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69b693f0 MKL |
1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* Copyright (c) 2018 Facebook */ | |
3 | ||
4 | #include <uapi/linux/btf.h> | |
5 | #include <uapi/linux/types.h> | |
b00b8dae | 6 | #include <linux/seq_file.h> |
69b693f0 | 7 | #include <linux/compiler.h> |
2667a262 | 8 | #include <linux/ctype.h> |
69b693f0 MKL |
9 | #include <linux/errno.h> |
10 | #include <linux/slab.h> | |
f56a653c MKL |
11 | #include <linux/anon_inodes.h> |
12 | #include <linux/file.h> | |
69b693f0 MKL |
13 | #include <linux/uaccess.h> |
14 | #include <linux/kernel.h> | |
78958fca | 15 | #include <linux/idr.h> |
f80442a4 | 16 | #include <linux/sort.h> |
69b693f0 MKL |
17 | #include <linux/bpf_verifier.h> |
18 | #include <linux/btf.h> | |
19 | ||
20 | /* BTF (BPF Type Format) is the meta data format which describes | |
21 | * the data types of BPF program/map. Hence, it basically focus | |
22 | * on the C programming language which the modern BPF is primary | |
23 | * using. | |
24 | * | |
25 | * ELF Section: | |
26 | * ~~~~~~~~~~~ | |
27 | * The BTF data is stored under the ".BTF" ELF section | |
28 | * | |
29 | * struct btf_type: | |
30 | * ~~~~~~~~~~~~~~~ | |
31 | * Each 'struct btf_type' object describes a C data type. | |
32 | * Depending on the type it is describing, a 'struct btf_type' | |
33 | * object may be followed by more data. F.e. | |
34 | * To describe an array, 'struct btf_type' is followed by | |
35 | * 'struct btf_array'. | |
36 | * | |
37 | * 'struct btf_type' and any extra data following it are | |
38 | * 4 bytes aligned. | |
39 | * | |
40 | * Type section: | |
41 | * ~~~~~~~~~~~~~ | |
42 | * The BTF type section contains a list of 'struct btf_type' objects. | |
43 | * Each one describes a C type. Recall from the above section | |
44 | * that a 'struct btf_type' object could be immediately followed by extra | |
45 | * data in order to desribe some particular C types. | |
46 | * | |
47 | * type_id: | |
48 | * ~~~~~~~ | |
49 | * Each btf_type object is identified by a type_id. The type_id | |
50 | * is implicitly implied by the location of the btf_type object in | |
51 | * the BTF type section. The first one has type_id 1. The second | |
52 | * one has type_id 2...etc. Hence, an earlier btf_type has | |
53 | * a smaller type_id. | |
54 | * | |
55 | * A btf_type object may refer to another btf_type object by using | |
56 | * type_id (i.e. the "type" in the "struct btf_type"). | |
57 | * | |
58 | * NOTE that we cannot assume any reference-order. | |
59 | * A btf_type object can refer to an earlier btf_type object | |
60 | * but it can also refer to a later btf_type object. | |
61 | * | |
62 | * For example, to describe "const void *". A btf_type | |
63 | * object describing "const" may refer to another btf_type | |
64 | * object describing "void *". This type-reference is done | |
65 | * by specifying type_id: | |
66 | * | |
67 | * [1] CONST (anon) type_id=2 | |
68 | * [2] PTR (anon) type_id=0 | |
69 | * | |
70 | * The above is the btf_verifier debug log: | |
71 | * - Each line started with "[?]" is a btf_type object | |
72 | * - [?] is the type_id of the btf_type object. | |
73 | * - CONST/PTR is the BTF_KIND_XXX | |
74 | * - "(anon)" is the name of the type. It just | |
75 | * happens that CONST and PTR has no name. | |
76 | * - type_id=XXX is the 'u32 type' in btf_type | |
77 | * | |
78 | * NOTE: "void" has type_id 0 | |
79 | * | |
80 | * String section: | |
81 | * ~~~~~~~~~~~~~~ | |
82 | * The BTF string section contains the names used by the type section. | |
83 | * Each string is referred by an "offset" from the beginning of the | |
84 | * string section. | |
85 | * | |
86 | * Each string is '\0' terminated. | |
87 | * | |
88 | * The first character in the string section must be '\0' | |
89 | * which is used to mean 'anonymous'. Some btf_type may not | |
90 | * have a name. | |
91 | */ | |
92 | ||
93 | /* BTF verification: | |
94 | * | |
95 | * To verify BTF data, two passes are needed. | |
96 | * | |
97 | * Pass #1 | |
98 | * ~~~~~~~ | |
99 | * The first pass is to collect all btf_type objects to | |
100 | * an array: "btf->types". | |
101 | * | |
102 | * Depending on the C type that a btf_type is describing, | |
103 | * a btf_type may be followed by extra data. We don't know | |
104 | * how many btf_type is there, and more importantly we don't | |
105 | * know where each btf_type is located in the type section. | |
106 | * | |
107 | * Without knowing the location of each type_id, most verifications | |
108 | * cannot be done. e.g. an earlier btf_type may refer to a later | |
109 | * btf_type (recall the "const void *" above), so we cannot | |
110 | * check this type-reference in the first pass. | |
111 | * | |
112 | * In the first pass, it still does some verifications (e.g. | |
113 | * checking the name is a valid offset to the string section). | |
eb3f595d MKL |
114 | * |
115 | * Pass #2 | |
116 | * ~~~~~~~ | |
117 | * The main focus is to resolve a btf_type that is referring | |
118 | * to another type. | |
119 | * | |
120 | * We have to ensure the referring type: | |
121 | * 1) does exist in the BTF (i.e. in btf->types[]) | |
122 | * 2) does not cause a loop: | |
123 | * struct A { | |
124 | * struct B b; | |
125 | * }; | |
126 | * | |
127 | * struct B { | |
128 | * struct A a; | |
129 | * }; | |
130 | * | |
131 | * btf_type_needs_resolve() decides if a btf_type needs | |
132 | * to be resolved. | |
133 | * | |
134 | * The needs_resolve type implements the "resolve()" ops which | |
135 | * essentially does a DFS and detects backedge. | |
136 | * | |
137 | * During resolve (or DFS), different C types have different | |
138 | * "RESOLVED" conditions. | |
139 | * | |
140 | * When resolving a BTF_KIND_STRUCT, we need to resolve all its | |
141 | * members because a member is always referring to another | |
142 | * type. A struct's member can be treated as "RESOLVED" if | |
143 | * it is referring to a BTF_KIND_PTR. Otherwise, the | |
144 | * following valid C struct would be rejected: | |
145 | * | |
146 | * struct A { | |
147 | * int m; | |
148 | * struct A *a; | |
149 | * }; | |
150 | * | |
151 | * When resolving a BTF_KIND_PTR, it needs to keep resolving if | |
152 | * it is referring to another BTF_KIND_PTR. Otherwise, we cannot | |
153 | * detect a pointer loop, e.g.: | |
154 | * BTF_KIND_CONST -> BTF_KIND_PTR -> BTF_KIND_CONST -> BTF_KIND_PTR + | |
155 | * ^ | | |
156 | * +-----------------------------------------+ | |
157 | * | |
69b693f0 MKL |
158 | */ |
159 | ||
b1e8818c | 160 | #define BITS_PER_U128 (sizeof(u64) * BITS_PER_BYTE * 2) |
69b693f0 MKL |
161 | #define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1) |
162 | #define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK) | |
163 | #define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3) | |
164 | #define BITS_ROUNDUP_BYTES(bits) \ | |
165 | (BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits)) | |
166 | ||
9d5f9f70 | 167 | #define BTF_INFO_MASK 0x8f00ffff |
aea2f7b8 MKL |
168 | #define BTF_INT_MASK 0x0fffffff |
169 | #define BTF_TYPE_ID_VALID(type_id) ((type_id) <= BTF_MAX_TYPE) | |
170 | #define BTF_STR_OFFSET_VALID(name_off) ((name_off) <= BTF_MAX_NAME_OFFSET) | |
171 | ||
69b693f0 MKL |
172 | /* 16MB for 64k structs and each has 16 members and |
173 | * a few MB spaces for the string section. | |
174 | * The hard limit is S32_MAX. | |
175 | */ | |
176 | #define BTF_MAX_SIZE (16 * 1024 * 1024) | |
69b693f0 MKL |
177 | |
178 | #define for_each_member(i, struct_type, member) \ | |
179 | for (i = 0, member = btf_type_member(struct_type); \ | |
180 | i < btf_type_vlen(struct_type); \ | |
181 | i++, member++) | |
182 | ||
eb3f595d MKL |
183 | #define for_each_member_from(i, from, struct_type, member) \ |
184 | for (i = from, member = btf_type_member(struct_type) + from; \ | |
185 | i < btf_type_vlen(struct_type); \ | |
186 | i++, member++) | |
187 | ||
1dc92851 DB |
188 | #define for_each_vsi(i, struct_type, member) \ |
189 | for (i = 0, member = btf_type_var_secinfo(struct_type); \ | |
190 | i < btf_type_vlen(struct_type); \ | |
191 | i++, member++) | |
192 | ||
193 | #define for_each_vsi_from(i, from, struct_type, member) \ | |
194 | for (i = from, member = btf_type_var_secinfo(struct_type) + from; \ | |
195 | i < btf_type_vlen(struct_type); \ | |
196 | i++, member++) | |
197 | ||
78958fca MKL |
198 | static DEFINE_IDR(btf_idr); |
199 | static DEFINE_SPINLOCK(btf_idr_lock); | |
200 | ||
69b693f0 | 201 | struct btf { |
f80442a4 | 202 | void *data; |
69b693f0 | 203 | struct btf_type **types; |
eb3f595d MKL |
204 | u32 *resolved_ids; |
205 | u32 *resolved_sizes; | |
69b693f0 MKL |
206 | const char *strings; |
207 | void *nohdr_data; | |
f80442a4 | 208 | struct btf_header hdr; |
69b693f0 MKL |
209 | u32 nr_types; |
210 | u32 types_size; | |
211 | u32 data_size; | |
f56a653c | 212 | refcount_t refcnt; |
78958fca MKL |
213 | u32 id; |
214 | struct rcu_head rcu; | |
69b693f0 MKL |
215 | }; |
216 | ||
eb3f595d MKL |
217 | enum verifier_phase { |
218 | CHECK_META, | |
219 | CHECK_TYPE, | |
220 | }; | |
221 | ||
222 | struct resolve_vertex { | |
223 | const struct btf_type *t; | |
224 | u32 type_id; | |
225 | u16 next_member; | |
226 | }; | |
227 | ||
228 | enum visit_state { | |
229 | NOT_VISITED, | |
230 | VISITED, | |
231 | RESOLVED, | |
232 | }; | |
233 | ||
234 | enum resolve_mode { | |
235 | RESOLVE_TBD, /* To Be Determined */ | |
236 | RESOLVE_PTR, /* Resolving for Pointer */ | |
237 | RESOLVE_STRUCT_OR_ARRAY, /* Resolving for struct/union | |
238 | * or array | |
239 | */ | |
240 | }; | |
241 | ||
242 | #define MAX_RESOLVE_DEPTH 32 | |
243 | ||
f80442a4 MKL |
244 | struct btf_sec_info { |
245 | u32 off; | |
246 | u32 len; | |
247 | }; | |
248 | ||
69b693f0 MKL |
249 | struct btf_verifier_env { |
250 | struct btf *btf; | |
eb3f595d MKL |
251 | u8 *visit_states; |
252 | struct resolve_vertex stack[MAX_RESOLVE_DEPTH]; | |
69b693f0 MKL |
253 | struct bpf_verifier_log log; |
254 | u32 log_type_id; | |
eb3f595d MKL |
255 | u32 top_stack; |
256 | enum verifier_phase phase; | |
257 | enum resolve_mode resolve_mode; | |
69b693f0 MKL |
258 | }; |
259 | ||
260 | static const char * const btf_kind_str[NR_BTF_KINDS] = { | |
261 | [BTF_KIND_UNKN] = "UNKNOWN", | |
262 | [BTF_KIND_INT] = "INT", | |
263 | [BTF_KIND_PTR] = "PTR", | |
264 | [BTF_KIND_ARRAY] = "ARRAY", | |
265 | [BTF_KIND_STRUCT] = "STRUCT", | |
266 | [BTF_KIND_UNION] = "UNION", | |
267 | [BTF_KIND_ENUM] = "ENUM", | |
268 | [BTF_KIND_FWD] = "FWD", | |
269 | [BTF_KIND_TYPEDEF] = "TYPEDEF", | |
270 | [BTF_KIND_VOLATILE] = "VOLATILE", | |
271 | [BTF_KIND_CONST] = "CONST", | |
272 | [BTF_KIND_RESTRICT] = "RESTRICT", | |
2667a262 MKL |
273 | [BTF_KIND_FUNC] = "FUNC", |
274 | [BTF_KIND_FUNC_PROTO] = "FUNC_PROTO", | |
1dc92851 DB |
275 | [BTF_KIND_VAR] = "VAR", |
276 | [BTF_KIND_DATASEC] = "DATASEC", | |
69b693f0 MKL |
277 | }; |
278 | ||
279 | struct btf_kind_operations { | |
280 | s32 (*check_meta)(struct btf_verifier_env *env, | |
281 | const struct btf_type *t, | |
282 | u32 meta_left); | |
eb3f595d MKL |
283 | int (*resolve)(struct btf_verifier_env *env, |
284 | const struct resolve_vertex *v); | |
179cde8c MKL |
285 | int (*check_member)(struct btf_verifier_env *env, |
286 | const struct btf_type *struct_type, | |
287 | const struct btf_member *member, | |
288 | const struct btf_type *member_type); | |
9d5f9f70 YS |
289 | int (*check_kflag_member)(struct btf_verifier_env *env, |
290 | const struct btf_type *struct_type, | |
291 | const struct btf_member *member, | |
292 | const struct btf_type *member_type); | |
69b693f0 MKL |
293 | void (*log_details)(struct btf_verifier_env *env, |
294 | const struct btf_type *t); | |
b00b8dae MKL |
295 | void (*seq_show)(const struct btf *btf, const struct btf_type *t, |
296 | u32 type_id, void *data, u8 bits_offsets, | |
297 | struct seq_file *m); | |
69b693f0 MKL |
298 | }; |
299 | ||
300 | static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS]; | |
301 | static struct btf_type btf_void; | |
302 | ||
2667a262 MKL |
303 | static int btf_resolve(struct btf_verifier_env *env, |
304 | const struct btf_type *t, u32 type_id); | |
305 | ||
eb3f595d MKL |
306 | static bool btf_type_is_modifier(const struct btf_type *t) |
307 | { | |
308 | /* Some of them is not strictly a C modifier | |
309 | * but they are grouped into the same bucket | |
310 | * for BTF concern: | |
311 | * A type (t) that refers to another | |
312 | * type through t->type AND its size cannot | |
313 | * be determined without following the t->type. | |
314 | * | |
315 | * ptr does not fall into this bucket | |
316 | * because its size is always sizeof(void *). | |
