Fix: liblttng-ctl comm: lttng_event_field is not packed

[lttng-tools.git] / src / lib / lttng-ctl / lttng-ctl.cpp

diff --git a/src/lib/lttng-ctl/lttng-ctl.cpp b/src/lib/lttng-ctl/lttng-ctl.cpp
index e671bae402c3d21927fc41ad17445a0778e192dc..c7fb313f90fb1eedfa0541b1014d8209473fd23e 100644 (file)
--- a/src/lib/lttng-ctl/lttng-ctl.cpp
+++ b/src/lib/lttng-ctl/lttng-ctl.cpp
@@ -1715,23 +1715,74 @@ end:
 int lttng_list_tracepoint_fields(struct lttng_handle *handle,
                struct lttng_event_field **fields)
 {
+       enum lttng_error_code ret_code;
        int ret;
        struct lttcomm_session_msg lsm;
+       const struct lttcomm_list_command_header *cmd_header = NULL;
+       unsigned int nb_event_fields = 0;
+       struct lttng_payload reply;
 
        if (handle == NULL) {
-               return -LTTNG_ERR_INVALID;
+               ret = -LTTNG_ERR_INVALID;
+               goto end;
        }
 
+       lttng_payload_init(&reply);
+
        memset(&lsm, 0, sizeof(lsm));
        lsm.cmd_type = LTTNG_LIST_TRACEPOINT_FIELDS;
        COPY_DOMAIN_PACKED(lsm.domain, handle->domain);
 
-       ret = lttng_ctl_ask_sessiond(&lsm, (void **) fields);
-       if (ret < 0) {
-               return ret;
+       {
+               lttng_payload_view message_view =
+                               lttng_payload_view_init_from_buffer(
+                                       (const char *) &lsm, 0,
+                                       sizeof(lsm));
+
+               ret = lttng_ctl_ask_sessiond_payload(&message_view, &reply);
+               if (ret < 0) {
+                       goto end;
+               }
+       }
+
+       {
+               const lttng_buffer_view cmd_header_view =
+                               lttng_buffer_view_from_dynamic_buffer(
+                                       &reply.buffer, 0, sizeof(*cmd_header));
+
+               if (!lttng_buffer_view_is_valid(&cmd_header_view)) {
+                       ret = -LTTNG_ERR_INVALID_PROTOCOL;
+                       goto end;
+               }
+
+               cmd_header = (struct lttcomm_list_command_header *)
+                               cmd_header_view.data;
+       }
+
+       if (cmd_header->count > INT_MAX) {
+               ret = -LTTNG_ERR_OVERFLOW;
+               goto end;
+       }
+
+       nb_event_fields = cmd_header->count;
+
+       {
+               lttng_payload_view reply_view =
+                               lttng_payload_view_from_payload(&reply,
+                               sizeof(*cmd_header), -1);
+
+               ret_code = lttng_event_fields_create_and_flatten_from_payload(
+                               &reply_view, nb_event_fields, fields);
+               if (ret_code != LTTNG_OK) {
+                       ret = -ret_code;
+                       goto end;
+               }
        }
 
-       return ret / sizeof(struct lttng_event_field);
+       ret = nb_event_fields;
+
+end:
+       return ret;
 }
 
 /*