From: Tim Kientzle <kientzle@gmail.com>
Date: Sat, 13 Mar 2010 06:40:02 +0000 (-0500)
Subject: Issue 76:  Correct segfault when Zip bidder sees a file that is less than 128k
X-Git-Tag: v3.0.0a~1155
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1fb2ae5cc0d9d5d12bd8bd7ea4a88f138072d6c4;p=thirdparty%2Flibarchive.git

Issue 76:  Correct segfault when Zip bidder sees a file that is less than 128k
and starts with "MZ".  The "MZ" signature identifies executable files that
could be self-extracting Zip files; the Zip bidder incorrectly handled
end-of-file when searching ahead for the Zip contents.

Submitted by:	dardoguidobono

SVN-Revision: 2028
---

diff --git a/libarchive/archive_read_support_format_zip.c b/libarchive/archive_read_support_format_zip.c
index 8f04b5428..49288ac07 100644
--- a/libarchive/archive_read_support_format_zip.c
+++ b/libarchive/archive_read_support_format_zip.c
@@ -225,7 +225,7 @@ archive_read_format_zip_bid(struct archive_read *a)
 			/* Get 4k of data beyond where we stopped. */
 			buff = __archive_read_ahead(a, offset + 4096,
 			    &bytes_avail);
-			if (bytes_avail < offset + 1)
+			if (buff == NULL)
 				break;
 			p = (const char *)buff + offset;
 			while (p + 9 < (const char *)buff + bytes_avail) {