BUG/MEDIUM: stconn: Don't forward shutdown to SE if iobuf is not empty

It is only an issue when the kernel splicing is used. The zero-copy
forwarding via the buffers is not affected. When a shutdown is received on
the producer side and some data are blocked in the pipe for a while, the
shutdown may be forwarded to the other side. Usually, in this case, the
shutdown must be scheduled, waiting all output data (from the channel and
the consumer's iobuf) are sent. But only the channel was considered.

The bug was introduced by commit 20c463955d ("MEDIUM: channel: don't look at
iobuf to report an empty channel"). To fix the issue, we must also check
data blocked in the consummer iobuf.

This patch should solve the issue #2505. It must be backported to 2.9.

diff --git a/src/stconn.c b/src/stconn.c
index 0383e240484e7d3582f6a5a0ed19b38ac4de70e3..acfa6cc3958f08fd3738fa238e294b8c50238073 100644 (file)
--- a/src/stconn.c
+++ b/src/stconn.c
@@ -531,7 +531,7 @@ static inline int sc_cond_forward_shut(struct stconn *sc)
        if (!(sc->flags & (SC_FL_EOS|SC_FL_ABRT_DONE)) || !(sc->flags & SC_FL_NOHALF))
                return 0;
 
-       if (co_data(sc_ic(sc)) && !(sc_ic(sc)->flags & CF_WRITE_TIMEOUT)) {
+       if ((co_data(sc_ic(sc)) || sc_ep_have_ff_data(sc_opposite(sc))) && !(sc_ic(sc)->flags & CF_WRITE_TIMEOUT)) {
                /* the shutdown cannot be forwarded now because
                 * we should flush outgoing data first. But instruct the output
                 * channel it should be done ASAP.
@@ -1067,7 +1067,7 @@ void sc_notify(struct stconn *sc)
        struct task *task = sc_strm_task(sc);
 
        /* process consumer side */
-       if (!co_data(oc)) {
+       if (!co_data(oc) && !sc_ep_have_ff_data(sco)) {
                struct connection *conn = sc_conn(sc);
 
                if (((sc->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) == SC_FL_SHUT_WANTED) &&

diff --git a/src/stream.c b/src/stream.c
index 9d99d2f6b30a5bd6de236d36af200bc4917c8055..7052f7c30a67144ac201064ee9ef2fdd7db4f249 100644 (file)
--- a/src/stream.c
+++ b/src/stream.c
@@ -2369,7 +2369,7 @@ struct task *process_stream(struct task *t, void *context, unsigned int state)
 
        /* shutdown(write) pending */
        if (unlikely((scb->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) == SC_FL_SHUT_WANTED &&
-                    (!co_data(req) || (req->flags & CF_WRITE_TIMEOUT)))) {
+                    ((!co_data(req) && !sc_ep_have_ff_data(scb)) || (req->flags & CF_WRITE_TIMEOUT)))) {
                if (scf->flags & SC_FL_ERROR)
                        scb->flags |= SC_FL_NOLINGER;
                sc_shutdown(scb);
@@ -2477,7 +2477,7 @@ struct task *process_stream(struct task *t, void *context, unsigned int state)
 
        /* shutdown(write) pending */
        if (unlikely((scf->flags & (SC_FL_SHUT_DONE|SC_FL_SHUT_WANTED)) == SC_FL_SHUT_WANTED &&
-                    (!co_data(res) || (res->flags & CF_WRITE_TIMEOUT)))) {
+                    ((!co_data(res) && !sc_ep_have_ff_data(scf)) || (res->flags & CF_WRITE_TIMEOUT)))) {
                sc_shutdown(scf);
        }