Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 351d6204 authored by Qixue Xiao's avatar Qixue Xiao Committed by Greg Kroah-Hartman
Browse files

tty: an overflow of multiplication in drivers/tty/cyclades.c 



there is an overflow in the code :
cyz_polling_cycle = (arg * HZ) / 1000,
the multiplicator arg comes from user, so it may be an overflow if
arg is a big number. And the value of cyc_polling_cycle will be
wrong when it is used next time.

Reported-by: default avatarQixue Xiao <xiaoqixue_1@163.com>
Suggested-by: default avatarYongjian Xu <xuyongjiande@gmail.com>
Suggested-by: default avatarYu Chen <chyyuu@gmail.com>
Signed-off-by: default avatarQixue Xiao <xiaoqixue_1@163.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4903713c

drivers/tty/cyclades.c

+2 −0
Original line number Diff line number Diff line
@@ -2709,6 +2709,8 @@ cy_ioctl(struct tty_struct *tty, 
		break;

#ifndef CONFIG_CYZ_INTR

	case CYZSETPOLLCYCLE:

		if (arg > LONG_MAX / HZ)

			return -ENODEV;

		cyz_polling_cycle = (arg * HZ) / 1000;

		break;

	case CYZGETPOLLCYCLE: