1 /* PR middle-end/91631 - buffer overflow into an array member of a declared
2 object not detected
3 Test to verify that past-the-end accesses by string functions to member
4 arrays by-reference objects are diagnosed.
5 { dg-do compile }
6 { dg-options "-O2 -Wall -Wno-unused-local-typedefs -Wno-stringop-overflow -ftrack-macro-expansion=0" }
7 { dg-require-effective-target alloca } */
8
9 #define SA(expr) typedef int StaticAssert [2 * !!(expr) - 1]
10
11 typedef __SIZE_TYPE__ size_t;
12
13 extern char* strcpy (char*, const char*);
14 extern char* strncpy (char*, const char*, size_t);
15
16 void sink (void*);
17
18 struct MA17
19 {
20 char pad[4];
21 char a1[1], a2[2], a3[3], a4[4], a5[5], a6[6], a7[7], a8[8], a9[9], a10[10];
22 char a11[11], a12[12], a13[13], a14[14], a15[15], a16[16], a17[17], ax[];
23 };
24
25 extern struct MA17 gma;
26 extern struct MA17 gma2[2];
27
28 struct MA17 igma_3 = { .ax = { 1, 2, 3 } };
29 struct MA17 igma2_[2];
30
31 #define S36 "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
32
33 #define S(N) (S36 + sizeof (S36) - N - 1)
34
35 /* In the test macro, prevent the strcpy to memcpy transformation
36 by using a local array initialized with the string literal. Without
37 it, GCC transforms the strcpy call with memcpy which (unfortunately)
38 permits accesses that cross subobject boundaries. */
39 #define T(dst, n) \
40 do { \
41 const char a[] = S36; \
42 strcpy (dst, a + sizeof a - n - 1); \
43 sink (dst); \
44 } while (0)
45
46 void strcpy_global (void)
47 {
48 T (gma.a1, 0);
49 T (gma.a1, 1); // { dg-warning "'strcpy' offset 5 from the object at 'gma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 4" }
50 T (gma.a1, 4); // { dg-warning "'strcpy' offset \\\[5, 8] from the object at 'gma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 4" }
51
52 T (gma.a2, 1);
53 T (gma.a2, 2); // { dg-warning "'strcpy' offset 7 from the object at 'gma' is out of the bounds of referenced subobject 'a2' with type 'char\\\[2]' at offset 5" }
54
55 T (gma.a3, 2);
56 T (gma.a3, 3); // { dg-warning "'strcpy' offset 10 from the object at 'gma' is out of the bounds of referenced subobject 'a3' with type 'char\\\[3]' at offset 7" }
57
58 T (gma.a4, 3);
59 T (gma.a4, 4); // { dg-warning "'strcpy' offset 14 from the object at 'gma' is out of the bounds of referenced subobject 'a4' with type 'char\\\[4]' at offset 10" }
60
61 T (gma.a5, 4);
62 T (gma.a5, 5); // { dg-warning "'strcpy' offset 19 from the object at 'gma' is out of the bounds of referenced subobject 'a5' with type 'char\\\[5]' at offset 14" }
63
64 SA (__builtin_offsetof (struct MA17, a17) == 140);
65
66 T (gma.a17, 16);
67 T (gma.a17, 17); // { dg-warning "'strcpy' offset 157 from the object at 'gma' is out of the bounds of referenced subobject 'a17' with type 'char\\\[17]' at offset 140" }
68
69 SA (__builtin_offsetof (struct MA17, ax) == 157);
70 // GCC allows static initialization of flexible array members of
71 // non-local objects. Verify that writing into one that may be
72 // initialized in another translation unit isn't diagnosed. */
73 T (gma.ax, 0); // { dg-bogus "\\\[-Warray-bounds" }
74 }
75
76
77 void strcpy_global_array (void)
78 {
79 T (gma2[0].a1, 0);
80 T (gma2[0].a1, 1); // { dg-warning "'strcpy' offset 5 from the object at 'gma2' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 4" }
81 T (gma2[0].a1, 4); // { dg-warning "'strcpy' offset \\\[5, 8] from the object at 'gma2' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 4" }
82
83 T (gma2[0].a2, 1);
84 T (gma2[0].a2, 2); // { dg-warning "'strcpy' offset 7 from the object at 'gma2' is out of the bounds of referenced subobject 'a2' with type 'char\\\[2]' at offset 5" }
85
86 T (gma2[0].a3, 2);
87 T (gma2[0].a3, 3); // { dg-warning "'strcpy' offset 10 from the object at 'gma2' is out of the bounds of referenced subobject 'a3' with type 'char\\\[3]' at offset 7" }
88
89 T (gma2[0].a4, 3);
90 T (gma2[0].a4, 4); // { dg-warning "'strcpy' offset 14 from the object at 'gma2' is out of the bounds of referenced subobject 'a4' with type 'char\\\[4]' at offset 10" }
91
92 T (gma2[0].a5, 4);
93 T (gma2[0].a5, 5); // { dg-warning "'strcpy' offset 19 from the object at 'gma2' is out of the bounds of referenced subobject 'a5' with type 'char\\\[5]' at offset 14" }
94
95 T (gma2[0].a17, 16);
