CVE-2026-43178 (GCVE-0-2026-43178)

Vulnerability from cvelistv5 – Published: 2026-05-06 11:27 – Updated: 2026-05-08 12:40
VLAI?
Title
procfs: fix possible double mmput() in do_procmap_query()
Summary
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.
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: b9b97e6aeb534315f9646b2090d1a5024c6a4e82 , < f9fe092084cd04deea18747f58a2304026e76aaa (git)
Affected: cbc03ce3e6ce7e21214c3f02218213574c1a2d08 , < 8adaff87db143583e08eec4f4e7788f1ef8af94d (git)
Affected: b5cbacd7f86f4f62b8813688c8e73be94e8e1951 , < 90f5e87c9b75833b9ef3a4415b92c0247f28ab2f (git)
Affected: b5cbacd7f86f4f62b8813688c8e73be94e8e1951 , < 61dc9f776705d6db6847c101b98fa4f0e9eb6fa3 (git)
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    Linux Linux Affected: 6.19
Unaffected: 0 , < 6.19 (semver)
Unaffected: 6.12.75 , ≤ 6.12.* (semver)
Unaffected: 6.18.16 , ≤ 6.18.* (semver)
Unaffected: 6.19.6 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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