CVE-2022-49348

medium
Published 2022-11-15 ยท Modified 2022-11-15
CVSS v3
โ€”
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
5.5

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: filter out EXT4_FC_REPLAY from on-disk superblock field s_state The EXT4_FC_REPLAY bit in sbi->s_mount_state is used to indicate that we are in the middle of replay the fast commit journal. This was actually a mistake, since the sbi->s_mount_info is initialized from es->s_state. Arguably s_mount_state is misleadingly named, but the name is historical --- s_mount_state and s_state dates back to ext2. What should have been used is the ext4_{set,clear,test}_mount_flag() inline functions, which sets EXT4_MF_* bits in sbi->s_mount_flags. The problem with using EXT4_FC_REPLAY is that a maliciously corrupted superblock could result in EXT4_FC_REPLAY getting set in s_mount_state. This bypasses some sanity checks, and this can trigger a BUG() in ext4_es_cache_extent(). As a easy-to-backport-fix, filter out the EXT4_FC_REPLAY bit for now. We should eventually transition away from EXT4_FC_REPLAY to something like EXT4_MF_REPLAY.

Predictions

Exploit likelihood
20%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ€” if you've already worked around this in production โ€” publish your fix to the community-verified tier.

โœš Propose a mitigation on Community โ†’ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

suse SUSE Affected 1 release
VersionStatusFixed in
โ€” Affected โ€”
debian Debian Fixed 5 releases
VersionStatusFixed in
trixie Fixed 5.18.5-1
sid Fixed 5.18.5-1
forky Fixed 5.18.5-1
bullseye Fixed 5.10.127-1
bookworm Fixed 5.18.5-1
redhat Red Hat Fixed 1 release
VersionStatusFixed in
9 Fixed โ€”

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.