1 // SPDX-License-Identifier: (GPL-2.0-or-later 1 // SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
2 /* 2 /*
3 * libfdt - Flat Device Tree manipulation 3 * libfdt - Flat Device Tree manipulation
4 * Copyright (C) 2006 David Gibson, IBM Corpor 4 * Copyright (C) 2006 David Gibson, IBM Corporation.
5 */ 5 */
6 #include "libfdt_env.h" 6 #include "libfdt_env.h"
7 7
8 #include <fdt.h> 8 #include <fdt.h>
9 #include <libfdt.h> 9 #include <libfdt.h>
10 10
11 #include "libfdt_internal.h" 11 #include "libfdt_internal.h"
12 12
13 /* 13 /*
14 * Minimal sanity check for a read-only tree. 14 * Minimal sanity check for a read-only tree. fdt_ro_probe_() checks
15 * that the given buffer contains what appears 15 * that the given buffer contains what appears to be a flattened
16 * device tree with sane information in its he 16 * device tree with sane information in its header.
17 */ 17 */
18 int32_t fdt_ro_probe_(const void *fdt) 18 int32_t fdt_ro_probe_(const void *fdt)
19 { 19 {
20 uint32_t totalsize = fdt_totalsize(fdt 20 uint32_t totalsize = fdt_totalsize(fdt);
21 21
22 if (can_assume(VALID_DTB)) 22 if (can_assume(VALID_DTB))
23 return totalsize; 23 return totalsize;
24 24
25 /* The device tree must be at an 8-byt <<
26 if ((uintptr_t)fdt & 7) <<
27 return -FDT_ERR_ALIGNMENT; <<
28 <<
29 if (fdt_magic(fdt) == FDT_MAGIC) { 25 if (fdt_magic(fdt) == FDT_MAGIC) {
30 /* Complete tree */ 26 /* Complete tree */
31 if (!can_assume(LATEST)) { 27 if (!can_assume(LATEST)) {
32 if (fdt_version(fdt) < 28 if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
33 return -FDT_ER 29 return -FDT_ERR_BADVERSION;
34 if (fdt_last_comp_vers 30 if (fdt_last_comp_version(fdt) >
35 FDT_LA 31 FDT_LAST_SUPPORTED_VERSION)
36 return -FDT_ER 32 return -FDT_ERR_BADVERSION;
37 } 33 }
38 } else if (fdt_magic(fdt) == FDT_SW_MA 34 } else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
39 /* Unfinished sequential-write 35 /* Unfinished sequential-write blob */
40 if (!can_assume(VALID_INPUT) & 36 if (!can_assume(VALID_INPUT) && fdt_size_dt_struct(fdt) == 0)
41 return -FDT_ERR_BADSTA 37 return -FDT_ERR_BADSTATE;
42 } else { 38 } else {
43 return -FDT_ERR_BADMAGIC; 39 return -FDT_ERR_BADMAGIC;
44 } 40 }
45 41
46 if (totalsize < INT32_MAX) 42 if (totalsize < INT32_MAX)
47 return totalsize; 43 return totalsize;
48 else 44 else
49 return -FDT_ERR_TRUNCATED; 45 return -FDT_ERR_TRUNCATED;
50 } 46 }
51 47
52 static int check_off_(uint32_t hdrsize, uint32 48 static int check_off_(uint32_t hdrsize, uint32_t totalsize, uint32_t off)
53 { 49 {
54 return (off >= hdrsize) && (off <= tot 50 return (off >= hdrsize) && (off <= totalsize);
55 } 51 }
56 52
57 static int check_block_(uint32_t hdrsize, uint 53 static int check_block_(uint32_t hdrsize, uint32_t totalsize,
58 uint32_t base, uint32_ 54 uint32_t base, uint32_t size)
59 { 55 {
60 if (!check_off_(hdrsize, totalsize, ba 56 if (!check_off_(hdrsize, totalsize, base))
61 return 0; /* block start out o 57 return 0; /* block start out of bounds */
62 if ((base + size) < base) 58 if ((base + size) < base)
63 return 0; /* overflow */ 59 return 0; /* overflow */
