diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c b/drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c
index d1e7df500190..5a69606a0593 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c
@@ -324,6 +324,7 @@ void vmw_kms_cursor_snoop(struct vmw_surface *srf,
 	unsigned long kmap_num;
 	SVGA3dCopyBox *box;
 	u32 box_count;
+	u64 src_extent;
 	void *virtual;
 	bool is_iomem;
 	struct vmw_dma_cmd {
@@ -335,6 +336,8 @@ void vmw_kms_cursor_snoop(struct vmw_surface *srf,
 		vmw_surface_get_desc(VMW_CURSOR_SNOOP_FORMAT);
 	const u32 image_pitch = VMW_CURSOR_SNOOP_WIDTH * desc->pitchBytesPerBlock;
 
+	BUILD_BUG_ON(sizeof(*srf->snooper.image) != desc->pitchBytesPerBlock);
+
 	cmd = container_of(header, struct vmw_dma_cmd, header);
 
 	/* No snooper installed, nothing to copy */
@@ -372,8 +375,19 @@ void vmw_kms_cursor_snoop(struct vmw_surface *srf,
 		return;
 	}
 
+	if (box->w == 0 || box->h == 0)
+		return;
+
+	src_extent = (u64)(box->h - 1) * cmd->dma.guest.pitch +
+		     (u64)box->w * desc->pitchBytesPerBlock;
+	if (src_extent > bo->base.size) {
+		DRM_ERROR("Cursor snoop source of %llu bytes exceeds the %zu byte buffer\n",
+			  src_extent, bo->base.size);
+		return;
+	}
+
 	kmap_offset = cmd->dma.guest.ptr.offset >> PAGE_SHIFT;
-	kmap_num = (VMW_CURSOR_SNOOP_HEIGHT * image_pitch) >> PAGE_SHIFT;
+	kmap_num = PFN_UP(src_extent);
 
 	ret = ttm_bo_reserve(bo, true, false, NULL);
 	if (unlikely(ret != 0)) {
@@ -387,14 +401,16 @@ void vmw_kms_cursor_snoop(struct vmw_surface *srf,
 
 	virtual = ttm_kmap_obj_virtual(&map, &is_iomem);
 
-	if (box->w == VMW_CURSOR_SNOOP_WIDTH && cmd->dma.guest.pitch == image_pitch) {
+	if (box->w == VMW_CURSOR_SNOOP_WIDTH &&
+	    box->h == VMW_CURSOR_SNOOP_HEIGHT &&
+	    cmd->dma.guest.pitch == image_pitch) {
 		memcpy(srf->snooper.image, virtual,
 		       VMW_CURSOR_SNOOP_HEIGHT * image_pitch);
 	} else {
-		/* Image is unsigned pointer. */
+		/* The destination stride is in pixels. */
 		for (i = 0; i < box->h; i++)
-			memcpy(srf->snooper.image + i * image_pitch,
-			       virtual + i * cmd->dma.guest.pitch,
+			memcpy(srf->snooper.image + i * VMW_CURSOR_SNOOP_WIDTH,
+			       virtual + (size_t)i * cmd->dma.guest.pitch,
 			       box->w * desc->pitchBytesPerBlock);
 	}
 	srf->snooper.id++;