317 | */ | |
318 | switch (BTF_INFO_KIND(t->info)) { | |
319 | case BTF_KIND_TYPEDEF: | |
320 | case BTF_KIND_VOLATILE: | |
321 | case BTF_KIND_CONST: | |
322 | case BTF_KIND_RESTRICT: | |
323 | return true; | |
324 | } | |
325 | ||
326 | return false; | |
327 | } | |
328 | ||
2824ecb7 | 329 | bool btf_type_is_void(const struct btf_type *t) |
eb3f595d | 330 | { |
b47a0bd2 MKL |
331 | return t == &btf_void; |
332 | } | |
333 | ||
334 | static bool btf_type_is_fwd(const struct btf_type *t) | |
335 | { | |
336 | return BTF_INFO_KIND(t->info) == BTF_KIND_FWD; | |
337 | } | |
338 | ||
2667a262 MKL |
339 | static bool btf_type_is_func(const struct btf_type *t) |
340 | { | |
341 | return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC; | |
342 | } | |
343 | ||
344 | static bool btf_type_is_func_proto(const struct btf_type *t) | |
345 | { | |
346 | return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO; | |
347 | } | |
348 | ||
b47a0bd2 MKL |
349 | static bool btf_type_nosize(const struct btf_type *t) |
350 | { | |
2667a262 MKL |
351 | return btf_type_is_void(t) || btf_type_is_fwd(t) || |
352 | btf_type_is_func(t) || btf_type_is_func_proto(t); | |
eb3f595d MKL |
353 | } |
354 | ||
b47a0bd2 | 355 | static bool btf_type_nosize_or_null(const struct btf_type *t) |
eb3f595d | 356 | { |
b47a0bd2 | 357 | return !t || btf_type_nosize(t); |
eb3f595d MKL |
358 | } |
359 | ||
360 | /* union is only a special case of struct: | |
361 | * all its offsetof(member) == 0 | |
362 | */ | |
363 | static bool btf_type_is_struct(const struct btf_type *t) | |
364 | { | |
365 | u8 kind = BTF_INFO_KIND(t->info); | |
366 | ||
367 | return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION; | |
368 | } | |
369 | ||
d83525ca AS |
370 | static bool __btf_type_is_struct(const struct btf_type *t) |
371 | { | |
372 | return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT; | |
373 | } | |
374 | ||
eb3f595d MKL |
375 | static bool btf_type_is_array(const struct btf_type *t) |
376 | { | |
377 | return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY; | |
378 | } | |
379 | ||
380 | static bool btf_type_is_ptr(const struct btf_type *t) | |
381 | { | |
382 | return BTF_INFO_KIND(t->info) == BTF_KIND_PTR; | |
383 | } | |
384 | ||
385 | static bool btf_type_is_int(const struct btf_type *t) | |
386 | { | |
387 | return BTF_INFO_KIND(t->info) == BTF_KIND_INT; | |
388 | } | |
389 | ||
1dc92851 DB |
390 | static bool btf_type_is_var(const struct btf_type *t) |
391 | { | |
392 | return BTF_INFO_KIND(t->info) == BTF_KIND_VAR; | |
393 | } | |
394 | ||
395 | static bool btf_type_is_datasec(const struct btf_type *t) | |
396 | { | |
397 | return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC; | |
398 | } | |
399 | ||
400 | /* Types that act only as a source, not sink or intermediate | |
401 | * type when resolving. | |
402 | */ | |
403 | static bool btf_type_is_resolve_source_only(const struct btf_type *t) | |
404 | { | |
405 | return btf_type_is_var(t) || | |
406 | btf_type_is_datasec(t); | |
407 | } | |
408 | ||
eb3f595d MKL |
409 | /* What types need to be resolved? |
410 | * | |
411 | * btf_type_is_modifier() is an obvious one. | |
412 | * | |
413 | * btf_type_is_struct() because its member refers to | |
414 | * another type (through member->type). | |
1dc92851 DB |
415 | * |
416 | * btf_type_is_var() because the variable refers to | |
417 | * another type. btf_type_is_datasec() holds multiple | |
418 | * btf_type_is_var() types that need resolving. | |
419 | * | |
eb3f595d MKL |
420 | * btf_type_is_array() because its element (array->type) |
421 | * refers to another type. Array can be thought of a | |
422 | * special case of struct while array just has the same | |
423 | * member-type repeated by array->nelems of times. | |
424 | */ | |
425 | static bool btf_type_needs_resolve(const struct btf_type *t) | |
426 | { | |
427 | return btf_type_is_modifier(t) || | |
1dc92851 DB |
428 | btf_type_is_ptr(t) || |
429 | btf_type_is_struct(t) || | |
430 | btf_type_is_array(t) || | |
431 | btf_type_is_var(t) || | |
432 | btf_type_is_datasec(t); | |
eb3f595d MKL |
433 | } |
434 | ||
435 | /* t->size can be used */ | |
436 | static bool btf_type_has_size(const struct btf_type *t) | |
437 | { | |
438 | switch (BTF_INFO_KIND(t->info)) { | |
439 | case BTF_KIND_INT: | |
440 | case BTF_KIND_STRUCT: | |
441 | case BTF_KIND_UNION: | |
442 | case BTF_KIND_ENUM: | |
1dc92851 | 443 | case BTF_KIND_DATASEC: |
eb3f595d MKL |
444 | return true; |
445 | } | |
446 | ||
447 | return false; | |
448 | } | |
449 | ||
69b693f0 MKL |
450 | static const char *btf_int_encoding_str(u8 encoding) |
451 | { | |
452 | if (encoding == 0) | |
453 | return "(none)"; | |
454 | else if (encoding == BTF_INT_SIGNED) | |
455 | return "SIGNED"; | |
456 | else if (encoding == BTF_INT_CHAR) | |
457 | return "CHAR"; | |
458 | else if (encoding == BTF_INT_BOOL) | |
459 | return "BOOL"; | |
69b693f0 MKL |
460 | else |
461 | return "UNKN"; | |
462 | } | |
463 | ||
464 | static u16 btf_type_vlen(const struct btf_type *t) | |
465 | { | |
466 | return BTF_INFO_VLEN(t->info); | |
467 | } | |
468 | ||
9d5f9f70 YS |
469 | static bool btf_type_kflag(const struct btf_type *t) |
470 | { | |
471 | return BTF_INFO_KFLAG(t->info); | |
472 | } | |
473 | ||
474 | static u32 btf_member_bit_offset(const struct btf_type *struct_type, | |
475 | const struct btf_member *member) | |
476 | { | |
477 | return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset) | |
478 | : member->offset; | |
479 | } | |
480 | ||
481 | static u32 btf_member_bitfield_size(const struct btf_type *struct_type, | |
482 | const struct btf_member *member) | |
483 | { | |
484 | return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset) | |
485 | : 0; | |
486 | } | |
487 | ||
69b693f0 MKL |
488 | static u32 btf_type_int(const struct btf_type *t) |
489 | { | |
490 | return *(u32 *)(t + 1); | |
491 | } | |
492 | ||
493 | static const struct btf_array *btf_type_array(const struct btf_type *t) | |
494 | { | |
495 | return (const struct btf_array *)(t + 1); | |
496 | } | |
497 | ||
498 | static const struct btf_member *btf_type_member(const struct btf_type *t) | |
499 | { | |
500 | return (const struct btf_member *)(t + 1); | |
501 | } | |
502 | ||
503 | static const struct btf_enum *btf_type_enum(const struct btf_type *t) | |
504 | { | |
505 | return (const struct btf_enum *)(t + 1); | |
506 | } | |
507 | ||
1dc92851 DB |
508 | static const struct btf_var *btf_type_var(const struct btf_type *t) |
509 | { | |
510 | return (const struct btf_var *)(t + 1); | |
511 | } | |
512 | ||
513 | static const struct btf_var_secinfo *btf_type_var_secinfo(const struct btf_type *t) | |
514 | { | |
515 | return (const struct btf_var_secinfo *)(t + 1); | |
516 | } | |
517 | ||
69b693f0 MKL |
518 | static const struct btf_kind_operations *btf_type_ops(const struct btf_type *t) |
519 | { | |
520 | return kind_ops[BTF_INFO_KIND(t->info)]; | |
521 | } | |
522 | ||
583c5318 | 523 | static bool btf_name_offset_valid(const struct btf *btf, u32 offset) |
69b693f0 | 524 | { |
aea2f7b8 MKL |
525 | return BTF_STR_OFFSET_VALID(offset) && |
526 | offset < btf->hdr.str_len; | |
69b693f0 MKL |
527 | } |
528 | ||
1dc92851 DB |
529 | static bool __btf_name_char_ok(char c, bool first, bool dot_ok) |
530 | { | |
531 | if ((first ? !isalpha(c) : | |
532 | !isalnum(c)) && | |
533 | c != '_' && | |
534 | ((c == '.' && !dot_ok) || | |
535 | c != '.')) | |
536 | return false; | |
537 | return true; | |
538 | } | |
539 | ||
540 | static bool __btf_name_valid(const struct btf *btf, u32 offset, bool dot_ok) | |
2667a262 MKL |
541 | { |
542 | /* offset must be valid */ | |
543 | const char *src = &btf->strings[offset]; | |
544 | const char *src_limit; | |
545 | ||
1dc92851 | 546 | if (!__btf_name_char_ok(*src, true, dot_ok)) |
2667a262 MKL |
547 | return false; |
548 | ||
549 | /* set a limit on identifier length */ | |
550 | src_limit = src + KSYM_NAME_LEN; | |
551 | src++; | |
552 | while (*src && src < src_limit) { | |
1dc92851 | 553 | if (!__btf_name_char_ok(*src, false, dot_ok)) |
2667a262 MKL |
554 | return false; |
555 | src++; | |
556 | } | |
557 | ||
558 | return !*src; | |
559 | } | |
560 | ||
1dc92851 DB |
561 | /* Only C-style identifier is permitted. This can be relaxed if |
562 | * necessary. | |
563 | */ | |
564 | static bool btf_name_valid_identifier(const struct btf *btf, u32 offset) | |
565 | { | |
566 | return __btf_name_valid(btf, offset, false); | |
567 | } | |
568 | ||
569 | static bool btf_name_valid_section(const struct btf *btf, u32 offset) | |
570 | { | |
571 | return __btf_name_valid(btf, offset, true); | |
572 | } | |
573 | ||
23127b33 | 574 | static const char *__btf_name_by_offset(const struct btf *btf, u32 offset) |
69b693f0 | 575 | { |
aea2f7b8 | 576 | if (!offset) |
69b693f0 | 577 | return "(anon)"; |
aea2f7b8 MKL |
578 | else if (offset < btf->hdr.str_len) |
579 | return &btf->strings[offset]; | |
69b693f0 MKL |
580 | else |
581 | return "(invalid-name-offset)"; | |
582 | } | |
583 | ||
23127b33 MKL |
584 | const char *btf_name_by_offset(const struct btf *btf, u32 offset) |
585 | { | |
586 | if (offset < btf->hdr.str_len) | |
587 | return &btf->strings[offset]; | |
588 | ||
589 | return NULL; | |
590 | } | |
591 | ||
838e9690 | 592 | const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id) |
eb3f595d MKL |
593 | { |
594 | if (type_id > btf->nr_types) | |
595 | return NULL; | |
596 | ||
597 | return btf->types[type_id]; | |
598 | } | |
599 | ||
4ef5f574 MKL |
600 | /* |
601 | * Regular int is not a bit field and it must be either | |
b1e8818c | 602 | * u8/u16/u32/u64 or __int128. |
4ef5f574 MKL |
603 | */ |
604 | static bool btf_type_int_is_regular(const struct btf_type *t) | |
605 | { | |
36fc3c8c | 606 | u8 nr_bits, nr_bytes; |
4ef5f574 MKL |
607 | u32 int_data; |
608 | ||
609 | int_data = btf_type_int(t); | |
610 | nr_bits = BTF_INT_BITS(int_data); | |
611 | nr_bytes = BITS_ROUNDUP_BYTES(nr_bits); | |
612 | if (BITS_PER_BYTE_MASKED(nr_bits) || | |
613 | BTF_INT_OFFSET(int_data) || | |
614 | (nr_bytes != sizeof(u8) && nr_bytes != sizeof(u16) && | |
b1e8818c YS |
615 | nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64) && |
616 | nr_bytes != (2 * sizeof(u64)))) { | |
4ef5f574 MKL |
617 | return false; |
618 | } | |
619 | ||
620 | return true; | |
621 | } | |
622 | ||
9a1126b6 | 623 | /* |
ffa0c1cf YS |
624 | * Check that given struct member is a regular int with expected |
625 | * offset and size. | |
9a1126b6 | 626 | */ |
ffa0c1cf YS |
627 | bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s, |
628 | const struct btf_member *m, | |
629 | u32 expected_offset, u32 expected_size) | |
9a1126b6 | 630 | { |
ffa0c1cf YS |
631 | const struct btf_type *t; |
632 | u32 id, int_data; | |
633 | u8 nr_bits; | |
9a1126b6 | 634 | |
ffa0c1cf YS |
635 | id = m->type; |
636 | t = btf_type_id_size(btf, &id, NULL); | |
637 | if (!t || !btf_type_is_int(t)) | |
9a1126b6 RG |
638 | return false; |
639 | ||
640 | int_data = btf_type_int(t); | |
641 | nr_bits = BTF_INT_BITS(int_data); | |
ffa0c1cf YS |
642 | if (btf_type_kflag(s)) { |
643 | u32 bitfield_size = BTF_MEMBER_BITFIELD_SIZE(m->offset); | |
644 | u32 bit_offset = BTF_MEMBER_BIT_OFFSET(m->offset); | |
645 | ||
646 | /* if kflag set, int should be a regular int and | |
647 | * bit offset should be at byte boundary. | |
648 | */ | |
649 | return !bitfield_size && | |
650 | BITS_ROUNDUP_BYTES(bit_offset) == expected_offset && | |
651 | BITS_ROUNDUP_BYTES(nr_bits) == expected_size; | |
652 | } | |
653 | ||
654 | if (BTF_INT_OFFSET(int_data) || | |
655 | BITS_PER_BYTE_MASKED(m->offset) || | |
656 | BITS_ROUNDUP_BYTES(m->offset) != expected_offset || | |
657 | BITS_PER_BYTE_MASKED(nr_bits) || | |
658 | BITS_ROUNDUP_BYTES(nr_bits) != expected_size) | |
9a1126b6 RG |
659 | return false; |
660 | ||
661 | return true; | |
662 | } | |
663 | ||
69b693f0 MKL |
664 | __printf(2, 3) static void __btf_verifier_log(struct bpf_verifier_log *log, |
665 | const char *fmt, ...) | |
666 | { | |
667 | va_list args; | |
668 | ||
669 | va_start(args, fmt); | |
670 | bpf_verifier_vlog(log, fmt, args); | |
671 | va_end(args); | |
672 | } | |
673 | ||
674 | __printf(2, 3) static void btf_verifier_log(struct btf_verifier_env *env, | |
675 | const char *fmt, ...) | |
676 | { | |
677 | struct bpf_verifier_log *log = &env->log; | |
678 | va_list args; | |
679 | ||
680 | if (!bpf_verifier_log_needed(log)) | |
681 | return; | |
682 | ||
683 | va_start(args, fmt); | |
684 | bpf_verifier_vlog(log, fmt, args); | |
685 | va_end(args); | |
686 | } | |
687 | ||
688 | __printf(4, 5) static void __btf_verifier_log_type(struct btf_verifier_env *env, | |
