CVE-2026-52956 libceph: Fix potential out-of-bounds access in __ceph_x_decrypt()

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in cephxdecrypt In cephxdecrypt, a part of the buffer p is interpreted as a cephxencryptheader, and the magic field of this struct is accessed. This happens without any guarantee that t...