Create all trace directories and files with client user credentials

[lttng-tools.git] / lttng-sessiond / ust-consumer.c

diff --git a/lttng-sessiond/ust-consumer.c b/lttng-sessiond/ust-consumer.c
index ca008d4adf65d0165d3eaca6f06f149361081594..b87d61120faa2473f7d42a9609a432e31bc7bebf 100644 (file)
--- a/lttng-sessiond/ust-consumer.c
+++ b/lttng-sessiond/ust-consumer.c
@@ -34,11 +34,12 @@
  * Send all stream fds of UST channel to the consumer.
  */
 static int send_channel_streams(int sock,
-               struct ust_app_channel *uchan)
+               struct ust_app_channel *uchan,
+               uid_t uid, gid_t gid)
 {
        int ret, fd;
        struct lttcomm_consumer_msg lum;
-       struct ltt_ust_stream *stream;
+       struct ltt_ust_stream *stream, *tmp;
 
        DBG("Sending streams of channel %s to UST consumer", uchan->name);
 
@@ -46,8 +47,11 @@ static int send_channel_streams(int sock,
        lum.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
 
        /*
-        * We need to keep shm_fd open to make sure this key stays unique within
-        * the session daemon.
+        * We need to keep shm_fd open while we transfer the stream file
+        * descriptors to make sure this key stays unique within the
+        * session daemon. We can free the channel shm_fd without
+        * problem after we finished sending stream fds for that
+        * channel.
         */
        lum.u.channel.channel_key = uchan->obj->shm_fd;
        lum.u.channel.max_sb_size = uchan->attr.subbuf_size;
@@ -65,7 +69,7 @@ static int send_channel_streams(int sock,
                goto error;
        }
 
-       cds_list_for_each_entry(stream, &uchan->streams.head, list) {
+       cds_list_for_each_entry_safe(stream, tmp, &uchan->streams.head, list) {
                int fds[2];
 
                if (!stream->obj->shm_fd) {
@@ -81,6 +85,8 @@ static int send_channel_streams(int sock,
                 */
                lum.u.stream.output = DEFAULT_UST_CHANNEL_OUTPUT;
                lum.u.stream.mmap_len = stream->obj->memory_map_size;
+               lum.u.stream.uid = uid;
+               lum.u.stream.gid = gid;
                strncpy(lum.u.stream.path_name, stream->pathname, PATH_MAX - 1);
                lum.u.stream.path_name[PATH_MAX - 1] = '\0';
                DBG("Sending stream %d to consumer", lum.u.stream.stream_key);
@@ -121,6 +127,11 @@ int ust_consumer_send_session(int consumer_fd, struct ust_app_session *usess)
 
        DBG("Sending metadata stream fd");
 
+       if (consumer_fd < 0) {
+               ERR("Consumer has negative file descriptor");
+               return -EINVAL;
+       }
+
        if (usess->metadata->obj->shm_fd != 0) {
                int fd;
                int fds[2];
@@ -150,6 +161,8 @@ int ust_consumer_send_session(int consumer_fd, struct ust_app_session *usess)
                lum.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
                lum.u.stream.output = DEFAULT_UST_CHANNEL_OUTPUT;
                lum.u.stream.mmap_len = usess->metadata->stream_obj->memory_map_size;
+               lum.u.stream.uid = usess->uid;
+               lum.u.stream.gid = usess->gid;
                strncpy(lum.u.stream.path_name, usess->metadata->pathname, PATH_MAX - 1);
                lum.u.stream.path_name[PATH_MAX - 1] = '\0';
                DBG("Sending metadata stream %d to consumer", lum.u.stream.stream_key);
@@ -173,7 +186,8 @@ int ust_consumer_send_session(int consumer_fd, struct ust_app_session *usess)
        while ((node = hashtable_iter_get_node(&iter)) != NULL) {
                uchan = caa_container_of(node, struct ust_app_channel, node);
 
-               ret = send_channel_streams(sock, uchan);
+               ret = send_channel_streams(sock, uchan, usess->uid,
+                               usess->gid);
                if (ret < 0) {
                        rcu_read_unlock();
                        goto error;