689 | const struct btf_type *t, | |
690 | bool log_details, | |
691 | const char *fmt, ...) | |
692 | { | |
693 | struct bpf_verifier_log *log = &env->log; | |
694 | u8 kind = BTF_INFO_KIND(t->info); | |
695 | struct btf *btf = env->btf; | |
696 | va_list args; | |
697 | ||
698 | if (!bpf_verifier_log_needed(log)) | |
699 | return; | |
700 | ||
701 | __btf_verifier_log(log, "[%u] %s %s%s", | |
702 | env->log_type_id, | |
703 | btf_kind_str[kind], | |
23127b33 | 704 | __btf_name_by_offset(btf, t->name_off), |
69b693f0 MKL |
705 | log_details ? " " : ""); |
706 | ||
707 | if (log_details) | |
708 | btf_type_ops(t)->log_details(env, t); | |
709 | ||
710 | if (fmt && *fmt) { | |
711 | __btf_verifier_log(log, " "); | |
712 | va_start(args, fmt); | |
713 | bpf_verifier_vlog(log, fmt, args); | |
714 | va_end(args); | |
715 | } | |
716 | ||
717 | __btf_verifier_log(log, "\n"); | |
718 | } | |
719 | ||
720 | #define btf_verifier_log_type(env, t, ...) \ | |
721 | __btf_verifier_log_type((env), (t), true, __VA_ARGS__) | |
722 | #define btf_verifier_log_basic(env, t, ...) \ | |
723 | __btf_verifier_log_type((env), (t), false, __VA_ARGS__) | |
724 | ||
725 | __printf(4, 5) | |
726 | static void btf_verifier_log_member(struct btf_verifier_env *env, | |
727 | const struct btf_type *struct_type, | |
728 | const struct btf_member *member, | |
729 | const char *fmt, ...) | |
730 | { | |
731 | struct bpf_verifier_log *log = &env->log; | |
732 | struct btf *btf = env->btf; | |
733 | va_list args; | |
734 | ||
735 | if (!bpf_verifier_log_needed(log)) | |
736 | return; | |
737 | ||
eb3f595d MKL |
738 | /* The CHECK_META phase already did a btf dump. |
739 | * | |
740 | * If member is logged again, it must hit an error in | |
741 | * parsing this member. It is useful to print out which | |
742 | * struct this member belongs to. | |
743 | */ | |
744 | if (env->phase != CHECK_META) | |
745 | btf_verifier_log_type(env, struct_type, NULL); | |
746 | ||
9d5f9f70 YS |
747 | if (btf_type_kflag(struct_type)) |
748 | __btf_verifier_log(log, | |
749 | "\t%s type_id=%u bitfield_size=%u bits_offset=%u", | |
750 | __btf_name_by_offset(btf, member->name_off), | |
751 | member->type, | |
752 | BTF_MEMBER_BITFIELD_SIZE(member->offset), | |
753 | BTF_MEMBER_BIT_OFFSET(member->offset)); | |
754 | else | |
755 | __btf_verifier_log(log, "\t%s type_id=%u bits_offset=%u", | |
756 | __btf_name_by_offset(btf, member->name_off), | |
757 | member->type, member->offset); | |
69b693f0 MKL |
758 | |
759 | if (fmt && *fmt) { | |
760 | __btf_verifier_log(log, " "); | |
761 | va_start(args, fmt); | |
762 | bpf_verifier_vlog(log, fmt, args); | |
763 | va_end(args); | |
764 | } | |
765 | ||
766 | __btf_verifier_log(log, "\n"); | |
767 | } | |
768 | ||
1dc92851 DB |
769 | __printf(4, 5) |
770 | static void btf_verifier_log_vsi(struct btf_verifier_env *env, | |
771 | const struct btf_type *datasec_type, | |
772 | const struct btf_var_secinfo *vsi, | |
773 | const char *fmt, ...) | |
774 | { | |
775 | struct bpf_verifier_log *log = &env->log; | |
776 | va_list args; | |
777 | ||
778 | if (!bpf_verifier_log_needed(log)) | |
779 | return; | |
780 | if (env->phase != CHECK_META) | |
781 | btf_verifier_log_type(env, datasec_type, NULL); | |
782 | ||
783 | __btf_verifier_log(log, "\t type_id=%u offset=%u size=%u", | |
784 | vsi->type, vsi->offset, vsi->size); | |
785 | if (fmt && *fmt) { | |
786 | __btf_verifier_log(log, " "); | |
787 | va_start(args, fmt); | |
788 | bpf_verifier_vlog(log, fmt, args); | |
789 | va_end(args); | |
790 | } | |
791 | ||
792 | __btf_verifier_log(log, "\n"); | |
793 | } | |
794 | ||
f80442a4 MKL |
795 | static void btf_verifier_log_hdr(struct btf_verifier_env *env, |
796 | u32 btf_data_size) | |
69b693f0 MKL |
797 | { |
798 | struct bpf_verifier_log *log = &env->log; | |
799 | const struct btf *btf = env->btf; | |
800 | const struct btf_header *hdr; | |
801 | ||
802 | if (!bpf_verifier_log_needed(log)) | |
803 | return; | |
804 | ||
f80442a4 | 805 | hdr = &btf->hdr; |
69b693f0 MKL |
806 | __btf_verifier_log(log, "magic: 0x%x\n", hdr->magic); |
807 | __btf_verifier_log(log, "version: %u\n", hdr->version); | |
808 | __btf_verifier_log(log, "flags: 0x%x\n", hdr->flags); | |
f80442a4 | 809 | __btf_verifier_log(log, "hdr_len: %u\n", hdr->hdr_len); |
69b693f0 | 810 | __btf_verifier_log(log, "type_off: %u\n", hdr->type_off); |
f80442a4 | 811 | __btf_verifier_log(log, "type_len: %u\n", hdr->type_len); |
69b693f0 MKL |
812 | __btf_verifier_log(log, "str_off: %u\n", hdr->str_off); |
813 | __btf_verifier_log(log, "str_len: %u\n", hdr->str_len); | |
f80442a4 | 814 | __btf_verifier_log(log, "btf_total_size: %u\n", btf_data_size); |
69b693f0 MKL |
815 | } |
816 | ||
817 | static int btf_add_type(struct btf_verifier_env *env, struct btf_type *t) | |
818 | { | |
819 | struct btf *btf = env->btf; | |
820 | ||
821 | /* < 2 because +1 for btf_void which is always in btf->types[0]. | |
822 | * btf_void is not accounted in btf->nr_types because btf_void | |
823 | * does not come from the BTF file. | |
824 | */ | |
825 | if (btf->types_size - btf->nr_types < 2) { | |
826 | /* Expand 'types' array */ | |
827 | ||
828 | struct btf_type **new_types; | |
829 | u32 expand_by, new_size; | |
830 | ||
aea2f7b8 | 831 | if (btf->types_size == BTF_MAX_TYPE) { |
69b693f0 MKL |
832 | btf_verifier_log(env, "Exceeded max num of types"); |
833 | return -E2BIG; | |
834 | } | |
835 | ||
836 | expand_by = max_t(u32, btf->types_size >> 2, 16); | |
aea2f7b8 | 837 | new_size = min_t(u32, BTF_MAX_TYPE, |
69b693f0 MKL |
838 | btf->types_size + expand_by); |
839 | ||
778e1cdd | 840 | new_types = kvcalloc(new_size, sizeof(*new_types), |
69b693f0 MKL |
841 | GFP_KERNEL | __GFP_NOWARN); |
842 | if (!new_types) | |
843 | return -ENOMEM; | |
844 | ||
845 | if (btf->nr_types == 0) | |
846 | new_types[0] = &btf_void; | |
847 | else | |
848 | memcpy(new_types, btf->types, | |
849 | sizeof(*btf->types) * (btf->nr_types + 1)); | |
850 | ||
851 | kvfree(btf->types); | |
852 | btf->types = new_types; | |
853 | btf->types_size = new_size; | |
854 | } | |
855 | ||
856 | btf->types[++(btf->nr_types)] = t; | |
857 | ||
858 | return 0; | |
859 | } | |
860 | ||
78958fca MKL |
861 | static int btf_alloc_id(struct btf *btf) |
862 | { | |
863 | int id; | |
864 | ||
865 | idr_preload(GFP_KERNEL); | |
866 | spin_lock_bh(&btf_idr_lock); | |
867 | id = idr_alloc_cyclic(&btf_idr, btf, 1, INT_MAX, GFP_ATOMIC); | |
868 | if (id > 0) | |
869 | btf->id = id; | |
870 | spin_unlock_bh(&btf_idr_lock); | |
871 | idr_preload_end(); | |
872 | ||
873 | if (WARN_ON_ONCE(!id)) | |
874 | return -ENOSPC; | |
875 | ||
876 | return id > 0 ? 0 : id; | |
877 | } | |
878 | ||
879 | static void btf_free_id(struct btf *btf) | |
880 | { | |
881 | unsigned long flags; | |
882 | ||
883 | /* | |
884 | * In map-in-map, calling map_delete_elem() on outer | |
885 | * map will call bpf_map_put on the inner map. | |
886 | * It will then eventually call btf_free_id() | |
887 | * on the inner map. Some of the map_delete_elem() | |
888 | * implementation may have irq disabled, so | |
889 | * we need to use the _irqsave() version instead | |
890 | * of the _bh() version. | |
891 | */ | |
892 | spin_lock_irqsave(&btf_idr_lock, flags); | |
893 | idr_remove(&btf_idr, btf->id); | |
894 | spin_unlock_irqrestore(&btf_idr_lock, flags); | |
895 | } | |
896 | ||
69b693f0 MKL |
897 | static void btf_free(struct btf *btf) |
898 | { | |
899 | kvfree(btf->types); | |
eb3f595d MKL |
900 | kvfree(btf->resolved_sizes); |
901 | kvfree(btf->resolved_ids); | |
69b693f0 MKL |
902 | kvfree(btf->data); |
903 | kfree(btf); | |
904 | } | |
905 | ||
78958fca | 906 | static void btf_free_rcu(struct rcu_head *rcu) |
f56a653c | 907 | { |
78958fca MKL |
908 | struct btf *btf = container_of(rcu, struct btf, rcu); |
909 | ||
910 | btf_free(btf); | |
f56a653c MKL |
911 | } |
912 | ||
913 | void btf_put(struct btf *btf) | |
914 | { | |
78958fca MKL |
915 | if (btf && refcount_dec_and_test(&btf->refcnt)) { |
916 | btf_free_id(btf); | |
917 | call_rcu(&btf->rcu, btf_free_rcu); | |
918 | } | |
f56a653c MKL |
919 | } |
920 | ||
eb3f595d MKL |
921 | static int env_resolve_init(struct btf_verifier_env *env) |
922 | { | |
923 | struct btf *btf = env->btf; | |
924 | u32 nr_types = btf->nr_types; | |
925 | u32 *resolved_sizes = NULL; | |
926 | u32 *resolved_ids = NULL; | |
927 | u8 *visit_states = NULL; | |
928 | ||
929 | /* +1 for btf_void */ | |
778e1cdd | 930 | resolved_sizes = kvcalloc(nr_types + 1, sizeof(*resolved_sizes), |
eb3f595d MKL |
931 | GFP_KERNEL | __GFP_NOWARN); |
932 | if (!resolved_sizes) | |
933 | goto nomem; | |
934 | ||
778e1cdd | 935 | resolved_ids = kvcalloc(nr_types + 1, sizeof(*resolved_ids), |
eb3f595d MKL |
936 | GFP_KERNEL | __GFP_NOWARN); |
937 | if (!resolved_ids) | |
938 | goto nomem; | |
939 | ||
778e1cdd | 940 | visit_states = kvcalloc(nr_types + 1, sizeof(*visit_states), |
eb3f595d MKL |
941 | GFP_KERNEL | __GFP_NOWARN); |
942 | if (!visit_states) | |
943 | goto nomem; | |
944 | ||
945 | btf->resolved_sizes = resolved_sizes; | |
946 | btf->resolved_ids = resolved_ids; | |
947 | env->visit_states = visit_states; | |
948 | ||
949 | return 0; | |
950 | ||
951 | nomem: | |
952 | kvfree(resolved_sizes); | |
953 | kvfree(resolved_ids); | |
954 | kvfree(visit_states); | |
955 | return -ENOMEM; | |
956 | } | |
957 | ||
69b693f0 MKL |
958 | static void btf_verifier_env_free(struct btf_verifier_env *env) |
959 | { | |
eb3f595d | 960 | kvfree(env->visit_states); |
69b693f0 MKL |
961 | kfree(env); |
962 | } | |
963 | ||
eb3f595d MKL |
964 | static bool env_type_is_resolve_sink(const struct btf_verifier_env *env, |
965 | const struct btf_type *next_type) | |
966 | { | |
967 | switch (env->resolve_mode) { | |
968 | case RESOLVE_TBD: | |
969 | /* int, enum or void is a sink */ | |
970 | return !btf_type_needs_resolve(next_type); | |
971 | case RESOLVE_PTR: | |
2667a262 MKL |
972 | /* int, enum, void, struct, array, func or func_proto is a sink |
973 | * for ptr | |
974 | */ | |
eb3f595d MKL |
975 | return !btf_type_is_modifier(next_type) && |
976 | !btf_type_is_ptr(next_type); | |
977 | case RESOLVE_STRUCT_OR_ARRAY: | |
2667a262 MKL |
978 | /* int, enum, void, ptr, func or func_proto is a sink |
979 | * for struct and array | |
980 | */ | |
eb3f595d MKL |
981 | return !btf_type_is_modifier(next_type) && |
982 | !btf_type_is_array(next_type) && | |
983 | !btf_type_is_struct(next_type); | |
984 | default: | |
53c8036c | 985 | BUG(); |
eb3f595d MKL |
986 | } |
987 | } | |
988 | ||
989 | static bool env_type_is_resolved(const struct btf_verifier_env *env, | |
990 | u32 type_id) | |
991 | { | |
992 | return env->visit_states[type_id] == RESOLVED; | |
993 | } | |
994 | ||
995 | static int env_stack_push(struct btf_verifier_env *env, | |
996 | const struct btf_type *t, u32 type_id) | |
997 | { | |
998 | struct resolve_vertex *v; | |
999 | ||
1000 | if (env->top_stack == MAX_RESOLVE_DEPTH) | |
1001 | return -E2BIG; | |
1002 | ||
1003 | if (env->visit_states[type_id] != NOT_VISITED) | |
1004 | return -EEXIST; | |
1005 | ||
1006 | env->visit_states[type_id] = VISITED; | |
1007 | ||
1008 | v = &env->stack[env->top_stack++]; | |
1009 | v->t = t; | |
1010 | v->type_id = type_id; | |
1011 | v->next_member = 0; | |
1012 | ||
1013 | if (env->resolve_mode == RESOLVE_TBD) { | |
1014 | if (btf_type_is_ptr(t)) | |
1015 | env->resolve_mode = RESOLVE_PTR; | |
1016 | else if (btf_type_is_struct(t) || btf_type_is_array(t)) | |
1017 | env->resolve_mode = RESOLVE_STRUCT_OR_ARRAY; | |
1018 | } | |
1019 | ||
1020 | return 0; | |
1021 | } | |
1022 | ||
1023 | static void env_stack_set_next_member(struct btf_verifier_env *env, | |
1024 | u16 next_member) | |
1025 | { | |
1026 | env->stack[env->top_stack - 1].next_member = next_member; | |
1027 | } | |
1028 | ||
1029 | static void env_stack_pop_resolved(struct btf_verifier_env *env, | |
1030 | u32 resolved_type_id, | |
1031 | u32 resolved_size) | |
1032 | { | |
1033 | u32 type_id = env->stack[--(env->top_stack)].type_id; | |
1034 | struct btf *btf = env->btf; | |
1035 | ||
1036 | btf->resolved_sizes[type_id] = resolved_size; | |
1037 | btf->resolved_ids[type_id] = resolved_type_id; | |
1038 | env->visit_states[type_id] = RESOLVED; | |
1039 | } | |
1040 | ||
1041 | static const struct resolve_vertex *env_stack_peak(struct btf_verifier_env *env) | |
1042 | { | |
1043 | return env->top_stack ? &env->stack[env->top_stack - 1] : NULL; | |
1044 | } | |
1045 | ||
1046 | /* The input param "type_id" must point to a needs_resolve type */ | |
1047 | static const struct btf_type *btf_type_id_resolve(const struct btf *btf, | |
1048 | u32 *type_id) | |
1049 | { | |
1050 | *type_id = btf->resolved_ids[*type_id]; | |
