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CVE-2026-89642 (GCVE-0-2026-89642)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:45 – Updated: 2026-09-13 06:24
VLAI
Title
cifs: call pagecache_isize_extended() in cifs_setsize() when extending
Summary
In the Linux kernel, the following vulnerability has been resolved: cifs: call pagecache_isize_extended() in cifs_setsize() when extending cifs_setsize() calls truncate_pagecache() but skips pagecache_isize_extended() on extension. truncate_setsize() shows the correct pattern: i_size_write(inode, newsize); if (newsize > oldsize) pagecache_isize_extended(inode, oldsize, newsize); truncate_pagecache(inode, newsize); pagecache_isize_extended() zeroes the tail of the page straddling old EOF. Without it, dirty bytes in that region can be written back to the server, exposing stale data in the newly extended range.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 12bafe32f09c0d24f5096154b59c347b9c6606e0 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < c510edb9734af1c274d18f4f31a471a166bbc7e8 (git)
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Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 7.2.4 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: call pagecache_isize_extended() in cifs_setsize() when extending\n\ncifs_setsize() calls truncate_pagecache() but skips\npagecache_isize_extended() on extension.  truncate_setsize() shows\nthe correct pattern:\n\n  i_size_write(inode, newsize);\n  if (newsize \u003e oldsize)\n      pagecache_isize_extended(inode, oldsize, newsize);\n  truncate_pagecache(inode, newsize);\n\npagecache_isize_extended() zeroes the tail of the page straddling old\nEOF.  Without it, dirty bytes in that region can be written back to\nthe server, exposing stale data in the newly extended range."
        }
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      "providerMetadata": {
        "dateUpdated": "2026-09-13T06:24:05.607Z",
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          "url": "https://git.kernel.org/stable/c/c510edb9734af1c274d18f4f31a471a166bbc7e8"
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    "cveId": "CVE-2026-89642",
    "datePublished": "2026-09-11T19:45:34.778Z",
    "dateReserved": "2026-09-11T19:38:34.741Z",
    "dateUpdated": "2026-09-13T06:24:05.607Z",
    "state": "PUBLISHED"
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}



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