poky/meta/recipes-kernel/lttng/lttng-modules/0001-Fix-memory-leaks-on-event-destroy.patch

From b3fdf78b15beb940918da1e41eb68e24ba31bb87 Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Wed, 3 Mar 2021 10:10:16 -0500
Subject: [PATCH 1/4] Fix: memory leaks on event destroy

Both filter runtime and event enabler ref objects are owned by the
event, but are not freed upon destruction of the event object, thus
leaking memory.

Upstream-status: backport

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ice9b1c18b47584838aea2b965494d3c8391f4c84
---
 lttng-events.c | 7 +++++++
 lttng-events.h | 1 +
 2 files changed, 8 insertions(+)

diff --git a/lttng-events.c b/lttng-events.c
index f3398adc..984bd341 100644
--- a/lttng-events.c
+++ b/lttng-events.c
@@ -919,6 +919,8 @@ int _lttng_event_unregister(struct lttng_event *event)
 static
 void _lttng_event_destroy(struct lttng_event *event)
 {
+	struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref;
+
 	switch (event->instrumentation) {
 	case LTTNG_KERNEL_TRACEPOINT:
 		lttng_event_put(event->desc);
@@ -944,6 +946,11 @@ void _lttng_event_destroy(struct lttng_event *event)
 	}
 	list_del(&event->list);
 	lttng_destroy_context(event->ctx);
+	lttng_free_event_filter_runtime(event);
+	/* Free event enabler refs */
+	list_for_each_entry_safe(enabler_ref, tmp_enabler_ref,
+				 &event->enablers_ref_head, node)
+		kfree(enabler_ref);
 	kmem_cache_free(event_cache, event);
 }
 
diff --git a/lttng-events.h b/lttng-events.h
index 1b9ab167..13b6abf5 100644
--- a/lttng-events.h
+++ b/lttng-events.h
@@ -716,6 +716,7 @@ int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
 		struct lttng_kernel_filter_bytecode __user *bytecode);
 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 		struct lttng_enabler *enabler);
+void lttng_free_event_filter_runtime(struct lttng_event *event);
 
 int lttng_probes_init(void);
 
-- 
2.19.1