lib-ssl-iostream: ostream-openssl - Prevent segfault o_stream_get_buffer_*_size(...

diff --git a/src/lib-ssl-iostream/ostream-openssl.c b/src/lib-ssl-iostream/ostream-openssl.c
index d1518bc5d7264115b90d9acb14e171e836e985e2..ed80bf0acf68fdcaa57fc8c3f5a4d0a1a0a3255b 100644 (file)
--- a/src/lib-ssl-iostream/ostream-openssl.c
+++ b/src/lib-ssl-iostream/ostream-openssl.c
@@ -36,12 +36,16 @@ static void o_stream_ssl_destroy(struct iostream_private *stream)
 static size_t get_buffer_avail_size(const struct ssl_ostream *sstream)
 {
        if (sstream->ostream.max_buffer_size == 0) {
+               if (sstream->buffer == NULL)
+                       return 0;
                /* we're requested to use whatever space is available in
                   the buffer */
                return buffer_get_writable_size(sstream->buffer) - sstream->buffer->used;
        } else {
-               return sstream->ostream.max_buffer_size > sstream->buffer->used ?
-                       sstream->ostream.max_buffer_size - sstream->buffer->used : 0;
+               size_t buffer_used = (sstream->buffer == NULL ? 0 :
+                                     sstream->buffer->used);
+               return sstream->ostream.max_buffer_size > buffer_used ?
+                       sstream->ostream.max_buffer_size - buffer_used : 0;
        }
 }
 
@@ -53,7 +57,7 @@ o_stream_ssl_buffer(struct ssl_ostream *sstream, const struct const_iovec *iov,
        unsigned int i;
 
        if (sstream->buffer == NULL)
-               sstream->buffer = buffer_create_dynamic(default_pool, 4096);
+               sstream->buffer = buffer_create_dynamic(default_pool, sstream->ostream.max_buffer_size);
 
        skip_left = bytes_sent;
        for (i = 0; i < iov_count; i++) {
@@ -212,9 +216,10 @@ o_stream_ssl_get_buffer_used_size(const struct ostream_private *stream)
        BIO *bio = SSL_get_wbio(sstream->ssl_io->ssl);
        size_t wbuf_avail = BIO_ctrl_get_write_guarantee(bio);
        size_t wbuf_total_size = BIO_get_write_buf_size(bio, 0);
-
+       size_t buffer_used = (sstream->buffer == NULL ? 0 :
+                             sstream->buffer->used);
        i_assert(wbuf_avail <= wbuf_total_size);
-       return sstream->buffer->used + (wbuf_total_size - wbuf_avail) +
+       return buffer_used + (wbuf_total_size - wbuf_avail) +
                o_stream_get_buffer_used_size(sstream->ssl_io->plain_output);
 }