CVE-2022-49699
Summary
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.
Impact & exploitability
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected products we track (1)
Recommendation
Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.
Official patch: https://git.kernel.org/stable/c/a66f131d30e53000f08301776bf85c912ef47aad ↗