From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Thu, 16 Jul 2020 16:39:20 +0000 (-0400)
Subject: Fix: relayd: send_viewer_streams sends stack data in padding
X-Git-Tag: v2.11.5~10
X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=198083871a1e3b68d62a445a7ad3f008c92103c6

Fix: relayd: send_viewer_streams sends stack data in padding

A single stack-allocated instance of `struct lttng_viewer_stream` is
used to send the various streams to the live viewer. This structure
contains a path and channel name which remain uninitialized beyond the
null terminator.

The structure is zeroed on every iteration.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I1c60ee18e01e8f56157f0fe44bd3bd64b1194703
---

diff --git a/src/bin/lttng-relayd/live.c b/src/bin/lttng-relayd/live.c
index 1b25671d5..75c022707 100644
--- a/src/bin/lttng-relayd/live.c
+++ b/src/bin/lttng-relayd/live.c
@@ -200,7 +200,6 @@ ssize_t send_viewer_streams(struct lttcomm_sock *sock,
 		uint64_t session_id, unsigned int ignore_sent_flag)
 {
 	ssize_t ret;
-	struct lttng_viewer_stream send_stream;
 	struct lttng_ht_iter iter;
 	struct relay_viewer_stream *vstream;
 
@@ -209,6 +208,7 @@ ssize_t send_viewer_streams(struct lttcomm_sock *sock,
 	cds_lfht_for_each_entry(viewer_streams_ht->ht, &iter.iter, vstream,
 			stream_n.node) {
 		struct ctf_trace *ctf_trace;
+		struct lttng_viewer_stream send_stream = {};
 
 		health_code_update();