filemap: Handle sibling entries in filemap_get_read_batch() (Linux Linux)

CVE-2022-49699
MEDIUM 5.5

At a glance

Source
NVD
EPSS
EPSS 0.23 % · percentile 14 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: filemap: Handle sibling entries in filemap_get_read_batch() If a read races with an invalidation followed by another read, it is possible for a folio to be replaced with a higher-order folio. If that happens, we'll see a sibling entry for the new folio in the next iteration of the loop. This manifests as a NULL pointer dereference while holding the RCU read lock. Handle this by simply returning. The next call will find the new folio and handle it correctly. The other ways of handling this rare race are more complex and it's just not worth it.

Weaknesses (CWE)

  • CWE-476 — NULL Pointer Dereference

References

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HNVD · nvd@nist.gov (Primary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected cbd59c48ae2bcadc4a7599c29cf32fd3f9b78251 < a66f131d30e53000f08301776bf85c912ef47aad ; affected cbd59c48ae2bcadc4a7599c29cf32fd3f9b78251 < cb995f4eeba9d268fd4b56c2423ad6c1d1ea1b82
Linux · Linuxaffected 5.12 ; unaffected 0 < 5.12 ; unaffected 5.18.8 ≤ 5.18.* ; unaffected 5.19 ≤ *

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD