From ea72fbf588ac9c017224dcdaa2019ff52ca56fee Mon Sep 17 00:00:00 2001
From: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Date: Wed, 11 Apr 2018 11:47:32 -0400
Subject: [PATCH] media: v4l2-compat-ioctl32: prevent go past max size
Git-commit: ea72fbf588ac9c017224dcdaa2019ff52ca56fee
Patch-mainline: v4.18-rc1
References: bsc#1051510
As warned by smatch:
drivers/media/v4l2-core/v4l2-compat-ioctl32.c:879 put_v4l2_ext_controls32() warn: check for integer overflow 'count'
The access_ok() logic should check for too big arrays too.
Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index 4312935f1dfc..d03a44d89649 100644
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -871,7 +871,7 @@ static int put_v4l2_ext_controls32(struct file *file,
get_user(kcontrols, &kp->controls))
return -EFAULT;
- if (!count)
+ if (!count || count > (U32_MAX/sizeof(*ucontrols)))
return 0;
if (get_user(p, &up->controls))
return -EFAULT;
--
2.18.0