Fix: off-by-one in comm proto between lttng-ctl and sessiond

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

diff --git a/src/common/consumer.c b/src/common/consumer.c
index f4eaf705f0b811230d0a9bb1f2f74458c7f7e6d0..53806b08d8ee4a0dcd54b80ee71edaca221fd784 100644 (file)
--- a/src/common/consumer.c
+++ b/src/common/consumer.c
@@ -345,7 +345,8 @@ struct lttng_consumer_stream *consumer_allocate_stream(
                uid_t uid,
                gid_t gid,
                int net_index,
-               int metadata_flag)
+               int metadata_flag,
+               int *alloc_ret)
 {
        struct lttng_consumer_stream *stream;
        int ret;
@@ -353,12 +354,13 @@ struct lttng_consumer_stream *consumer_allocate_stream(
        stream = zmalloc(sizeof(*stream));
        if (stream == NULL) {
                perror("malloc struct lttng_consumer_stream");
-               goto end;
+               *alloc_ret = -ENOMEM;
+               return NULL;
        }
        stream->chan = consumer_find_channel(channel_key);
        if (!stream->chan) {
-               perror("Unable to find channel key");
-               goto end;
+               *alloc_ret = -ENOENT;
+               goto error;
        }
        stream->chan->refcount++;
        stream->key = stream_key;
@@ -387,14 +389,14 @@ struct lttng_consumer_stream *consumer_allocate_stream(
                stream->cpu = stream->chan->cpucount++;
                ret = lttng_ustconsumer_allocate_stream(stream);
                if (ret) {
-                       free(stream);
-                       return NULL;
+                       *alloc_ret = -EINVAL;
+                       goto error;
                }
                break;
        default:
                ERR("Unknown consumer_data type");
-               assert(0);
-               goto end;
+               *alloc_ret = -EINVAL;
+               goto error;
        }
 
        /*
@@ -413,9 +415,11 @@ struct lttng_consumer_stream *consumer_allocate_stream(
                        stream->shm_fd, stream->wait_fd,
                        (unsigned long long) stream->mmap_len, stream->out_fd,
                        stream->net_seq_idx);
-
-end:
        return stream;
+
+error:
+       free(stream);
+       return NULL;
 }
 
 /*
@@ -1719,20 +1723,13 @@ restart:
                                        close(ctx->consumer_metadata_pipe[0]);
                                        continue;
                                } else if (revents & LPOLLIN) {
-                                       stream = zmalloc(sizeof(struct lttng_consumer_stream));
-                                       if (stream == NULL) {
-                                               PERROR("zmalloc metadata consumer stream");
-                                               goto error;
-                                       }
-
                                        do {
-                                               /* Get the stream and add it to the local hash table */
-                                               ret = read(pollfd, stream,
-                                                               sizeof(struct lttng_consumer_stream));
+                                               /* Get the stream pointer received */
+                                               ret = read(pollfd, &stream, sizeof(stream));
                                        } while (ret < 0 && errno == EINTR);
-                                       if (ret < 0 || ret < sizeof(struct lttng_consumer_stream)) {
+                                       if (ret < 0 ||
+                                                       ret < sizeof(struct lttng_consumer_stream *)) {
                                                PERROR("read metadata stream");
-                                               free(stream);
                                                /*
                                                 * Let's continue here and hope we can still work
                                                 * without stopping the consumer. XXX: Should we?