[PATCH net 7/7] selftests: ovpn: avoid calling freeaddrinfo() on NULL

[Antonio Quartulli <antonio@openvpn.net>]

ovpn_parse_remote() always calls freeaddrinfo() on its exit path, but
result is NULL when no vpnip was passed (with or without a remote host).

POSIX does not allow passing NULL to freeaddrinfo(). glibc tolerates
it, while musl dereferences the pointer and ovpn-cli segfaults.

Only free result when getaddrinfo() actually returned a list.

Fixes: 959bc330a439 ("testing/selftests: add test tool and scripts for ovpn module")
Cc: stable@vger.kernel.org
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
 tools/testing/selftests/net/ovpn/ovpn-cli.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/net/ovpn/ovpn-cli.c b/tools/testing/selftests/net/ovpn/ovpn-cli.c
index 3b612a8a18fe..ce9436f92b43 100644
--- a/tools/testing/selftests/net/ovpn/ovpn-cli.c
+++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c
@@ -1849,7 +1849,8 @@ static int ovpn_parse_remote(struct ovpn_ctx *ovpn, const char *host,
 
 	ret = 0;
 out:
-	freeaddrinfo(result);
+	if (result)
+		freeaddrinfo(result);
 	return ret;
 }