CVE-2026-31666
Description
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix incorrect return value after changing leaf in lookup_extent_data_ref() After commit 1618aa3c2e01 ("btrfs: simplify return variables in lookup_extent_data_ref()"), the err and ret variables were merged into a single ret variable. However, when btrfs_next_leaf() returns 0 (success), ret is overwritten from -ENOENT to 0. If the first key in the next leaf does not match (different objectid or type), the function returns 0 instead of -ENOENT, making the caller believe the lookup succeeded when it did not. This can lead to operations on the wrong extent tree item, potentially causing extent tree corruption. Fix this by returning -ENOENT directly when the key does not match, instead of relying on the ret variable.
Predictions
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 — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| sles | affected | | |
| debian | bookworm | fixed | 0 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 6.19.13-1 |
| debian | sid | fixed | 6.19.13-1 |
| debian | trixie | fixed | 6.12.85-1 |
| linux-kernel | affected | 6.12.82 | |
| linux-kernel | 6.10 | affected | |
| linux-kernel | 7.0 | affected | |
References
- https://git.kernel.org/stable/c/316fb1b3169efb081d2db910cbbfef445afa03b9
- https://git.kernel.org/stable/c/4125a194db4a6cf91f619f38788272651cb97dce
- https://git.kernel.org/stable/c/450e6a685d0cad95b15f8af152057bd0bf79f50b
- https://git.kernel.org/stable/c/ab1e022379c3c811aa72da8eb0c7507859a1d0f5
- https://www.suse.com/security/cve/CVE-2026-31666.html
- https://security-tracker.debian.org/tracker/CVE-2026-31666
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.