Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: out-of-bounds read/write in glx changedrawableattributes

An out-of-bounds read flaw was found in the X.Org X server and Xwayland in __glXDisp_ChangeDrawableAttributes(). A wrong size validation check can read a client-controlled number of bytes, exceeding the request buffer, leading to information disclosure. A write path also exists but requires byte-swapped clients which is disabled by default.