CVE-2026-72467xprtrdma: Check frwr_wp_create() during connect

Official description

In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Check frwr_wp_create() during connect frwr_wp_create() creates the singleton Memory Region used to encode padding for Write chunks whose payload length is not XDR-aligned. Its failure paths return a negative errno and leave ep->re_write_pad_mr set to NULL. rpcrdma_xprt_connect() currently ignores that return value. If frwr_wp_create() fails after the rest of the connection setup succeeds, xprt_rdma_connect_worker() treats the connection attempt as successful and sets XPRT_CONNECTED. A later NFS/RDMA read with a non-4-byte-aligned receive page length reaches rpcrdma_encode_write_list(), passes the NULL write-pad MR to encode_rdma_segment(), and dereferences it. This is locally triggerable on an NFS/RDMA client after a connect or reconnect hits a local MR allocation, DMA-map, MR-map, or post-send failure; a remote peer alone cannot force the local MR setup failure. Check the return value and fail the connect as -ENOTCONN, matching the adjacent setup failures. This keeps XPRT_CONNECTED clear and lets the normal reconnect path retry.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/3b252fe1778b2cdd68283146455929801bc2abd7
• https://git.kernel.org/stable/c/dd798b76a3481e392820c3ae86ed4592858c6b0f
• https://git.kernel.org/stable/c/6b7be4f3feae322f1c2c40a3bdc99db93574a49e
• https://git.kernel.org/stable/c/7471e66373a4444a57ef2192f8c4081202c54f45
• https://git.kernel.org/stable/c/ef3b79edf14b6bfb0d21a26ccb0463f9cf82c6a9
• https://git.kernel.org/stable/c/0f13fc7c7d2e0427517e63c739277a4cd338b0c5