guix/gnu/packages/patches/libwmf-CVE-2007-3472.patch

Based on a patch from Fedora.

http://pkgs.fedoraproject.org/cgit/libwmf.git/tree/libwmf-0.2.8.4-CVE-2007-3472.patch

--- libwmf-0.2.8.4/src/extra/gd/gd.c
+++ libwmf-0.2.8.4/src/extra/gd/gd.c
@@ -106,6 +106,18 @@
   gdImagePtr im;
   unsigned long cpa_size;
 
+  if (overflow2(sx, sy)) {
+    return NULL;
+  }
+
+  if (overflow2(sizeof (int *), sy)) {
+    return NULL;
+  }
+
+  if (overflow2(sizeof(int), sx)) {
+    return NULL;
+  }
+
   im = (gdImage *) gdMalloc (sizeof (gdImage));
   if (im == 0) return 0;
   memset (im, 0, sizeof (gdImage));
--- libwmf-0.2.8.4/src/extra/gd/gdhelpers.c	2010-12-06 11:47:31.000000000 +0000
+++ libwmf-0.2.8.4/src/extra/gd/gdhelpers.c	2010-12-06 11:48:04.000000000 +0000
@@ -2,6 +2,7 @@
 #include "gdhelpers.h"
 #include <stdlib.h>
 #include <string.h>
+#include <limits.h>
 
 /* TBB: gd_strtok_r is not portable; provide an implementation */
 
@@ -94,3 +95,18 @@
 {
   free (ptr);
 }
+
+int overflow2(int a, int b)
+{
+	if(a < 0 || b < 0) {
+		fprintf(stderr, "gd warning: one parameter to a memory allocation multiplication is negative, failing operation gracefully\n");
+		return 1;
+	}
+	if(b == 0)
+		return 0;
+	if(a > INT_MAX / b) {
+		fprintf(stderr, "gd warning: product of memory allocation multiplication would exceed INT_MAX, failing operation gracefully\n");
+		return 1;
+	}
+	return 0;
+}
--- libwmf-0.2.8.4/src/extra/gd/gdhelpers.h	2010-12-06 11:47:17.000000000 +0000
+++ libwmf-0.2.8.4/src/extra/gd/gdhelpers.h	2010-12-06 11:48:36.000000000 +0000
@@ -15,4 +15,6 @@
 void *gdMalloc(size_t size);
 void *gdRealloc(void *ptr, size_t size);
 
+int overflow2(int a, int b);
+
 #endif /* GDHELPERS_H */