Patch "drm: add a check for x/y in drm_mode_setcrtc" has been added to the 3.10-stable tree

Patch "drm: add a check for x/y in drm_mode_setcrtc" has been added to the 3.10-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    drm: add a check for x/y in drm_mode_setcrtc

to the 3.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-add-a-check-for-x-y-in-drm_mode_setcrtc.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 01447e9f04ba1c49a9534ae6a5a6f26c2bb05226 Mon Sep 17 00:00:00 2001
From: Zhao Junwang <zhjwpku@gmail.com>
Date: Tue, 7 Jul 2015 17:08:35 +0800
Subject: drm: add a check for x/y in drm_mode_setcrtc

From: Zhao Junwang <zhjwpku@gmail.com>

commit 01447e9f04ba1c49a9534ae6a5a6f26c2bb05226 upstream.

legacy setcrtc ioctl does take a 32 bit value which might indeed
overflow

the checks of crtc_req->x > INT_MAX and crtc_req->y > INT_MAX aren't
needed any more with this

v2: -polish the annotation according to Daniel's comment

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Zhao Junwang <zhjwpku@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/drm_crtc.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1955,8 +1955,11 @@ int drm_mode_setcrtc(struct drm_device *
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
 		return -EINVAL;
 
-	/* For some reason crtc x/y offsets are signed internally. */
-	if (crtc_req->x > INT_MAX || crtc_req->y > INT_MAX)
+	/*
+	 * Universal plane src offsets are only 16.16, prevent havoc for
+	 * drivers using universal plane code internally.
+	 */
+	if (crtc_req->x & 0xffff0000 || crtc_req->y & 0xffff0000)
 		return -ERANGE;
 
 	drm_modeset_lock_all(dev);


Patches currently in stable-queue which might be from zhjwpku@gmail.com are

queue-3.10/drm-add-a-check-for-x-y-in-drm_mode_setcrtc.patch