netdev - [PATCH bpf-next] selftests/bpf: Restore the netns after flow dissector reattach test

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20191017083752.30999-1-jakub@cloudflare.com>
Date:   Thu, 17 Oct 2019 10:37:52 +0200
From:   Jakub Sitnicki <jakub@...udflare.com>
To:     bpf@...r.kernel.org
Cc:     netdev@...r.kernel.org, kernel-team@...udflare.com,
        Alexei Starovoitov <ast@...nel.org>,
        Andrii Nakryiko <andriin@...com>
Subject: [PATCH bpf-next] selftests/bpf: Restore the netns after flow dissector reattach test

flow_dissector_reattach test changes the netns we run in but does not
restore it to the one we started in when finished. This interferes with
tests that run after it. Fix it by restoring the netns when done.

Fixes: f97eea1756f3 ("selftests/bpf: Check that flow dissector can be re-attached")
Reported-by: Alexei Starovoitov <ast@...nel.org>
Reported-by: Andrii Nakryiko <andriin@...com>
Signed-off-by: Jakub Sitnicki <jakub@...udflare.com>
---
 .../bpf/prog_tests/flow_dissector_reattach.c  | 21 +++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/flow_dissector_reattach.c b/tools/testing/selftests/bpf/prog_tests/flow_dissector_reattach.c
index 777faffc4639..1f51ba66b98b 100644
--- a/tools/testing/selftests/bpf/prog_tests/flow_dissector_reattach.c
+++ b/tools/testing/selftests/bpf/prog_tests/flow_dissector_reattach.c
@@ -91,12 +91,18 @@ static void do_flow_dissector_reattach(void)
 
 void test_flow_dissector_reattach(void)
 {
-	int init_net, err;
+	int init_net, self_net, err;
+
+	self_net = open("/proc/self/ns/net", O_RDONLY);
+	if (CHECK_FAIL(self_net < 0)) {
+		perror("open(/proc/self/ns/net");
+		return;
+	}
 
 	init_net = open("/proc/1/ns/net", O_RDONLY);
 	if (CHECK_FAIL(init_net < 0)) {
 		perror("open(/proc/1/ns/net)");
-		return;
+		goto out_close;
 	}
 
 	err = setns(init_net, CLONE_NEWNET);
@@ -108,7 +114,7 @@ void test_flow_dissector_reattach(void)
 	if (is_attached(init_net)) {
 		test__skip();
 		printf("Can't test with flow dissector attached to init_net\n");
-		return;
+		goto out_setns;
 	}
 
 	/* First run tests in root network namespace */
@@ -118,10 +124,17 @@ void test_flow_dissector_reattach(void)
 	err = unshare(CLONE_NEWNET);
 	if (CHECK_FAIL(err)) {
 		perror("unshare(CLONE_NEWNET)");
-		goto out_close;
+		goto out_setns;
 	}
 	do_flow_dissector_reattach();
 
+out_setns:
+	/* Move back to netns we started in. */
+	err = setns(self_net, CLONE_NEWNET);
+	if (CHECK_FAIL(err))
+		perror("setns(/proc/self/ns/net)");
+
 out_close:
 	close(init_net);
+	close(self_net);
 }
-- 
2.20.1