Code: ExprAppendMultiKeysymList(ExprDef *expr, ExprDef *append)
{
    unsigned nSyms = darray_size(expr->keysym_list.syms);
    unsigned numEntries = darray_size(append->keysym_list.syms);

    darray_append(expr->keysym_list.symsMapIndex, nSyms);
     darray_append(expr->keysym_list.symsNumEntries, numEntries);
     darray_concat(expr->keysym_list.syms, append->keysym_list.syms);
 
    FreeStmt((ParseCommon *) &append);
 
     return expr;
 }

Vulnerability Type: 
CWE ID: CWE-416
Summary: An invalid free in ExprAppendMultiKeysymList in xkbcomp/ast-build.c in xkbcommon before 0.8.1 could be used by local attackers to crash xkbcommon keymap parsers or possibly have unspecified other impact by supplying a crafted keymap file.
Commit Message: xkbcomp: fix pointer value for FreeStmt

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>