From: Alyssa Milburn <amilburn@zall.org>
Date: Sat, 1 Apr 2017 17:34:08 +0000 (-0300)
Subject: [media] zr364xx: enforce minimum size when reading header
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=ee0fe833d96793853335844b6d99fb76bd12cbeb;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

[media] zr364xx: enforce minimum size when reading header

This code copies actual_length-128 bytes from the header, which will
underflow if the received buffer is too small.

Signed-off-by: Alyssa Milburn <amilburn@zall.org>
Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
---

diff --git a/drivers/media/usb/zr364xx/zr364xx.c b/drivers/media/usb/zr364xx/zr364xx.c
index f2d6fc03dda0..efdcd5bd6a4c 100644
--- a/drivers/media/usb/zr364xx/zr364xx.c
+++ b/drivers/media/usb/zr364xx/zr364xx.c
@@ -600,6 +600,14 @@ static int zr364xx_read_video_callback(struct zr364xx_camera *cam,
 	ptr = pdest = frm->lpvbits;
 
 	if (frm->ulState == ZR364XX_READ_IDLE) {
+		if (purb->actual_length < 128) {
+			/* header incomplete */
+			dev_info(&cam->udev->dev,
+				 "%s: buffer (%d bytes) too small to hold jpeg header. Discarding.\n",
+				 __func__, purb->actual_length);
+			return -EINVAL;
+		}
+
 		frm->ulState = ZR364XX_READ_FRAME;
 		frm->cur_size = 0;