From: Tim Kientzle <kientzle@acm.org>
Date: Sat, 23 Mar 2013 06:48:41 +0000 (-0700)
Subject: Limit write requests to at most INT_MAX.
X-Git-Tag: v3.1.900a~351^2~13
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=22531545514043e04633e1c015c7540b9de9dbe4;p=thirdparty%2Flibarchive.git

Limit write requests to at most INT_MAX.
This prevents a certain common programming error (passing -1 to write)
from leading to other problems deeper in the library.
---

diff --git a/libarchive/archive_write.c b/libarchive/archive_write.c
index eede5e057..be8562150 100644
--- a/libarchive/archive_write.c
+++ b/libarchive/archive_write.c
@@ -673,8 +673,13 @@ static ssize_t
 _archive_write_data(struct archive *_a, const void *buff, size_t s)
 {
 	struct archive_write *a = (struct archive_write *)_a;
+	const size_t max_write = INT_MAX;
+
 	archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 	    ARCHIVE_STATE_DATA, "archive_write_data");
+	/* In particular, this catches attempts to pass negative values. */
+	if (s > max_write)
+		s = max_write;
 	archive_clear_error(&a->archive);
 	return ((a->format_write_data)(a, buff, s));
 }