Merge remote-tracking branch 'upstream-public/pr/1450' into mbedtls-2.1-proposed
diff --git a/ChangeLog b/ChangeLog
index deeaccd..ae31305 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -19,6 +19,8 @@
resumption of the session).
* 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
* Extend PKCS#8 interface by introducing support for the entire SHA
@@ -55,6 +57,8 @@
* In mbedtls_entropy_free(), properly free the message digest context.
* 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
* Clarified the documentation of mbedtls_ssl_setup.
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index b607fda..c0c424b 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -1850,10 +1850,16 @@
*
* 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)" ) );