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 8f4f07a2088f75fbe0774bb240eb1d887806d958..c8f2ef5f49cc8d75a2d6fb82d49383294862cb91 100644 (file)
--- a/src/common/relayd/relayd.c
+++ b/src/common/relayd/relayd.c
@@ -255,8 +255,16 @@ 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));
-               strncpy(msg.channel_name, channel_name, sizeof(msg.channel_name));
-               strncpy(msg.pathname, pathname, sizeof(msg.pathname));
+               if (lttng_strncpy(msg.channel_name, channel_name,
+                               sizeof(msg.channel_name))) {
+                       ret = -1;
+                       goto error;
+               }
+               if (lttng_strncpy(msg.pathname, pathname,
+                               sizeof(msg.pathname))) {
+                       ret = -1;
+                       goto error;
+               }
 
                /* Send command */
                ret = send_command(rsock, RELAYD_ADD_STREAM, (void *) &msg, sizeof(msg), 0);
@@ -266,8 +274,16 @@ 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+ */
-               strncpy(msg_2_2.channel_name, channel_name, sizeof(msg_2_2.channel_name));
-               strncpy(msg_2_2.pathname, pathname, sizeof(msg_2_2.pathname));
+               if (lttng_strncpy(msg_2_2.channel_name, channel_name,
+                               sizeof(msg_2_2.channel_name))) {
+                       ret = -1;
+                       goto error;
+               }
+               if (lttng_strncpy(msg_2_2.pathname, pathname,
+                               sizeof(msg_2_2.pathname))) {
+                       ret = -1;
+                       goto error;
+               }
                msg_2_2.tracefile_size = htobe64(tracefile_size);
                msg_2_2.tracefile_count = htobe64(tracefile_count);