ghsa-wmpp-p439-v4x7
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
ceph: fix crash after fscrypt_encrypt_pagecache_blocks() error
The function move_dirty_folio_in_page_array() was created by commit ce80b76dd327 ("ceph: introduce ceph_process_folio_batch() method") by moving code from ceph_writepages_start() to this function.
This new function is supposed to return an error code which is checked by the caller (now ceph_process_folio_batch()), and on error, the caller invokes redirty_page_for_writepage() and then breaks from the loop.
However, the refactoring commit has gone wrong, and it by accident, it always returns 0 (= success) because it first NULLs the pointer and then returns PTR_ERR(NULL) which is always 0. This means errors are silently ignored, leaving NULL entries in the page array, which may later crash the kernel.
The simple solution is to call PTR_ERR() before clearing the pointer.
{
"affected": [],
"aliases": [
"CVE-2025-39878"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-23T06:15:47Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: fix crash after fscrypt_encrypt_pagecache_blocks() error\n\nThe function move_dirty_folio_in_page_array() was created by commit\nce80b76dd327 (\"ceph: introduce ceph_process_folio_batch() method\") by\nmoving code from ceph_writepages_start() to this function.\n\nThis new function is supposed to return an error code which is checked\nby the caller (now ceph_process_folio_batch()), and on error, the\ncaller invokes redirty_page_for_writepage() and then breaks from the\nloop.\n\nHowever, the refactoring commit has gone wrong, and it by accident, it\nalways returns 0 (= success) because it first NULLs the pointer and\nthen returns PTR_ERR(NULL) which is always 0. This means errors are\nsilently ignored, leaving NULL entries in the page array, which may\nlater crash the kernel.\n\nThe simple solution is to call PTR_ERR() before clearing the pointer.",
"id": "GHSA-wmpp-p439-v4x7",
"modified": "2025-09-23T06:30:27Z",
"published": "2025-09-23T06:30:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39878"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/249e0a47cdb46bb9eae65511c569044bd8698d7d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/dd1616ecbea920d228c56729461ed223cc501425"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
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Nomenclature
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