From: Ben Skeggs <bskeggs@redhat.com>
Date: Tue, 13 Sep 2011 20:08:06 +0000 (+1000)
Subject: drm/ttm: request zeroed system memory pages for new TT buffer objects
X-Git-Tag: v3.0.13~71
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=8215014c1d9d78ef14260a46ee2a136acc3d283a;p=karo-tx-linux.git

drm/ttm: request zeroed system memory pages for new TT buffer objects

commit ff02b13f6867af72682d7a9bb9bd705f9af2bab0 upstream.

Fixes an information leak to userspace, we were handing out un-zeroed pages
for any newly created TTM_PL_TT buffer.

Reported-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Tested-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index e2b2d7866877..81b68508dc13 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -394,7 +394,8 @@ static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
 
 	if (!(new_man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
 		if (bo->ttm == NULL) {
-			ret = ttm_bo_add_ttm(bo, false);
+			bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED);
+			ret = ttm_bo_add_ttm(bo, zero);
 			if (ret)
 				goto out_err;
 		}