Commit e99ab8ff authored by David Benjamin's avatar David Benjamin Committed by Rich Salz
Browse files

Fix DH error-handling in tls_process_key_exchange. 



The set0 setters take ownership of their arguments, so the values should
be set to NULL to avoid a double-free in the cleanup block should
ssl_security(SSL_SECOP_TMP_DH) fail. Found by BoringSSL's WeakDH test.

Reviewed-by: default avatarKurt Roeckx <kurt@openssl.org>
Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1299)
parent 3307000d

ssl/statem/statem_clnt.c

+2 −0
Original line number Diff line number Diff line
@@ -1461,12 +1461,14 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt) 
            SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_BN_LIB);

            goto dherr;

        }

        p = g = NULL;



        if (!DH_set0_key(dh, bnpub_key, NULL)) {

            al = SSL_AD_INTERNAL_ERROR;

            SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_BN_LIB);

            goto dherr;

        }

        bnpub_key = NULL;



        if (!ssl_security(s, SSL_SECOP_TMP_DH, DH_security_bits(dh), 0, dh)) {

            al = SSL_AD_HANDSHAKE_FAILURE;