[PATCH 3/3] perf bpf: Fix two memory leakages when calling perf_env__insert_bpf_prog_info()

From: Zhongqiu Han
Date: Thu Nov 28 2024 - 07:56:15 EST


If perf_env__insert_bpf_prog_info() returns false due to a duplicate bpf
prog info node insertion, the temporary info_node and info_linear memory
will leak. Add a check to ensure the memory is freed if the function
returns false.

Fixes: 9c51f8788b5d ("perf env: Avoid recursively taking env->bpf_progs.lock")
Signed-off-by: Zhongqiu Han <quic_zhonhan@xxxxxxxxxxx>
---
tools/perf/util/bpf-event.c | 10 ++++++++--
tools/perf/util/env.c | 7 +++++--
tools/perf/util/env.h | 2 +-
3 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index 13608237c50e..c81444059ad0 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -289,7 +289,10 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
}

info_node->info_linear = info_linear;
- perf_env__insert_bpf_prog_info(env, info_node);
+ if (!perf_env__insert_bpf_prog_info(env, info_node)) {
+ free(info_linear);
+ free(info_node);
+ }
info_linear = NULL;

/*
@@ -480,7 +483,10 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 id)
info_node = malloc(sizeof(struct bpf_prog_info_node));
if (info_node) {
info_node->info_linear = info_linear;
- perf_env__insert_bpf_prog_info(env, info_node);
+ if (!perf_env__insert_bpf_prog_info(env, info_node)) {
+ free(info_linear);
+ free(info_node);
+ }
} else
free(info_linear);

diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index d7865ae5f8f5..38401a289c24 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c
@@ -24,12 +24,15 @@ struct perf_env perf_env;
#include "bpf-utils.h"
#include <bpf/libbpf.h>

-void perf_env__insert_bpf_prog_info(struct perf_env *env,
+bool perf_env__insert_bpf_prog_info(struct perf_env *env,
struct bpf_prog_info_node *info_node)
{
+ bool ret = true;
down_write(&env->bpf_progs.lock);
- __perf_env__insert_bpf_prog_info(env, info_node);
+ if (!__perf_env__insert_bpf_prog_info(env, info_node))
+ ret = false;
up_write(&env->bpf_progs.lock);
+ return ret;
}

bool __perf_env__insert_bpf_prog_info(struct perf_env *env, struct bpf_prog_info_node *info_node)
diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
index 9db2e5a625ed..da11add761d0 100644
--- a/tools/perf/util/env.h
+++ b/tools/perf/util/env.h
@@ -178,7 +178,7 @@ int perf_env__nr_cpus_avail(struct perf_env *env);
void perf_env__init(struct perf_env *env);
bool __perf_env__insert_bpf_prog_info(struct perf_env *env,
struct bpf_prog_info_node *info_node);
-void perf_env__insert_bpf_prog_info(struct perf_env *env,
+bool perf_env__insert_bpf_prog_info(struct perf_env *env,
struct bpf_prog_info_node *info_node);
struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
__u32 prog_id);
--
2.25.1