[PATCH xserver] glamor: Cannot use copies when accessing outside of composite source

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

Commit b64108fa ("glamor: Check for composite operations which are
equivalent to copies") failed to copy conditions from exaComposite which
ensure that the composite operation doesn't access outside of the source
picture.

This fixes rendercheck regressions from the commit above.

Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---

Apologies for jumping the gun on the previous patch by submitting it
without appropriate testing with rendercheck.

There is one regression left with this patch (blend test on a8), that
one is fixed by https://patchwork.freedesktop.org/patch/87222/ .

 glamor/glamor_render.c | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/glamor/glamor_render.c b/glamor/glamor_render.c
index 9c5cca6..f1bfe03 100644
--- a/glamor/glamor_render.c
+++ b/glamor/glamor_render.c
@@ -1424,18 +1424,21 @@ glamor_composite_clipped_region(CARD8 op,
     if (!mask && !source->alphaMap && !dest->alphaMap
         && source->pDrawable && !source->transform
         && ((op == PictOpSrc
-             && ((source->format == dest->format
-                  || (PICT_FORMAT_COLOR(dest->format)
-                      && PICT_FORMAT_COLOR(source->format)
-                      && dest->format == PICT_FORMAT(PICT_FORMAT_BPP(source->format),
-                                                     PICT_FORMAT_TYPE(source->format),
-                                                     0,
-                                                     PICT_FORMAT_R(source->format),
-                                                     PICT_FORMAT_G(source->format),
-                                                     PICT_FORMAT_B(source->format))))
-                 || (op == PictOpOver
-                     && source->format == dest->format
-                     && !PICT_FORMAT_A(source->format)))))) {
+             && (source->format == dest->format
+                 || (PICT_FORMAT_COLOR(dest->format)
+                     && PICT_FORMAT_COLOR(source->format)
+                     && dest->format == PICT_FORMAT(PICT_FORMAT_BPP(source->format),
+                                                    PICT_FORMAT_TYPE(source->format),
+                                                    0,
+                                                    PICT_FORMAT_R(source->format),
+                                                    PICT_FORMAT_G(source->format),
+                                                    PICT_FORMAT_B(source->format)))))
+            || (op == PictOpOver
+                && source->format == dest->format
+                && !PICT_FORMAT_A(source->format)))
+        && x_source >= 0 && y_source >= 0
+        && (x_source + width) <= source->pDrawable->width
+        && (y_source + height) <= source->pDrawable->height) {
         glamor_copy(source->pDrawable, dest->pDrawable, NULL,
                     box, nbox, x_source - x_dest,
                     y_source - y_dest, FALSE, FALSE, 0, NULL);
-- 
2.8.1