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
|
/* Force .got aligned to 4K, so it very likely gets at 0x804a100
(0x60 bytes .tdata and 0xa0 bytes .dynamic) */
.section ".tdata", "awT", @progbits
.balign 4096
.globl sg1, sg2, sg3, sg4, sg5, sg6, sg7, sg8
.globl sh1, sh2, sh3, sh4, sh5, sh6, sh7, sh8
.hidden sh1, sh2, sh3, sh4, sh5, sh6, sh7, sh8
sg1: .long 17
sg2: .long 18
sg3: .long 19
sg4: .long 20
sg5: .long 21
sg6: .long 22
sg7: .long 23
sg8: .long 24
sl1: .long 65
sl2: .long 66
sl3: .long 67
sl4: .long 68
sl5: .long 69
sl6: .long 70
sl7: .long 71
sl8: .long 72
sh1: .long 257
sh2: .long 258
sh3: .long 259
sh4: .long 260
sh5: .long 261
sh6: .long 262
sh7: .long 263
sh8: .long 264
/* Force .text aligned to 4K, so it very likely gets at 0x8049000. */
.text
.balign 4096
.globl fn2
.type fn2,@function
fn2:
pushl %ebp
movl %esp, %ebp
pushl %ebx
pushl %eax
call 1f
1: popl %ebx
addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ebx
nop;nop;nop;nop
/* GD -> IE because variable is not defined in executable */
leal sG1@tlsgd(,%ebx,1), %eax
call ___tls_get_addr@plt
nop;nop;nop;nop
/* GD -> IE because variable is not defined in executable where
the variable is referenced through @gottpoff too */
leal sG2@tlsgd(,%ebx,1), %eax
call ___tls_get_addr@plt
nop;nop;nop;nop
/* GD -> IE because variable is not defined in executable where
the variable is referenced through @gotntpoff too */
leal sG3@tlsgd(,%ebx,1), %eax
call ___tls_get_addr@plt
nop;nop;nop;nop
/* GD -> IE because variable is not defined in executable where
the variable is referenced through @gottpoff and @gotntpoff too */
leal sG4@tlsgd(,%ebx,1), %eax
call ___tls_get_addr@plt
nop;nop;nop;nop
/* GD -> LE with global variable defined in executable */
leal sg1@tlsgd(,%ebx,1), %eax
call ___tls_get_addr@plt
nop;nop;nop;nop
/* GD -> LE with local variable defined in executable */
leal sl1@tlsgd(,%ebx,1), %eax
call ___tls_get_addr@plt
nop;nop;nop;nop
/* GD -> LE with hidden variable defined in executable */
leal sh1@tlsgd(,%ebx,1), %eax
call ___tls_get_addr@plt
nop;nop;nop;nop
/* LD -> LE */
leal sl1@tlsldm(%ebx), %eax
call ___tls_get_addr@PLT
nop;nop
leal sl1@dtpoff(%eax), %edx
nop;nop
leal sl2@dtpoff(%eax), %ecx
nop;nop;nop;nop
/* LD -> LE against hidden variables */
leal sh1@tlsldm(%ebx), %eax
call ___tls_get_addr@PLT
nop;nop
leal sh1@dtpoff(%eax), %edx
nop;nop
leal sh2@dtpoff(%eax), %ecx
nop;nop;nop;nop
/* @gottpoff IE against global var */
movl %gs:0, %ecx
nop;nop
subl sG2@gottpoff(%ebx), %ecx
nop;nop;nop;nop
/* @gottpoff IE against global var */
movl %gs:0, %eax
nop;nop
subl sG4@gottpoff(%ebx), %eax
nop;nop;nop;nop
/* @gotntpoff IE against global var */
movl %gs:0, %ecx
nop;nop
addl sG3@gotntpoff(%ebx), %ecx
nop;nop;nop;nop
/* @gotntpoff IE against global var */
movl %gs:0, %eax
nop;nop
addl sG4@gotntpoff(%ebx), %eax
nop;nop;nop;nop
/* @gottpoff IE -> LE against global var defined in exec */
movl %gs:0, %ecx
nop;nop
subl sg1@gottpoff(%ebx), %ecx
nop;nop;nop;nop
/* @gotntpoff IE -> LE against local var */
movl %gs:0, %ecx
nop;nop
addl sl1@gotntpoff(%ebx), %eax
nop;nop;nop;nop
/* @gottpoff IE -> LE against hidden var */
movl %gs:0, %ecx
nop;nop
subl sh1@gottpoff(%ebx), %ecx
nop;nop;nop;nop
/* Direct access through %gs */
/* @gotntpoff IE against global var */
movl sG5@gotntpoff(%ebx), %ecx
nop;nop
movl %gs:(%ecx), %edx
nop;nop;nop;nop
/* @gotntpoff IE->LE against local var */
movl sl5@gotntpoff(%ebx), %eax
nop;nop
movl %gs:(%eax), %edx
nop;nop;nop;nop
/* @gotntpoff IE->LE against hidden var */
movl sh5@gotntpoff(%ebx), %edx
nop;nop
movl %gs:(%edx), %edx
nop;nop;nop;nop
/* GD -> IE because variable is not defined in executable */
leal sG1@tlsgd(%ebx), %eax
call ___tls_get_addr@plt
nop;nop;nop;nop;nop
movl -4(%ebp), %ebx
leave
ret
|