
Allocated by task 3610:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x3d/0x60 mm/kasan/common.c:52
____kasan_kmalloc mm/kasan/common.c:371 [inline]
__kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:380
kmalloc include/linux/slab.h:576 [inline]
udf_find_entry+0x7b6/0x14f0 fs/udf/namei.c:243
udf_lookup+0xef/0x340 fs/udf/namei.c:309
lookup_open fs/namei.c:3391 [inline]
open_last_lookups fs/namei.c:3481 [inline]
path_openat+0x10e6/0x2df0 fs/namei.c:3710
do_filp_open+0x264/0x4f0 fs/namei.c:3740
do_sys_openat2+0x124/0x4e0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_creat fs/open.c:1402 [inline]
__se_sys_creat fs/open.c:1396 [inline]
__x64_sys_creat+0x11f/0x160 fs/open.c:1396
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
The buggy address belongs to the object at ffff8880123ff800
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 150 bytes inside of
256-byte region [ffff8880123ff800, ffff8880123ff900)
The buggy address belongs to the physical page:
page:ffffea000048ff80 refcount:1 mapcount:0 mapping:0000000000000000
index:0x0 pfn:0x123fe
head:ffffea000048ff80 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea00004b8500 dead000000000003 ffff888012041b40
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x0(),
pid 1, tgid 1 (swapper/0), ts 1841222404, free_ts 0
create_dummy_stack mm/page_owner.c:67 [inline]
register_early_stack+0x77/0xd0 mm/page_owner.c:83
init_page_owner+0x3a/0x731 mm/page_owner.c:93
kernel_init_freeable+0x41c/0x5d5 init/main.c:1629
kernel_init+0x19/0x2b0 init/main.c:1519
page_owner free stack trace missing
Memory state around the buggy address:
ffff8880123ff780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880123ff800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880123ff880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 06
^
ffff8880123ff900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880123ff980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Fix this by changing the memory size allocated for copy_name from
UDF_NAME_LEN(254) to UDF_NAME_LEN_CS0(255), because the total length
(lfi) of subsequent memcpy can be up to 255.
CC: stable@xxxxxxxxxxxxxxx
Reported-by: syzbot+69c9fdccc6dd08961d34@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 066b9cded00b ("udf: Use separate buffer for copying split names")
Signed-off-by: ZhangPeng <zhangpeng362@xxxxxxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
Link: https://lore.kernel.org/r/20221109013542.442790-1-zhangpeng362@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/udf/namei.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/udf/namei.c
+++ b/fs/udf/namei.c
@@ -237,7 +237,7 @@ static struct fileIdentDesc *udf_find_en
poffset - lfi);
else {
if (!copy_name) {
- copy_name = kmalloc(UDF_NAME_LEN,
+ copy_name = kmalloc(UDF_NAME_LEN_CS0,
GFP_NOFS);
if (!copy_name) {
fi = ERR_PTR(-ENOMEM);
Patches currently in stable-queue which might be from zhangpeng362@xxxxxxxxxx are
queue-4.14/udf-fix-a-slab-out-of-bounds-write-bug-in-udf_find_entry.patch
