Paper/Archive/CVE-2026-64216

CVE-2026-64216

Linux Linux — netfs: Fix potential UAF in netfs_unlock_abandoned_read_pages()

Description · from the CVE record

In the Linux kernel, the following vulnerability has been resolved: netfs: Fix potential UAF in netfs_unlock_abandoned_read_pages() netfs_unlock_abandoned_read_pages(rreq) accesses the index of the folios it is wanting to unlock and compares that to rreq->no_unlock_folio so that it doesn't unlock a folio being read for netfs_perform_write() or netfs_write_begin(). However, given that netfs_unlock_abandoned_read_pages() is called _after_ NETFS_RREQ_IN_PROGRESS is cleared, the one folio that it's not allowed to dereference is the one specified by ->no_unlock_folio as ownership immediately reverts to the caller. Fix this by storing the folio pointer instead and using that rather than the index. Also fix netfs_unlock_read_folio() where the same applies.

Affected

ProductAffectedFixed inSource
Linuxee4cdf7ba857a894ad1650d6ab77669cbbfa329e – < d4ae8dba90b89e7bb4d1045d1cb26afbaf13ee5cd4ae8dba90b89e7bb4d1045d1cb26afbaf13ee5cCNA
Linuxee4cdf7ba857a894ad1650d6ab77669cbbfa329e – < 6080fa3ecfbb4448a3b47368629534c09b6ec7506080fa3ecfbb4448a3b47368629534c09b6ec750CNA
Linuxee4cdf7ba857a894ad1650d6ab77669cbbfa329e – < 3866d015f33aeedf81338dd99154703bef33faef3866d015f33aeedf81338dd99154703bef33faefCNA
Linuxee4cdf7ba857a894ad1650d6ab77669cbbfa329e – < dbe556972100fabb8e5a1b3d2163831ff07b1e8edbe556972100fabb8e5a1b3d2163831ff07b1e8eCNA
Linux6.126.12.106CNA

Scores by source

Linux (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

refgit.kernel.org/stable/c/d4ae8dba90b89e7bb4d1045d1cb26afbaf13ee5crefgit.kernel.org/stable/c/6080fa3ecfbb4448a3b47368629534c09b6ec750refgit.kernel.org/stable/c/3866d015f33aeedf81338dd99154703bef33faefrefgit.kernel.org/stable/c/dbe556972100fabb8e5a1b3d2163831ff07b1e8e