- MFB: #37346, invalid colormap format

ext/gd/libgd/gd_gif_in.c

@@ -44,7 +44,7 @@ static int set_verbose(void)
 #define LOCALCOLORMAP  0x80
 #define BitSet(byte, bit)      (((byte) & (bit)) == (bit))
 
-#define        ReadOK(file,buffer,len) (gdGetBuf(buffer, len, file) != 0)
+#define        ReadOK(file,buffer,len) (gdGetBuf(buffer, len, file) > 0)
 
 #define LM_to_uint(a,b)                        (((b)<<8)|(a))
 
@@ -184,14 +184,19 @@ gdImageCreateFromGifCtx(gdIOCtxPtr fd)
 
                imw = LM_to_uint(buf[4],buf[5]);
                imh = LM_to_uint(buf[6],buf[7]);
-	       if (!(im = gdImageCreate(imw, imh))) {
-			 return 0;
-	       }
-               im->interlace = BitSet(buf[8], INTERLACE);
+
+			   if (!useGlobalColormap) {
+				   if (ReadColorMap(fd, bitPixel, localColorMap)) {
+					   return 0;
+				   }
+			   }
+
+			   if (!(im = gdImageCreate(imw, imh))) {
+				   return 0;
+			   }
+
+			   im->interlace = BitSet(buf[8], INTERLACE);
                if (! useGlobalColormap) {
-                       if (ReadColorMap(fd, bitPixel, localColorMap)) {
-                                 return 0;
-                       }
                        ReadImage(im, fd, imw, imh, localColorMap,
                                  BitSet(buf[8], INTERLACE));
                                  /*1.4//imageCount != imageNumber); */

ext/gd/tests/bug37346.phpt

@@ -0,0 +1,13 @@
+--TEST--
+Bug #37346 (gdimagecreatefromgif, bad colormap)
+--SKIPIF--
+<?php 
+	if (!extension_loaded('gd')) die("skip gd extension not available\n"); 
+	if (!GD_BUNDLED) die('skip external GD libraries always fail');
+?>
+--FILE--
+<?php
+$im = imagecreatefromgif(dirname(__FILE__) . '/bug37346.gif');
+?>
+--EXPECTF--
+Warning: imagecreatefromgif(): '%sbug37346.gif' is not a valid GIF file in %sbug37346.php on line %d