File curl-CVE-2019-3823.patch of Package curl.25399
From 89dd3f49e1248d7f39401ecc9eecb4e82885e629 Mon Sep 17 00:00:00 2001
From: Daniel Gustafsson <daniel@yesql.se>
Date: Sat, 19 Jan 2019 00:42:47 +0100
Subject: [PATCH 3/3] smtp: avoid risk of buffer overflow in strtol
If the incoming len 5, but the buffer does not have a termination
after 5 bytes, the strtol() call may keep reading through the line
buffer until is exceeds its boundary. Fix by ensuring that we are
using a bounded read with a temporary buffer on the stack.
Reported-by: Brian Carpenter (Geeknik Labs)
---
lib/smtp.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/lib/smtp.c b/lib/smtp.c
index 84fc68e41..d55647b12 100644
--- a/lib/smtp.c
+++ b/lib/smtp.c
@@ -3,11 +3,11 @@
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
*
@@ -205,12 +205,16 @@ static bool smtp_endofresp(struct connectdata *conn, char *line, size_t len,
/* Do we have a command response? This should be the response code followed
by a space and optionally some text as per RFC-5321 and as outlined in
Section 4. Examples of RFC-4954 but some e-mail servers ignore this and
only send the response code instead as per Section 4.2. */
if(line[3] == ' ' || len == 5) {
+ char tmpline[6];
+
result = TRUE;
- *resp = curlx_sltosi(strtol(line, NULL, 10));
+ memset(tmpline, '\0', sizeof(tmpline));
+ memcpy(tmpline, line, (len == 5 ? 5 : 3));
+ *resp = curlx_sltosi(strtol(tmpline, NULL, 10));
/* Make sure real server never sends internal value */
if(*resp == 1)
*resp = 0;
}
--
2.20.1