1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
|
// Copyright 2021 The gVisor Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package gohacks
import (
"io/ioutil"
"math/rand"
"os"
"runtime/debug"
"testing"
"golang.org/x/sys/unix"
)
func randBuf(size int) []byte {
b := make([]byte, size)
for i := range b {
b[i] = byte(rand.Intn(256))
}
return b
}
// Size of a page in bytes. Cloned from hostarch.PageSize to avoid a circular
// dependency.
const pageSize = 4096
func testCopy(dst, src []byte) (panicked bool) {
defer func() {
if r := recover(); r != nil {
panicked = true
}
}()
debug.SetPanicOnFault(true)
copy(dst, src)
return panicked
}
func TestSegVOnMemmove(t *testing.T) {
// Test that SIGSEGVs received by runtime.memmove when *not* doing
// CopyIn or CopyOut work gets propagated to the runtime.
const bufLen = pageSize
a, err := unix.Mmap(-1, 0, bufLen, unix.PROT_NONE, unix.MAP_ANON|unix.MAP_PRIVATE)
if err != nil {
t.Fatalf("Mmap failed: %v", err)
}
defer unix.Munmap(a)
b := randBuf(bufLen)
if !testCopy(b, a) {
t.Fatalf("testCopy didn't panic when it should have")
}
if !testCopy(a, b) {
t.Fatalf("testCopy didn't panic when it should have")
}
}
func TestSigbusOnMemmove(t *testing.T) {
// Test that SIGBUS received by runtime.memmove when *not* doing
// CopyIn or CopyOut work gets propagated to the runtime.
const bufLen = pageSize
f, err := ioutil.TempFile("", "sigbus_test")
if err != nil {
t.Fatalf("TempFile failed: %v", err)
}
os.Remove(f.Name())
defer f.Close()
a, err := unix.Mmap(int(f.Fd()), 0, bufLen, unix.PROT_READ|unix.PROT_WRITE, unix.MAP_SHARED)
if err != nil {
t.Fatalf("Mmap failed: %v", err)
}
defer unix.Munmap(a)
b := randBuf(bufLen)
if !testCopy(b, a) {
t.Fatalf("testCopy didn't panic when it should have")
}
if !testCopy(a, b) {
t.Fatalf("testCopy didn't panic when it should have")
}
}
|
