Patch "drm/vmwgfx: NULL pointer dereference in vmw_surface_define_ioctl()" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    drm/vmwgfx: NULL pointer dereference in vmw_surface_define_ioctl()

to the 4.9-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-vmwgfx-null-pointer-dereference-in-vmw_surface_define_ioctl.patch
and it can be found in the queue-4.9 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 36274ab8c596f1240c606bb514da329add2a1bcd Mon Sep 17 00:00:00 2001
From: Murray McAllister <murray.mcallister@insomniasec.com>
Date: Mon, 27 Mar 2017 11:12:53 +0200
Subject: drm/vmwgfx: NULL pointer dereference in vmw_surface_define_ioctl()

From: Murray McAllister <murray.mcallister@insomniasec.com>

commit 36274ab8c596f1240c606bb514da329add2a1bcd upstream.

Before memory allocations vmw_surface_define_ioctl() checks the
upper-bounds of a user-supplied size, but does not check if the
supplied size is 0.

Add check to avoid NULL pointer dereferences.

Signed-off-by: Murray McAllister <murray.mcallister@insomniasec.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/vmwgfx/vmwgfx_surface.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
@@ -716,8 +716,8 @@ int vmw_surface_define_ioctl(struct drm_
 	for (i = 0; i < DRM_VMW_MAX_SURFACE_FACES; ++i)
 		num_sizes += req->mip_levels[i];
 
-	if (num_sizes > DRM_VMW_MAX_SURFACE_FACES *
-	    DRM_VMW_MAX_MIP_LEVELS)
+	if (num_sizes > DRM_VMW_MAX_SURFACE_FACES * DRM_VMW_MAX_MIP_LEVELS ||
+	    num_sizes == 0)
 		return -EINVAL;
 
 	size = vmw_user_surface_size + 128 +


Patches currently in stable-queue which might be from murray.mcallister@insomniasec.com are

queue-4.9/drm-vmwgfx-avoid-calling-vzalloc-with-a-0-size-in-vmw_get_cap_3d_ioctl.patch
queue-4.9/drm-vmwgfx-null-pointer-dereference-in-vmw_surface_define_ioctl.patch