| From 68c69f516f95df1faa42e5647e9ce7cfdc41ac38 Mon Sep 17 00:00:00 2001 |
| From: Nanang Izzuddin <nanang@teluu.com> |
| Date: Wed, 16 Jun 2021 12:15:29 +0700 |
| Subject: [PATCH 2/2] - Fix silly mistake: accepted active socket created |
| without group lock in SSL socket. - Replace assertion with normal validation |
| check of SSL socket instance in OpenSSL verification callback (verify_cb()) |
| to avoid crash, e.g: if somehow race condition with SSL socket destroy |
| happens or OpenSSL application data index somehow gets corrupted. |
| |
| --- |
| pjlib/src/pj/ssl_sock_imp_common.c | 3 +- |
| pjlib/src/pj/ssl_sock_ossl.c | 45 +++++++++++++++++++++++++----- |
| 2 files changed, 40 insertions(+), 8 deletions(-) |
| |
| --- a/pjlib/src/pj/ssl_sock_imp_common.c |
| +++ b/pjlib/src/pj/ssl_sock_imp_common.c |
| @@ -949,6 +949,7 @@ static pj_bool_t asock_on_accept_complet |
| |
| /* Create active socket */ |
| pj_activesock_cfg_default(&asock_cfg); |
| + asock_cfg.grp_lock = ssock->param.grp_lock; |
| asock_cfg.async_cnt = ssock->param.async_cnt; |
| asock_cfg.concurrency = ssock->param.concurrency; |
| asock_cfg.whole_data = PJ_TRUE; |
| @@ -964,7 +965,7 @@ static pj_bool_t asock_on_accept_complet |
| goto on_return; |
| |
| pj_grp_lock_add_ref(glock); |
| - asock_cfg.grp_lock = ssock->param.grp_lock = glock; |
| + ssock->param.grp_lock = glock; |
| pj_grp_lock_add_handler(ssock->param.grp_lock, ssock->pool, ssock, |
| ssl_on_destroy); |
| } |
| --- a/pjlib/src/pj/ssl_sock_ossl.c |
| +++ b/pjlib/src/pj/ssl_sock_ossl.c |
| @@ -327,7 +327,8 @@ static pj_status_t STATUS_FROM_SSL_ERR(c |
| ERROR_LOG("STATUS_FROM_SSL_ERR", err, ssock); |
| } |
| |
| - ssock->last_err = err; |
| + if (ssock) |
| + ssock->last_err = err; |
| return GET_STATUS_FROM_SSL_ERR(err); |
| } |
| |
| @@ -344,7 +345,8 @@ static pj_status_t STATUS_FROM_SSL_ERR2( |
| /* Dig for more from OpenSSL error queue */ |
| SSLLogErrors(action, ret, err, len, ssock); |
| |
| - ssock->last_err = ssl_err; |
| + if (ssock) |
| + ssock->last_err = ssl_err; |
| return GET_STATUS_FROM_SSL_ERR(ssl_err); |
| } |
| |
| @@ -587,6 +589,13 @@ static pj_status_t init_openssl(void) |
| |
| /* Create OpenSSL application data index for SSL socket */ |
| sslsock_idx = SSL_get_ex_new_index(0, "SSL socket", NULL, NULL, NULL); |
| + if (sslsock_idx == -1) { |
| + status = STATUS_FROM_SSL_ERR2("Init", NULL, -1, ERR_get_error(), 0); |
| + PJ_LOG(1,(THIS_FILE, |
| + "Fatal error: failed to get application data index for " |
| + "SSL socket")); |
| + return status; |
| + } |
| |
| return status; |
| } |
| @@ -614,21 +623,36 @@ static int password_cb(char *buf, int nu |
| } |
| |
| |
| -/* SSL password callback. */ |
| +/* SSL certificate verification result callback. |
| + * Note that this callback seems to be always called from library worker |
| + * thread, e.g: active socket on_read_complete callback, which should have |
| + * already been equipped with race condition avoidance mechanism (should not |
| + * be destroyed while callback is being invoked). |
| + */ |
| static int verify_cb(int preverify_ok, X509_STORE_CTX *x509_ctx) |
| { |
| - pj_ssl_sock_t *ssock; |
| - SSL *ossl_ssl; |
| + pj_ssl_sock_t *ssock = NULL; |
| + SSL *ossl_ssl = NULL; |
| int err; |
| |
| /* Get SSL instance */ |
| ossl_ssl = X509_STORE_CTX_get_ex_data(x509_ctx, |
| SSL_get_ex_data_X509_STORE_CTX_idx()); |
| - pj_assert(ossl_ssl); |
| + if (!ossl_ssl) { |
| + PJ_LOG(1,(THIS_FILE, |
| + "SSL verification callback failed to get SSL instance")); |
| + goto on_return; |
| + } |
| |
| /* Get SSL socket instance */ |
| ssock = SSL_get_ex_data(ossl_ssl, sslsock_idx); |
| - pj_assert(ssock); |
| + if (!ssock) { |
| + /* SSL socket may have been destroyed */ |
| + PJ_LOG(1,(THIS_FILE, |
| + "SSL verification callback failed to get SSL socket " |
| + "instance (sslsock_idx=%d).", sslsock_idx)); |
| + goto on_return; |
| + } |
| |
| /* Store verification status */ |
| err = X509_STORE_CTX_get_error(x509_ctx); |
| @@ -706,6 +730,7 @@ static int verify_cb(int preverify_ok, X |
| if (PJ_FALSE == ssock->param.verify_peer) |
| preverify_ok = 1; |
| |
| +on_return: |
| return preverify_ok; |
| } |
| |
| @@ -1213,6 +1238,12 @@ static void ssl_destroy(pj_ssl_sock_t *s |
| static void ssl_reset_sock_state(pj_ssl_sock_t *ssock) |
| { |
| ossl_sock_t *ossock = (ossl_sock_t *)ssock; |
| + |
| + /* Detach from SSL instance */ |
| + if (ossock->ossl_ssl) { |
| + SSL_set_ex_data(ossock->ossl_ssl, sslsock_idx, NULL); |
| + } |
| + |
| /** |
| * Avoid calling SSL_shutdown() if handshake wasn't completed. |
| * OpenSSL 1.0.2f complains if SSL_shutdown() is called during an |