Reset the rwstate before calling ASYNC_start_job()

If an async job pauses while processing a TLS connection then the
rwstate gets set to SSL_ASYNC_PAUSED. When resuming the job we should
reset the rwstate back to SSL_NOTHING. In fact we can do this
unconditionally since if we're about to call ASYNC_start_job() then either
we are about to start the async job for the first time (in which case the
rwstate should already by SSL_NOTHING), or we are restarting it after a
pause (in which case reseting it to SSL_NOTHING is the correct action).

Fixes #16809

Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17013)

(cherry picked from commit 07f620e3acf0dd76a3a03ada9911c544aa483aa7)

diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
index 501977f02c063c543e52b88550cfa17560b7a073..f497d83ecd7e2fccd79ed195675b522ba0e5a1cd 100644 (file)
--- a/ssl/ssl_lib.c
+++ b/ssl/ssl_lib.c
@@ -1770,6 +1770,8 @@ static int ssl_start_async_job(SSL *s, struct ssl_async_args *args,
                  (s->waitctx, ssl_async_wait_ctx_cb, s))
             return -1;
     }
+
+    s->rwstate = SSL_NOTHING;
     switch (ASYNC_start_job(&s->job, s->waitctx, &ret, func, args,
                             sizeof(struct ssl_async_args))) {
     case ASYNC_ERR: