linux-kernel - [PATCH 4.19 095/134] Disable kgdboc failed by echo space to /sys/module/kgdboc/parameters/kgdboc

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 for Android: free password hash cracker in your pocket

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

Message-Id: <20190401170053.130214866@linuxfoundation.org>
Date:   Mon,  1 Apr 2019 19:02:11 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Wentao Wang <witallwang@...il.com>,
        Daniel Thompson <daniel.thompson@...aro.org>
Subject: [PATCH 4.19 095/134] Disable kgdboc failed by echo space to /sys/module/kgdboc/parameters/kgdboc

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Wentao Wang <witallwang@...il.com>

commit 3ec8002951ea173e24b466df1ea98c56b7920e63 upstream.

Echo "" to /sys/module/kgdboc/parameters/kgdboc will fail with "No such
device” error.

This is caused by function "configure_kgdboc" who init err to ENODEV
when the config is empty (legal input) the code go out with ENODEV
returned.

Fixes: 2dd453168643 ("kgdboc: Fix restrict error")
Signed-off-by: Wentao Wang <witallwang@...il.com>
Cc: stable <stable@...r.kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@...aro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/tty/serial/kgdboc.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/tty/serial/kgdboc.c
+++ b/drivers/tty/serial/kgdboc.c
@@ -145,8 +145,10 @@ static int configure_kgdboc(void)
 	char *cptr = config;
 	struct console *cons;
 
-	if (!strlen(config) || isspace(config[0]))
+	if (!strlen(config) || isspace(config[0])) {
+		err = 0;
 		goto noconfig;
+	}
 
 	kgdboc_io_ops.is_console = 0;
 	kgdb_tty_driver = NULL;