Code:  tbGetBuffer(unsigned size)
 {
    char *rtrn;
 
    if (size >= BUFFER_SIZE)
        return NULL;
    if ((BUFFER_SIZE - tbNext) <= size)
        tbNext = 0;
    rtrn = &textBuffer[tbNext];
    tbNext += size;
    return rtrn;
 }

Vulnerability Type: Overflow
CWE ID: CWE-119
Summary: In X.Org Server (aka xserver and xorg-server) before 1.19.4, a local attacker authenticated to the X server could overflow a global buffer, causing crashes of the X server or potentially other problems by injecting large or malformed XKB related atoms and accessing them via xkbcomp.
Commit Message: 