1051 | return btf_type_by_id(btf, *type_id); | |
1052 | } | |
1053 | ||
1054 | const struct btf_type *btf_type_id_size(const struct btf *btf, | |
1055 | u32 *type_id, u32 *ret_size) | |
1056 | { | |
1057 | const struct btf_type *size_type; | |
1058 | u32 size_type_id = *type_id; | |
1059 | u32 size = 0; | |
1060 | ||
1061 | size_type = btf_type_by_id(btf, size_type_id); | |
b47a0bd2 | 1062 | if (btf_type_nosize_or_null(size_type)) |
eb3f595d MKL |
1063 | return NULL; |
1064 | ||
1065 | if (btf_type_has_size(size_type)) { | |
1066 | size = size_type->size; | |
1067 | } else if (btf_type_is_array(size_type)) { | |
1068 | size = btf->resolved_sizes[size_type_id]; | |
1069 | } else if (btf_type_is_ptr(size_type)) { | |
1070 | size = sizeof(void *); | |
1071 | } else { | |
1dc92851 DB |
1072 | if (WARN_ON_ONCE(!btf_type_is_modifier(size_type) && |
1073 | !btf_type_is_var(size_type))) | |
eb3f595d MKL |
1074 | return NULL; |
1075 | ||
1076 | size = btf->resolved_sizes[size_type_id]; | |
1077 | size_type_id = btf->resolved_ids[size_type_id]; | |
1078 | size_type = btf_type_by_id(btf, size_type_id); | |
b47a0bd2 | 1079 | if (btf_type_nosize_or_null(size_type)) |
eb3f595d MKL |
1080 | return NULL; |
1081 | } | |
1082 | ||
1083 | *type_id = size_type_id; | |
1084 | if (ret_size) | |
1085 | *ret_size = size; | |
1086 | ||
1087 | return size_type; | |
1088 | } | |
1089 | ||
179cde8c MKL |
1090 | static int btf_df_check_member(struct btf_verifier_env *env, |
1091 | const struct btf_type *struct_type, | |
1092 | const struct btf_member *member, | |
1093 | const struct btf_type *member_type) | |
1094 | { | |
1095 | btf_verifier_log_basic(env, struct_type, | |
1096 | "Unsupported check_member"); | |
1097 | return -EINVAL; | |
1098 | } | |
1099 | ||
9d5f9f70 YS |
1100 | static int btf_df_check_kflag_member(struct btf_verifier_env *env, |
1101 | const struct btf_type *struct_type, | |
1102 | const struct btf_member *member, | |
1103 | const struct btf_type *member_type) | |
1104 | { | |
1105 | btf_verifier_log_basic(env, struct_type, | |
1106 | "Unsupported check_kflag_member"); | |
1107 | return -EINVAL; | |
1108 | } | |
1109 | ||
1110 | /* Used for ptr, array and struct/union type members. | |
1111 | * int, enum and modifier types have their specific callback functions. | |
1112 | */ | |
1113 | static int btf_generic_check_kflag_member(struct btf_verifier_env *env, | |
1114 | const struct btf_type *struct_type, | |
1115 | const struct btf_member *member, | |
1116 | const struct btf_type *member_type) | |
1117 | { | |
1118 | if (BTF_MEMBER_BITFIELD_SIZE(member->offset)) { | |
1119 | btf_verifier_log_member(env, struct_type, member, | |
1120 | "Invalid member bitfield_size"); | |
1121 | return -EINVAL; | |
1122 | } | |
1123 | ||
1124 | /* bitfield size is 0, so member->offset represents bit offset only. | |
1125 | * It is safe to call non kflag check_member variants. | |
1126 | */ | |
1127 | return btf_type_ops(member_type)->check_member(env, struct_type, | |
1128 | member, | |
1129 | member_type); | |
1130 | } | |
1131 | ||
eb3f595d MKL |
1132 | static int btf_df_resolve(struct btf_verifier_env *env, |
1133 | const struct resolve_vertex *v) | |
1134 | { | |
1135 | btf_verifier_log_basic(env, v->t, "Unsupported resolve"); | |
1136 | return -EINVAL; | |
1137 | } | |
1138 | ||
b00b8dae MKL |
1139 | static void btf_df_seq_show(const struct btf *btf, const struct btf_type *t, |
1140 | u32 type_id, void *data, u8 bits_offsets, | |
1141 | struct seq_file *m) | |
1142 | { | |
1143 | seq_printf(m, "<unsupported kind:%u>", BTF_INFO_KIND(t->info)); | |
1144 | } | |
1145 | ||
179cde8c MKL |
1146 | static int btf_int_check_member(struct btf_verifier_env *env, |
1147 | const struct btf_type *struct_type, | |
1148 | const struct btf_member *member, | |
1149 | const struct btf_type *member_type) | |
1150 | { | |
1151 | u32 int_data = btf_type_int(member_type); | |
1152 | u32 struct_bits_off = member->offset; | |
1153 | u32 struct_size = struct_type->size; | |
1154 | u32 nr_copy_bits; | |
1155 | u32 bytes_offset; | |
1156 | ||
1157 | if (U32_MAX - struct_bits_off < BTF_INT_OFFSET(int_data)) { | |
1158 | btf_verifier_log_member(env, struct_type, member, | |
1159 | "bits_offset exceeds U32_MAX"); | |
1160 | return -EINVAL; | |
1161 | } | |
1162 | ||
1163 | struct_bits_off += BTF_INT_OFFSET(int_data); | |
1164 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
1165 | nr_copy_bits = BTF_INT_BITS(int_data) + | |
1166 | BITS_PER_BYTE_MASKED(struct_bits_off); | |
1167 | ||
b1e8818c | 1168 | if (nr_copy_bits > BITS_PER_U128) { |
179cde8c | 1169 | btf_verifier_log_member(env, struct_type, member, |
b1e8818c | 1170 | "nr_copy_bits exceeds 128"); |
179cde8c MKL |
1171 | return -EINVAL; |
1172 | } | |
1173 | ||
1174 | if (struct_size < bytes_offset || | |
1175 | struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) { | |
1176 | btf_verifier_log_member(env, struct_type, member, | |
1177 | "Member exceeds struct_size"); | |
1178 | return -EINVAL; | |
1179 | } | |
1180 | ||
1181 | return 0; | |
1182 | } | |
1183 | ||
9d5f9f70 YS |
1184 | static int btf_int_check_kflag_member(struct btf_verifier_env *env, |
1185 | const struct btf_type *struct_type, | |
1186 | const struct btf_member *member, | |
1187 | const struct btf_type *member_type) | |
1188 | { | |
1189 | u32 struct_bits_off, nr_bits, nr_int_data_bits, bytes_offset; | |
1190 | u32 int_data = btf_type_int(member_type); | |
1191 | u32 struct_size = struct_type->size; | |
1192 | u32 nr_copy_bits; | |
1193 | ||
1194 | /* a regular int type is required for the kflag int member */ | |
1195 | if (!btf_type_int_is_regular(member_type)) { | |
1196 | btf_verifier_log_member(env, struct_type, member, | |
1197 | "Invalid member base type"); | |
1198 | return -EINVAL; | |
1199 | } | |
1200 | ||
1201 | /* check sanity of bitfield size */ | |
1202 | nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset); | |
1203 | struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset); | |
1204 | nr_int_data_bits = BTF_INT_BITS(int_data); | |
1205 | if (!nr_bits) { | |
1206 | /* Not a bitfield member, member offset must be at byte | |
1207 | * boundary. | |
1208 | */ | |
1209 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
1210 | btf_verifier_log_member(env, struct_type, member, | |
1211 | "Invalid member offset"); | |
1212 | return -EINVAL; | |
1213 | } | |
1214 | ||
1215 | nr_bits = nr_int_data_bits; | |
1216 | } else if (nr_bits > nr_int_data_bits) { | |
1217 | btf_verifier_log_member(env, struct_type, member, | |
1218 | "Invalid member bitfield_size"); | |
1219 | return -EINVAL; | |
1220 | } | |
1221 | ||
1222 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
1223 | nr_copy_bits = nr_bits + BITS_PER_BYTE_MASKED(struct_bits_off); | |
b1e8818c | 1224 | if (nr_copy_bits > BITS_PER_U128) { |
9d5f9f70 | 1225 | btf_verifier_log_member(env, struct_type, member, |
b1e8818c | 1226 | "nr_copy_bits exceeds 128"); |
9d5f9f70 YS |
1227 | return -EINVAL; |
1228 | } | |
1229 | ||
1230 | if (struct_size < bytes_offset || | |
1231 | struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) { | |
1232 | btf_verifier_log_member(env, struct_type, member, | |
1233 | "Member exceeds struct_size"); | |
1234 | return -EINVAL; | |
1235 | } | |
1236 | ||
1237 | return 0; | |
1238 | } | |
1239 | ||
69b693f0 MKL |
1240 | static s32 btf_int_check_meta(struct btf_verifier_env *env, |
1241 | const struct btf_type *t, | |
1242 | u32 meta_left) | |
1243 | { | |
1244 | u32 int_data, nr_bits, meta_needed = sizeof(int_data); | |
1245 | u16 encoding; | |
1246 | ||
1247 | if (meta_left < meta_needed) { | |
1248 | btf_verifier_log_basic(env, t, | |
1249 | "meta_left:%u meta_needed:%u", | |
1250 | meta_left, meta_needed); | |
1251 | return -EINVAL; | |
1252 | } | |
1253 | ||
1254 | if (btf_type_vlen(t)) { | |
1255 | btf_verifier_log_type(env, t, "vlen != 0"); | |
1256 | return -EINVAL; | |
1257 | } | |
1258 | ||
9d5f9f70 YS |
1259 | if (btf_type_kflag(t)) { |
1260 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
1261 | return -EINVAL; | |
1262 | } | |
1263 | ||
69b693f0 | 1264 | int_data = btf_type_int(t); |
aea2f7b8 MKL |
1265 | if (int_data & ~BTF_INT_MASK) { |
1266 | btf_verifier_log_basic(env, t, "Invalid int_data:%x", | |
1267 | int_data); | |
1268 | return -EINVAL; | |
1269 | } | |
1270 | ||
69b693f0 MKL |
1271 | nr_bits = BTF_INT_BITS(int_data) + BTF_INT_OFFSET(int_data); |
1272 | ||
b1e8818c | 1273 | if (nr_bits > BITS_PER_U128) { |
69b693f0 | 1274 | btf_verifier_log_type(env, t, "nr_bits exceeds %zu", |
b1e8818c | 1275 | BITS_PER_U128); |
69b693f0 MKL |
1276 | return -EINVAL; |
1277 | } | |
1278 | ||
1279 | if (BITS_ROUNDUP_BYTES(nr_bits) > t->size) { | |
1280 | btf_verifier_log_type(env, t, "nr_bits exceeds type_size"); | |
1281 | return -EINVAL; | |
1282 | } | |
1283 | ||
aea2f7b8 MKL |
1284 | /* |
1285 | * Only one of the encoding bits is allowed and it | |
1286 | * should be sufficient for the pretty print purpose (i.e. decoding). | |
1287 | * Multiple bits can be allowed later if it is found | |
1288 | * to be insufficient. | |
1289 | */ | |
69b693f0 MKL |
1290 | encoding = BTF_INT_ENCODING(int_data); |
1291 | if (encoding && | |
1292 | encoding != BTF_INT_SIGNED && | |
1293 | encoding != BTF_INT_CHAR && | |
aea2f7b8 | 1294 | encoding != BTF_INT_BOOL) { |
69b693f0 MKL |
1295 | btf_verifier_log_type(env, t, "Unsupported encoding"); |
1296 | return -ENOTSUPP; | |
1297 | } | |
1298 | ||
1299 | btf_verifier_log_type(env, t, NULL); | |
1300 | ||
1301 | return meta_needed; | |
1302 | } | |
1303 | ||
1304 | static void btf_int_log(struct btf_verifier_env *env, | |
1305 | const struct btf_type *t) | |
1306 | { | |
1307 | int int_data = btf_type_int(t); | |
1308 | ||
1309 | btf_verifier_log(env, | |
1310 | "size=%u bits_offset=%u nr_bits=%u encoding=%s", | |
1311 | t->size, BTF_INT_OFFSET(int_data), | |
1312 | BTF_INT_BITS(int_data), | |
1313 | btf_int_encoding_str(BTF_INT_ENCODING(int_data))); | |
1314 | } | |
1315 | ||
b1e8818c YS |
1316 | static void btf_int128_print(struct seq_file *m, void *data) |
1317 | { | |
1318 | /* data points to a __int128 number. | |
1319 | * Suppose | |
1320 | * int128_num = *(__int128 *)data; | |
1321 | * The below formulas shows what upper_num and lower_num represents: | |
1322 | * upper_num = int128_num >> 64; | |
1323 | * lower_num = int128_num & 0xffffffffFFFFFFFFULL; | |
1324 | */ | |
1325 | u64 upper_num, lower_num; | |
1326 | ||
1327 | #ifdef __BIG_ENDIAN_BITFIELD | |
1328 | upper_num = *(u64 *)data; | |
1329 | lower_num = *(u64 *)(data + 8); | |
1330 | #else | |
1331 | upper_num = *(u64 *)(data + 8); | |
1332 | lower_num = *(u64 *)data; | |
1333 | #endif | |
1334 | if (upper_num == 0) | |
1335 | seq_printf(m, "0x%llx", lower_num); | |
1336 | else | |
1337 | seq_printf(m, "0x%llx%016llx", upper_num, lower_num); | |
1338 | } | |
1339 | ||
1340 | static void btf_int128_shift(u64 *print_num, u16 left_shift_bits, | |
1341 | u16 right_shift_bits) | |
1342 | { | |
1343 | u64 upper_num, lower_num; | |
1344 | ||
1345 | #ifdef __BIG_ENDIAN_BITFIELD | |
1346 | upper_num = print_num[0]; | |
1347 | lower_num = print_num[1]; | |
1348 | #else | |
1349 | upper_num = print_num[1]; | |
1350 | lower_num = print_num[0]; | |
1351 | #endif | |
1352 | ||
1353 | /* shake out un-needed bits by shift/or operations */ | |
1354 | if (left_shift_bits >= 64) { | |
1355 | upper_num = lower_num << (left_shift_bits - 64); | |
1356 | lower_num = 0; | |
1357 | } else { | |
1358 | upper_num = (upper_num << left_shift_bits) | | |
1359 | (lower_num >> (64 - left_shift_bits)); | |
1360 | lower_num = lower_num << left_shift_bits; | |
1361 | } | |
1362 | ||
1363 | if (right_shift_bits >= 64) { | |
1364 | lower_num = upper_num >> (right_shift_bits - 64); | |
1365 | upper_num = 0; | |
1366 | } else { | |
1367 | lower_num = (lower_num >> right_shift_bits) | | |
1368 | (upper_num << (64 - right_shift_bits)); | |
1369 | upper_num = upper_num >> right_shift_bits; | |
1370 | } | |
1371 | ||
1372 | #ifdef __BIG_ENDIAN_BITFIELD | |
1373 | print_num[0] = upper_num; | |
1374 | print_num[1] = lower_num; | |
1375 | #else | |
1376 | print_num[0] = lower_num; | |
1377 | print_num[1] = upper_num; | |
1378 | #endif | |
1379 | } | |
1380 | ||
f97be3ab YS |
1381 | static void btf_bitfield_seq_show(void *data, u8 bits_offset, |
1382 | u8 nr_bits, struct seq_file *m) | |
b00b8dae | 1383 | { |
b65f370d | 1384 | u16 left_shift_bits, right_shift_bits; |
36fc3c8c MKL |
1385 | u8 nr_copy_bytes; |
1386 | u8 nr_copy_bits; | |
b1e8818c | 1387 | u64 print_num[2] = {}; |
b00b8dae | 1388 | |
b00b8dae MKL |
1389 | nr_copy_bits = nr_bits + bits_offset; |
1390 | nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits); | |
