From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Mon, 11 Mar 2019 03:15:47 +0000 (-0700)
Subject: 4.4-stable patches
X-Git-Tag: v5.0.2~54
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=35bf82c462a187f5653102ffdfd3f408ba2c3571;p=thirdparty%2Fkernel%2Fstable-queue.git

4.4-stable patches

added patches:
	media-uvcvideo-fix-type-check-leading-to-overflow.patch
---

diff --git a/queue-4.4/media-uvcvideo-fix-type-check-leading-to-overflow.patch b/queue-4.4/media-uvcvideo-fix-type-check-leading-to-overflow.patch
new file mode 100644
index 00000000000..b22748be378
--- /dev/null
+++ b/queue-4.4/media-uvcvideo-fix-type-check-leading-to-overflow.patch
@@ -0,0 +1,62 @@
+From 47bb117911b051bbc90764a8bff96543cbd2005f Mon Sep 17 00:00:00 2001
+From: Alistair Strachan <astrachan@google.com>
+Date: Tue, 18 Dec 2018 20:32:48 -0500
+Subject: media: uvcvideo: Fix 'type' check leading to overflow
+
+From: Alistair Strachan <astrachan@google.com>
+
+commit 47bb117911b051bbc90764a8bff96543cbd2005f upstream.
+
+When initially testing the Camera Terminal Descriptor wTerminalType
+field (buffer[4]), no mask is used. Later in the function, the MSB is
+overloaded to store the descriptor subtype, and so a mask of 0x7fff
+is used to check the type.
+
+If a descriptor is specially crafted to set this overloaded bit in the
+original wTerminalType field, the initial type check will fail (falling
+through, without adjusting the buffer size), but the later type checks
+will pass, assuming the buffer has been made suitably large, causing an
+overflow.
+
+Avoid this problem by checking for the MSB in the wTerminalType field.
+If the bit is set, assume the descriptor is bad, and abort parsing it.
+
+Originally reported here:
+https://groups.google.com/forum/#!topic/syzkaller/Ot1fOE6v1d8
+A similar (non-compiling) patch was provided at that time.
+
+Reported-by: syzbot <syzkaller@googlegroups.com>
+Signed-off-by: Alistair Strachan <astrachan@google.com>
+Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/media/usb/uvc/uvc_driver.c |   14 +++++++++++---
+ 1 file changed, 11 insertions(+), 3 deletions(-)
+
+--- a/drivers/media/usb/uvc/uvc_driver.c
++++ b/drivers/media/usb/uvc/uvc_driver.c
+@@ -1019,11 +1019,19 @@ static int uvc_parse_standard_control(st
+ 			return -EINVAL;
+ 		}
+ 
+-		/* Make sure the terminal type MSB is not null, otherwise it
+-		 * could be confused with a unit.
++		/*
++		 * Reject invalid terminal types that would cause issues:
++		 *
++		 * - The high byte must be non-zero, otherwise it would be
++		 *   confused with a unit.
++		 *
++		 * - Bit 15 must be 0, as we use it internally as a terminal
++		 *   direction flag.
++		 *
++		 * Other unknown types are accepted.
+ 		 */
+ 		type = get_unaligned_le16(&buffer[4]);
+-		if ((type & 0xff00) == 0) {
++		if ((type & 0x7f00) == 0 || (type & 0x8000) != 0) {
+ 			uvc_trace(UVC_TRACE_DESCR, "device %d videocontrol "
+ 				"interface %d INPUT_TERMINAL %d has invalid "
+ 				"type 0x%04x, skipping\n", udev->devnum,