Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: mm: zswap: fix shrinker NULL crash with cgroup_disable=memory Christian reports a NULL deref in zswap that he bisected down to the zswap shrinker. The issue also cropped up in the bug trackers of libguestfs [1] and the Red Hat bugzilla [2]. The problem is that when memcg is disabled with the boot time flag, the zswap shrinker might get called with sc->memcg == NULL. This is okay in many places, like the lruvec operations. But it crashes in memcg_page_state() - which is only used due to the non-node accounting of cgroup's the zswap memory to begin with. Nhat spotted that the memcg can be NULL in the memcg-disabled case, and I was then able to reproduce the crash locally as well. [1] https://github.com/libguestfs/libguestfs/issues/139 [2] https://bugzilla.redhat.com/show_bug.cgi?id=2275252
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected b5ba474f3f518701249598b35c581b92a3c95b48 before b0fdabc908a7f81d12382c87ca9e46a9c2e14042; affected b5ba474f3f518701249598b35c581b92a3c95b48 before 682886ec69d22363819a83ddddd5d66cb5c791e1 |
| Linux / Linux | affected 6.8; unaffected 0 before 6.8; unaffected 6.8.9 through 6.8.*; unaffected 6.9 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/b0fdabc908a7f81d12382c87ca9e46a9c2e14042
- https://git.kernel.org/stable/c/682886ec69d22363819a83ddddd5d66cb5c791e1
ADP enrichment
No English description supplied.
No references supplied.
No English description supplied.