Fix: Possible buffer overflows in strncat() usage

[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index d36966322fc7278617109b9df471bda8196ea5cc..1b1f87b8e5f30e8a0b74877b246af59ba71d250d 100644 (file)
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -385,7 +385,8 @@ static int add_uri_to_consumer(struct consumer_output *consumer,
 
                if (uri->stype == LTTNG_STREAM_CONTROL) {
                        /* On a new subdir, reappend the default trace dir. */
-                       strncat(consumer->subdir, default_trace_dir, sizeof(consumer->subdir));
+                       strncat(consumer->subdir, default_trace_dir,
+                                       sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
                        DBG3("Append domain trace name to subdir %s", consumer->subdir);
                }
 
@@ -398,7 +399,8 @@ static int add_uri_to_consumer(struct consumer_output *consumer,
                                sizeof(consumer->dst.trace_path));
                /* Append default trace dir */
                strncat(consumer->dst.trace_path, default_trace_dir,
-                               sizeof(consumer->dst.trace_path));
+                               sizeof(consumer->dst.trace_path) -
+                               strlen(consumer->dst.trace_path) - 1);
                /* Flag consumer as local. */
                consumer->type = CONSUMER_DST_LOCAL;
                break;
@@ -2196,7 +2198,8 @@ int cmd_enable_consumer(int domain, struct ltt_session *session)
 
                /* Append default kernel trace dir to subdir */
                strncat(ksess->consumer->subdir, DEFAULT_KERNEL_TRACE_DIR,
-                               sizeof(ksess->consumer->subdir));
+                               sizeof(ksess->consumer->subdir) -
+                               strlen(ksess->consumer->subdir) - 1);
 
                /*
                 * @session-lock
@@ -2281,7 +2284,8 @@ int cmd_enable_consumer(int domain, struct ltt_session *session)
 
                /* Append default kernel trace dir to subdir */
                strncat(usess->consumer->subdir, DEFAULT_UST_TRACE_DIR,
-                               sizeof(usess->consumer->subdir));
+                               sizeof(usess->consumer->subdir) -
+                               strlen(usess->consumer->subdir) - 1);
 
                /*
                 * @session-lock