In the Linux kernel, the following vulnerability has been resolved: RDMA/mad: Fix receive buffer leak when PKey enforcement fails ib_mad_complete_recv() initializes mad_recv_wc->rmpp_list and then runs ib_mad_enforce_security() before linking recv_buf onto that list. On failure it calls ib_free_recv_mad(), which only walks rmpp_list and frees the ib_mad_private of every buffer found there. As the list is still empty at that point, nothing is freed at all. The caller cannot clean up either: ib_mad_recv_done() sets recv to NULL right after ib_mad_complete_recv() returns, assuming the MAD layer took ownership of the buffer. Every MAD that fails the PKey check therefore leaks one ib_mad_private (about 300 bytes per IB port MAD, ~2K for OPA), and a remote node can trigger this repeatedly by sending MADs with a wrong PKey. Link recv_buf onto rmpp_list right after the list is initialized, so the error path has something to free.
Fix
Microsoft's update · Moderate
- Release Notes — azl3 kernel 6.6.157.1-1 on Azure Linux 3.0 · build 6.6.158.1-1
From the 2026-Oct release note of Microsoft's Security Update Guide, revised 2026-10-29.
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 2
- StatusReceived → PublishedNVD modified 2026-10-19 09:18
- First seenunscoredNVD modified 2026-10-19 10:18
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 8
- https://git.kernel.org/stable/c/3476c28c9addfa253f505e6bd87f1f5598b961d0
- https://git.kernel.org/stable/c/39c4ea72a40503e102ae07e6776005f96ca078a6
- https://git.kernel.org/stable/c/4617c9a856188674dddb0ca66979746d07688579
- https://git.kernel.org/stable/c/5091e25ec503f7fc02723ca435226467b68caac7
- https://git.kernel.org/stable/c/752b30e9d339008e5ce7eed412e9446078916129
- https://git.kernel.org/stable/c/8e2036fb47a5b152d53eadbd35abf311bd34cc7f
- https://git.kernel.org/stable/c/bad289e42f512646a988f278f536d21547df73f1
- https://git.kernel.org/stable/c/c0d8df85db146d6275e226cb950023be69dd6c77