64 if (!check_off_(hdrsize, totalsize, ba 60 if (!check_off_(hdrsize, totalsize, base + size))
65 return 0; /* block end out of 61 return 0; /* block end out of bounds */
66 return 1; 62 return 1;
67 } 63 }
68 64
69 size_t fdt_header_size_(uint32_t version) 65 size_t fdt_header_size_(uint32_t version)
70 { 66 {
71 if (version <= 1) 67 if (version <= 1)
72 return FDT_V1_SIZE; 68 return FDT_V1_SIZE;
73 else if (version <= 2) 69 else if (version <= 2)
74 return FDT_V2_SIZE; 70 return FDT_V2_SIZE;
75 else if (version <= 3) 71 else if (version <= 3)
76 return FDT_V3_SIZE; 72 return FDT_V3_SIZE;
77 else if (version <= 16) 73 else if (version <= 16)
78 return FDT_V16_SIZE; 74 return FDT_V16_SIZE;
79 else 75 else
80 return FDT_V17_SIZE; 76 return FDT_V17_SIZE;
81 } 77 }
82 78
83 size_t fdt_header_size(const void *fdt) 79 size_t fdt_header_size(const void *fdt)
84 { 80 {
85 return can_assume(LATEST) ? FDT_V17_SI 81 return can_assume(LATEST) ? FDT_V17_SIZE :
86 fdt_header_size_(fdt_version(f 82 fdt_header_size_(fdt_version(fdt));
87 } 83 }
88 84
89 int fdt_check_header(const void *fdt) 85 int fdt_check_header(const void *fdt)
90 { 86 {
91 size_t hdrsize; 87 size_t hdrsize;
92 88
93 /* The device tree must be at an 8-byt <<
94 if ((uintptr_t)fdt & 7) <<
95 return -FDT_ERR_ALIGNMENT; <<
96 <<
97 if (fdt_magic(fdt) != FDT_MAGIC) 89 if (fdt_magic(fdt) != FDT_MAGIC)
98 return -FDT_ERR_BADMAGIC; 90 return -FDT_ERR_BADMAGIC;
99 if (!can_assume(LATEST)) { 91 if (!can_assume(LATEST)) {
100 if ((fdt_version(fdt) < FDT_FI 92 if ((fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
101 || (fdt_last_comp_version( 93 || (fdt_last_comp_version(fdt) >
102 FDT_LAST_SUPPORTED_VER 94 FDT_LAST_SUPPORTED_VERSION))
103 return -FDT_ERR_BADVER 95 return -FDT_ERR_BADVERSION;
104 if (fdt_version(fdt) < fdt_las 96 if (fdt_version(fdt) < fdt_last_comp_version(fdt))
105 return -FDT_ERR_BADVER 97 return -FDT_ERR_BADVERSION;
106 } 98 }
107 hdrsize = fdt_header_size(fdt); 99 hdrsize = fdt_header_size(fdt);
108 if (!can_assume(VALID_DTB)) { 100 if (!can_assume(VALID_DTB)) {
>> 101
109 if ((fdt_totalsize(fdt) < hdrs 102 if ((fdt_totalsize(fdt) < hdrsize)
110 || (fdt_totalsize(fdt) > I 103 || (fdt_totalsize(fdt) > INT_MAX))
111 return -FDT_ERR_TRUNCA 104 return -FDT_ERR_TRUNCATED;
112 105
113 /* Bounds check memrsv block * 106 /* Bounds check memrsv block */
114 if (!check_off_(hdrsize, fdt_t 107 if (!check_off_(hdrsize, fdt_totalsize(fdt),
115 fdt_off_mem_rs 108 fdt_off_mem_rsvmap(fdt)))
116 return -FDT_ERR_TRUNCA 109 return -FDT_ERR_TRUNCATED;
>> 110 }
117 111
>> 112 if (!can_assume(VALID_DTB)) {
118 /* Bounds check structure bloc 113 /* Bounds check structure block */
119 if (!can_assume(LATEST) && fdt 114 if (!can_assume(LATEST) && fdt_version(fdt) < 17) {
120 if (!check_off_(hdrsiz 115 if (!check_off_(hdrsize, fdt_totalsize(fdt),
121 fdt_of 116 fdt_off_dt_struct(fdt)))
122 return -FDT_ER 117 return -FDT_ERR_TRUNCATED;
123 } else { 118 } else {
124 if (!check_block_(hdrs 119 if (!check_block_(hdrsize, fdt_totalsize(fdt),
125 fdt_ 120 fdt_off_dt_struct(fdt),
126 fdt_ 121 fdt_size_dt_struct(fdt)))
127 return -FDT_ER 122 return -FDT_ERR_TRUNCATED;
