From: Young_X <YangX92@hotmail.com>
Date: Wed, 3 Oct 2018 12:54:29 +0000 (+0000)
Subject: cdrom: fix improper type cast, which can leat to information leak.
X-Git-Tag: v4.1.12-124.31.3~420
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=7c2093cdf2e2782be98c01514e1d7cf20c254a8e;p=users%2Fjedix%2Flinux-maple.git

cdrom: fix improper type cast, which can leat to information leak.

There is another cast from unsigned long to int which causes
a bounds check to fail with specially crafted input. The value is
then used as an index in the slot array in cdrom_slot_status().

This issue is similar to CVE-2018-16658 and CVE-2018-10940.

Signed-off-by: Young_X <YangX92@hotmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
(cherry picked from commit e4f3aa2e1e67bb48dfbaaf1cad59013d5a5bc276)

Orabug: 28929767
CVE: CVE-2018-18710

Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Allen Pais <allen.pais@oracle.com>
Signed-off-by: Brian Maly <brian.maly@oracle.com>
---

diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index 39e65eb3dcf0..2411edf92fe5 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -2427,7 +2427,7 @@ static int cdrom_ioctl_select_disc(struct cdrom_device_info *cdi,
 		return -ENOSYS;
 
 	if (arg != CDSL_CURRENT && arg != CDSL_NONE) {
-		if ((int)arg >= cdi->capacity)
+		if (arg >= cdi->capacity)
 			return -EINVAL;
 	}