Description
In the Linux kernel, the following vulnerability has been resolved: procfs: fix possible double mmput() in do_procmap_query() When user provides incorrectly sized buffer for build ID for PROCMAP_QUERY we return with -ENAMETOOLONG error. After recent changes this condition happens later, after we unlocked mmap_lock/per-VMA lock and did mmput(), so original goto out is now wrong and will double-mmput() mm_struct. Fix by jumping further to clean up only vm_file and name_buf.
Affected products
linux: linux kernel
References7
- git.kernel.org/stable/c/61dc9f776705d6db6847c101b98fa4f0e9eb6fa3 Patch
- git.kernel.org/stable/c/8adaff87db143583e08eec4f4e7788f1ef8af94d Patch
- git.kernel.org/stable/c/90f5e87c9b75833b9ef3a4415b92c0247f28ab2f Patch
- git.kernel.org/stable/c/f9fe092084cd04deea18747f58a2304026e76aaa Patch
- access.redhat.com/security/cve/CVE-2026-43178
- bugzilla.redhat.com/show_bug.cgi?id=2467227
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43178…
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 3 · as of 13 November 2026
- CWE
- CWE-415CWE-1341
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