1391 | ||
b1e8818c | 1392 | memcpy(print_num, data, nr_copy_bytes); |
b00b8dae | 1393 | |
b65f370d OK |
1394 | #ifdef __BIG_ENDIAN_BITFIELD |
1395 | left_shift_bits = bits_offset; | |
1396 | #else | |
b1e8818c | 1397 | left_shift_bits = BITS_PER_U128 - nr_copy_bits; |
b65f370d | 1398 | #endif |
b1e8818c | 1399 | right_shift_bits = BITS_PER_U128 - nr_bits; |
b00b8dae | 1400 | |
b1e8818c YS |
1401 | btf_int128_shift(print_num, left_shift_bits, right_shift_bits); |
1402 | btf_int128_print(m, print_num); | |
b00b8dae MKL |
1403 | } |
1404 | ||
9d5f9f70 | 1405 | |
f97be3ab YS |
1406 | static void btf_int_bits_seq_show(const struct btf *btf, |
1407 | const struct btf_type *t, | |
1408 | void *data, u8 bits_offset, | |
1409 | struct seq_file *m) | |
1410 | { | |
1411 | u32 int_data = btf_type_int(t); | |
1412 | u8 nr_bits = BTF_INT_BITS(int_data); | |
1413 | u8 total_bits_offset; | |
1414 | ||
1415 | /* | |
1416 | * bits_offset is at most 7. | |
b1e8818c | 1417 | * BTF_INT_OFFSET() cannot exceed 128 bits. |
f97be3ab YS |
1418 | */ |
1419 | total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data); | |
17e3ac81 YS |
1420 | data += BITS_ROUNDDOWN_BYTES(total_bits_offset); |
1421 | bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset); | |
1422 | btf_bitfield_seq_show(data, bits_offset, nr_bits, m); | |
f97be3ab YS |
1423 | } |
1424 | ||
b00b8dae MKL |
1425 | static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t, |
1426 | u32 type_id, void *data, u8 bits_offset, | |
1427 | struct seq_file *m) | |
1428 | { | |
1429 | u32 int_data = btf_type_int(t); | |
1430 | u8 encoding = BTF_INT_ENCODING(int_data); | |
1431 | bool sign = encoding & BTF_INT_SIGNED; | |
36fc3c8c | 1432 | u8 nr_bits = BTF_INT_BITS(int_data); |
b00b8dae MKL |
1433 | |
1434 | if (bits_offset || BTF_INT_OFFSET(int_data) || | |
1435 | BITS_PER_BYTE_MASKED(nr_bits)) { | |
1436 | btf_int_bits_seq_show(btf, t, data, bits_offset, m); | |
1437 | return; | |
1438 | } | |
1439 | ||
1440 | switch (nr_bits) { | |
b1e8818c YS |
1441 | case 128: |
1442 | btf_int128_print(m, data); | |
1443 | break; | |
b00b8dae MKL |
1444 | case 64: |
1445 | if (sign) | |
1446 | seq_printf(m, "%lld", *(s64 *)data); | |
1447 | else | |
1448 | seq_printf(m, "%llu", *(u64 *)data); | |
1449 | break; | |
1450 | case 32: | |
1451 | if (sign) | |
1452 | seq_printf(m, "%d", *(s32 *)data); | |
1453 | else | |
1454 | seq_printf(m, "%u", *(u32 *)data); | |
1455 | break; | |
1456 | case 16: | |
1457 | if (sign) | |
1458 | seq_printf(m, "%d", *(s16 *)data); | |
1459 | else | |
1460 | seq_printf(m, "%u", *(u16 *)data); | |
1461 | break; | |
1462 | case 8: | |
1463 | if (sign) | |
1464 | seq_printf(m, "%d", *(s8 *)data); | |
1465 | else | |
1466 | seq_printf(m, "%u", *(u8 *)data); | |
1467 | break; | |
1468 | default: | |
1469 | btf_int_bits_seq_show(btf, t, data, bits_offset, m); | |
1470 | } | |
1471 | } | |
1472 | ||
69b693f0 MKL |
1473 | static const struct btf_kind_operations int_ops = { |
1474 | .check_meta = btf_int_check_meta, | |
eb3f595d | 1475 | .resolve = btf_df_resolve, |
179cde8c | 1476 | .check_member = btf_int_check_member, |
9d5f9f70 | 1477 | .check_kflag_member = btf_int_check_kflag_member, |
69b693f0 | 1478 | .log_details = btf_int_log, |
b00b8dae | 1479 | .seq_show = btf_int_seq_show, |
69b693f0 MKL |
1480 | }; |
1481 | ||
179cde8c MKL |
1482 | static int btf_modifier_check_member(struct btf_verifier_env *env, |
1483 | const struct btf_type *struct_type, | |
1484 | const struct btf_member *member, | |
1485 | const struct btf_type *member_type) | |
1486 | { | |
1487 | const struct btf_type *resolved_type; | |
1488 | u32 resolved_type_id = member->type; | |
1489 | struct btf_member resolved_member; | |
1490 | struct btf *btf = env->btf; | |
1491 | ||
1492 | resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL); | |
1493 | if (!resolved_type) { | |
1494 | btf_verifier_log_member(env, struct_type, member, | |
1495 | "Invalid member"); | |
1496 | return -EINVAL; | |
1497 | } | |
1498 | ||
1499 | resolved_member = *member; | |
1500 | resolved_member.type = resolved_type_id; | |
1501 | ||
1502 | return btf_type_ops(resolved_type)->check_member(env, struct_type, | |
1503 | &resolved_member, | |
1504 | resolved_type); | |
1505 | } | |
1506 | ||
9d5f9f70 YS |
1507 | static int btf_modifier_check_kflag_member(struct btf_verifier_env *env, |
1508 | const struct btf_type *struct_type, | |
1509 | const struct btf_member *member, | |
1510 | const struct btf_type *member_type) | |
1511 | { | |
1512 | const struct btf_type *resolved_type; | |
1513 | u32 resolved_type_id = member->type; | |
1514 | struct btf_member resolved_member; | |
1515 | struct btf *btf = env->btf; | |
1516 | ||
1517 | resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL); | |
1518 | if (!resolved_type) { | |
1519 | btf_verifier_log_member(env, struct_type, member, | |
1520 | "Invalid member"); | |
1521 | return -EINVAL; | |
1522 | } | |
1523 | ||
1524 | resolved_member = *member; | |
1525 | resolved_member.type = resolved_type_id; | |
1526 | ||
1527 | return btf_type_ops(resolved_type)->check_kflag_member(env, struct_type, | |
1528 | &resolved_member, | |
1529 | resolved_type); | |
1530 | } | |
1531 | ||
179cde8c MKL |
1532 | static int btf_ptr_check_member(struct btf_verifier_env *env, |
1533 | const struct btf_type *struct_type, | |
1534 | const struct btf_member *member, | |
1535 | const struct btf_type *member_type) | |
1536 | { | |
1537 | u32 struct_size, struct_bits_off, bytes_offset; | |
1538 | ||
1539 | struct_size = struct_type->size; | |
1540 | struct_bits_off = member->offset; | |
1541 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
1542 | ||
1543 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
1544 | btf_verifier_log_member(env, struct_type, member, | |
1545 | "Member is not byte aligned"); | |
1546 | return -EINVAL; | |
1547 | } | |
1548 | ||
1549 | if (struct_size - bytes_offset < sizeof(void *)) { | |
1550 | btf_verifier_log_member(env, struct_type, member, | |
1551 | "Member exceeds struct_size"); | |
1552 | return -EINVAL; | |
1553 | } | |
1554 | ||
1555 | return 0; | |
1556 | } | |
1557 | ||
69b693f0 MKL |
1558 | static int btf_ref_type_check_meta(struct btf_verifier_env *env, |
1559 | const struct btf_type *t, | |
1560 | u32 meta_left) | |
1561 | { | |
1562 | if (btf_type_vlen(t)) { | |
1563 | btf_verifier_log_type(env, t, "vlen != 0"); | |
1564 | return -EINVAL; | |
1565 | } | |
1566 | ||
9d5f9f70 YS |
1567 | if (btf_type_kflag(t)) { |
1568 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
1569 | return -EINVAL; | |
1570 | } | |
1571 | ||
aea2f7b8 | 1572 | if (!BTF_TYPE_ID_VALID(t->type)) { |
69b693f0 MKL |
1573 | btf_verifier_log_type(env, t, "Invalid type_id"); |
1574 | return -EINVAL; | |
1575 | } | |
1576 | ||
eb04bbb6 YS |
1577 | /* typedef type must have a valid name, and other ref types, |
1578 | * volatile, const, restrict, should have a null name. | |
1579 | */ | |
1580 | if (BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF) { | |
1581 | if (!t->name_off || | |
1582 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
1583 | btf_verifier_log_type(env, t, "Invalid name"); | |
1584 | return -EINVAL; | |
1585 | } | |
1586 | } else { | |
1587 | if (t->name_off) { | |
1588 | btf_verifier_log_type(env, t, "Invalid name"); | |
1589 | return -EINVAL; | |
1590 | } | |
1591 | } | |
1592 | ||
69b693f0 MKL |
1593 | btf_verifier_log_type(env, t, NULL); |
1594 | ||
1595 | return 0; | |
1596 | } | |
1597 | ||
eb3f595d MKL |
1598 | static int btf_modifier_resolve(struct btf_verifier_env *env, |
1599 | const struct resolve_vertex *v) | |
1600 | { | |
1601 | const struct btf_type *t = v->t; | |
1602 | const struct btf_type *next_type; | |
1603 | u32 next_type_id = t->type; | |
1604 | struct btf *btf = env->btf; | |
1605 | u32 next_type_size = 0; | |
1606 | ||
1607 | next_type = btf_type_by_id(btf, next_type_id); | |
1dc92851 | 1608 | if (!next_type || btf_type_is_resolve_source_only(next_type)) { |
eb3f595d MKL |
1609 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
1610 | return -EINVAL; | |
1611 | } | |
1612 | ||
eb3f595d MKL |
1613 | if (!env_type_is_resolve_sink(env, next_type) && |
1614 | !env_type_is_resolved(env, next_type_id)) | |
1615 | return env_stack_push(env, next_type, next_type_id); | |
1616 | ||
1617 | /* Figure out the resolved next_type_id with size. | |
1618 | * They will be stored in the current modifier's | |
1619 | * resolved_ids and resolved_sizes such that it can | |
1620 | * save us a few type-following when we use it later (e.g. in | |
1621 | * pretty print). | |
1622 | */ | |
2667a262 MKL |
1623 | if (!btf_type_id_size(btf, &next_type_id, &next_type_size)) { |
1624 | if (env_type_is_resolved(env, next_type_id)) | |
1625 | next_type = btf_type_id_resolve(btf, &next_type_id); | |
1626 | ||
1627 | /* "typedef void new_void", "const void"...etc */ | |
1628 | if (!btf_type_is_void(next_type) && | |
81f5c6f5 YS |
1629 | !btf_type_is_fwd(next_type) && |
1630 | !btf_type_is_func_proto(next_type)) { | |
2667a262 MKL |
1631 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
1632 | return -EINVAL; | |
1633 | } | |
eb3f595d MKL |
1634 | } |
1635 | ||
eb3f595d MKL |
1636 | env_stack_pop_resolved(env, next_type_id, next_type_size); |
1637 | ||
1638 | return 0; | |
1639 | } | |
1640 | ||
1dc92851 DB |
1641 | static int btf_var_resolve(struct btf_verifier_env *env, |
1642 | const struct resolve_vertex *v) | |
1643 | { | |
1644 | const struct btf_type *next_type; | |
1645 | const struct btf_type *t = v->t; | |
1646 | u32 next_type_id = t->type; | |
1647 | struct btf *btf = env->btf; | |
1648 | u32 next_type_size; | |
1649 | ||
1650 | next_type = btf_type_by_id(btf, next_type_id); | |
1651 | if (!next_type || btf_type_is_resolve_source_only(next_type)) { | |
1652 | btf_verifier_log_type(env, v->t, "Invalid type_id"); | |
1653 | return -EINVAL; | |
1654 | } | |
1655 | ||
1656 | if (!env_type_is_resolve_sink(env, next_type) && | |
1657 | !env_type_is_resolved(env, next_type_id)) | |
1658 | return env_stack_push(env, next_type, next_type_id); | |
1659 | ||
1660 | if (btf_type_is_modifier(next_type)) { | |
1661 | const struct btf_type *resolved_type; | |
1662 | u32 resolved_type_id; | |
1663 | ||
1664 | resolved_type_id = next_type_id; | |
1665 | resolved_type = btf_type_id_resolve(btf, &resolved_type_id); | |
1666 | ||
1667 | if (btf_type_is_ptr(resolved_type) && | |
1668 | !env_type_is_resolve_sink(env, resolved_type) && | |
1669 | !env_type_is_resolved(env, resolved_type_id)) | |
1670 | return env_stack_push(env, resolved_type, | |
1671 | resolved_type_id); | |
1672 | } | |
1673 | ||
1674 | /* We must resolve to something concrete at this point, no | |
1675 | * forward types or similar that would resolve to size of | |
1676 | * zero is allowed. | |
1677 | */ | |
1678 | if (!btf_type_id_size(btf, &next_type_id, &next_type_size)) { | |
1679 | btf_verifier_log_type(env, v->t, "Invalid type_id"); | |
1680 | return -EINVAL; | |
1681 | } | |
1682 | ||
1683 | env_stack_pop_resolved(env, next_type_id, next_type_size); | |
1684 | ||
1685 | return 0; | |
1686 | } | |
1687 | ||
eb3f595d MKL |
1688 | static int btf_ptr_resolve(struct btf_verifier_env *env, |
1689 | const struct resolve_vertex *v) | |
1690 | { | |
1691 | const struct btf_type *next_type; | |
1692 | const struct btf_type *t = v->t; | |
1693 | u32 next_type_id = t->type; | |
1694 | struct btf *btf = env->btf; | |
eb3f595d MKL |
1695 | |
1696 | next_type = btf_type_by_id(btf, next_type_id); | |
1dc92851 | 1697 | if (!next_type || btf_type_is_resolve_source_only(next_type)) { |
eb3f595d MKL |
1698 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
1699 | return -EINVAL; | |
1700 | } | |
1701 | ||
eb3f595d MKL |
1702 | if (!env_type_is_resolve_sink(env, next_type) && |
1703 | !env_type_is_resolved(env, next_type_id)) | |
1704 | return env_stack_push(env, next_type, next_type_id); | |
1705 | ||
1706 | /* If the modifier was RESOLVED during RESOLVE_STRUCT_OR_ARRAY, | |
1707 | * the modifier may have stopped resolving when it was resolved | |
1708 | * to a ptr (last-resolved-ptr). | |
1709 | * | |
1710 | * We now need to continue from the last-resolved-ptr to | |
1711 | * ensure the last-resolved-ptr will not referring back to | |
1712 | * the currenct ptr (t). | |
1713 | */ | |
1714 | if (btf_type_is_modifier(next_type)) { | |
1715 | const struct btf_type *resolved_type; | |
1716 | u32 resolved_type_id; | |
1717 | ||
1718 | resolved_type_id = next_type_id; | |
1719 | resolved_type = btf_type_id_resolve(btf, &resolved_type_id); | |
1720 | ||
1721 | if (btf_type_is_ptr(resolved_type) && | |
