From 9927a403ca8c97798129953fa9cbb5dc259c7cb9 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <error27@gmail.com>
Date: Sat, 19 Jun 2010 15:12:51 +0200
Subject: [PATCH] i915: return -EFAULT if copy_to_user fails

copy_to_user returns the number of bytes remaining to be copied, but we
want to return a negative error code here.  These are returned to
userspace.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
---
 drivers/gpu/drm/i915/i915_dma.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 7796f452ed1d..051c4db7a1d3 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -620,8 +620,10 @@ static int i915_batchbuffer(struct drm_device *dev, void *data,
 		ret = copy_from_user(cliprects, batch->cliprects,
 				     batch->num_cliprects *
 				     sizeof(struct drm_clip_rect));
-		if (ret != 0)
+		if (ret != 0) {
+			ret = -EFAULT;
 			goto fail_free;
+		}
 	}
 
 	mutex_lock(&dev->struct_mutex);
@@ -662,8 +664,10 @@ static int i915_cmdbuffer(struct drm_device *dev, void *data,
 		return -ENOMEM;
 
 	ret = copy_from_user(batch_data, cmdbuf->buf, cmdbuf->sz);
-	if (ret != 0)
+	if (ret != 0) {
+		ret = -EFAULT;
 		goto fail_batch_free;
+	}
 
 	if (cmdbuf->num_cliprects) {
 		cliprects = kcalloc(cmdbuf->num_cliprects,
@@ -676,8 +680,10 @@ static int i915_cmdbuffer(struct drm_device *dev, void *data,
 		ret = copy_from_user(cliprects, cmdbuf->cliprects,
 				     cmdbuf->num_cliprects *
 				     sizeof(struct drm_clip_rect));
-		if (ret != 0)
+		if (ret != 0) {
+			ret = -EFAULT;
 			goto fail_clip_free;
+		}
 	}
 
 	mutex_lock(&dev->struct_mutex);
-- 
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