BUG/MEDIUM: channel: don't allow to overwrite the reserve until connected
Commit 9c06ee4 ("BUG/MEDIUM: channel: don't schedule data in transit for
leaving until connected") took care of an issue involving POST in conjunction
with http-send-name-header, where we absolutely never want to touch the
reserve until we're sure not to touch the buffer contents anymore, which
is indicated by the output stream-interface being connected.
But channel_may_recv() was not equipped with such a test, so in some
situations it might decide that it is possible to poll for reads, and
later channel_recv_limit() will decide it's not possible to read,
causing a loop. So we must add a similar test there.
Since the fix above was backported to 1.6 and 1.5, this fix must as well.
(cherry picked from commit 4b46a3e8cce58db03ee90718e39fb3bffb2b7273)
(cherry picked from commit c2c825aed3c76ed9747e47c1078c71ddcb9d06ad)
[wt: note in 1.5 channel_full() returns the opposite value of 1.6's]
diff --git a/include/proto/channel.h b/include/proto/channel.h
index 9e02dc0..3d8a1b7 100644
--- a/include/proto/channel.h
+++ b/include/proto/channel.h
@@ -134,7 +134,9 @@
* end of transfer is close to happen. Note that both ->buf->o and ->to_forward
* are considered as available since they're supposed to leave the buffer. The
* test is optimized to avoid as many operations as possible for the fast case
- * and to be used as an "if" condition.
+ * and to be used as an "if" condition. Just like channel_recv_limit(), we
+ * never allow to overwrite the reserve until the output stream interface is
+ * connected, otherwise we could spin on a POST with http-send-name-header.
*/
static inline int channel_full(const struct channel *chn)
{
@@ -145,6 +147,9 @@
if (!rem)
return 1; /* buffer already full */
+ if (rem <= global.tune.maxrewrite && !channel_may_send(chn))
+ return 1;
+
/* now we know there's some room left, verify if we're touching
* the reserve with some permanent input data.
*/