From: Justus Winter <justus@g10code.com>
Date: Thu, 30 Mar 2017 13:44:35 +0000 (+0200)
Subject: common: Avoid undefined behavior.
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ian/git?a=commitdiff_plain;h=0d2bab1fb95601b821ff0ab79960ec50716c689a;p=gnupg2.git

common: Avoid undefined behavior.

* common/iobuf.c (iobuf_read_line): Do not consider 'length' if
'buffer' is NULL.

Signed-off-by: Justus Winter <justus@g10code.com>
(cherry picked from commit 214fa9012296d796b78f1a3106d656639cf50aef)

Gbp-Pq: Name 0058-common-Avoid-undefined-behavior.patch
---

diff --git a/common/iobuf.c b/common/iobuf.c
index d346027..b8baf7f 100644
--- a/common/iobuf.c
+++ b/common/iobuf.c
@@ -2552,7 +2552,7 @@ iobuf_read_line (iobuf_t a, byte ** addr_of_buffer,
      NUL character in the buffer.  This requires at least 2 bytes.  We
      don't complicate the code by handling the stupid corner case, but
      simply assert that it can't happen.  */
-  assert (length >= 2 || maxlen >= 2);
+  assert (!buffer || length >= 2 || maxlen >= 2);
 
   if (!buffer || length <= 1)
     /* must allocate a new buffer */