From: Willy Tarreau <w@1wt.eu>
Date: Fri, 28 Aug 2020 16:45:01 +0000 (+0200)
Subject: BUG/MINOR: reload: do not fail when no socket is sent
X-Git-Tag: v2.3-dev4~67
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=febbce87baf15b610d30172e37b98133e92159cc;p=thirdparty%2Fhaproxy.git

BUG/MINOR: reload: do not fail when no socket is sent

get_old_sockets() mistakenly sets ret=0 instead of ret2=0 before leaving
when the old process announces zero FD. So it will return an error
instead of success. This must be particularly rare not to have a
single socket to offer though!

A few comments were added to make it more obvious what to expect in
return.

This must be backported to 1.8 since the bug has always been there.
---

diff --git a/src/haproxy.c b/src/haproxy.c
index a8d27f84e1..03a05cdd48 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -1122,6 +1122,10 @@ next_dir_entry:
 	free(err);
 }
 
+/* Retrieves old sockets from worker process running the CLI at address
+ * <unixsocket>. Fills xfer_sock_list with what is found. Returns 0 on
+ * success, -1 on failure.
+ */
 static int get_old_sockets(const char *unixsocket)
 {
 	char *cmsgbuf = NULL, *tmpbuf = NULL;
@@ -1173,7 +1177,7 @@ static int get_old_sockets(const char *unixsocket)
 		goto out;
 	}
 	if (fd_nb == 0) {
-		ret = 0;
+		ret2 = 0;
 		goto out;
 	}
 	tmpbuf = malloc(fd_nb * (1 + MAXPATHLEN + 1 + IFNAMSIZ + sizeof(int)));