File cups-2.2.7-CVE-2023-4504.patch of Package cups.34073

--- filter/interpret.c.orig	2018-03-23 04:48:36.000000000 +0100
+++ filter/interpret.c	2023-09-12 12:31:15.258214485 +0200
@@ -1117,6 +1117,18 @@ scan_ps(_cups_ps_stack_t *st,		/* I  - S
 
 	    cur ++;
 
+	   /*
+	    * Return NULL if we reached NULL terminator, a lone backslash
+	    * is not a valid character in PostScript.
+	    */
+
+	    if (!*cur)
+	    {
+	      *ptr = NULL;
+
+	      return (NULL);
+	    }
+
             if (*cur == 'b')
 	      *valptr++ = '\b';
 	    else if (*cur == 'f')