1722 | !env_type_is_resolve_sink(env, resolved_type) && | |
1723 | !env_type_is_resolved(env, resolved_type_id)) | |
1724 | return env_stack_push(env, resolved_type, | |
1725 | resolved_type_id); | |
1726 | } | |
1727 | ||
2667a262 MKL |
1728 | if (!btf_type_id_size(btf, &next_type_id, NULL)) { |
1729 | if (env_type_is_resolved(env, next_type_id)) | |
1730 | next_type = btf_type_id_resolve(btf, &next_type_id); | |
1731 | ||
1732 | if (!btf_type_is_void(next_type) && | |
1733 | !btf_type_is_fwd(next_type) && | |
1734 | !btf_type_is_func_proto(next_type)) { | |
1735 | btf_verifier_log_type(env, v->t, "Invalid type_id"); | |
1736 | return -EINVAL; | |
1737 | } | |
eb3f595d MKL |
1738 | } |
1739 | ||
eb3f595d MKL |
1740 | env_stack_pop_resolved(env, next_type_id, 0); |
1741 | ||
1742 | return 0; | |
1743 | } | |
1744 | ||
b00b8dae MKL |
1745 | static void btf_modifier_seq_show(const struct btf *btf, |
1746 | const struct btf_type *t, | |
1747 | u32 type_id, void *data, | |
1748 | u8 bits_offset, struct seq_file *m) | |
1749 | { | |
1750 | t = btf_type_id_resolve(btf, &type_id); | |
1751 | ||
1752 | btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m); | |
1753 | } | |
1754 | ||
1dc92851 DB |
1755 | static void btf_var_seq_show(const struct btf *btf, const struct btf_type *t, |
1756 | u32 type_id, void *data, u8 bits_offset, | |
1757 | struct seq_file *m) | |
1758 | { | |
1759 | t = btf_type_id_resolve(btf, &type_id); | |
1760 | ||
1761 | btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m); | |
1762 | } | |
1763 | ||
b00b8dae MKL |
1764 | static void btf_ptr_seq_show(const struct btf *btf, const struct btf_type *t, |
1765 | u32 type_id, void *data, u8 bits_offset, | |
1766 | struct seq_file *m) | |
1767 | { | |
1768 | /* It is a hashed value */ | |
1769 | seq_printf(m, "%p", *(void **)data); | |
1770 | } | |
1771 | ||
69b693f0 MKL |
1772 | static void btf_ref_type_log(struct btf_verifier_env *env, |
1773 | const struct btf_type *t) | |
1774 | { | |
1775 | btf_verifier_log(env, "type_id=%u", t->type); | |
1776 | } | |
1777 | ||
1778 | static struct btf_kind_operations modifier_ops = { | |
1779 | .check_meta = btf_ref_type_check_meta, | |
eb3f595d | 1780 | .resolve = btf_modifier_resolve, |
179cde8c | 1781 | .check_member = btf_modifier_check_member, |
9d5f9f70 | 1782 | .check_kflag_member = btf_modifier_check_kflag_member, |
69b693f0 | 1783 | .log_details = btf_ref_type_log, |
b00b8dae | 1784 | .seq_show = btf_modifier_seq_show, |
69b693f0 MKL |
1785 | }; |
1786 | ||
1787 | static struct btf_kind_operations ptr_ops = { | |
1788 | .check_meta = btf_ref_type_check_meta, | |
eb3f595d | 1789 | .resolve = btf_ptr_resolve, |
179cde8c | 1790 | .check_member = btf_ptr_check_member, |
9d5f9f70 | 1791 | .check_kflag_member = btf_generic_check_kflag_member, |
69b693f0 | 1792 | .log_details = btf_ref_type_log, |
b00b8dae | 1793 | .seq_show = btf_ptr_seq_show, |
69b693f0 MKL |
1794 | }; |
1795 | ||
8175383f MKL |
1796 | static s32 btf_fwd_check_meta(struct btf_verifier_env *env, |
1797 | const struct btf_type *t, | |
1798 | u32 meta_left) | |
1799 | { | |
1800 | if (btf_type_vlen(t)) { | |
1801 | btf_verifier_log_type(env, t, "vlen != 0"); | |
1802 | return -EINVAL; | |
1803 | } | |
1804 | ||
1805 | if (t->type) { | |
1806 | btf_verifier_log_type(env, t, "type != 0"); | |
1807 | return -EINVAL; | |
1808 | } | |
1809 | ||
eb04bbb6 YS |
1810 | /* fwd type must have a valid name */ |
1811 | if (!t->name_off || | |
1812 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
1813 | btf_verifier_log_type(env, t, "Invalid name"); | |
1814 | return -EINVAL; | |
1815 | } | |
1816 | ||
8175383f MKL |
1817 | btf_verifier_log_type(env, t, NULL); |
1818 | ||
1819 | return 0; | |
1820 | } | |
1821 | ||
76c43ae8 YS |
1822 | static void btf_fwd_type_log(struct btf_verifier_env *env, |
1823 | const struct btf_type *t) | |
1824 | { | |
1825 | btf_verifier_log(env, "%s", btf_type_kflag(t) ? "union" : "struct"); | |
1826 | } | |
1827 | ||
69b693f0 | 1828 | static struct btf_kind_operations fwd_ops = { |
8175383f | 1829 | .check_meta = btf_fwd_check_meta, |
eb3f595d | 1830 | .resolve = btf_df_resolve, |
179cde8c | 1831 | .check_member = btf_df_check_member, |
9d5f9f70 | 1832 | .check_kflag_member = btf_df_check_kflag_member, |
76c43ae8 | 1833 | .log_details = btf_fwd_type_log, |
b00b8dae | 1834 | .seq_show = btf_df_seq_show, |
69b693f0 MKL |
1835 | }; |
1836 | ||
179cde8c MKL |
1837 | static int btf_array_check_member(struct btf_verifier_env *env, |
1838 | const struct btf_type *struct_type, | |
1839 | const struct btf_member *member, | |
1840 | const struct btf_type *member_type) | |
1841 | { | |
1842 | u32 struct_bits_off = member->offset; | |
1843 | u32 struct_size, bytes_offset; | |
1844 | u32 array_type_id, array_size; | |
1845 | struct btf *btf = env->btf; | |
1846 | ||
1847 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
1848 | btf_verifier_log_member(env, struct_type, member, | |
1849 | "Member is not byte aligned"); | |
1850 | return -EINVAL; | |
1851 | } | |
1852 | ||
1853 | array_type_id = member->type; | |
1854 | btf_type_id_size(btf, &array_type_id, &array_size); | |
1855 | struct_size = struct_type->size; | |
1856 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
1857 | if (struct_size - bytes_offset < array_size) { | |
1858 | btf_verifier_log_member(env, struct_type, member, | |
1859 | "Member exceeds struct_size"); | |
1860 | return -EINVAL; | |
1861 | } | |
1862 | ||
1863 | return 0; | |
1864 | } | |
1865 | ||
69b693f0 MKL |
1866 | static s32 btf_array_check_meta(struct btf_verifier_env *env, |
1867 | const struct btf_type *t, | |
1868 | u32 meta_left) | |
1869 | { | |
1870 | const struct btf_array *array = btf_type_array(t); | |
1871 | u32 meta_needed = sizeof(*array); | |
1872 | ||
1873 | if (meta_left < meta_needed) { | |
1874 | btf_verifier_log_basic(env, t, | |
1875 | "meta_left:%u meta_needed:%u", | |
1876 | meta_left, meta_needed); | |
1877 | return -EINVAL; | |
1878 | } | |
1879 | ||
eb04bbb6 YS |
1880 | /* array type should not have a name */ |
1881 | if (t->name_off) { | |
1882 | btf_verifier_log_type(env, t, "Invalid name"); | |
1883 | return -EINVAL; | |
1884 | } | |
1885 | ||
69b693f0 MKL |
1886 | if (btf_type_vlen(t)) { |
1887 | btf_verifier_log_type(env, t, "vlen != 0"); | |
1888 | return -EINVAL; | |
1889 | } | |
1890 | ||
9d5f9f70 YS |
1891 | if (btf_type_kflag(t)) { |
1892 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
1893 | return -EINVAL; | |
1894 | } | |
1895 | ||
b9308ae6 MKL |
1896 | if (t->size) { |
1897 | btf_verifier_log_type(env, t, "size != 0"); | |
1898 | return -EINVAL; | |
1899 | } | |
1900 | ||
4ef5f574 MKL |
1901 | /* Array elem type and index type cannot be in type void, |
1902 | * so !array->type and !array->index_type are not allowed. | |
69b693f0 | 1903 | */ |
aea2f7b8 | 1904 | if (!array->type || !BTF_TYPE_ID_VALID(array->type)) { |
4ef5f574 MKL |
1905 | btf_verifier_log_type(env, t, "Invalid elem"); |
1906 | return -EINVAL; | |
1907 | } | |
1908 | ||
aea2f7b8 | 1909 | if (!array->index_type || !BTF_TYPE_ID_VALID(array->index_type)) { |
4ef5f574 | 1910 | btf_verifier_log_type(env, t, "Invalid index"); |
69b693f0 MKL |
1911 | return -EINVAL; |
1912 | } | |
1913 | ||
1914 | btf_verifier_log_type(env, t, NULL); | |
1915 | ||
1916 | return meta_needed; | |
1917 | } | |
1918 | ||
eb3f595d MKL |
1919 | static int btf_array_resolve(struct btf_verifier_env *env, |
1920 | const struct resolve_vertex *v) | |
1921 | { | |
1922 | const struct btf_array *array = btf_type_array(v->t); | |
4ef5f574 MKL |
1923 | const struct btf_type *elem_type, *index_type; |
1924 | u32 elem_type_id, index_type_id; | |
eb3f595d MKL |
1925 | struct btf *btf = env->btf; |
1926 | u32 elem_size; | |
1927 | ||
4ef5f574 MKL |
1928 | /* Check array->index_type */ |
1929 | index_type_id = array->index_type; | |
1930 | index_type = btf_type_by_id(btf, index_type_id); | |
1dc92851 DB |
1931 | if (btf_type_is_resolve_source_only(index_type) || |
1932 | btf_type_nosize_or_null(index_type)) { | |
4ef5f574 MKL |
1933 | btf_verifier_log_type(env, v->t, "Invalid index"); |
1934 | return -EINVAL; | |
1935 | } | |
1936 | ||
1937 | if (!env_type_is_resolve_sink(env, index_type) && | |
1938 | !env_type_is_resolved(env, index_type_id)) | |
1939 | return env_stack_push(env, index_type, index_type_id); | |
1940 | ||
1941 | index_type = btf_type_id_size(btf, &index_type_id, NULL); | |
1942 | if (!index_type || !btf_type_is_int(index_type) || | |
1943 | !btf_type_int_is_regular(index_type)) { | |
1944 | btf_verifier_log_type(env, v->t, "Invalid index"); | |
1945 | return -EINVAL; | |
1946 | } | |
1947 | ||
1948 | /* Check array->type */ | |
1949 | elem_type_id = array->type; | |
eb3f595d | 1950 | elem_type = btf_type_by_id(btf, elem_type_id); |
1dc92851 DB |
1951 | if (btf_type_is_resolve_source_only(elem_type) || |
1952 | btf_type_nosize_or_null(elem_type)) { | |
eb3f595d MKL |
1953 | btf_verifier_log_type(env, v->t, |
1954 | "Invalid elem"); | |
1955 | return -EINVAL; | |
1956 | } | |
1957 | ||
1958 | if (!env_type_is_resolve_sink(env, elem_type) && | |
1959 | !env_type_is_resolved(env, elem_type_id)) | |
1960 | return env_stack_push(env, elem_type, elem_type_id); | |
1961 | ||
1962 | elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size); | |
1963 | if (!elem_type) { | |
1964 | btf_verifier_log_type(env, v->t, "Invalid elem"); | |
1965 | return -EINVAL; | |
1966 | } | |
1967 | ||
4ef5f574 MKL |
1968 | if (btf_type_is_int(elem_type) && !btf_type_int_is_regular(elem_type)) { |
1969 | btf_verifier_log_type(env, v->t, "Invalid array of int"); | |
1970 | return -EINVAL; | |
eb3f595d MKL |
1971 | } |
1972 | ||
1973 | if (array->nelems && elem_size > U32_MAX / array->nelems) { | |
1974 | btf_verifier_log_type(env, v->t, | |
1975 | "Array size overflows U32_MAX"); | |
1976 | return -EINVAL; | |
1977 | } | |
1978 | ||
1979 | env_stack_pop_resolved(env, elem_type_id, elem_size * array->nelems); | |
1980 | ||
1981 | return 0; | |
1982 | } | |
1983 | ||
69b693f0 MKL |
1984 | static void btf_array_log(struct btf_verifier_env *env, |
1985 | const struct btf_type *t) | |
1986 | { | |
1987 | const struct btf_array *array = btf_type_array(t); | |
1988 | ||
1989 | btf_verifier_log(env, "type_id=%u index_type_id=%u nr_elems=%u", | |
1990 | array->type, array->index_type, array->nelems); | |
1991 | } | |
1992 | ||
b00b8dae MKL |
1993 | static void btf_array_seq_show(const struct btf *btf, const struct btf_type *t, |
1994 | u32 type_id, void *data, u8 bits_offset, | |
1995 | struct seq_file *m) | |
1996 | { | |
1997 | const struct btf_array *array = btf_type_array(t); | |
1998 | const struct btf_kind_operations *elem_ops; | |
1999 | const struct btf_type *elem_type; | |
2000 | u32 i, elem_size, elem_type_id; | |
2001 | ||
2002 | elem_type_id = array->type; | |
2003 | elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size); | |
2004 | elem_ops = btf_type_ops(elem_type); | |
2005 | seq_puts(m, "["); | |
2006 | for (i = 0; i < array->nelems; i++) { | |
2007 | if (i) | |
2008 | seq_puts(m, ","); | |
2009 | ||
2010 | elem_ops->seq_show(btf, elem_type, elem_type_id, data, | |
2011 | bits_offset, m); | |
2012 | data += elem_size; | |
2013 | } | |
2014 | seq_puts(m, "]"); | |
2015 | } | |
2016 | ||
69b693f0 MKL |
2017 | static struct btf_kind_operations array_ops = { |
2018 | .check_meta = btf_array_check_meta, | |
eb3f595d | 2019 | .resolve = btf_array_resolve, |
179cde8c | 2020 | .check_member = btf_array_check_member, |
9d5f9f70 | 2021 | .check_kflag_member = btf_generic_check_kflag_member, |
69b693f0 | 2022 | .log_details = btf_array_log, |
b00b8dae | 2023 | .seq_show = btf_array_seq_show, |
69b693f0 MKL |
2024 | }; |
2025 | ||
179cde8c MKL |
2026 | static int btf_struct_check_member(struct btf_verifier_env *env, |
2027 | const struct btf_type *struct_type, | |
2028 | const struct btf_member *member, | |
2029 | const struct btf_type *member_type) | |
2030 | { | |
2031 | u32 struct_bits_off = member->offset; | |
2032 | u32 struct_size, bytes_offset; | |
2033 | ||
2034 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
2035 | btf_verifier_log_member(env, struct_type, member, | |
2036 | "Member is not byte aligned"); | |
2037 | return -EINVAL; | |
2038 | } | |
2039 | ||
2040 | struct_size = struct_type->size; | |
2041 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
2042 | if (struct_size - bytes_offset < member_type->size) { | |
2043 | btf_verifier_log_member(env, struct_type, member, | |
2044 | "Member exceeds struct_size"); | |
2045 | return -EINVAL; | |
2046 | } | |
2047 | ||
2048 | return 0; | |
2049 | } | |
2050 | ||
69b693f0 MKL |
2051 | static s32 btf_struct_check_meta(struct btf_verifier_env *env, |
