Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Prevent rereg_mr for non-mem regions When a QP/CQ/SRQ is created, a two step process is used where the buffer is allocated in userspace and explicitly registered with the normal reg_mr mechanism prior to creating the actual QP/CQ/SRQ object. These special registrations are indicated via an ABI field so the driver knows that they do not have a valid mkey and to skip the actual CQP command submission. Since these are real MR objects from the core's perspective, it is possible for a user application to invoke rereg_mr on them and cause a real CQP op to be emitted with the zero-initialized mkey value of 0. Fix this by preventing rereg_mr on these special regions.
References5
- git.kernel.org/stable/c/a846aecb931b4d65d5eafa92a0623545af46d4f2
- git.kernel.org/stable/c/b5029e91c63406e4f4c8d58161048b41b6f0bd8c
- git.kernel.org/stable/c/ca1c29f05274b737dc964e28b97803750d7cf7ec
- git.kernel.org/stable/c/dbaa37e060918c45517786e37ecab0f300b48fa9
- git.kernel.org/stable/c/fb46d134e1b8690bed2da9005b36d32d2efd34ac
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: 3 · as of 12 November 2026
- CWE
- CWE-20
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