CVE-2024-50279

Advisory lineage Upstream: 0 Downstream: 102
Modified
Published: 19 Nov 2024, 01:30
Last modified:11 May 2026, 20:49

Vulnerability Summary

Overall Risk (default)
medium
28/100
CVSS Score
7.1 HIGH
v3.1 (cve.org)
EPSS Score
0.02% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

19 Nov 2024, 01:30
Published
Vulnerability first disclosed
11 May 2026, 20:49
Last Modified
Vulnerability information updated

Description

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.

CVSS Metrics

  • v3.1•HIGH•Score: 7.1CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS Trends

Current EPSS score: 0.02%• Percentile: 4%

Techniques & Countermeasures

  • CWE-125•Out-of-bounds Read

    The product reads data past the end, or before the beginning, of the intended buffer.

Affected Systems

  • linux•linux

    ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 4fa4feb873cea0e9d6ff883b37cca6f33169d8b4 | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 8501e38dc9e0060814c4085815fc83da3e6d43bf | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < ee1f74925717ab36f6a091104c170639501ce818 | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < ff1dd8a04c30e8d4e2fd5c83198ca672eb6a9e7f | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 56507203e1b6127967ec2b51fb0b23a0d4af1334 | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < e57648ce325fa405fe6bbd0e6a618ced7c301a2d | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 3b02c40ff10fdf83cc545850db208de855ebe22c | ≥ f494a9c6b1b6dd9a9f21bbb75d9210d478eeb498, < 792227719725497ce10a8039803bec13f89f8910 | 3.13

  • linux•linux_kernel

    ≥ 3.13, < 4.19.324 | ≥ 4.20, < 5.4.286 | ≥ 5.5, < 5.10.230 | ≥ 5.11, < 5.15.172 | ≥ 5.16, < 6.1.117 | ≥ 6.2, < 6.6.61 | ≥ 6.7, < 6.11.8 | 6.12:rc1 | 6.12:rc2 | 6.12:rc3 | 6.12:rc4 | 6.12:rc5 | 6.12:rc6

References (10)