2052 | const struct btf_type *t, | |
2053 | u32 meta_left) | |
2054 | { | |
2055 | bool is_union = BTF_INFO_KIND(t->info) == BTF_KIND_UNION; | |
2056 | const struct btf_member *member; | |
6283fa38 | 2057 | u32 meta_needed, last_offset; |
69b693f0 MKL |
2058 | struct btf *btf = env->btf; |
2059 | u32 struct_size = t->size; | |
9d5f9f70 | 2060 | u32 offset; |
69b693f0 MKL |
2061 | u16 i; |
2062 | ||
2063 | meta_needed = btf_type_vlen(t) * sizeof(*member); | |
2064 | if (meta_left < meta_needed) { | |
2065 | btf_verifier_log_basic(env, t, | |
2066 | "meta_left:%u meta_needed:%u", | |
2067 | meta_left, meta_needed); | |
2068 | return -EINVAL; | |
2069 | } | |
2070 | ||
eb04bbb6 YS |
2071 | /* struct type either no name or a valid one */ |
2072 | if (t->name_off && | |
2073 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
2074 | btf_verifier_log_type(env, t, "Invalid name"); | |
2075 | return -EINVAL; | |
2076 | } | |
2077 | ||
69b693f0 MKL |
2078 | btf_verifier_log_type(env, t, NULL); |
2079 | ||
6283fa38 | 2080 | last_offset = 0; |
69b693f0 | 2081 | for_each_member(i, t, member) { |
fbcf93eb | 2082 | if (!btf_name_offset_valid(btf, member->name_off)) { |
69b693f0 MKL |
2083 | btf_verifier_log_member(env, t, member, |
2084 | "Invalid member name_offset:%u", | |
fbcf93eb | 2085 | member->name_off); |
69b693f0 MKL |
2086 | return -EINVAL; |
2087 | } | |
2088 | ||
eb04bbb6 YS |
2089 | /* struct member either no name or a valid one */ |
2090 | if (member->name_off && | |
2091 | !btf_name_valid_identifier(btf, member->name_off)) { | |
2092 | btf_verifier_log_member(env, t, member, "Invalid name"); | |
2093 | return -EINVAL; | |
2094 | } | |
69b693f0 | 2095 | /* A member cannot be in type void */ |
aea2f7b8 | 2096 | if (!member->type || !BTF_TYPE_ID_VALID(member->type)) { |
69b693f0 MKL |
2097 | btf_verifier_log_member(env, t, member, |
2098 | "Invalid type_id"); | |
2099 | return -EINVAL; | |
2100 | } | |
2101 | ||
9d5f9f70 YS |
2102 | offset = btf_member_bit_offset(t, member); |
2103 | if (is_union && offset) { | |
69b693f0 MKL |
2104 | btf_verifier_log_member(env, t, member, |
2105 | "Invalid member bits_offset"); | |
2106 | return -EINVAL; | |
2107 | } | |
2108 | ||
6283fa38 MKL |
2109 | /* |
2110 | * ">" instead of ">=" because the last member could be | |
2111 | * "char a[0];" | |
2112 | */ | |
9d5f9f70 | 2113 | if (last_offset > offset) { |
6283fa38 MKL |
2114 | btf_verifier_log_member(env, t, member, |
2115 | "Invalid member bits_offset"); | |
2116 | return -EINVAL; | |
2117 | } | |
2118 | ||
9d5f9f70 | 2119 | if (BITS_ROUNDUP_BYTES(offset) > struct_size) { |
69b693f0 | 2120 | btf_verifier_log_member(env, t, member, |
311fe1a8 | 2121 | "Member bits_offset exceeds its struct size"); |
69b693f0 MKL |
2122 | return -EINVAL; |
2123 | } | |
2124 | ||
2125 | btf_verifier_log_member(env, t, member, NULL); | |
9d5f9f70 | 2126 | last_offset = offset; |
69b693f0 MKL |
2127 | } |
2128 | ||
2129 | return meta_needed; | |
2130 | } | |
2131 | ||
eb3f595d MKL |
2132 | static int btf_struct_resolve(struct btf_verifier_env *env, |
2133 | const struct resolve_vertex *v) | |
2134 | { | |
2135 | const struct btf_member *member; | |
179cde8c | 2136 | int err; |
eb3f595d MKL |
2137 | u16 i; |
2138 | ||
2139 | /* Before continue resolving the next_member, | |
2140 | * ensure the last member is indeed resolved to a | |
2141 | * type with size info. | |
2142 | */ | |
2143 | if (v->next_member) { | |
179cde8c | 2144 | const struct btf_type *last_member_type; |
eb3f595d MKL |
2145 | const struct btf_member *last_member; |
2146 | u16 last_member_type_id; | |
2147 | ||
2148 | last_member = btf_type_member(v->t) + v->next_member - 1; | |
2149 | last_member_type_id = last_member->type; | |
2150 | if (WARN_ON_ONCE(!env_type_is_resolved(env, | |
2151 | last_member_type_id))) | |
2152 | return -EINVAL; | |
179cde8c MKL |
2153 | |
2154 | last_member_type = btf_type_by_id(env->btf, | |
2155 | last_member_type_id); | |
9d5f9f70 YS |
2156 | if (btf_type_kflag(v->t)) |
2157 | err = btf_type_ops(last_member_type)->check_kflag_member(env, v->t, | |
2158 | last_member, | |
2159 | last_member_type); | |
2160 | else | |
2161 | err = btf_type_ops(last_member_type)->check_member(env, v->t, | |
2162 | last_member, | |
2163 | last_member_type); | |
179cde8c MKL |
2164 | if (err) |
2165 | return err; | |
eb3f595d MKL |
2166 | } |
2167 | ||
2168 | for_each_member_from(i, v->next_member, v->t, member) { | |
2169 | u32 member_type_id = member->type; | |
2170 | const struct btf_type *member_type = btf_type_by_id(env->btf, | |
2171 | member_type_id); | |
2172 | ||
1dc92851 DB |
2173 | if (btf_type_is_resolve_source_only(member_type) || |
2174 | btf_type_nosize_or_null(member_type)) { | |
eb3f595d MKL |
2175 | btf_verifier_log_member(env, v->t, member, |
2176 | "Invalid member"); | |
2177 | return -EINVAL; | |
2178 | } | |
2179 | ||
2180 | if (!env_type_is_resolve_sink(env, member_type) && | |
2181 | !env_type_is_resolved(env, member_type_id)) { | |
2182 | env_stack_set_next_member(env, i + 1); | |
2183 | return env_stack_push(env, member_type, member_type_id); | |
2184 | } | |
179cde8c | 2185 | |
9d5f9f70 YS |
2186 | if (btf_type_kflag(v->t)) |
2187 | err = btf_type_ops(member_type)->check_kflag_member(env, v->t, | |
2188 | member, | |
2189 | member_type); | |
2190 | else | |
2191 | err = btf_type_ops(member_type)->check_member(env, v->t, | |
2192 | member, | |
2193 | member_type); | |
179cde8c MKL |
2194 | if (err) |
2195 | return err; | |
eb3f595d MKL |
2196 | } |
2197 | ||
2198 | env_stack_pop_resolved(env, 0, 0); | |
2199 | ||
2200 | return 0; | |
2201 | } | |
2202 | ||
69b693f0 MKL |
2203 | static void btf_struct_log(struct btf_verifier_env *env, |
2204 | const struct btf_type *t) | |
2205 | { | |
2206 | btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); | |
2207 | } | |
2208 | ||
d83525ca AS |
2209 | /* find 'struct bpf_spin_lock' in map value. |
2210 | * return >= 0 offset if found | |
2211 | * and < 0 in case of error | |
2212 | */ | |
2213 | int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t) | |
2214 | { | |
2215 | const struct btf_member *member; | |
2216 | u32 i, off = -ENOENT; | |
2217 | ||
2218 | if (!__btf_type_is_struct(t)) | |
2219 | return -EINVAL; | |
2220 | ||
2221 | for_each_member(i, t, member) { | |
2222 | const struct btf_type *member_type = btf_type_by_id(btf, | |
2223 | member->type); | |
2224 | if (!__btf_type_is_struct(member_type)) | |
2225 | continue; | |
2226 | if (member_type->size != sizeof(struct bpf_spin_lock)) | |
2227 | continue; | |
2228 | if (strcmp(__btf_name_by_offset(btf, member_type->name_off), | |
2229 | "bpf_spin_lock")) | |
2230 | continue; | |
2231 | if (off != -ENOENT) | |
2232 | /* only one 'struct bpf_spin_lock' is allowed */ | |
2233 | return -E2BIG; | |
2234 | off = btf_member_bit_offset(t, member); | |
2235 | if (off % 8) | |
2236 | /* valid C code cannot generate such BTF */ | |
2237 | return -EINVAL; | |
2238 | off /= 8; | |
2239 | if (off % __alignof__(struct bpf_spin_lock)) | |
2240 | /* valid struct bpf_spin_lock will be 4 byte aligned */ | |
2241 | return -EINVAL; | |
2242 | } | |
2243 | return off; | |
2244 | } | |
2245 | ||
b00b8dae MKL |
2246 | static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t, |
2247 | u32 type_id, void *data, u8 bits_offset, | |
2248 | struct seq_file *m) | |
2249 | { | |
2250 | const char *seq = BTF_INFO_KIND(t->info) == BTF_KIND_UNION ? "|" : ","; | |
2251 | const struct btf_member *member; | |
2252 | u32 i; | |
2253 | ||
2254 | seq_puts(m, "{"); | |
2255 | for_each_member(i, t, member) { | |
2256 | const struct btf_type *member_type = btf_type_by_id(btf, | |
2257 | member->type); | |
b00b8dae | 2258 | const struct btf_kind_operations *ops; |
9d5f9f70 YS |
2259 | u32 member_offset, bitfield_size; |
2260 | u32 bytes_offset; | |
2261 | u8 bits8_offset; | |
b00b8dae MKL |
2262 | |
2263 | if (i) | |
2264 | seq_puts(m, seq); | |
2265 | ||
9d5f9f70 YS |
2266 | member_offset = btf_member_bit_offset(t, member); |
2267 | bitfield_size = btf_member_bitfield_size(t, member); | |
17e3ac81 YS |
2268 | bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); |
2269 | bits8_offset = BITS_PER_BYTE_MASKED(member_offset); | |
9d5f9f70 | 2270 | if (bitfield_size) { |
17e3ac81 | 2271 | btf_bitfield_seq_show(data + bytes_offset, bits8_offset, |
9d5f9f70 YS |
2272 | bitfield_size, m); |
2273 | } else { | |
9d5f9f70 YS |
2274 | ops = btf_type_ops(member_type); |
2275 | ops->seq_show(btf, member_type, member->type, | |
2276 | data + bytes_offset, bits8_offset, m); | |
2277 | } | |
b00b8dae MKL |
2278 | } |
2279 | seq_puts(m, "}"); | |
2280 | } | |
2281 | ||
69b693f0 MKL |
2282 | static struct btf_kind_operations struct_ops = { |
2283 | .check_meta = btf_struct_check_meta, | |
eb3f595d | 2284 | .resolve = btf_struct_resolve, |
179cde8c | 2285 | .check_member = btf_struct_check_member, |
9d5f9f70 | 2286 | .check_kflag_member = btf_generic_check_kflag_member, |
69b693f0 | 2287 | .log_details = btf_struct_log, |
b00b8dae | 2288 | .seq_show = btf_struct_seq_show, |
69b693f0 MKL |
2289 | }; |
2290 | ||
179cde8c MKL |
2291 | static int btf_enum_check_member(struct btf_verifier_env *env, |
2292 | const struct btf_type *struct_type, | |
2293 | const struct btf_member *member, | |
2294 | const struct btf_type *member_type) | |
2295 | { | |
2296 | u32 struct_bits_off = member->offset; | |
2297 | u32 struct_size, bytes_offset; | |
2298 | ||
2299 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
2300 | btf_verifier_log_member(env, struct_type, member, | |
2301 | "Member is not byte aligned"); | |
2302 | return -EINVAL; | |
2303 | } | |
2304 | ||
2305 | struct_size = struct_type->size; | |
2306 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
2307 | if (struct_size - bytes_offset < sizeof(int)) { | |
2308 | btf_verifier_log_member(env, struct_type, member, | |
2309 | "Member exceeds struct_size"); | |
2310 | return -EINVAL; | |
2311 | } | |
2312 | ||
2313 | return 0; | |
2314 | } | |
2315 | ||
9d5f9f70 YS |
2316 | static int btf_enum_check_kflag_member(struct btf_verifier_env *env, |
2317 | const struct btf_type *struct_type, | |
2318 | const struct btf_member *member, | |
2319 | const struct btf_type *member_type) | |
2320 | { | |
2321 | u32 struct_bits_off, nr_bits, bytes_end, struct_size; | |
2322 | u32 int_bitsize = sizeof(int) * BITS_PER_BYTE; | |
2323 | ||
2324 | struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset); | |
2325 | nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset); | |
2326 | if (!nr_bits) { | |
2327 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
2328 | btf_verifier_log_member(env, struct_type, member, | |
2329 | "Member is not byte aligned"); | |
2330 | return -EINVAL; | |
2331 | } | |
2332 | ||
2333 | nr_bits = int_bitsize; | |
2334 | } else if (nr_bits > int_bitsize) { | |
2335 | btf_verifier_log_member(env, struct_type, member, | |
2336 | "Invalid member bitfield_size"); | |
2337 | return -EINVAL; | |
2338 | } | |
2339 | ||
2340 | struct_size = struct_type->size; | |
2341 | bytes_end = BITS_ROUNDUP_BYTES(struct_bits_off + nr_bits); | |
2342 | if (struct_size < bytes_end) { | |
2343 | btf_verifier_log_member(env, struct_type, member, | |
2344 | "Member exceeds struct_size"); | |
2345 | return -EINVAL; | |
2346 | } | |
2347 | ||
2348 | return 0; | |
2349 | } | |
2350 | ||
69b693f0 MKL |
2351 | static s32 btf_enum_check_meta(struct btf_verifier_env *env, |
2352 | const struct btf_type *t, | |
2353 | u32 meta_left) | |
2354 | { | |
2355 | const struct btf_enum *enums = btf_type_enum(t); | |
2356 | struct btf *btf = env->btf; | |
2357 | u16 i, nr_enums; | |
2358 | u32 meta_needed; | |
2359 | ||
2360 | nr_enums = btf_type_vlen(t); | |
2361 | meta_needed = nr_enums * sizeof(*enums); | |
2362 | ||
2363 | if (meta_left < meta_needed) { | |
2364 | btf_verifier_log_basic(env, t, | |
2365 | "meta_left:%u meta_needed:%u", | |
2366 | meta_left, meta_needed); | |
2367 | return -EINVAL; | |
2368 | } | |
2369 | ||
9d5f9f70 YS |
2370 | if (btf_type_kflag(t)) { |
2371 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2372 | return -EINVAL; | |
2373 | } | |
2374 | ||
69b693f0 MKL |
2375 | if (t->size != sizeof(int)) { |
2376 | btf_verifier_log_type(env, t, "Expected size:%zu", | |
2377 | sizeof(int)); | |
2378 | return -EINVAL; | |
2379 | } | |
2380 | ||
eb04bbb6 YS |
2381 | /* enum type either no name or a valid one */ |
2382 | if (t->name_off && | |
2383 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
2384 | btf_verifier_log_type(env, t, "Invalid name"); | |
2385 | return -EINVAL; | |
2386 | } | |
2387 | ||
69b693f0 MKL |
2388 | btf_verifier_log_type(env, t, NULL); |
