runtime: function textOff returns incorrect value if multiple text sections are present #35207
Description
What version of Go are you using (go version)?
$ go version go version go1.12.12 linux/ppc64le
Does this issue reproduce with the latest release?
The incorrect code exists in the latest release. The failure will only happen when trying to look up the textOff for an off that is at the end of a text section if there are multiple text sections. Multiple text sections are not common but do happen in Kubernetes and Openshift.
What operating system and processor architecture are you using (go env)?
go env Output
$ go env linux/ppc64le RHEL 7.5
What did you do?
Built and ran the tests for Openshift. By default -race is used for testing.
mkdir -p ~/gocode/src/github.com/openshift
cd ~/gocode/src/github.com/openshift
git clone https://github.com/openshift/origin
cd ~/gocode/src/github.com/openshift/origin
export GOCODE=~/gocode
To run all the tests:
GOTEST_FLAGS='-p 8' TIMEOUT=360s TEST_KUBE=true KUBERNETES_SERVICE_HOST= hack/test-go.sh
To run the test that just fails:
go test -p 8 -race -cover -covermode atomic -timeout 360s github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/registry/core/node/storage
What did you expect to see?
No failures.
What did you see instead?
[boger@moose1 origin]$ go test -p 8 -race -cover -covermode atomic -timeout 360s github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/registry/core/node/storage
unexpected fault address 0xfe1e
fatal error: fault
[signal SIGSEGV: segmentation violation code=0x1 addr=0xfe1e pc=0x3fffb7da84fc]
goroutine 1 [running, locked to thread]:
runtime.throw(0x121b0080, 0x5)
/home/boger/golang/go1.12/go/src/runtime/panic.go:617 +0x5c fp=0xc000596100 sp=0xc0005960c0 pc=0x1003f44c
runtime: unexpected return pc for runtime.sigpanic called from 0x3fffb7da84fc
stack: frame={sp:0xc000596100, fp:0xc000596140} stack=[0xc000578000,0xc000598000)
000000c000596000: 00000000121ae2b3 0000000000000001
000000c000596010: 0000000000000001 0000000000000000
000000c000596020: 0000000010040820 <runtime.printstring+112> 00000000146d6520
000000c000596030: 0000000000000002 000000c0005960f6
000000c000596040: 0000000000000002 00000000121ae2b3
000000c000596050: 0000000000000001 000000001003f608 <runtime.fatalthrow+72>
000000c000596060: 0000000010057f7c <runtime.sigpanic+1036> 0000000000000001
000000c000596070: 0000000010040128 <runtime.printnl+56> 000000001003f44c <runtime.throw+92>
000000c000596080: 000000c0005960f6 0000000000000006
000000c000596090: 00000000121ae2b3 000000c0005960a0
000000c0005960a0: 000000001006e000 <runtime.fatalthrow.func1+0> 000000c000000180
000000c0005960b0: 000000001003f44c <runtime.throw+92> 000000c0005960c0
000000c0005960c0: 0000000010057f9c <runtime.sigpanic+1068> 0000000000000001
000000c0005960d0: 0000000010057f80 <runtime.sigpanic+1040> 0000000010057f84 <runtime.sigpanic+1044>
000000c0005960e0: 000000c0005960e8 000000001006df80 <runtime.throw.func1+0>
000000c0005960f0: 00000000121b0080 0000000000000005
000000c000596100: <00003fffb7da84fc 0000000012671a80
000000c000596110: 0000000011ef39a0 000000001226d068
000000c000596120: 00000000121b0080 0000000000000005
000000c000596130: 0000000010467ba4 <encoding/json.typeFields+6132> 000000000000fe1e
000000c000596140: >00003fffb7db2c54 0000000000000000
000000c000596150: 0000000010467cfc <encoding/json.cachedTypeFields+220> 000000001056a264 <text/template/parse.(*Tree).operand+52>
000000c000596160: 000000c0005967d0 0000000011ef9c40
000000c000596170: 000000c0001df558 0000000011ef39a0
000000c000596180: 000000001226d068 0000000000000002
000000c000596190: 0000000000000002 0000000012671a80
000000c0005961a0: 0000000011ef39a0 000000c000378280
000000c0005961b0: 000000000000000a 0000000000000018
000000c0005961c0: 0000000000000028 000000c000378208
000000c0005961d0: 0000000000000001 0000000000000001
000000c0005961e0: 0000000000000000 0000000010166c00 <regexp/syntax.(*compiler).compile+6640>
000000c0005961f0: 0000000010165730 <regexp/syntax.(*compiler).compile+1312> 0000000012671a80
000000c000596200: 0000000000000025 0000000000000043
000000c000596210: 0000000000000009 0000000000000002
000000c000596220: 0000000000000001 0000000000000003
000000c000596230: 0000000000000007 0000000000000002
runtime.sigpanic()
/home/boger/golang/go1.12/go/src/runtime/signal_unix.go:397 +0x42c fp=0xc000596140 sp=0xc000596100 pc=0x10057f9c
goroutine 19 [chan receive]:
github.com/openshift/origin/vendor/k8s.io/klog.(*loggingT).flushDaemon(0x13d2bb60)
/home/boger/gocode/src/github.com/openshift/origin/vendor/k8s.io/klog/klog.go:1018 +0x90
created by github.com/openshift/origin/vendor/k8s.io/klog.init.0
/home/boger/gocode/src/github.com/openshift/origin/vendor/k8s.io/klog/klog.go:404 +0x84
goroutine 93 [chan receive]:
github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil.(*MergeLogger).outputLoop(0xc000150920)
/home/boger/gocode/src/github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go:174 +0x39c
created by github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil.NewMergeLogger
/home/boger/gocode/src/github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go:92 +0xf8
goroutine 128 [chan receive]:
github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil.(*MergeLogger).outputLoop(0xc000288fa0)
/home/boger/gocode/src/github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go:174 +0x39c
created by github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil.NewMergeLogger
/home/boger/gocode/src/github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go:92 +0xf8
goroutine 126 [chan receive]:
github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil.(*MergeLogger).outputLoop(0xc000288e20)
/home/boger/gocode/src/github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go:174 +0x39c
created by github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil.NewMergeLogger
/home/boger/gocode/src/github.com/openshift/origin/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go:92 +0xf8
FAIL github.com/openshift/origin/vendor/k8s.io/kubernetes/pkg/registry/core/node/storage 0.106s
I have a fix for this. After debugging I found that the problem is in runtime/type.go function textOff where it looks up the text offset from an offset. If the 'off' happens to be the last value in the text section, the wrong value is returned.