CVE-2023-52472

crypto: rsa - add a check for allocation failure

In the Linux kernel, the following vulnerability has been resolved: crypto: rsa - add a check for allocation failure Static checkers insist that the mpi_alloc() allocation can fail so add a check to prevent a NULL dereference. Small allocations like this can't actually fail in current kernels, but adding a check is very simple and makes the static checkers happy.