Merge remote-tracking branch 'upstream-public/pr/1449' into mbedtls-2.7-proposed
diff --git a/ChangeLog b/ChangeLog
index 2bc462f..b7428b1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -21,6 +21,10 @@
overflow. #1179
* Fix memory allocation corner cases in memory_buffer_alloc.c module. Found
by Guido Vranken. #639
+ * Fix a possible arithmetic overflow in ssl_parse_server_key_exchange()
+ that could cause a key exchange to fail on valid data.
+ * Fix a possible arithmetic overflow in ssl_parse_server_psk_hint() that
+ could cause a key exchange to fail on valid data.
Changes
* Clarify the documentation of mbedtls_ssl_setup.
@@ -108,6 +112,8 @@
manner.
* Fix a buffer overread in ssl_parse_server_key_exchange() that could cause
a crash on invalid input.
+ * Fix a buffer overread in ssl_parse_server_psk_hint() that could cause a
+ crash on invalid input.
Features
* Allow comments in test data files.
@@ -242,8 +248,6 @@
* In mbedtls_entropy_free(), properly free the message digest context.
* Fix status handshake status message in programs/ssl/dtls_client.c. Found
and fixed by muddog.
- * Fix a possible arithmetic overflow in ssl_parse_server_key_exchange()
- that could cause a key exchange to fail on valid data.
Changes
* Extend cert_write example program by options to set the certificate version
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 2eec766..eeb2fe2 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -2057,10 +2057,16 @@
*
* opaque psk_identity_hint<0..2^16-1>;
*/
+ if( (*p) > end - 2 )
+ {
+ MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message "
+ "(psk_identity_hint length)" ) );
+ return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
+ }
len = (*p)[0] << 8 | (*p)[1];
*p += 2;
- if( (*p) + len > end )
+ if( (*p) > end - len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message "
"(psk_identity_hint length)" ) );