RDMA/core: Fix null-ptr-deref in ibcorecleanup()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.4.224 by commit af8fb5a0600e9ae29950e9422a032c3c22649ee5, it was introduced in version v4.3 by commit 03db3a2d81e6e84f3ed3cb9e087cae17d762642b. For more details please see the references link.