[ulogd2 PATCH 14/26] input: UNIXSOCK: fix possible truncation of socket path

[Jeremy Sowden <jeremy@azazel.net>]

Verify that the path is short enough, and replace `strncpy` with `strcpy`.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
---
 input/packet/ulogd_inppkt_UNIXSOCK.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/input/packet/ulogd_inppkt_UNIXSOCK.c b/input/packet/ulogd_inppkt_UNIXSOCK.c
index d88609f203c4..af2fbeca1f4c 100644
--- a/input/packet/ulogd_inppkt_UNIXSOCK.c
+++ b/input/packet/ulogd_inppkt_UNIXSOCK.c
@@ -475,10 +475,19 @@ static int handle_packet(struct ulogd_pluginstance *upi, struct ulogd_unixsock_p
 static int _create_unix_socket(const char *unix_path)
 {
 	int ret = -1;
-	struct sockaddr_un server_sock;
+	struct sockaddr_un server_sock = { .sun_family = AF_UNIX };
 	int s;
 	struct stat st_dummy;
 
+	if (sizeof(server_sock.sun_path) <= strlen(unix_path)) {
+		ulogd_log(ULOGD_ERROR,
+			  "ulogd2: unix socket path '%s' too long\n",
+			  unix_path);
+		return -1;
+	}
+
+	strcpy(server_sock.sun_path, unix_path);
+
 	if (stat(unix_path, &st_dummy) == 0 && st_dummy.st_size > 0) {
 		ulogd_log(ULOGD_ERROR,
 			  "ulogd2: unix socket '%s' already exists\n",
@@ -493,10 +502,6 @@ static int _create_unix_socket(const char *unix_path)
 		return -1;
 	}
 
-	server_sock.sun_family = AF_UNIX;
-	strncpy(server_sock.sun_path, unix_path, sizeof(server_sock.sun_path));
-	server_sock.sun_path[sizeof(server_sock.sun_path)-1] = '\0';
-
 	ret = bind(s, (struct sockaddr *)&server_sock, sizeof(server_sock));
 	if (ret < 0) {
 		ulogd_log(ULOGD_ERROR,
-- 
2.33.0