In the Linux kernel, the following vulnerability has been resolved:
dm cache: fix potential out-of-bounds access on the first resume
Out-of-bounds access occurs if the fast device is expanded unexpectedly
before the first-time resume of the cache table. This happens because
expanding the fast device requires reloading the cache table for
cache_create to allocate new in-core data structures that fit the new
size, and the check in cache_preresume is not performed during the
first resume, leading to the issue.
Reproduce steps:
1. prepare component devices:
dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"
dmsetup create cdata --table "0 65536 linear /dev/sdc 8192"
dmsetup create corig --table "0 524288 linear /dev/sdc 262144"
dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct
2. load a cache table of 512 cache blocks, and deliberately expand the
fast device before resuming the cache, making the in-core data
structures inadequate.
dmsetup create cache --notable
dmsetup reload cache --table "0 524288 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"
dmsetup reload cdata --table "0 131072 linear /dev/sdc 8192"
dmsetup resume cdata
dmsetup resume cache
3. suspend the cache to write out the in-core dirty bitset and hint
array, leading to out-of-bounds access to the dirty bitset at offset
0x40:
dmsetup suspend cache
KASAN reports:
BUG: KASAN: vmalloc-out-of-bounds in is_dirty_callback+0x2b/0x80
Read of size 8 at addr ffffc90000085040 by task dmsetup/90
(...snip...)
The buggy address belongs to the virtual mapping at
[ffffc90000085000, ffffc90000087000) created by:
cache_ctr+0x176a/0x35f0
(...snip...)
Memory state around the buggy address:
ffffc90000084f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc90000084f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
>ffffc90000085000: 00 00 00 00 00 00 00 00 f8 f8 f8 f8 f8 f8 f8 f8
^
ffffc90000085080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc90000085100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
Fix by checking the size change on the first resume.
References
Configurations
Configuration 1 (hide)
|
History
27 Nov 2024, 16:00
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://git.kernel.org/stable/c/036dd6e3d2638103e0092864577ea1d091466b86 - Patch | |
| References | () https://git.kernel.org/stable/c/13ed3624c6ef283acefa4cc42cc8ae54fd4391a4 - Patch | |
| References | () https://git.kernel.org/stable/c/2222b0929d00e2d13732b799b63be391b5de4492 - Patch | |
| References | () https://git.kernel.org/stable/c/483b7261b35a9d369082ab298a6670912243f0be - Patch | |
| References | () https://git.kernel.org/stable/c/c0ade5d98979585d4f5a93e4514c2e9a65afa08d - Patch | |
| References | () https://git.kernel.org/stable/c/c52ec00cb2f9bebfada22edcc0db385b910a1cdb - Patch | |
| References | () https://git.kernel.org/stable/c/e492f71854ce03474d49e87fd98b8df1f7cd1d2d - Patch | |
| References | () https://git.kernel.org/stable/c/fdef3b94dfebd57e3077a578b6e309a2bb6fa688 - Patch | |
| First Time |
Linux linux Kernel
Linux |
|
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc6:*:*:*:*:*:* |
|
| CWE | CWE-125 | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.1 |
19 Nov 2024, 21:57
| Type | Values Removed | Values Added |
|---|---|---|
| Summary |
|
19 Nov 2024, 02:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2024-11-19 02:16
Updated : 2024-11-27 16:00
NVD link : CVE-2024-50278
Mitre link : CVE-2024-50278
CVE.ORG link : CVE-2024-50278
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-125
Out-of-bounds Read