128 } 123 }
129 124
130 /* Bounds check strings block 125 /* Bounds check strings block */
131 if (!check_block_(hdrsize, fdt 126 if (!check_block_(hdrsize, fdt_totalsize(fdt),
132 fdt_off_dt_s 127 fdt_off_dt_strings(fdt),
133 fdt_size_dt_ 128 fdt_size_dt_strings(fdt)))
134 return -FDT_ERR_TRUNCA 129 return -FDT_ERR_TRUNCATED;
135 } 130 }
136 131
137 return 0; 132 return 0;
138 } 133 }
139 134
140 const void *fdt_offset_ptr(const void *fdt, in 135 const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
141 { 136 {
142 unsigned int uoffset = offset; 137 unsigned int uoffset = offset;
143 unsigned int absoffset = offset + fdt_ 138 unsigned int absoffset = offset + fdt_off_dt_struct(fdt);
144 139
145 if (offset < 0) 140 if (offset < 0)
146 return NULL; 141 return NULL;
147 142
148 if (!can_assume(VALID_INPUT)) 143 if (!can_assume(VALID_INPUT))
149 if ((absoffset < uoffset) 144 if ((absoffset < uoffset)
150 || ((absoffset + len) < ab 145 || ((absoffset + len) < absoffset)
151 || (absoffset + len) > fdt 146 || (absoffset + len) > fdt_totalsize(fdt))
152 return NULL; 147 return NULL;
153 148
154 if (can_assume(LATEST) || fdt_version( 149 if (can_assume(LATEST) || fdt_version(fdt) >= 0x11)
155 if (((uoffset + len) < uoffset 150 if (((uoffset + len) < uoffset)
156 || ((offset + len) > fdt_s 151 || ((offset + len) > fdt_size_dt_struct(fdt)))
157 return NULL; 152 return NULL;
158 153
159 return fdt_offset_ptr_(fdt, offset); 154 return fdt_offset_ptr_(fdt, offset);
160 } 155 }
161 156
162 uint32_t fdt_next_tag(const void *fdt, int sta 157 uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
163 { 158 {
164 const fdt32_t *tagp, *lenp; 159 const fdt32_t *tagp, *lenp;
165 uint32_t tag, len, sum; !! 160 uint32_t tag;
166 int offset = startoffset; 161 int offset = startoffset;
167 const char *p; 162 const char *p;
168 163
169 *nextoffset = -FDT_ERR_TRUNCATED; 164 *nextoffset = -FDT_ERR_TRUNCATED;
170 tagp = fdt_offset_ptr(fdt, offset, FDT 165 tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);
171 if (!can_assume(VALID_DTB) && !tagp) 166 if (!can_assume(VALID_DTB) && !tagp)
172 return FDT_END; /* premature e 167 return FDT_END; /* premature end */
173 tag = fdt32_to_cpu(*tagp); 168 tag = fdt32_to_cpu(*tagp);
174 offset += FDT_TAGSIZE; 169 offset += FDT_TAGSIZE;
175 170
176 *nextoffset = -FDT_ERR_BADSTRUCTURE; 171 *nextoffset = -FDT_ERR_BADSTRUCTURE;
177 switch (tag) { 172 switch (tag) {
178 case FDT_BEGIN_NODE: 173 case FDT_BEGIN_NODE:
179 /* skip name */ 174 /* skip name */
180 do { 175 do {
181 p = fdt_offset_ptr(fdt 176 p = fdt_offset_ptr(fdt, offset++, 1);
182 } while (p && (*p != '\0')); 177 } while (p && (*p != '\0'));
183 if (!can_assume(VALID_DTB) && 178 if (!can_assume(VALID_DTB) && !p)
184 return FDT_END; /* pre 179 return FDT_END; /* premature end */
185 break; 180 break;
186 181
187 case FDT_PROP: 182 case FDT_PROP:
188 lenp = fdt_offset_ptr(fdt, off 183 lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
189 if (!can_assume(VALID_DTB) && 184 if (!can_assume(VALID_DTB) && !lenp)
190 return FDT_END; /* pre 185 return FDT_END; /* premature end */
