Commit 43995f0f authored by Tetsuo Handa's avatar Tetsuo Handa Committed by openeuler-sync-bot
Browse files

Input: MT - limit max slots 

stable inclusion
from stable-v6.6.48
commit 8f04edd554d191834e9e1349ef030318ea6b11ba
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAOXZN
CVE: CVE-2024-45008

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8f04edd554d191834e9e1349ef030318ea6b11ba



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

commit 99d3bf5f7377d42f8be60a6b9cb60fb0be34dceb upstream.

syzbot is reporting too large allocation at input_mt_init_slots(), for
num_slots is supplied from userspace using ioctl(UI_DEV_CREATE).

Since nobody knows possible max slots, this patch chose 1024.

Reported-by: default avatarsyzbot <syzbot+0122fa359a69694395d5@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=0122fa359a69694395d5


Suggested-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Cc: George Kennedy <george.kennedy@oracle.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarYuan Can <yuancan@huawei.com>
(cherry picked from commit 9ae81b11)
parent ef5e9d04

drivers/input/input-mt.c

+3 −0
Original line number Diff line number Diff line
@@ -45,6 +45,9 @@ int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots, 
		return 0;

	if (mt)

		return mt->num_slots != num_slots ? -EINVAL : 0;

	/* Arbitrary limit for avoiding too large memory allocation. */

	if (num_slots > 1024)

		return -EINVAL;



	mt = kzalloc(struct_size(mt, slots, num_slots), GFP_KERNEL);

	if (!mt)