Commit 02dfc930 authored by Tatsuhiro Tsujikawa's avatar Tatsuhiro Tsujikawa Committed by Daniel Stenberg
Browse files

http2: Copy data passed in Curl_http2_switched into HTTP/2 connection buffer 

Previously, after seeing upgrade to HTTP/2, we feed data followed by
upgrade response headers directly to nghttp2_session_mem_recv() in
Curl_http2_switched().  But it turns out that passed buffer, mem, is
part of stream->mem, and callbacks called by
nghttp2_session_mem_recv() will write stream specific data into
stream->mem, overwriting input data.  This will corrupt input, and
most likely frame length error is detected by nghttp2 library.  The
fix is first copy the passed data to HTTP/2 connection buffer,
httpc->inbuf, and call nghttp2_session_mem_recv().
parent 96c0164b

lib/http2.c

+33 −3
Original line number Diff line number Diff line
@@ -1248,6 +1248,7 @@ CURLcode Curl_http2_switched(struct connectdata *conn, 
  CURLcode result;

  struct http_conn *httpc = &conn->proto.httpc;

  int rv;

  ssize_t nproc;

  struct SessionHandle *data = conn->data;

  struct HTTP *stream = conn->data->req.protop;
@@ -1290,14 +1291,43 @@ CURLcode Curl_http2_switched(struct connectdata *conn, 
    }

  }



  rv = (int)nghttp2_session_mem_recv(httpc->h2, (const uint8_t*)mem, nread);

  /* we are going to copy mem to httpc->inbuf.  This is required since

     mem is part of buffer pointed by stream->mem, and callbacks

     called by nghttp2_session_mem_recv() will write stream specific

     data into stream->mem, overwriting data already there. */

  if(H2_BUFSIZE < nread) {

    failf(data, "connection buffer size is too small to store data following "

                "HTTP Upgrade response header: buflen=%zu, datalen=%zu",

          H2_BUFSIZE, nread);

    return CURLE_HTTP2;

  }



  if(rv != (int)nread) {

  infof(conn->data, "Copying HTTP/2 data in stream buffer to connection buffer"

                    " after upgrade: len=%zu\n",

        nread);



  memcpy(httpc->inbuf, mem, nread);

  httpc->inbuflen = nread;



  nproc = nghttp2_session_mem_recv(httpc->h2, (const uint8_t *)httpc->inbuf,

                                   httpc->inbuflen);



  if(nghttp2_is_fatal((int)nproc)) {

    failf(data, "nghttp2_session_mem_recv() failed: %s(%d)",

          nghttp2_strerror(rv), rv);

          nghttp2_strerror((int)nproc), (int)nproc);

    return CURLE_HTTP2;

  }



  DEBUGF(infof(data, "nghttp2_session_mem_recv() returns %zd\n", nproc));



  if((ssize_t)nread == nproc) {

    httpc->inbuflen = 0;

    httpc->nread_inbuf = 0;

  }

  else {

    httpc->nread_inbuf += nproc;

  }



  /* Try to send some frames since we may read SETTINGS already. */

  rv = nghttp2_session_send(httpc->h2);