96 T (gma2[0].a17, 17); // { dg-warning "'strcpy' offset 157 from the object at 'gma2' is out of the bounds of referenced subobject 'a17' with type 'char\\\[17]' at offset 140" }
97
98 /* GMA2 is external but because it's an array its definition in another
99 translation unit may not provide an initializer for the flexible array
100 member. Verify that a warning is issued for access to it. */
101 T (gma2[0].ax, 1); // { dg-warning "'strcpy' offset \\\[157, 158] from the object at 'gma2' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 157" }
102 T (gma2[0].ax, 7); // { dg-warning "'strcpy' offset \\\[157, 164] from the object at 'gma2' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 157" }
103
104 /* IGMA2_ is internal and provides no definition for the flexible array
105 member. Verify that a warning is issued for out-of-bounds accesses
106 to it. */
107 T (igma2_[0].ax, 1); // { dg-warning "'strcpy' offset \\\[157, 158] from the object at 'igma2_' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 157" }
108
109 T (igma_3.ax, 0);
110 T (igma_3.ax, 1);
111 T (igma_3.ax, 1);
112 T (igma_3.ax, 3); // { dg-warning " offset 160 " }
113 T (igma_3.ax, 9); // { dg-warning " offset \\\[160, 166] " }
114 }
115
116
117 void strcpy_local (void)
118 {
119 struct MA17 lma;
120
121 T (lma.a1, 0);
122 T (lma.a1, 1); // { dg-warning "'strcpy' offset 5 from the object at 'lma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 4" }
123 T (lma.a1, 4); // { dg-warning "'strcpy' offset \\\[5, 8] from the object at 'lma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 4" }
124
125 T (lma.a2, 1);
126 T (lma.a2, 2); // { dg-warning "'strcpy' offset 7 from the object at 'lma' is out of the bounds of referenced subobject 'a2' with type 'char\\\[2]' at offset 5" }
127
128 T (lma.a3, 2);
129 T (lma.a3, 3); // { dg-warning "'strcpy' offset 10 from the object at 'lma' is out of the bounds of referenced subobject 'a3' with type 'char\\\[3]' at offset 7" }
130
131 T (lma.a4, 3);
132 T (lma.a4, 4); // { dg-warning "'strcpy' offset 14 from the object at 'lma' is out of the bounds of referenced subobject 'a4' with type 'char\\\[4]' at offset 10" }
133
134 T (lma.a5, 4);
135 T (lma.a5, 5); // { dg-warning "'strcpy' offset 19 from the object at 'lma' is out of the bounds of referenced subobject 'a5' with type 'char\\\[5]' at offset 14" }
136
137 T (lma.a17, 16);
138 T (lma.a17, 17); // { dg-warning "'strcpy' offset 157 from the object at 'lma' is out of the bounds of referenced subobject 'a17' with type 'char\\\[17]' at offset 140" }
139
140 T (lma.ax, 0); // { dg-warning "'strcpy' offset 157 from the object at 'lma' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 157" }
141 }
142
143
144 void strcpy_ref (struct MA17 *pma)
145 {
146 T (pma->a1, 0);
147 T (pma->a1, 1); // { dg-warning "'strcpy' offset 5 from the object at 'pma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 4" }
148 T (pma->a1, 4); // { dg-warning "'strcpy' offset \\\[5, 8] from the object at 'pma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 4" }
149
150 T (pma->a2, 1);
151 T (pma->a2, 2); // { dg-warning "'strcpy' offset 7 from the object at 'pma' is out of the bounds of referenced subobject 'a2' with type 'char\\\[2]' at offset 5" }
152
153 T (pma->a3, 2);
154 T (pma->a3, 3); // { dg-warning "'strcpy' offset 10 from the object at 'pma' is out of the bounds of referenced subobject 'a3' with type 'char\\\[3]' at offset 7" }
155
156 T (pma->a4, 3);
157 T (pma->a4, 4); // { dg-warning "'strcpy' offset 14 from the object at 'pma' is out of the bounds of referenced subobject 'a4' with type 'char\\\[4]' at offset 10" }
158
159 T (pma->a5, 4);
160 T (pma->a5, 5); // { dg-warning "'strcpy' offset 19 from the object at 'pma' is out of the bounds of referenced subobject 'a5' with type 'char\\\[5]' at offset 14" }
161
162 T (pma->a17, 16);
163 T (pma->a17, 17); // { dg-warning "'strcpy' offset 157 from the object at 'pma' is out of the bounds of referenced subobject 'a17' with type 'char\\\[17]' at offset 140" }
164
165 T (pma->ax, 0);
166 T ((*pma).ax, 8);
167 T (pma[0].ax, 9);
168
169 SA (__builtin_offsetof (struct MA17, a1) == 4
170 && sizeof (struct MA17) == 157);
171
172 T (pma[1].a1, 0);
173 T (pma[1].a1, 1); // { dg-warning "'strcpy' offset 162 from the object at 'pma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 161" }
