CVE-2025-39902

Vulnerability 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.

CVSS Score

Affected Products

Related Weaknesses (CWE)

References

• https://git.kernel.org/stable/c/0ef7058b4dc6fcef622ac23b45225db57f17b83fPatch
• https://git.kernel.org/stable/c/1f0797f17927b5cad0fb7eced422f9a7c30a3191Patch
• https://git.kernel.org/stable/c/3baa1da473e6e50281324ff1d332d1a07a3bb02ePatch
• https://git.kernel.org/stable/c/7e287256904ee796c9477e3ec92b07f236481ef3Patch
• https://git.kernel.org/stable/c/872f2c34ff232af1e65ad2df86d61163c8ffad42Patch
• https://git.kernel.org/stable/c/b4efccec8d06ceb10a7d34d7b1c449c569d53770Patch
• https://git.kernel.org/stable/c/dda6ec365ab04067adae40ef17015db447e90736Patch
• https://git.kernel.org/stable/c/f66012909e7bf383fcdc5850709ed5716073fdc4Patch
• https://lists.debian.org/debian-lts-announce/2025/10/msg00007.htmlThird Party Advisory
• https://lists.debian.org/debian-lts-announce/2025/10/msg00008.htmlThird Party Advisory