191 <<
192 len = fdt32_to_cpu(*lenp); <<
193 sum = len + offset; <<
194 if (!can_assume(VALID_DTB) && <<
195 (INT_MAX <= sum || sum < ( <<
196 return FDT_END; /* pre <<
197 <<
198 /* skip-name offset, length an 186 /* skip-name offset, length and value */
199 offset += sizeof(struct fdt_pr !! 187 offset += sizeof(struct fdt_property) - FDT_TAGSIZE
200 !! 188 + fdt32_to_cpu(*lenp);
201 if (!can_assume(LATEST) && 189 if (!can_assume(LATEST) &&
202 fdt_version(fdt) < 0x10 && !! 190 fdt_version(fdt) < 0x10 && fdt32_to_cpu(*lenp) >= 8 &&
203 ((offset - len) % 8) != 0) !! 191 ((offset - fdt32_to_cpu(*lenp)) % 8) != 0)
204 offset += 4; 192 offset += 4;
205 break; 193 break;
206 194
207 case FDT_END: 195 case FDT_END:
208 case FDT_END_NODE: 196 case FDT_END_NODE:
209 case FDT_NOP: 197 case FDT_NOP:
210 break; 198 break;
211 199
212 default: 200 default:
213 return FDT_END; 201 return FDT_END;
214 } 202 }
215 203
216 if (!fdt_offset_ptr(fdt, startoffset, 204 if (!fdt_offset_ptr(fdt, startoffset, offset - startoffset))
217 return FDT_END; /* premature e 205 return FDT_END; /* premature end */
218 206
219 *nextoffset = FDT_TAGALIGN(offset); 207 *nextoffset = FDT_TAGALIGN(offset);
220 return tag; 208 return tag;
221 } 209 }
222 210
223 int fdt_check_node_offset_(const void *fdt, in 211 int fdt_check_node_offset_(const void *fdt, int offset)
224 { 212 {
225 if (!can_assume(VALID_INPUT) 213 if (!can_assume(VALID_INPUT)
226 && ((offset < 0) || (offset % FDT_ 214 && ((offset < 0) || (offset % FDT_TAGSIZE)))
227 return -FDT_ERR_BADOFFSET; 215 return -FDT_ERR_BADOFFSET;
228 216
229 if (fdt_next_tag(fdt, offset, &offset) 217 if (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE)
230 return -FDT_ERR_BADOFFSET; 218 return -FDT_ERR_BADOFFSET;
231 219
232 return offset; 220 return offset;
233 } 221 }
234 222
235 int fdt_check_prop_offset_(const void *fdt, in 223 int fdt_check_prop_offset_(const void *fdt, int offset)
236 { 224 {
237 if (!can_assume(VALID_INPUT) 225 if (!can_assume(VALID_INPUT)
238 && ((offset < 0) || (offset % FDT_ 226 && ((offset < 0) || (offset % FDT_TAGSIZE)))
239 return -FDT_ERR_BADOFFSET; 227 return -FDT_ERR_BADOFFSET;
240 228
241 if (fdt_next_tag(fdt, offset, &offset) 229 if (fdt_next_tag(fdt, offset, &offset) != FDT_PROP)
242 return -FDT_ERR_BADOFFSET; 230 return -FDT_ERR_BADOFFSET;
243 231
244 return offset; 232 return offset;
245 } 233 }
246 234
247 int fdt_next_node(const void *fdt, int offset, 235 int fdt_next_node(const void *fdt, int offset, int *depth)
248 { 236 {
249 int nextoffset = 0; 237 int nextoffset = 0;
250 uint32_t tag; 238 uint32_t tag;
251 239
252 if (offset >= 0) 240 if (offset >= 0)
253 if ((nextoffset = fdt_check_no 241 if ((nextoffset = fdt_check_node_offset_(fdt, offset)) < 0)
254 return nextoffset; 242 return nextoffset;
255 243
256 do { 244 do {
257 offset = nextoffset; 245 offset = nextoffset;
258 tag = fdt_next_tag(fdt, offset 246 tag = fdt_next_tag(fdt, offset, &nextoffset);
259 247
260 switch (tag) { 248 switch (tag) {
261 case FDT_PROP: 249 case FDT_PROP:
262 case FDT_NOP: 250 case FDT_NOP:
263 break; 251 break;
264 252
