CVE-2026-63886 scsi: target: iscsi: Validate CHAP_R length before base64 decode

In the Linux kernel, the following vulnerability has been resolved: scsi: target: iscsi: Validate CHAPR length before base64 decode chapservercomputehash allocates clientdigest as kzallocchap-digestsize and then, for BASE64-encoded responses, passes chapr directly to chapbase64decode without...