RDMA/core: Fix potential use after free in ib_free_cq()
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.
- Products
- Kernel
- Affected versions
- Not specified
- Fixed versions
- 5.15.221, 6.1.188, 6.12.110, 6.18.52, 6.6.157, 7.2.6
- CVEs
- CVE-2026-92508
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 22:15 UTC · Revision 1
Source evidence
RDMA/core: Fix potential use after free in ib_free_cq()
core-osv · Original sourcePublished 17 Sept 2026, 16:10 UTC
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.
osv:CVE-2026-92508
Kernel
Fixed versions: 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6
Complete source record
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"title": "RDMA/core: Fix potential use after free in ib_free_cq()",
"summary": "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.",
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"modified": "2026-10-28T02:30:31.899001433Z",
"provider": "osv",
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"source_id": "core-osv",
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"published_at": "2026-09-17T16:10:19.443+00:00"
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