265 case FDT_BEGIN_NODE: 253 case FDT_BEGIN_NODE:
266 if (depth) 254 if (depth)
267 (*depth)++; 255 (*depth)++;
268 break; 256 break;
269 257
270 case FDT_END_NODE: 258 case FDT_END_NODE:
271 if (depth && ((--(*dep 259 if (depth && ((--(*depth)) < 0))
272 return nextoff 260 return nextoffset;
273 break; 261 break;
274 262
275 case FDT_END: 263 case FDT_END:
276 if ((nextoffset >= 0) 264 if ((nextoffset >= 0)
277 || ((nextoffset == 265 || ((nextoffset == -FDT_ERR_TRUNCATED) && !depth))
278 return -FDT_ER 266 return -FDT_ERR_NOTFOUND;
279 else 267 else
280 return nextoff 268 return nextoffset;
281 } 269 }
282 } while (tag != FDT_BEGIN_NODE); 270 } while (tag != FDT_BEGIN_NODE);
283 271
284 return offset; 272 return offset;
285 } 273 }
286 274
287 int fdt_first_subnode(const void *fdt, int off 275 int fdt_first_subnode(const void *fdt, int offset)
288 { 276 {
289 int depth = 0; 277 int depth = 0;
290 278
291 offset = fdt_next_node(fdt, offset, &d 279 offset = fdt_next_node(fdt, offset, &depth);
292 if (offset < 0 || depth != 1) 280 if (offset < 0 || depth != 1)
293 return -FDT_ERR_NOTFOUND; 281 return -FDT_ERR_NOTFOUND;
294 282
295 return offset; 283 return offset;
296 } 284 }
297 285
298 int fdt_next_subnode(const void *fdt, int offs 286 int fdt_next_subnode(const void *fdt, int offset)
299 { 287 {
300 int depth = 1; 288 int depth = 1;
301 289
302 /* 290 /*
303 * With respect to the parent, the dep 291 * With respect to the parent, the depth of the next subnode will be
304 * the same as the last. 292 * the same as the last.
305 */ 293 */
306 do { 294 do {
307 offset = fdt_next_node(fdt, of 295 offset = fdt_next_node(fdt, offset, &depth);
308 if (offset < 0 || depth < 1) 296 if (offset < 0 || depth < 1)
309 return -FDT_ERR_NOTFOU 297 return -FDT_ERR_NOTFOUND;
310 } while (depth > 1); 298 } while (depth > 1);
311 299
312 return offset; 300 return offset;
313 } 301 }
314 302
315 const char *fdt_find_string_(const char *strta 303 const char *fdt_find_string_(const char *strtab, int tabsize, const char *s)
316 { 304 {
317 int len = strlen(s) + 1; 305 int len = strlen(s) + 1;
318 const char *last = strtab + tabsize - 306 const char *last = strtab + tabsize - len;
319 const char *p; 307 const char *p;
320 308
321 for (p = strtab; p <= last; p++) 309 for (p = strtab; p <= last; p++)
322 if (memcmp(p, s, len) == 0) 310 if (memcmp(p, s, len) == 0)
323 return p; 311 return p;
324 return NULL; 312 return NULL;
325 } 313 }
326 314
327 int fdt_move(const void *fdt, void *buf, int b 315 int fdt_move(const void *fdt, void *buf, int bufsize)
328 { 316 {
329 if (!can_assume(VALID_INPUT) && bufsiz 317 if (!can_assume(VALID_INPUT) && bufsize < 0)
330 return -FDT_ERR_NOSPACE; 318 return -FDT_ERR_NOSPACE;
331 319
332 FDT_RO_PROBE(fdt); 320 FDT_RO_PROBE(fdt);
333 321
334 if (fdt_totalsize(fdt) > (unsigned int 322 if (fdt_totalsize(fdt) > (unsigned int)bufsize)
335 return -FDT_ERR_NOSPACE; 323 return -FDT_ERR_NOSPACE;
336 324
337 memmove(buf, fdt, fdt_totalsize(fdt)); 325 memmove(buf, fdt, fdt_totalsize(fdt));
338 return 0; 326 return 0;
339 } 327 }
340 328
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