In the Linux kernel, the following vulnerability has been resolved: svcrdma: Clear sc_cm_id when ADDR_CHANGE replacement fails When svc_rd

In the Linux kernel, the following vulnerability has been resolved:

svcrdma: Clear sc_cm_id when ADDR_CHANGE replacement fails

When svc_rdma_listen_handler() handles RDMA_CM_EVENT_ADDR_CHANGE,
it creates a replacement listener cm_id and returns 1, telling
the CM core to destroy the old one. If the replacement allocation
fails, sc_cm_id still points at the old cm_id that the CM core is
about to destroy. Any subsequent dereference of sc_cm_id --
such as svc_rdma_detach()'s rdma_disconnect() call -- is a
use-after-free.

NULL sc_cm_id on the failure path and guard svc_rdma_detach()'s
rdma_disconnect() call against NULL so that the listener can
be torn down safely when the server shuts down.