crypto/ecdsa: signature verification succeeds when it should fail #42340
Description
What version of Go are you using (go version)?
go version devel +b53df56 Fri Oct 30 19:00:33 2020 +0000 linux/amd64
Does this issue reproduce with the latest release?
I think so.
What operating system and processor architecture are you using (go env)?
GO111MODULE="off"
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/jhg/.cache/go-build"
GOENV="/home/jhg/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/mnt/2tb/golang/go/packages/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/mnt/2tb/golang/go/packages"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/mnt/2tb/golang/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/mnt/2tb/golang/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build057338421=/tmp/go-build -gno-record-gcc-switches"
What did you do?
https://play.golang.org/p/cpkYx0J-eh5
What did you expect to see?
Console output:
false
What did you see instead?
Console output:
true
Notes
Found with fuzzing, hence the odd values.