From 161ff6c5fa872ba77be22d2093920cf505534508 Mon Sep 17 00:00:00 2001
From: Philippe Antoine
Date: Fri, 23 Mar 2018 20:51:38 +0100
Subject: [PATCH] Adds multiple checks to avoid buffer over reads
Reviewed-by: Rich Salz
Reviewed-by: Andy Polyakov
Reviewed-by: Bernd Edlinger
(Merged from https://github.com/openssl/openssl/pull/5675)
---
ssl/t1_trce.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/ssl/t1_trce.c b/ssl/t1_trce.c
index f8d0501aa5..f888d24673 100644
--- a/ssl/t1_trce.c
+++ b/ssl/t1_trce.c
@@ -888,6 +888,8 @@ static int ssl_print_extensions(BIO *bio, int indent, int server,
BIO_puts(bio, "No Extensions\n");
return 1;
}
+ if (msglen < 2)
+ return 0;
extslen = (msg[0] << 8) | msg[1];
if (extslen != msglen - 2)
return 0;
@@ -1293,6 +1295,8 @@ static int ssl_print_cert_request(BIO *bio, int indent, const SSL *ssl,
msg += xlen;
}
+ if (msglen < 2)
+ return 0;
xlen = (msg[0] << 8) | msg[1];
BIO_indent(bio, indent, 80);
if (msglen < xlen + 2)
@@ -1493,7 +1497,15 @@ void SSL_trace(int write_p, int version, int content_type,
switch (content_type) {
case SSL3_RT_HEADER:
{
- int hvers = msg[1] << 8 | msg[2];
+ int hvers;
+
+ /* avoid overlapping with length at the end of buffer */
+ if (msglen < (SSL_IS_DTLS(ssl) ? 13 : 5)) {
+ BIO_puts(bio, write_p ? "Sent" : "Received");
+ ssl_print_hex(bio, 0, " too short message", msg, msglen);
+ break;
+ }
+ hvers = msg[1] << 8 | msg[2];
BIO_puts(bio, write_p ? "Sent" : "Received");
BIO_printf(bio, " Record\nHeader:\n Version = %s (0x%x)\n",
ssl_trace_str(hvers, ssl_version_tbl), hvers);
--
2.25.1