Fix: Off by uint64_t in the metadata transfer

[lttng-tools.git] / src / common / ust-consumer / ust-consumer.c

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index f6add2c2c88327d05f1dd1ce90b49241df74c1f8..a57bf15987d28061bf56a994dfacc0ad882c6ecd 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -56,10 +56,15 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
        uint64_t metadata_id;
        struct consumer_relayd_sock_pair *relayd = NULL;
 
+       /* RCU lock for the relayd pointer */
+       rcu_read_lock();
+
        /* Flag that the current stream if set for network streaming. */
        if (stream->net_seq_idx != -1) {
                relayd = consumer_find_relayd(stream->net_seq_idx);
                if (relayd == NULL) {
+                       ERR("UST consumer mmap(), unable to find relay for index %d",
+                                       stream->net_seq_idx);
                        goto end;
                }
        }
@@ -91,12 +96,12 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
                                do {
                                        ret = write(outfd, (void *) &metadata_id,
                                                        sizeof(stream->relayd_stream_id));
-                                       if (ret < 0) {
-                                               PERROR("write metadata stream id");
-                                               written = ret;
-                                               goto end;
-                                       }
-                               } while (errno == EINTR);
+                               } while (ret < 0 && errno == EINTR);
+                               if (ret < 0) {
+                                       PERROR("write metadata stream id");
+                                       written = ret;
+                                       goto end;
+                               }
                                DBG("Metadata stream id %zu written before data",
                                                stream->relayd_stream_id);
                        }
@@ -105,18 +110,15 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
        }
 
        while (len > 0) {
-               ret = write(outfd, stream->mmap_base + mmap_offset, len);
+               do {
+                       ret = write(outfd, stream->mmap_base + mmap_offset, len);
+               } while (ret < 0 && errno == EINTR);
                if (ret < 0) {
-                       if (errno == EINTR) {
-                               /* restart the interrupted system call */
-                               continue;
-                       } else {
-                               PERROR("Error in file write");
-                               if (written == 0) {
-                                       written = ret;
-                               }
-                               goto end;
+                       PERROR("Error in file write");
+                       if (written == 0) {
+                               written = ret;
                        }
+                       goto end;
                } else if (ret > len) {
                        PERROR("ret %ld > len %lu", ret, len);
                        written += ret;
@@ -142,6 +144,7 @@ end:
        if (relayd && stream->metadata_flag) {
                pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
        }
+       rcu_read_unlock();
        return written;
 }
 
@@ -213,6 +216,9 @@ int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                return -ENOENT;
        }
 
+       /* relayd need RCU read-side lock */
+       rcu_read_lock();
+
        switch (msg.cmd_type) {
        case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
        {
@@ -434,8 +440,9 @@ end:
         */
        do {
                ret = write(ctx->consumer_poll_pipe[1], "", 1);
-       } while (ret == -1UL && errno == EINTR);
+       } while (ret < 0 && errno == EINTR);
 end_nosignal:
+       rcu_read_unlock();
        return 0;
 }