PT-2024-33724 · Linux+2 · Linux Kernel+2
Stéphane Graber
+1
·
Published
2024-10-04
·
Updated
2026-05-26
·
CVE-2024-49880
CVSS v3.1
7.8
High
| Vector | AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Name of the Vulnerable Software and Affected Versions:
Linux kernel versions prior to 6.11.0+
Description:
The issue is related to an off-by-one error in the alloc flex gd() function in the ext4 filesystem. This error can cause the flex gd->resize bg to be bigger than flexbg size when adjusting resize bg. The problem can be reproduced with specific settings, such as o group = flexbg size * 2 * n and o size = (o group + 1) * group size. An example of the issue is when n=0 and flexbg size=16. The corresponding reproducer involves creating an ext4 filesystem, mounting it, and then resizing it. The issue was fixed by deleting the problematic plus 1 and adding a WARN ON ONCE() to prevent it from happening again.
Recommendations:
To resolve the issue, update the Linux kernel to a version later than 6.11.0+. As a temporary workaround, consider avoiding the use of the resize2fs command with specific settings that can trigger the off-by-one error. Restrict access to the vulnerable ext4 filesystem to minimize the risk of exploitation. Avoid using the
resize2fs command with the -s option to resize the filesystem until the issue is resolved.Exploit
Fix
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Weakness Enumeration
Related Identifiers
Affected Products
Linuxmint
Linux Kernel
Ubuntu