CVE-2026-31577
Description
In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix NULL i_assoc_inode dereference in nilfs_mdt_save_to_shadow_map The DAT inode's btree node cache (i_assoc_inode) is initialized lazily during btree operations. However, nilfs_mdt_save_to_shadow_map() assumes i_assoc_inode is already initialized when copying dirty pages to the shadow map during GC. If NILFS_IOCTL_CLEAN_SEGMENTS is called immediately after mount before any btree operation has occurred on the DAT inode, i_assoc_inode is NULL leading to a general protection fault. Fix this by calling nilfs_attach_btree_node_cache() on the DAT inode in nilfs_dat_read() at mount time, ensuring i_assoc_inode is always initialized before any GC operation can use it.
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 | affected | |
| debian | bullseye | affected | |
| debian | forky | fixed | 6.19.14-1 |
| debian | sid | fixed | 6.19.14-1 |
| debian | trixie | fixed | 6.12.85-1 |
| linux-kernel | affected | 6.6.136 |
References
- https://git.kernel.org/stable/c/41de342278ae025c99cc8d33648773f05e306cf1
- https://git.kernel.org/stable/c/449ec5fc99f45974525ba9eea16b6670c45cd363
- https://git.kernel.org/stable/c/4a4e0328edd9e9755843787d28f16dd4165f8b48
- https://git.kernel.org/stable/c/7318e3549518ce8f14776a489d86488d80d7e2c8
- https://git.kernel.org/stable/c/97fb7afec404912d967a7d4715f37742666b3084
- https://git.kernel.org/stable/c/c36e206f302f1ddefed92d09ecbba070e1ae079e
- https://www.suse.com/security/cve/CVE-2026-31577.html
- https://security-tracker.debian.org/tracker/CVE-2026-31577
CWEs
CWE-476
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.