linux-kernel - [PATCH v2 10/15] selftests/nolibc: fix up failures when CONFIG_PROC

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

Message-Id: <dc306c108c6bb83dc4dde6b973c0e41c81b3da98.1688078605.git.falcon@tinylab.org>
Date:   Fri, 30 Jun 2023 07:49:42 +0800
From:   Zhangjin Wu <falcon@...ylab.org>
To:     thomas@...ch.de, w@....eu
Cc:     falcon@...ylab.org, arnd@...db.de, linux-kernel@...r.kernel.org,
        linux-kselftest@...r.kernel.org
Subject: [PATCH v2 10/15] selftests/nolibc: fix up failures when CONFIG_PROC_FS=n

For CONFIG_PROC_FS=n, the /proc is not mountable, but the /proc
directory has been created in the prepare() stage whenever /proc is
there or not.

so, the checking of /proc in the run_syscall() stage will be always true
and at last it will fail all of the procfs dependent test cases, which
deviates from the 'cond' check design of the EXPECT_xx macros, without
procfs, these test cases should be skipped instead of failed.

To solve this issue, one method is checking /proc/self instead of /proc,
another method is removing the /proc directory completely for
CONFIG_PROC_FS=n, we apply the second method to avoid misleading the
users.

Signed-off-by: Zhangjin Wu <falcon@...ylab.org>
---
 tools/testing/selftests/nolibc/nolibc-test.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 2725d3dbfaf0..c0f5302ada5d 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -1047,8 +1047,11 @@ int prepare(void)

 	/* try to mount /proc if not mounted. Silently fail otherwise */
 	if (stat("/proc/.", &stat_buf) == 0 || mkdir("/proc", 0755) == 0) {
-		if (stat("/proc/self", &stat_buf) != 0)
-			mount("/proc", "/proc", "proc", 0, 0);
+		if (stat("/proc/self", &stat_buf) != 0) {
+			/* If not mountable, remove /proc completely to avoid misuse */
+			if (mount("none", "/proc", "proc", 0, 0) != 0)
+				rmdir("/proc");
+		}
 	}

 	return 0;
-- 
2.25.1