userfaultfd: fix a crash in UFFDIO_MOVE when PMD is a migration entry
3Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackepss 0.1%
exploitation probability
0.1%top 96% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved:
userfaultfd: fix a crash in UFFDIO_MOVE when PMD is a migration entry
When UFFDIO_MOVE encounters a migration PMD entry, it proceeds with
obtaining a folio and accessing it even though the entry is swp_entry_t.
Add the missing check and let split_huge_pmd() handle migration entries.
While at it also remove unnecessary folio check.
[surenb@google.com: remove extra folio check, per David]
Affected products
Linux · Linux