Re:[oss-security] Re: a bug in gif2rgb.c in giflib-5.1.2

[xiaoqixue_1 <xiaoqixue_1 () 163 com>]

It has been fixed now.

GifFile->SHeight and GifFile->SWidth both could result to zero memory allocation actually.
the patch as follows:
http://sourceforge.net/p/giflib/code/ci/4cc68b315ff9a378aef6664e1be6b2144ad4a5e6/#diff-2

--- a/util/gif2rgb.c+++ b/util/gif2rgb.c@@ -378,8 +378,8 @@
        }
     }
 
-    if (GifFile->SHeight == 0) {-      fprintf(stderr, "Image of height 0\n");+    if (GifFile->SHeight == 0 || 
GifFile->SWidth == 0) {+       fprintf(stderr, "Image of width or height 0\n");
        exit(EXIT_FAILURE);
     }







At 2016-01-27 13:40:08, cve-assign () mitre org wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA256
>
> > We find a memory allocation whose size could be zero in gif2rgb.c.
> > and It will result to several memory out of bound read and write. the bug in gif2rgb.c:386 :
> >
> > 386 if ((ScreenBuffer = (GifRowType *) 
> > 387 malloc(GifFile->SHeight * sizeof(GifRowType))) == NULL) 
> > 388 GIF_EXIT("Failed to allocate memory required, aborted.");
> >
> >
> > Please see "http://sourceforge.net/p/giflib/bugs/82/"; for more details.
>
> Can you provide more information about the relationship between
> http://sourceforge.net/p/giflib/bugs/82/ and the above instance of
> GifFile->SHeight in the malloc call? The
> http://sourceforge.net/p/giflib/code/ci/4cc68b315ff9a378aef6664e1be6b2144ad4a5e6/
> patch for http://sourceforge.net/p/giflib/bugs/82/ adds a check for
> "GifFile->SWidth == 0" but does not add new validation of the
> GifFile->SHeight value.
>
> - -- 
> CVE assignment team, MITRE CVE Numbering Authority
> M/S M300
> 202 Burlington Road, Bedford, MA 01730 USA
> [ PGP key available through http://cve.mitre.org/cve/request_id.html ]
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