[PATCH] perf ftrace: Fix leak in parse_filter_event

From: Michail Tatas

Date: Mon Aug 03 2026 - 03:55:32 EST


strsep() advances the pointer given to it. After the loop s is
either NULL (on success) or points mid buffer (early exit if malloc
fails) so the original buffer is never freed properly.
Fix by adding a tmp pointer for use by strsep and free the original
pointer

Signed-off-by: Michail Tatas <michail.tatas@xxxxxxxxx>
---
tools/perf/builtin-ftrace.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index f7126196b092..4f881a40c311 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -1607,14 +1607,15 @@ static int parse_filter_event(const struct option *opt, const char *str,
{
struct list_head *head = opt->value;
struct filter_entry *entry;
- char *s, *p;
+ char *s, *p, *tmp;
int ret = -ENOMEM;

s = strdup(str);
if (s == NULL)
return -ENOMEM;

- while ((p = strsep(&s, ",")) != NULL) {
+ tmp = s;
+ while ((p = strsep(&tmp, ",")) != NULL) {
entry = malloc(sizeof(*entry) + strlen(p) + 1);
if (entry == NULL)
goto out;
--
2.43.0