PCX: Check that filesize is reasonable given header.
--- a/ChangeLog Sat Sep 10 16:48:12 2016 -0500
+++ b/ChangeLog Sat Sep 10 17:01:18 2016 -0500
@@ -1,5 +1,10 @@
2016-09-10 Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
+ * coders/pcx.c (ReadPCXImage): Check that filesize is reasonable
+ given header. Fixes excessive memory allocation followed by
+ eventual file truncation error for corrupt file. Problem was
+ reported via email by Agostino Sarubbo on 2016-09-10.
+
* coders/sgi.c (ReadSGIImage): Check that filesize is reasonable
given header. Fixes excessive memory allocation followed by
eventual file truncation error for corrupt file. Problem was
--- a/coders/pcx.c Sat Sep 10 16:48:12 2016 -0500
+++ b/coders/pcx.c Sat Sep 10 17:01:18 2016 -0500
@@ -1,5 +1,5 @@
/*
-% Copyright (C) 2003 - 2015 GraphicsMagick Group
+% Copyright (C) 2003 - 2016 GraphicsMagick Group
% Copyright (C) 2002 ImageMagick Studio
% Copyright 1991-1999 E. I. du Pont de Nemours and Company
%
@@ -251,6 +251,9 @@
size_t
pcx_packets;
+ magick_off_t
+ file_size;
+
/*
Open image file.
*/
@@ -292,6 +295,7 @@
if (SeekBlob(image,(ExtendedSignedIntegralType) page_table[0],SEEK_SET)
== -1)
ThrowPCXReaderException(CorruptImageError,ImproperImageHeader,image);
+ file_size=GetBlobSize(image);
count=ReadBlob(image,1,(char *) &pcx_info.identifier);
for (id=1; id < 1024; id++)
{
@@ -455,6 +459,34 @@
if (CheckImagePixelLimits(image, exception) != MagickPass)
ThrowReaderException(ResourceLimitError,ImagePixelLimitExceeded,image);
+
+ /*
+ Check that filesize is reasonable given header
+ */
+ {
+ double
+ uncompressed_size;
+
+ uncompressed_size=((double) image->rows*pcx_info.bytes_per_line*pcx_info.planes);
+ (void) LogMagickEvent(CoderEvent,GetMagickModule(),
+ "Uncompressed size: %.0f", uncompressed_size);
+ if (pcx_info.encoding == 0)
+ {
+ /* Not compressed */
+ if (uncompressed_size > file_size)
+ ThrowReaderException(CorruptImageError,InsufficientImageDataInFile,
+ image);
+ }
+ else
+ {
+ /* RLE compressed */
+ if (uncompressed_size > file_size*254.0)
+ ThrowReaderException(CorruptImageError,InsufficientImageDataInFile,
+ image);
+ }
+ }
+
+
/*
Read image data.
*/
--- a/www/Changelog.html Sat Sep 10 16:48:12 2016 -0500
+++ b/www/Changelog.html Sat Sep 10 17:01:18 2016 -0500
@@ -38,6 +38,10 @@
<p>2016-09-10 Bob Friesenhahn <<a class="reference external" href="mailto:bfriesen%40simple.dallas.tx.us">bfriesen<span>@</span>simple<span>.</span>dallas<span>.</span>tx<span>.</span>us</a>></p>
<blockquote>
<ul class="simple">
+<li>coders/pcx.c (ReadPCXImage): Check that filesize is reasonable
+given header. Fixes excessive memory allocation followed by
+eventual file truncation error for corrupt file. Problem was
+reported via email by Agostino Sarubbo on 2016-09-10.</li>
<li>coders/sgi.c (ReadSGIImage): Check that filesize is reasonable
given header. Fixes excessive memory allocation followed by
eventual file truncation error for corrupt file. Problem was