From 8f2593fbbad2a549b854645acde7b11f5e02a924 Mon Sep 17 00:00:00 2001

From: Jerome Marchand <jmarchan@redhat.com>

Date: Thu, 6 Jun 2024 17:38:23 +0200

Subject: [PATCH 09/15] libtracefs: Prevent a memory leak in open_cpu_files()

In open_cpu_files(), if realloc() fails, the latest allocated tcpu

isn't freed. Rearrange the loop to prevent that.

Link: https://lore.kernel.org/linux-trace-devel/20240606153830.2666120-10-jmarchan@redhat.com

Fixes: 564bffddcb117 ("libtracefs: Use tracefs_cpu_read() for tracefs_iterate_raw_events()")

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

---

 src/tracefs-events.c | 10 +++++-----

 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/tracefs-events.c b/src/tracefs-events.c

index d65837e..88325e1 100644

--- a/src/tracefs-events.c

+++ b/src/tracefs-events.c

@@ -275,9 +275,12 @@ static int open_cpu_files(struct tracefs_instance *instance, cpu_set_t *cpus,

 			tcpu = tracefs_cpu_snapshot_open(instance, cpu, true);

 		else

 			tcpu = tracefs_cpu_open_mapped(instance, cpu, true);

+		if (!tcpu)

+			goto error;

+

 		tmp = realloc(*all_cpus, (i + 1) * sizeof(*tmp));

 		if (!tmp) {

-			i--;

+			tracefs_cpu_close(tcpu);

 			goto error;

 		}

@@ -285,9 +288,6 @@ static int open_cpu_files(struct tracefs_instance *instance, cpu_set_t *cpus,

 		memset(tmp + i, 0, sizeof(*tmp));

-		if (!tcpu)

-			goto error;

-

 		tmp[i].tcpu = tcpu;

 		tmp[i].cpu = cpu;

 		i++;

@@ -296,7 +296,7 @@ static int open_cpu_files(struct tracefs_instance *instance, cpu_set_t *cpus,

 	return 0;

  error:

 	tmp = *all_cpus;

-	for (; i >= 0; i--) {

+	for (i--; i >= 0; i--) {

 		tracefs_cpu_close(tmp[i].tcpu);

 	}

 	free(tmp);

-- 

2.45.2