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.
Analysis and contextual insights are available on OpenCVE Cloud.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
Sign in to view the affected projects.
| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-4008-1 | linux-6.1 security update |
Debian DLA |
DLA-4075-1 | linux security update |
Debian DSA |
DSA-5818-1 | linux security update |
Ubuntu USN |
USN-7276-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7277-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7288-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7288-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7289-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7289-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7289-3 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7289-4 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7291-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7293-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7294-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7294-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7294-3 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7294-4 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7295-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7305-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7308-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7310-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7331-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7388-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7389-1 | Linux kernel (NVIDIA Tegra) vulnerabilities |
Ubuntu USN |
USN-7390-1 | Linux kernel (Xilinx ZynqMP) vulnerabilities |
Ubuntu USN |
USN-7393-1 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7401-1 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7413-1 | Linux kernel (IoT) vulnerabilities |
Ubuntu USN |
USN-7449-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7449-2 | Linux kernel (HWE) vulnerabilities |
Ubuntu USN |
USN-7450-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7451-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7452-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7453-1 | Linux kernel (Real-time) vulnerabilities |
Ubuntu USN |
USN-7458-1 | Linux kernel (IBM) vulnerabilities |
Ubuntu USN |
USN-7468-1 | Linux kernel (Azure, N-Series) vulnerabilities |
Ubuntu USN |
USN-7523-1 | Linux kernel (Raspberry Pi Real-time) vulnerabilities |
Ubuntu USN |
USN-7524-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-7539-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-7540-1 | Linux kernel (Raspberry Pi) vulnerabilities |
Mon, 03 Nov 2025 23:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Mon, 03 Nov 2025 21:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Wed, 01 Oct 2025 21:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Thu, 19 Dec 2024 02:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
threat_severity
|
threat_severity
|
Wed, 27 Nov 2024 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| Weaknesses | CWE-125 | |
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc6:*:*:*:*:*:* |
|
| Vendors & Products |
Linux
Linux linux Kernel |
|
| Metrics |
cvssV3_1
|
cvssV3_1
|
Fri, 22 Nov 2024 14:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Tue, 19 Nov 2024 01:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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. | |
| Title | dm cache: fix out-of-bounds access to the dirty bitset when resizing | |
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-05-11T20:49:03.406Z
Reserved: 2024-10-21T19:36:19.983Z
Link: CVE-2024-50279
Updated: 2025-11-03T22:27:58.416Z
Status : Modified
Published: 2024-11-19T02:16:30.210
Modified: 2025-11-03T23:17:10.030
Link: CVE-2024-50279
OpenCVE Enrichment
No data.
Debian DLA
Debian DSA
Ubuntu USN