[02/18] drm: fix unsigned vs signed comparison issue in modeset ctl ioctl.

[Greg KH <gregkh@suse.de>]

2.6.32-longterm review patch.  If anyone has any objections, please let us know.

------------------

From: Dave Airlie <airlied@redhat.com>

commit 1922756124ddd53846877416d92ba4a802bc658f upstream.

This fixes CVE-2011-1013.

Reported-by: Matthiew Herrb (OpenBSD X.org team)
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/gpu/drm/drm_irq.c |    3 ++-
 include/drm/drmP.h        |    2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -540,7 +540,8 @@ int drm_modeset_ctl(struct drm_device *d
 		    struct drm_file *file_priv)
 {
 	struct drm_modeset_ctl *modeset = data;
-	int crtc, ret = 0;
+	int ret = 0;
+	unsigned int crtc;
 
 	/* If drm_vblank_init() hasn't been called yet, just no-op */
 	if (!dev->num_crtcs)
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1016,7 +1016,7 @@ struct drm_device {
 	struct pci_controller *hose;
 #endif
 	struct drm_sg_mem *sg;	/**< Scatter gather memory */
-	int num_crtcs;                  /**< Number of CRTCs on this device */
+	unsigned int num_crtcs;                  /**< Number of CRTCs on this device */
 	void *dev_private;		/**< device private data */
 	void *mm_private;
 	struct address_space *dev_mapping;