From 53bbfa689670d00ce5fa12b90fcde9526bc649ca Mon Sep 17 00:00:00 2001
From: Nicolas Bouchinet <nicolas.bouchinet@ssi.gouv.fr>
Date: Tue, 12 Nov 2024 14:13:31 +0100
Subject: [PATCH] tty: ldsic: fix tty_ldisc_autoload sysctl's proc_handler

commit 635a9fca54f4f4148be1ae1c7c6bd37af80f5773 upstream.

Commit 7c0cca7c847e ("tty: ldisc: add sysctl to prevent autoloading of
ldiscs") introduces the tty_ldisc_autoload sysctl with the wrong
proc_handler. .extra1 and .extra2 parameters are set to avoid other values
thant SYSCTL_ZERO or SYSCTL_ONE to be set but proc_dointvec do not uses
them.

This commit fixes this by using proc_dointvec_minmax instead of
proc_dointvec.

Fixes: 7c0cca7c847e ("tty: ldisc: add sysctl to prevent autoloading of ldiscs")
Cc: stable <stable@kernel.org>
Signed-off-by: Nicolas Bouchinet <nicolas.bouchinet@ssi.gouv.fr>
Reviewed-by: Lin Feng <linf@wangsu.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241112131357.49582-4-nicolas.bouchinet@clip-os.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/tty/tty_io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 9771072da177c..dcb1769c3625c 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -3631,7 +3631,7 @@ static struct ctl_table tty_table[] = {
 		.data		= &tty_ldisc_autoload,
 		.maxlen		= sizeof(tty_ldisc_autoload),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
+		.proc_handler	= proc_dointvec_minmax,
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-- 
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