BUG/MEDIUM: mux-h1: Don't request more room on partial trailers
authorChristopher Faulet <cfaulet@haproxy.com>
Wed, 13 Apr 2022 15:48:54 +0000 (17:48 +0200)
committerChristopher Faulet <cfaulet@haproxy.com>
Fri, 29 Apr 2022 13:49:18 +0000 (15:49 +0200)
The commit 744451c7c ("BUG/MEDIUM: mux-h1: Properly detect full buffer cases
during message parsing") introduced a regression if trailers are not
received in one time. Indeed, in this case, nothing is appended in the
channel buffer, while there are some data in the input buffer. In this case,
we must not request more room to the upper layer, especially because the
channel buffer can be empty.

To fix the issue, on trailers parsing, we consider the H1 stream as
congested when the max size allowed is reached. Of course, the H1 stream is
also considered as congested if the trailers are too big and the channel
buffer is not empty.

This patch should fix the issue #1657. It must be backported as far as 2.0.

(cherry picked from commit ae660be547eb72b5c213d87769e60c527fe6b7cd)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit ce029039bc13f5896ad8fea3084a4e821ce2efa7)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 5d0efb7d523dff64c34320f36082b3ff04e096e2)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>

src/h1_htx.c
src/mux_h1.c

index 9e34076..3ee735b 100644 (file)
@@ -573,8 +573,14 @@ int h1_parse_msg_tlrs(struct h1m *h1m, struct htx *dsthtx,
        struct h1m tlr_h1m;
        int ret = 0;
 
-       if (!max || !b_data(srcbuf))
+       if (b_data(srcbuf) == ofs) {
+               /* Nothing to parse */
                goto end;
+       }
+       if (!max) {
+               /* No more room */
+               goto output_full;
+       }
 
        /* Realing input buffer if necessary */
        if (b_peek(srcbuf, ofs) > b_tail(srcbuf))
index a8821e7..89cc88d 100644 (file)
@@ -1389,7 +1389,7 @@ static size_t h1_process_trailers(struct h1s *h1s, struct h1m *h1m, struct htx *
                        TRACE_STATE("parsing error", H1_EV_RX_DATA|H1_EV_RX_TLRS|H1_EV_H1S_ERR, h1s->h1c->conn, h1s);
                        h1_capture_bad_message(h1s->h1c, h1s, h1m, buf);
                }
-               else if (ret == -2 || b_data(buf) != *ofs) {
+               else if (ret == -2) {
                        TRACE_STATE("RX path congested, waiting for more space", H1_EV_RX_DATA|H1_EV_RX_TLRS|H1_EV_H1S_BLK, h1s->h1c->conn, h1s);
                        h1s->flags |= H1S_F_RX_CONGESTED;
                }