From 2ea2d686e20d7f29cf0f72f97a5ad3ee808d300a Mon Sep 17 00:00:00 2001
From: mohammad1603 <mohammad.abomokh@arm.com>
Date: Thu, 22 Mar 2018 02:40:43 -0700
Subject: [PATCH] Verify that f_send and f_recv send and receive the expected
length
Verify that f_send and f_recv send and receive the expected length
Conflicts:
ChangeLog
---
ChangeLog | 5 +++--
library/ssl_tls.c | 12 +++++++-----
2 files changed, 10 insertions(+), 7 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 2deaafb34..3ebae33af 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -33,8 +33,9 @@ Changes
* Fix typo in a comment ctr_drbg.c. Contributed by Paul Sokolovsky.
* MD functions deprecated in 2.7.0 are no longer inline, to provide
a migration path for those depending on the library's ABI.
- * Add guard to validate that out_left can not be negative. Raised by
- samoconnor in #1245.
+ * Verify that when (f_send, f_recv and f_recv_timeout) send or receive
+ more than the required length an error is returned. Raised by
+ Sam O'Connor in #1245.
= mbed TLS 2.7.0 branch released 2018-02-03
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index b91577601..b3fb95c50 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -2434,11 +2434,11 @@ int mbedtls_ssl_fetch_input( mbedtls_ssl_context *ssl, size_t nb_want )
if( ret < 0 )
return( ret );
- // At this point ret value is positive, verify that adding ret
- // value to ssl->in_left doesn't cause a wraparound
- if (ssl->in_left + (size_t)ret < ssl->in_left)
+ if ( (size_t)ret > len )
{
- MBEDTLS_SSL_DEBUG_MSG( 1, ( "wraparound happened over in_left value" ) );
+ MBEDTLS_SSL_DEBUG_MSG( 1,
+ ( "f_recv returned %d bytes but only %zu were requested",
+ ret, len ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
@@ -2491,7 +2491,9 @@ int mbedtls_ssl_flush_output( mbedtls_ssl_context *ssl )
if( (size_t)ret > ssl->out_left )
{
- MBEDTLS_SSL_DEBUG_MSG( 1, ( "f_send returned value greater than out left size" ) );
+ MBEDTLS_SSL_DEBUG_MSG( 1,
+ ( "f_send returned %d bytes but only %zu bytes were sent",
+ ret, ssl->out_left ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}