What’s Vulnerable › Vulnerabilities

CVE-2026-98223: mm: filemap: retain mapped dropbehind folios

• Severity: unknown
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-06 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: mm: filemap: retain mapped dropbehind folios Fault-around can map ready dropbehind folios without going through the normal page-cache lookup that clears dropbehind. A mapping represents a competing cached user, so retain the folio instead of forcibly unmapping it when writeback completes. For a mapped folio, folio_unmap_invalidate() can call unmap_mapping_folio(), which takes i_mmap_rwsem and may sleep. Retaining mapped folios avoids this path when folio_end_dropbehind() runs in non-preemptible task context. Tal was able to trigger a sleeping-in-atomic warning due to this [1]. Unmapped dropbehind folios continue through the existing invalidation path.

Affected products

• Linux kernel: 6.14 — fixed in 7.3

How to fix

Upgrade to a fixed version: Linux kernel 7.3. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/2897601dffe576fcd87a4259102f41f7fb0cbfc8
• https://git.kernel.org/stable/c/77c0fade37c80e8aa16ac048a9828249055e3f66
• https://git.kernel.org/stable/c/848d2ce2fce15fbdc083fbf9691bfa72911033c4

Get alerted when CVE-2026-98223 or the next vulnerability affects your stack