flowside_connect() behaves much like connect(2) itself, returning -1 on
error with errno set to the error code. One of the callers, in
udp_flow_sock(), uses the errno code with flow_dbg_perror() *after* it's
called epoll_del() and close() either of which could clobber errno.
Fix that by moving the debug message earlier: there's no reason it has to
wait until the epoll_del() and close().
While we're at it, adjust the comment on flowside_connect() to clarify
that it sets errno (rather than, say, returning an error code).
Suggested-by: Stefano Brivio
Signed-off-by: David Gibson
---
flow.c | 2 +-
udp_flow.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/flow.c b/flow.c
index b2963396..85ac6307 100644
--- a/flow.c
+++ b/flow.c
@@ -258,7 +258,7 @@ int flowside_sock_l4(const struct ctx *c, enum epoll_type type, uint8_t pif,
*
* Connect @s to the endpoint address and port from @tgt.
*
- * Return: 0 on success, negative on error
+ * Return: 0 on success, negative on error (setting errno)
*/
int flowside_connect(const struct ctx *c, int s,
uint8_t pif, const struct flowside *tgt)
diff --git a/udp_flow.c b/udp_flow.c
index 35417bc4..31e2f8a7 100644
--- a/udp_flow.c
+++ b/udp_flow.c
@@ -90,11 +90,11 @@ static int udp_flow_sock(const struct ctx *c,
if (flowside_connect(c, s, pif, side) < 0) {
rc = -errno;
+ flow_dbg_perror(uflow, "Couldn't connect flow socket");
epoll_del(flow_epollfd(&uflow->f), s);
close(s);
- flow_dbg_perror(uflow, "Couldn't connect flow socket");
return rc;
}
uflow->s[sidei] = s;
--
2.54.0