Merge remote-tracking branch 'upstream-public/pr/1440' into development-proposed
diff --git a/ChangeLog b/ChangeLog
index 0d079c8..b9af47b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -21,6 +21,8 @@
against Bellcore glitch attack.
* 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
@@ -59,6 +61,8 @@
parsing the subject alternative names.
* 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
* Fix tag lengths and value ranges in the documentation of CCM encryption.
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index fc90f86..88864b8 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -2058,10 +2058,16 @@
*
* 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)" ) );