In the Linux kernel, the following vulnerability has been resolved:
dm cache: fix out-of-bounds access to the dirty bitset when resizing
dm-cache checks the dirty bits of the cache blocks to be dropped when
shrinking the fast device, but an index bug in bitset iteration causes
out-of-bounds access.
Reproduce steps:
1. create a cache device of 1024 cache blocks (128 bytes dirty bitset)
dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"
dmsetup create cdata --table "0 131072 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
dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"
2. shrink the fast device to 512 cache blocks, triggering out-of-bounds
access to the dirty bitset (offset 0x80)
dmsetup suspend cache
dmsetup reload cdata --table "0 65536 linear /dev/sdc 8192"
dmsetup resume cdata
dmsetup resume cache
KASAN reports:
BUG: KASAN: vmalloc-out-of-bounds in cache_preresume+0x269/0x7b0
Read of size 8 at addr ffffc900000f3080 by task dmsetup/131
(...snip...)
The buggy address belongs to the virtual mapping at
[ffffc900000f3000, ffffc900000f5000) created by:
cache_ctr+0x176a/0x35f0
(...snip...)
Memory state around the buggy address:
ffffc900000f2f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc900000f3000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc900000f3080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
^
ffffc900000f3100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc900000f3180: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
Fix by making the index post-incremented.
References
Configurations
Configuration 1 (hide)
|
History
27 Nov 2024, 16:01
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Linux linux Kernel
Linux |
|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.1 |
| References | () https://git.kernel.org/stable/c/56507203e1b6127967ec2b51fb0b23a0d4af1334 - Patch | |
| References | () https://git.kernel.org/stable/c/792227719725497ce10a8039803bec13f89f8910 - Patch | |
| References | () https://git.kernel.org/stable/c/8501e38dc9e0060814c4085815fc83da3e6d43bf - Patch | |
| References | () https://git.kernel.org/stable/c/3b02c40ff10fdf83cc545850db208de855ebe22c - Patch | |
| References | () https://git.kernel.org/stable/c/e57648ce325fa405fe6bbd0e6a618ced7c301a2d - Patch | |
| References | () https://git.kernel.org/stable/c/ee1f74925717ab36f6a091104c170639501ce818 - Patch | |
| References | () https://git.kernel.org/stable/c/4fa4feb873cea0e9d6ff883b37cca6f33169d8b4 - Patch | |
| References | () https://git.kernel.org/stable/c/ff1dd8a04c30e8d4e2fd5c83198ca672eb6a9e7f - Patch | |
| CWE | CWE-125 | |
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc4:*:*:*:*:*:* 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:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc6:*:*:*:*:*:* |
19 Nov 2024, 02:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2024-11-19 02:16
Updated : 2024-11-27 16:01
NVD link : CVE-2024-50279
Mitre link : CVE-2024-50279
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-125
Out-of-bounds Read