174 T (pma[1].a1, 4); // { dg-warning "'strcpy' offset \\\[162, 165] from the object at 'pma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset 161" }
175
176 T (pma[1].a2, 1);
177 T (pma[1].a2, 2); // { dg-warning "'strcpy' offset 164 from the object at 'pma' is out of the bounds of referenced subobject 'a2' with type 'char\\\[2]' at offset 162" }
178
179 T (pma[1].a3, 2);
180 T (pma[1].a3, 3); // { dg-warning "'strcpy' offset 167 from the object at 'pma' is out of the bounds of referenced subobject 'a3' with type 'char\\\[3]' at offset 164" }
181
182 T (pma[1].a4, 3);
183 T (pma[1].a4, 4); // { dg-warning "'strcpy' offset 171 from the object at 'pma' is out of the bounds of referenced subobject 'a4' with type 'char\\\[4]' at offset 167" }
184
185 T (pma[1].a5, 4);
186 T (pma[1].a5, 5); // { dg-warning "'strcpy' offset 176 from the object at 'pma' is out of the bounds of referenced subobject 'a5' with type 'char\\\[5]' at offset 171" }
187
188 T (pma[1].a17, 16);
189 T (pma[1].a17, 17); // { dg-warning "'strcpy' offset 314 from the object at 'pma' is out of the bounds of referenced subobject 'a17' with type 'char\\\[17]' at offset 297" }
190
191 /* Since PMA points to an array of structs, accessing the flexible
192 member of any of the elements of the array except for the last one
193 would necessarily access a part of the next element of the enclosing
194 array. The warning assumes that PMA doesn't point to the last element
195 of the array which could in theory have nonzero elements without
196 overlapping other objects. */
197 T (pma[1].ax, 0); // { dg-warning "'strcpy' offset 314 from the object at 'pma' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 314" }
198 T ((pma + 1)->ax, 1); // { dg-warning "'strcpy' offset \\\[314, 315] from the object at 'pma' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 314" }
199 T ((pma + 1)[1].ax, 2); // { dg-warning "'strcpy' offset \\\[471, 473] from the object at 'pma' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 471" }
200 T ((*(pma + 2)).ax, 2); // { dg-warning "'strcpy' offset \\\[471, 473] from the object at 'pma' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 471" }
201 T (pma[3].ax, 9); // { dg-warning "'strcpy' offset \\\[628, 637] from the object at 'pma' is out of the bounds of referenced subobject 'ax' with type 'char\\\[]' at offset 628" }
202
203 T (pma[-1].a1, 0);
204 T (pma[-1].a1, 1); // { dg-warning "'strcpy' offset -152 from the object at 'pma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset -153" }
205 T (pma[-1].a1, 4); // { dg-warning "'strcpy' offset \\\[-152, -149] from the object at 'pma' is out of the bounds of referenced subobject 'a1' with type 'char\\\[1]' at offset -153" }
206 }
207
208 struct MA3
209 {
210 char a4[4]; // { dg-message "'a4' declared here" }
211 char a3[3]; // { dg-message "'a3' declared here" }
212 char c;
213 };
214
215 void strcpy_ref_note (struct MA17 *pma, struct MA3 *pma3)
216 {
217 T (pma3[-1].a4, 0);
218 T (pma3[-1].a4, 1);
219 T (pma3[-1].a4, 2);
220 T (pma3[-1].a4, 3);
221 T (pma3[-1].a4, 4); // { dg-warning "'strcpy' offset -4 from the object at 'pma3' is out of the bounds of referenced subobject 'a4' with type 'char\\\[4]' at offset -8" }
222 T (pma3[-1].a4, 5); // { dg-warning "'strcpy' offset \\\[-4, -3] from the object at 'pma3' is out of the bounds of referenced subobject 'a4' with type 'char\\\[4]' at offset -8" }
223
224 T (pma3[-1].a3, 0);
225 T (pma3[-1].a3, 1);
226 T (pma3[-1].a3, 2);
227 T (pma3[-1].a3, 3); // { dg-warning "'strcpy' offset -1 from the object at 'pma3' is out of the bounds of referenced subobject 'a3' with type 'char\\\[3]' at offset -4" }
228 T (pma3[-1].a3, 4); // { dg-warning "'strcpy' offset \\\[-1, 0] from the object at 'pma3' is out of the bounds of referenced subobject 'a3' with type 'char\\\[3]' at offset -4" }
229 }
230
231
232 void strncpy_vla_member (unsigned n)
233 {
234 struct VarLenStruct {
235 char a4[4], an[n], bn[n];
236 } x;
237
238 sink (&x);
239
240 strncpy (x.bn, x.a4, sizeof x.bn);
241 sink (&x);
242
243 strncpy (x.a4, x.bn, sizeof x.a4);
244 x.a4[sizeof x.a4 - 1] = '\0';
245 sink (&x);
246
247 strncpy (x.a4, x.bn, n);
248 sink (&x);
249
250 strncpy (x.an, x.bn, sizeof x.bn); /* { dg-bogus "\\\[-Warray-bounds" } */
251 sink (&x);
252 }