Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Fix potential use after free in ib_free_cq() When accessing a CQ via the netlink path the only synchronization mechanism for the said CQ is rdma_restrack_get(). Currently, rdma_restrack_del() is invoked at the end of ib_free_cq(), which is too late, since by that point vendor-specific resources associated with the CQ might already be freed. This can leave a short window where the CQ remains accessible through restrack, leading to a potential use-after-free. Fix this by moving the rdma_restrack_del() call to be before the freeing of the vendor-specific resources ensuring that the CQ is removed from restrack before its internal resources are released. This guarantees that no new users hold references to a CQ that is in the process of destruction.
References7
- git.kernel.org/stable/c/29dc2f8e1c97372c2871a70088707933515fbd5b
- git.kernel.org/stable/c/43403fe45379c64fa6276e5a8ede44493e5d2d3d
- git.kernel.org/stable/c/76f2cb4f721815c3b6262a6dc2151de88646924c
- git.kernel.org/stable/c/91f8a17a22ab615a03743120e19935e731f28fb9
- git.kernel.org/stable/c/9abea37942534eeb049335476178696b654b000c
- git.kernel.org/stable/c/a804b162f9bc2b38b2ed1b4752eea9faadb1645b
- git.kernel.org/stable/c/b8dcca427096fc9c50f1b376847fea72bc842d31
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 8 November 2026
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