Fix: illegal memory access in relayd_add_stream

Found by Coverity:

CID 1243017 (#1 of 4): Buffer not null terminated
(BUFFER_SIZE_WARNING)14. buffer_size_warning: Calling strncpy with a
maximum size argument of 264 bytes on destination array msg.channel_name
of size 264 bytes might leave the destination string unterminated.

ID 1243017 (#2 of 4): Buffer not null terminated
(BUFFER_SIZE_WARNING)14. buffer_size_warning: Calling strncpy with a
maximum size argument of 264 bytes on destination array
msg_2_2.channel_name of size 264 bytes might leave the destination
string unterminated.

CID 1243017 (#3 of 4): Buffer not null terminated
(BUFFER_SIZE_WARNING)15. buffer_size_warning: Calling strncpy with a
maximum size argument of 4096 bytes on destination array msg.pathname of
size 4096 bytes might leave the destination string unterminated.

CID 1243017 (#4 of 4): Buffer not null terminated
(BUFFER_SIZE_WARNING)15. buffer_size_warning: Calling strncpy with a
maximum size argument of 4096 bytes on destination array
msg_2_2.pathname of size 4096 bytes might leave the destination string
unterminated.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/src/common/relayd/relayd.c b/src/common/relayd/relayd.c
index 9e9525503a971dc993237aae1cfdf9188bdc29f4..7f0ea74e94085b99873049a736941015e85fda5c 100644 (file)
--- a/src/common/relayd/relayd.c
+++ b/src/common/relayd/relayd.c
@@ -254,16 +254,16 @@ int relayd_add_stream(struct lttcomm_relayd_sock *rsock, const char *channel_nam
        /* Compat with relayd 2.1 */
        if (rsock->minor == 1) {
                memset(&msg, 0, sizeof(msg));
-               if (strlen(channel_name) >= sizeof(msg.channel_name)) {
+               if (lttng_strncpy(msg.channel_name, channel_name,
+                               sizeof(msg.channel_name))) {
                        ret = -1;
                        goto error;
                }
-               strncpy(msg.channel_name, channel_name, sizeof(msg.channel_name));
-               if (strlen(pathname) >= sizeof(msg.pathname)) {
+               if (lttng_strncpy(msg.pathname, pathname,
+                               sizeof(msg.pathname))) {
                        ret = -1;
                        goto error;
                }
-               strncpy(msg.pathname, pathname, sizeof(msg.pathname));
 
                /* Send command */
                ret = send_command(rsock, RELAYD_ADD_STREAM, (void *) &msg, sizeof(msg), 0);
@@ -273,16 +273,16 @@ int relayd_add_stream(struct lttcomm_relayd_sock *rsock, const char *channel_nam
        } else {
                memset(&msg_2_2, 0, sizeof(msg_2_2));
                /* Compat with relayd 2.2+ */
-               if (strlen(channel_name) >= sizeof(msg_2_2.channel_name)) {
+               if (lttng_strncpy(msg_2_2.channel_name, channel_name,
+                               sizeof(msg_2_2.channel_name))) {
                        ret = -1;
                        goto error;
                }
-               strncpy(msg_2_2.channel_name, channel_name, sizeof(msg_2_2.channel_name));
-               if (strlen(pathname) >= sizeof(msg_2_2.pathname)) {
+               if (lttng_strncpy(msg_2_2.pathname, pathname,
+                               sizeof(msg_2_2.pathname))) {
                        ret = -1;
                        goto error;
                }
-               strncpy(msg_2_2.pathname, pathname, sizeof(msg_2_2.pathname));
                msg_2_2.tracefile_size = htobe64(tracefile_size);
                msg_2_2.tracefile_count = htobe64(tracefile_count);