Bullet-proof against integer overflow.

Sat Mar  2 21:28:03 2002  Owen Taylor  <otaylor@redhat.com>

        * gdk-pixbuf.c (gdk_pixbuf_new): Bullet-proof against integer
        overflow.

diff --git a/gdk-pixbuf/ChangeLog b/gdk-pixbuf/ChangeLog
index 84cf31878017f0d9fa6e1ed1fd4dad6d161d6a8d..3f11592e860a423d053419e2f0bf4584ecc99f70 100644 (file)
--- a/gdk-pixbuf/ChangeLog
+++ b/gdk-pixbuf/ChangeLog
@@ -1,3 +1,8 @@
+Sat Mar  2 21:28:03 2002  Owen Taylor  <otaylor@redhat.com>
+
+       * gdk-pixbuf.c (gdk_pixbuf_new): Bullet-proof against integer
+       overflow.
+
 2002-03-03  Tor Lillqvist  <tml@iki.fi>
 
        * gtk-pixbuf.rc.in: Remove.
@@ -18,7 +23,7 @@ Wed Feb 27 18:33:04 2002  Owen Taylor  <otaylor@redhat.com>
 
        * gdk-pixdata.c (gdk_pixdata_to_csource): Use {} not
        () to group around string assigned to char[]. (#72767,
-       Tomas Ögren)
+       Tomas Ã\83Â\96gren)
 
 2002-02-21  Havoc Pennington  <hp@pobox.com>
 
@@ -1240,7 +1245,7 @@ Wed Jun 21 16:02:48 2000  Owen Taylor  <otaylor@redhat.com>
 2000-06-05     Mathieu Lacage  <mathieu@gnome.org>
 
        * configure.in: add some gtk parameters to the
-       GDK_PIXBUF_LIB²S and GDK_PIXBUG_INCLUDEDIR vars. One more
+       GDK_PIXBUF_LIB²S and GDK_PIXBUG_INCLUDEDIR vars. One more
        fight in my crusade for strange prefix compile...
 
 2000-05-30  Not Zed  <NotZed@HelixCode.com>
@@ -1337,7 +1342,7 @@ Fri May  5 12:16:32 2000  Owen Taylor  <otaylor@redhat.com>
        * gdk-pixbuf/Makefile.am (INCLUDES): Add $(GNOME_CFLAGS).
        Reported by Jens Finke.
 
-2000-04-14 Tomasz K³opczko <kloczek@pld.org.pl>
+2000-04-14 Tomasz K³opczko <kloczek@pld.org.pl>
 
        * gdk-pixbuf/pixops/makefile.am: $(LIBART_CFLAGS) replaced by 
        $(GTK_CFLAGS) - now gdk-pixbuf compiles correctly.

diff --git a/gdk-pixbuf/gdk-pixbuf.c b/gdk-pixbuf/gdk-pixbuf.c
index 93c4c6db2c982d109df5b7cfb3c66f4f6f1846dc..995fe4d91511da93d9a551d8ff74d4554a803c45 100644 (file)
--- a/gdk-pixbuf/gdk-pixbuf.c
+++ b/gdk-pixbuf/gdk-pixbuf.c
@@ -144,18 +144,29 @@ gdk_pixbuf_new (GdkColorspace colorspace, gboolean has_alpha, int bits_per_sampl
        guchar *buf;
        int channels;
        int rowstride;
+        gsize bytes;
 
        g_return_val_if_fail (colorspace == GDK_COLORSPACE_RGB, NULL);
        g_return_val_if_fail (bits_per_sample == 8, NULL);
        g_return_val_if_fail (width > 0, NULL);
        g_return_val_if_fail (height > 0, NULL);
 
-       /* Always align rows to 32-bit boundaries */
+        if (width <= 0 || height <= 0)
+                return NULL;
 
        channels = has_alpha ? 4 : 3;
-       rowstride = 4 * ((channels * width + 3) / 4);
+        rowstride = width * channels;
+        if (rowstride / channels != width || rowstride + 3 < 0) /* overflow */
+                return NULL;
+        
+       /* Always align rows to 32-bit boundaries */
+       rowstride = (rowstride + 3) & ~3;
 
-       buf = g_try_malloc (height * rowstride);
+        bytes = height * rowstride;
+        if (bytes / rowstride !=  height) /* overflow */
+                return NULL;
+            
+       buf = g_try_malloc (bytes);
        if (!buf)
                return NULL;