Merged: [compiler] Harden JSCallReducer::ReduceArrayIteratorPrototypeNext
Revision: 65b20a0e65e1078f5dd230a5203e231bec790ab4
BUG=chromium:1234764
NOTRY=true
NOPRESUBMIT=true
NOTREECHECKS=true
R=vahl@chromium.org
Change-Id: I45faf253695011092de144c8e29bafac5337adec
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3084363
Reviewed-by: Lutz Vahl <vahl@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/branch-heads/9.2@{#53}
Cr-Branched-From: 51238348f95a1f5e0acc321efac7942d18a687a2-refs/heads/9.2.230@{#1}
Cr-Branched-From: 587a04f02ab0487d194b55a7137dc2045e071597-refs/heads/master@{#74656}
diff --git a/src/compiler/js-call-reducer.cc b/src/compiler/js-call-reducer.cc
index 99a2971..3e33d06 100644
--- a/src/compiler/js-call-reducer.cc
+++ b/src/compiler/js-call-reducer.cc
@@ -5974,11 +5974,12 @@
Node* etrue = effect;
Node* if_true = graph()->NewNode(common()->IfTrue(), branch);
{
- // We know that the {index} is range of the {length} now.
+ // This extra check exists to refine the type of {index} but also to break
+ // an exploitation technique that abuses typer mismatches.
index = etrue = graph()->NewNode(
- common()->TypeGuard(
- Type::Range(0.0, length_access.type.Max() - 1.0, graph()->zone())),
- index, etrue, if_true);
+ simplified()->CheckBounds(p.feedback(),
+ CheckBoundsFlag::kAbortOnOutOfBounds),
+ index, length, etrue, if_true);
done_true = jsgraph()->FalseConstant();
if (iteration_kind == IterationKind::kKeys) {
