This makes a number of changes to improve error reporting while connecting
a new spliced socket:
* We use flow_err() and similar functions so all messages include info
on which specific flow was affected
* We use strerror() to interpret raw error values
* We now report errors on connection (at "trace" level, since this would
allow spamming the logs)
* We also look up and report some details on EPOLLERR events, which can
include connection errors, since we use a non-blocking connect(). Again
we use "trace" level since this can spam the logs.
* Use the 'goto fail' idiom in tcp_splice_conn_from_sock to combine some
common handling
Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au>
---
tcp_splice.c | 36 +++++++++++++++++++++++++++++-------
1 file changed, 29 insertions(+), 7 deletions(-)
diff --git a/tcp_splice.c b/tcp_splice.c
index 30b4d58a..abd698d4 100644
--- a/tcp_splice.c
+++ b/tcp_splice.c
@@ -387,7 +387,7 @@ bool tcp_splice_conn_from_sock(const struct ctx *c,
in_port_t srcport, dstport = ref.port;
union inany_addr src;
sa_family_t af;
- int s1;
+ int s1, rc;
ASSERT(c->mode == MODE_PASTA);
@@ -420,15 +420,25 @@ bool tcp_splice_conn_from_sock(const struct ctx *c,
}
if (s1 < 0) {
- warn("Couldn't open connectable socket for splice (%d)", s1);
- conn_flag(c, conn, CLOSING);
- return true;
+ flow_err(conn,
+ "Couldn't open connectable socket for splice: %s",
+ strerror(-s1));
+ goto fail;
}
- if (tcp_splice_connect(c, conn, s1, dstport))
- conn_flag(c, conn, CLOSING);
+ if ((rc = tcp_splice_connect(c, conn, s1, dstport))) {
+ flow_trace(conn, "Couldn't connect socket for splice: %s",
+ strerror(-rc));
+ goto fail;
+ }
return true;
+
+fail:
+ /* This is *supposed* to be a spliced connection, but something went
+ * wrong */
+ conn_flag(c, conn, CLOSING);
+ return true;
}
/**
@@ -452,8 +462,20 @@ void tcp_splice_sock_handler(struct ctx *c, union epoll_ref ref,
if (conn->events == SPLICE_CLOSED)
return;
- if (events & EPOLLERR)
+ if (events & EPOLLERR) {
+ int err, rc;
+ socklen_t sl = sizeof(err);
+
+ rc = getsockopt(ref.fd, SOL_SOCKET, SO_ERROR, &err, &sl);
+ if (rc)
+ flow_err(conn, "Error retrieving SO_ERROR: %s",
+ strerror(errno));
+ else
+ flow_trace(conn, "Error event on socket: %s",
+ strerror(err));
+
goto close;
+ }
if (conn->events == SPLICE_CONNECT) {
if (!(events & EPOLLOUT))
--
2.43.0