From bc38ef79d8c2e9ff87fac1937c31b0e5b7d740a2 Mon Sep 17 00:00:00 2001 From: Georg Neis Date: Tue, 20 Apr 2021 13:48:07 +0200 Subject: [Backport] CVE-2021-21227: Insufficient data validation in V8 Cherry-pick of patch originally reviewed on https://chromium-review.googlesource.com/c/v8/v8/+/2839559: Merged: [compiler] Fix a bug in VisitSpeculativeIntegerAdditiveOp Revision: 9313c4ce3f32ad81df1c65becccec7e129181ce3 BUG=chromium:1199345 NOTRY=true NOPRESUBMIT=true NOTREECHECKS=true R=nicohartmann@chromium.org Change-Id: I0ee9f13815b1a7d248d4caa506c6930697e1866c Commit-Queue: Georg Neis Reviewed-by: Nico Hartmann Cr-Commit-Position: refs/branch-heads/9.0@{#41} Cr-Branched-From: bd0108b4c88e0d6f2350cb79b5f363fbd02f3eb7-refs/heads/9.0.257@{#1} Cr-Branched-From: 349bcc6a075411f1a7ce2d866c3dfeefc2efa39d-refs/heads/master@{#73001} Reviewed-by: Allan Sandfeld Jensen --- chromium/v8/src/compiler/simplified-lowering.cc | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/chromium/v8/src/compiler/simplified-lowering.cc b/chromium/v8/src/compiler/simplified-lowering.cc index 867a3f9d4a5..e2f34f08796 100644 --- a/chromium/v8/src/compiler/simplified-lowering.cc +++ b/chromium/v8/src/compiler/simplified-lowering.cc @@ -1318,10 +1318,15 @@ class RepresentationSelector { Type right_feedback_type = TypeOf(node->InputAt(1)); // Using Signed32 as restriction type amounts to promising there won't be - // signed overflow. This is incompatible with relying on a Word32 - // truncation in order to skip the overflow check. + // signed overflow. This is incompatible with relying on a Word32 truncation + // in order to skip the overflow check. Similarly, we must not drop -0 from + // the result type unless we deopt for -0 inputs. Type const restriction = - truncation.IsUsedAsWord32() ? Type::Any() : Type::Signed32(); + truncation.IsUsedAsWord32() + ? Type::Any() + : (truncation.identify_zeros() == kIdentifyZeros) + ? Type::Signed32OrMinusZero() + : Type::Signed32(); // Handle the case when no int32 checks on inputs are necessary (but // an overflow check is needed on the output). Note that we do not -- cgit v1.2.1