In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Properly handle NULL pointer in dat_cond_set_storage_key() Some callers pass NULL as oldkey. Calling page_cond_set_storage_key() will cause that NULL pointer to get dereferenced. Fix by checking for NULL and assigning the pointer to a dummy local variable to avoid crashes.
https://git.kernel.org/stable/c/88e22ffd1e46b95e40a6afabe486deb1d31a3ae1
https://git.kernel.org/stable/c/75867536746ab2d034488a6a93ee6cde83553342