From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Tue, 3 Jul 2018 15:30:16 +0300
Subject: drm/i810: off by one in i810_dma_vertex()
Git-commit: a1de8d0a7e2cc79dad6d469901b3b5d4c94c4554
Patch-mainline: v4.19-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

If vertex->idx == dma->buf_count then we end up reading one element
beyond the end of the dma->buflist[] array.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180703123015.kma7v7rwtdy4urce@kili.mountain

Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/i810/i810_dma.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/i810/i810_dma.c
+++ b/drivers/gpu/drm/i810/i810_dma.c
@@ -934,7 +934,7 @@ static int i810_dma_vertex(struct drm_de
 	DRM_DEBUG("idx %d used %d discard %d\n",
 		  vertex->idx, vertex->used, vertex->discard);
 
-	if (vertex->idx < 0 || vertex->idx > dma->buf_count)
+	if (vertex->idx < 0 || vertex->idx >= dma->buf_count)
 		return -EINVAL;
 
 	i810_dma_dispatch_vertex(dev,