CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's handling of memory regions during NFS/RDMA connections, specifically in the `frwr_wp_create()` function, which can return a negative error code that is currently ignored. This oversight can lead to a dereference of a NULL pointer, resulting in a potential denial of service if a connection attempt is incorrectly marked as successful. Linux system administrators and developers utilizing NFS/RDMA should prioritize this issue to prevent possible disruptions in service.
Original NVD 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.