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
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
|
mem='\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f'+
'\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff'+
'\x00'.repeat(65488) +
'\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff'
let accessWidth = {
'8_s': 1,
'8_u': 1,
'16_s': 2,
'16_u': 2,
'': 4,
'f32': 4,
'f64': 8,
}
let baseOp = {
'8_s': 'i32',
'8_u': 'i32',
'16_s': 'i32',
'16_u': 'i32',
'': 'i32',
'f32': 'f32',
'f64': 'f64',
}
function toSigned(width, num) {
let unsignedMax = Math.pow(2, accessWidth[width] * 8) - 1;
let signedMax = Math.pow(2, accessWidth[width] * 8 - 1) - 1;
return (num <= signedMax ? num : -(unsignedMax + 1 - num));
}
function fromLittleEndianNum(width, bytes) {
let base = 1;
var res = 0;
for (var i = 0; i < accessWidth[width]; i++) {
res += base * bytes[i];
base *= 256;
}
return res;
}
function getInt(width, offset, mem) {
var bytes = [ ];
for (var i = offset; i < offset + accessWidth[width]; i++) {
if (i < mem.length)
bytes.push(mem.charCodeAt(i));
else
bytes.push(0);
}
var res = fromLittleEndianNum(width, bytes);
if (width == '8_s' || width == '16_s' || width == '')
res = toSigned(width, res);
return res;
}
function loadTwiceModule(type, ext, offset, align) {
// TODO: Generate memory from byte string
return wasmEvalText(
`(module
(memory 1)
(data (i32.const 0) "\\00\\01\\02\\03\\04\\05\\06\\07\\08\\09\\0a\\0b\\0c\\0d\\0e\\0f")
(data (i32.const 16) "\\f0\\f1\\f2\\f3\\f4\\f5\\f6\\f7\\f8\\f9\\fa\\fb\\fc\\fd\\fe\\ff")
(data (i32.const 65520) "\\f0\\f1\\f2\\f3\\f4\\f5\\f6\\f7\\f8\\f9\\fa\\fb\\fc\\fd\\fe\\ff")
(func (param i32) (param i32) (result ${type})
(drop (${type}.load${ext}
offset=${offset}
${align != 0 ? 'align=' + align : ''}
(local.get 0)
))
(${type}.load${ext}
offset=${offset}
${align != 0 ? 'align=' + align : ''}
(local.get 1)
)
) (export "" (func 0)))`
).exports[""];
}
function loadTwiceSameBasePlusConstModule(type, ext, offset, align, addConst) {
return wasmEvalText(
`(module
(memory 1)
(data (i32.const 0) "\\00\\01\\02\\03\\04\\05\\06\\07\\08\\09\\0a\\0b\\0c\\0d\\0e\\0f")
(data (i32.const 16) "\\f0\\f1\\f2\\f3\\f4\\f5\\f6\\f7\\f8\\f9\\fa\\fb\\fc\\fd\\fe\\ff")
(data (i32.const 65520) "\\f0\\f1\\f2\\f3\\f4\\f5\\f6\\f7\\f8\\f9\\fa\\fb\\fc\\fd\\fe\\ff")
(func (param i32) (result ${type})
(drop (${type}.load${ext}
offset=${offset}
${align != 0 ? 'align=' + align : ''}
(local.get 0)
))
(${type}.load${ext}
offset=${offset}
${align != 0 ? 'align=' + align : ''}
(i32.add (local.get 0) (i32.const ${addConst}))
)
) (export "" (func 0)))`
).exports[""];
}
function loadTwiceSameBasePlusNonConstModule(type, ext, offset, align) {
return wasmEvalText(
`(module
(memory 1)
(data (i32.const 0) "\\00\\01\\02\\03\\04\\05\\06\\07\\08\\09\\0a\\0b\\0c\\0d\\0e\\0f")
(data (i32.const 16) "\\f0\\f1\\f2\\f3\\f4\\f5\\f6\\f7\\f8\\f9\\fa\\fb\\fc\\fd\\fe\\ff")
(data (i32.const 65520) "\\f0\\f1\\f2\\f3\\f4\\f5\\f6\\f7\\f8\\f9\\fa\\fb\\fc\\fd\\fe\\ff")
(func (param i32) (param i32) (result ${type})
(drop (${type}.load${ext}
offset=${offset}
${align != 0 ? 'align=' + align : ''}
(local.get 0)
))
(${type}.load${ext}
offset=${offset}
${align != 0 ? 'align=' + align : ''}
(i32.add (local.get 0) (local.get 1))
)
) (export "" (func 0)))`
).exports[""];
}
/*
* On x64 falsely removed bounds checks will be masked by the signal handlers.
* Thus it is important that these tests be run on x86.
*/
function testOOB(mod, args) {
assertErrorMessage(() => mod(...args), WebAssembly.RuntimeError, /index out of bounds/);
}
function testOk(mod, args, expected, expectedType) {
assertEq(mod(...args), expected);
}
// TODO: It would be nice to verify how many BCs are eliminated on positive tests.
const align = 0;
for (let offset of [0, 1, 2, 3, 4, 8, 16, 41, 0xfff8]) {
var widths = ['8_s', '8_u', '16_s', '16_u', '']
for (let width of widths) {
// Accesses of 1 byte.
let lastValidIndex = 0x10000 - offset - accessWidth[width];
let op = baseOp[width];
var mod = loadTwiceModule(op, width, offset, align);
// Two consecutive loads from two different bases
testOk(mod, [lastValidIndex, lastValidIndex], getInt(width, lastValidIndex + offset, mem), op);
testOOB(mod, [lastValidIndex + 42, lastValidIndex + 42]);
testOOB(mod, [lastValidIndex, lastValidIndex + 42]);
mod = loadTwiceSameBasePlusConstModule(op, width, offset, align, 1);
testOk(mod, [lastValidIndex-1], getInt(width, lastValidIndex + offset, mem), op);
testOOB(mod, [lastValidIndex]);
// Two consecutive loads from same base with different offsets
mod = loadTwiceSameBasePlusConstModule(op, width, offset, align, 2);
testOk(mod, [lastValidIndex-2], getInt(width, lastValidIndex + offset, mem), op);
testOOB(mod, [lastValidIndex-1, 2]);
mod = loadTwiceSameBasePlusConstModule(op, width, offset, align, lastValidIndex);
testOk(mod, [0], getInt(width, lastValidIndex + offset, mem), op);
testOOB(mod, [1]);
mod = loadTwiceSameBasePlusNonConstModule(op, width, offset, align);
testOk(mod, [0, 1], getInt(width, 1 + offset, mem), op);
testOk(mod, [0, lastValidIndex], getInt(width, lastValidIndex + offset, mem), op);
testOOB(mod, [1, lastValidIndex])
// TODO: All of the above with mixed loads and stores
// TODO: Branching - what do we want?
// TODO: Just loops
// - loop invariant checks
// - loop dependant checks remaining inbounds
// - loop dependant checks going out-of bounds.
//
// TODO: Loops + branching
// - loop invariant checks guarded by a loop invariant branch?
}
}
|
