[PATCH 5.18 062/879] selftests/bpf: Fix file descriptor leak in load_kallsyms()

From: Greg Kroah-Hartman
Date: Tue Jun 07 2022 - 18:02:29 EST


From: Yuntao Wang <ytcoode@xxxxxxxxx>

[ Upstream commit 2d0df01974ce2b59b6f7d5bd3ea58d74f12ddf85 ]

Currently, if sym_cnt > 0, it just returns and does not close file, fix it.

Signed-off-by: Yuntao Wang <ytcoode@xxxxxxxxx>
Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Link: https://lore.kernel.org/bpf/20220405145711.49543-1-ytcoode@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/testing/selftests/bpf/trace_helpers.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c
index 3d6217e3aff7..9c4be2cdb21a 100644
--- a/tools/testing/selftests/bpf/trace_helpers.c
+++ b/tools/testing/selftests/bpf/trace_helpers.c
@@ -25,15 +25,12 @@ static int ksym_cmp(const void *p1, const void *p2)

int load_kallsyms(void)
{
- FILE *f = fopen("/proc/kallsyms", "r");
+ FILE *f;
char func[256], buf[256];
char symbol;
void *addr;
int i = 0;

- if (!f)
- return -ENOENT;
-
/*
* This is called/used from multiplace places,
* load symbols just once.
@@ -41,6 +38,10 @@ int load_kallsyms(void)
if (sym_cnt)
return 0;

+ f = fopen("/proc/kallsyms", "r");
+ if (!f)
+ return -ENOENT;
+
while (fgets(buf, sizeof(buf), f)) {
if (sscanf(buf, "%p %c %s", &addr, &symbol, func) != 3)
break;
--
2.35.1