From 20699ecf61f21b761fcc369ddc85da5f5cf5a1cf Mon Sep 17 00:00:00 2001
From: Marco Vedovati <marco.vedovati@crowdstrike.com>
Date: Thu, 10 Aug 2023 14:43:53 -0700
Subject: [PATCH] libbpf: Set close-on-exec flag on gzopen

Enable the close-on-exec flag when using gzopen. This is especially important
for multithreaded programs making use of libbpf, where a fork + exec could
race with libbpf library calls, potentially resulting in a file descriptor
leaked to the new process. This got missed in 59842c5451fe ("libbpf: Ensure
libbpf always opens files with O_CLOEXEC").

Fixes: 59842c5451fe ("libbpf: Ensure libbpf always opens files with O_CLOEXEC")
Signed-off-by: Marco Vedovati <marco.vedovati@crowdstrike.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230810214350.106301-1-martin.kelly@crowdstrike.com
---
 src/libbpf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/libbpf.c b/src/libbpf.c
index 17883f5a4..b14a4376a 100644
--- a/src/libbpf.c
+++ b/src/libbpf.c
@@ -1978,9 +1978,9 @@ static int bpf_object__read_kconfig_file(struct bpf_object *obj, void *data)
 		return -ENAMETOOLONG;
 
 	/* gzopen also accepts uncompressed files. */
-	file = gzopen(buf, "r");
+	file = gzopen(buf, "re");
 	if (!file)
-		file = gzopen("/proc/config.gz", "r");
+		file = gzopen("/proc/config.gz", "re");
 
 	if (!file) {
 		pr_warn("failed to open system Kconfig\n");
--
2.33.0