xkbcommon null pointer dereference vulnerability (CNVD-2019-02666)

xkbcommon is a keyboard key mapping compiler and support library. A null pointer dereference vulnerability exists in the 'CopyKeyAliasesToKeymap' function of the xkbcomp/keycodes.c file in versions of xkbcommon prior to xkbcommon 0.8.1, which stems from a failure of the program to check for the u...