Description
In the Linux kernel, the following vulnerability has been resolved: mm/slub: avoid accessing metadata when pointer is invalid in object_err() object_err() reports details of an object for further debugging, such as the freelist pointer, redzone, etc. However, if the pointer is invalid, attempting to access object metadata can lead to a crash since it does not point to a valid object. One known path to the crash is when alloc_consistency_checks() determines the pointer to the allocated object is invalid because of a freelist corruption, and calls object_err() to report it. The debug code should report and handle the corruption gracefully and not crash in the process. In case the pointer is NULL or check_valid_pointer() returns false for the pointer, only print the pointer value and skip accessing metadata.
Affected products
linux: linux kernel; debian: debian linux
References10
- git.kernel.org/stable/c/0ef7058b4dc6fcef622ac23b45225db57f17b83f Patch
- git.kernel.org/stable/c/1f0797f17927b5cad0fb7eced422f9a7c30a3191 Patch
- git.kernel.org/stable/c/3baa1da473e6e50281324ff1d332d1a07a3bb02e Patch
- git.kernel.org/stable/c/7e287256904ee796c9477e3ec92b07f236481ef3 Patch
- git.kernel.org/stable/c/872f2c34ff232af1e65ad2df86d61163c8ffad42 Patch
- git.kernel.org/stable/c/b4efccec8d06ceb10a7d34d7b1c449c569d53770 Patch
- git.kernel.org/stable/c/dda6ec365ab04067adae40ef17015db447e90736 Patch
- git.kernel.org/stable/c/f66012909e7bf383fcdc5850709ed5716073fdc4 Patch
- lists.debian.org/debian-lts-announce/2025/10/msg00007.html Third Party Advisory
- lists.debian.org/debian-lts-announce/2025/10/msg00008.html Third Party Advisory
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 9 November 2026
- CWE
- CWE-476
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