2389 | ||
2390 | for (i = 0; i < nr_enums; i++) { | |
fbcf93eb | 2391 | if (!btf_name_offset_valid(btf, enums[i].name_off)) { |
69b693f0 | 2392 | btf_verifier_log(env, "\tInvalid name_offset:%u", |
fbcf93eb | 2393 | enums[i].name_off); |
69b693f0 MKL |
2394 | return -EINVAL; |
2395 | } | |
2396 | ||
eb04bbb6 YS |
2397 | /* enum member must have a valid name */ |
2398 | if (!enums[i].name_off || | |
2399 | !btf_name_valid_identifier(btf, enums[i].name_off)) { | |
2400 | btf_verifier_log_type(env, t, "Invalid name"); | |
2401 | return -EINVAL; | |
2402 | } | |
2403 | ||
2404 | ||
69b693f0 | 2405 | btf_verifier_log(env, "\t%s val=%d\n", |
23127b33 | 2406 | __btf_name_by_offset(btf, enums[i].name_off), |
69b693f0 MKL |
2407 | enums[i].val); |
2408 | } | |
2409 | ||
2410 | return meta_needed; | |
2411 | } | |
2412 | ||
2413 | static void btf_enum_log(struct btf_verifier_env *env, | |
2414 | const struct btf_type *t) | |
2415 | { | |
2416 | btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); | |
2417 | } | |
2418 | ||
b00b8dae MKL |
2419 | static void btf_enum_seq_show(const struct btf *btf, const struct btf_type *t, |
2420 | u32 type_id, void *data, u8 bits_offset, | |
2421 | struct seq_file *m) | |
2422 | { | |
2423 | const struct btf_enum *enums = btf_type_enum(t); | |
2424 | u32 i, nr_enums = btf_type_vlen(t); | |
2425 | int v = *(int *)data; | |
2426 | ||
2427 | for (i = 0; i < nr_enums; i++) { | |
2428 | if (v == enums[i].val) { | |
2429 | seq_printf(m, "%s", | |
23127b33 MKL |
2430 | __btf_name_by_offset(btf, |
2431 | enums[i].name_off)); | |
b00b8dae MKL |
2432 | return; |
2433 | } | |
2434 | } | |
2435 | ||
2436 | seq_printf(m, "%d", v); | |
2437 | } | |
2438 | ||
69b693f0 MKL |
2439 | static struct btf_kind_operations enum_ops = { |
2440 | .check_meta = btf_enum_check_meta, | |
eb3f595d | 2441 | .resolve = btf_df_resolve, |
179cde8c | 2442 | .check_member = btf_enum_check_member, |
9d5f9f70 | 2443 | .check_kflag_member = btf_enum_check_kflag_member, |
69b693f0 | 2444 | .log_details = btf_enum_log, |
b00b8dae | 2445 | .seq_show = btf_enum_seq_show, |
69b693f0 MKL |
2446 | }; |
2447 | ||
2667a262 MKL |
2448 | static s32 btf_func_proto_check_meta(struct btf_verifier_env *env, |
2449 | const struct btf_type *t, | |
2450 | u32 meta_left) | |
2451 | { | |
2452 | u32 meta_needed = btf_type_vlen(t) * sizeof(struct btf_param); | |
2453 | ||
2454 | if (meta_left < meta_needed) { | |
2455 | btf_verifier_log_basic(env, t, | |
2456 | "meta_left:%u meta_needed:%u", | |
2457 | meta_left, meta_needed); | |
2458 | return -EINVAL; | |
2459 | } | |
2460 | ||
2461 | if (t->name_off) { | |
2462 | btf_verifier_log_type(env, t, "Invalid name"); | |
2463 | return -EINVAL; | |
2464 | } | |
2465 | ||
9d5f9f70 YS |
2466 | if (btf_type_kflag(t)) { |
2467 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2468 | return -EINVAL; | |
2469 | } | |
2470 | ||
2667a262 MKL |
2471 | btf_verifier_log_type(env, t, NULL); |
2472 | ||
2473 | return meta_needed; | |
2474 | } | |
2475 | ||
2476 | static void btf_func_proto_log(struct btf_verifier_env *env, | |
2477 | const struct btf_type *t) | |
2478 | { | |
2479 | const struct btf_param *args = (const struct btf_param *)(t + 1); | |
2480 | u16 nr_args = btf_type_vlen(t), i; | |
2481 | ||
2482 | btf_verifier_log(env, "return=%u args=(", t->type); | |
2483 | if (!nr_args) { | |
2484 | btf_verifier_log(env, "void"); | |
2485 | goto done; | |
2486 | } | |
2487 | ||
2488 | if (nr_args == 1 && !args[0].type) { | |
2489 | /* Only one vararg */ | |
2490 | btf_verifier_log(env, "vararg"); | |
2491 | goto done; | |
2492 | } | |
2493 | ||
2494 | btf_verifier_log(env, "%u %s", args[0].type, | |
23127b33 MKL |
2495 | __btf_name_by_offset(env->btf, |
2496 | args[0].name_off)); | |
2667a262 MKL |
2497 | for (i = 1; i < nr_args - 1; i++) |
2498 | btf_verifier_log(env, ", %u %s", args[i].type, | |
23127b33 MKL |
2499 | __btf_name_by_offset(env->btf, |
2500 | args[i].name_off)); | |
2667a262 MKL |
2501 | |
2502 | if (nr_args > 1) { | |
2503 | const struct btf_param *last_arg = &args[nr_args - 1]; | |
2504 | ||
2505 | if (last_arg->type) | |
2506 | btf_verifier_log(env, ", %u %s", last_arg->type, | |
23127b33 MKL |
2507 | __btf_name_by_offset(env->btf, |
2508 | last_arg->name_off)); | |
2667a262 MKL |
2509 | else |
2510 | btf_verifier_log(env, ", vararg"); | |
2511 | } | |
2512 | ||
2513 | done: | |
2514 | btf_verifier_log(env, ")"); | |
2515 | } | |
2516 | ||
2517 | static struct btf_kind_operations func_proto_ops = { | |
2518 | .check_meta = btf_func_proto_check_meta, | |
2519 | .resolve = btf_df_resolve, | |
2520 | /* | |
2521 | * BTF_KIND_FUNC_PROTO cannot be directly referred by | |
2522 | * a struct's member. | |
2523 | * | |
2524 | * It should be a funciton pointer instead. | |
2525 | * (i.e. struct's member -> BTF_KIND_PTR -> BTF_KIND_FUNC_PROTO) | |
2526 | * | |
2527 | * Hence, there is no btf_func_check_member(). | |
2528 | */ | |
2529 | .check_member = btf_df_check_member, | |
9d5f9f70 | 2530 | .check_kflag_member = btf_df_check_kflag_member, |
2667a262 MKL |
2531 | .log_details = btf_func_proto_log, |
2532 | .seq_show = btf_df_seq_show, | |
2533 | }; | |
2534 | ||
2535 | static s32 btf_func_check_meta(struct btf_verifier_env *env, | |
2536 | const struct btf_type *t, | |
2537 | u32 meta_left) | |
2538 | { | |
2539 | if (!t->name_off || | |
2540 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
2541 | btf_verifier_log_type(env, t, "Invalid name"); | |
2542 | return -EINVAL; | |
2543 | } | |
2544 | ||
2545 | if (btf_type_vlen(t)) { | |
2546 | btf_verifier_log_type(env, t, "vlen != 0"); | |
2547 | return -EINVAL; | |
2548 | } | |
2549 | ||
9d5f9f70 YS |
2550 | if (btf_type_kflag(t)) { |
2551 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2552 | return -EINVAL; | |
2553 | } | |
2554 | ||
2667a262 MKL |
2555 | btf_verifier_log_type(env, t, NULL); |
2556 | ||
2557 | return 0; | |
2558 | } | |
2559 | ||
2560 | static struct btf_kind_operations func_ops = { | |
2561 | .check_meta = btf_func_check_meta, | |
2562 | .resolve = btf_df_resolve, | |
2563 | .check_member = btf_df_check_member, | |
9d5f9f70 | 2564 | .check_kflag_member = btf_df_check_kflag_member, |
2667a262 MKL |
2565 | .log_details = btf_ref_type_log, |
2566 | .seq_show = btf_df_seq_show, | |
2567 | }; | |
2568 | ||
1dc92851 DB |
2569 | static s32 btf_var_check_meta(struct btf_verifier_env *env, |
2570 | const struct btf_type *t, | |
2571 | u32 meta_left) | |
2572 | { | |
2573 | const struct btf_var *var; | |
2574 | u32 meta_needed = sizeof(*var); | |
2575 | ||
2576 | if (meta_left < meta_needed) { | |
2577 | btf_verifier_log_basic(env, t, | |
2578 | "meta_left:%u meta_needed:%u", | |
2579 | meta_left, meta_needed); | |
2580 | return -EINVAL; | |
2581 | } | |
2582 | ||
2583 | if (btf_type_vlen(t)) { | |
2584 | btf_verifier_log_type(env, t, "vlen != 0"); | |
2585 | return -EINVAL; | |
2586 | } | |
2587 | ||
2588 | if (btf_type_kflag(t)) { | |
2589 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2590 | return -EINVAL; | |
2591 | } | |
2592 | ||
2593 | if (!t->name_off || | |
2594 | !__btf_name_valid(env->btf, t->name_off, true)) { | |
2595 | btf_verifier_log_type(env, t, "Invalid name"); | |
2596 | return -EINVAL; | |
2597 | } | |
2598 | ||
2599 | /* A var cannot be in type void */ | |
2600 | if (!t->type || !BTF_TYPE_ID_VALID(t->type)) { | |
2601 | btf_verifier_log_type(env, t, "Invalid type_id"); | |
2602 | return -EINVAL; | |
2603 | } | |
2604 | ||
2605 | var = btf_type_var(t); | |
2606 | if (var->linkage != BTF_VAR_STATIC && | |
2607 | var->linkage != BTF_VAR_GLOBAL_ALLOCATED) { | |
2608 | btf_verifier_log_type(env, t, "Linkage not supported"); | |
2609 | return -EINVAL; | |
2610 | } | |
2611 | ||
2612 | btf_verifier_log_type(env, t, NULL); | |
2613 | ||
2614 | return meta_needed; | |
2615 | } | |
2616 | ||
2617 | static void btf_var_log(struct btf_verifier_env *env, const struct btf_type *t) | |
2618 | { | |
2619 | const struct btf_var *var = btf_type_var(t); | |
2620 | ||
2621 | btf_verifier_log(env, "type_id=%u linkage=%u", t->type, var->linkage); | |
2622 | } | |
2623 | ||
2624 | static const struct btf_kind_operations var_ops = { | |
2625 | .check_meta = btf_var_check_meta, | |
2626 | .resolve = btf_var_resolve, | |
2627 | .check_member = btf_df_check_member, | |
2628 | .check_kflag_member = btf_df_check_kflag_member, | |
2629 | .log_details = btf_var_log, | |
2630 | .seq_show = btf_var_seq_show, | |
2631 | }; | |
2632 | ||
2633 | static s32 btf_datasec_check_meta(struct btf_verifier_env *env, | |
2634 | const struct btf_type *t, | |
2635 | u32 meta_left) | |
2636 | { | |
2637 | const struct btf_var_secinfo *vsi; | |
2638 | u64 last_vsi_end_off = 0, sum = 0; | |
2639 | u32 i, meta_needed; | |
2640 | ||
2641 | meta_needed = btf_type_vlen(t) * sizeof(*vsi); | |
2642 | if (meta_left < meta_needed) { | |
2643 | btf_verifier_log_basic(env, t, | |
2644 | "meta_left:%u meta_needed:%u", | |
2645 | meta_left, meta_needed); | |
2646 | return -EINVAL; | |
2647 | } | |
2648 | ||
2649 | if (!btf_type_vlen(t)) { | |
2650 | btf_verifier_log_type(env, t, "vlen == 0"); | |
2651 | return -EINVAL; | |
2652 | } | |
2653 | ||
2654 | if (!t->size) { | |
2655 | btf_verifier_log_type(env, t, "size == 0"); | |
2656 | return -EINVAL; | |
2657 | } | |
2658 | ||
2659 | if (btf_type_kflag(t)) { | |
2660 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2661 | return -EINVAL; | |
2662 | } | |
2663 | ||
2664 | if (!t->name_off || | |
2665 | !btf_name_valid_section(env->btf, t->name_off)) { | |
2666 | btf_verifier_log_type(env, t, "Invalid name"); | |
2667 | return -EINVAL; | |
2668 | } | |
2669 | ||
2670 | btf_verifier_log_type(env, t, NULL); | |
2671 | ||
2672 | for_each_vsi(i, t, vsi) { | |
2673 | /* A var cannot be in type void */ | |
2674 | if (!vsi->type || !BTF_TYPE_ID_VALID(vsi->type)) { | |
2675 | btf_verifier_log_vsi(env, t, vsi, | |
2676 | "Invalid type_id"); | |
2677 | return -EINVAL; | |
2678 | } | |
2679 | ||
2680 | if (vsi->offset < last_vsi_end_off || vsi->offset >= t->size) { | |
2681 | btf_verifier_log_vsi(env, t, vsi, | |
2682 | "Invalid offset"); | |
2683 | return -EINVAL; | |
2684 | } | |
2685 | ||
2686 | if (!vsi->size || vsi->size > t->size) { | |
2687 | btf_verifier_log_vsi(env, t, vsi, | |
2688 | "Invalid size"); | |
2689 | return -EINVAL; | |
2690 | } | |
2691 | ||
2692 | last_vsi_end_off = vsi->offset + vsi->size; | |
2693 | if (last_vsi_end_off > t->size) { | |
2694 | btf_verifier_log_vsi(env, t, vsi, | |
2695 | "Invalid offset+size"); | |
2696 | return -EINVAL; | |
2697 | } | |
2698 | ||
2699 | btf_verifier_log_vsi(env, t, vsi, NULL); | |
2700 | sum += vsi->size; | |
2701 | } | |
2702 | ||
2703 | if (t->size < sum) { | |
2704 | btf_verifier_log_type(env, t, "Invalid btf_info size"); | |
2705 | return -EINVAL; | |
2706 | } | |
2707 | ||
2708 | return meta_needed; | |
2709 | } | |
2710 | ||
2711 | static int btf_datasec_resolve(struct btf_verifier_env *env, | |
2712 | const struct resolve_vertex *v) | |
2713 | { | |
2714 | const struct btf_var_secinfo *vsi; | |
2715 | struct btf *btf = env->btf; | |
2716 | u16 i; | |
2717 | ||
2718 | for_each_vsi_from(i, v->next_member, v->t, vsi) { | |
2719 | u32 var_type_id = vsi->type, type_id, type_size = 0; | |
2720 | const struct btf_type *var_type = btf_type_by_id(env->btf, | |
2721 | var_type_id); | |
2722 | if (!var_type || !btf_type_is_var(var_type)) { | |
2723 | btf_verifier_log_vsi(env, v->t, vsi, | |
2724 | "Not a VAR kind member"); | |
2725 | return -EINVAL; | |
2726 | } | |
2727 | ||
2728 | if (!env_type_is_resolve_sink(env, var_type) && | |
2729 | !env_type_is_resolved(env, var_type_id)) { | |
2730 | env_stack_set_next_member(env, i + 1); | |
2731 | return env_stack_push(env, var_type, var_type_id); | |
2732 | } | |
2733 | ||
2734 | type_id = var_type->type; | |
2735 | if (!btf_type_id_size(btf, &type_id, &type_size)) { | |
2736 | btf_verifier_log_vsi(env, v->t, vsi, "Invalid type"); | |
2737 | return -EINVAL; | |
2738 | } | |
2739 | ||
2740 | if (vsi->size < type_size) { | |
2741 | btf_verifier_log_vsi(env, v->t, vsi, "Invalid size"); | |
2742 | return -EINVAL; | |
2743 | } | |
2744 | } | |
2745 | ||
2746 | env_stack_pop_resolved(env, 0, 0); | |
2747 | return 0; | |
2748 | } | |
2749 | ||
2750 | static void btf_datasec_log(struct btf_verifier_env *env, | |
2751 | const struct btf_type *t) | |
2752 | { | |
2753 | btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); | |
2754 | } | |
2755 | ||
2756 | static void btf_datasec_seq_show(const struct btf *btf, | |
2757 | const struct btf_type *t, u32 type_id, | |
2758 | void *data, u8 bits_offset, | |
2759 | struct seq_file *m) | |
2760 | { | |
2761 | const struct btf_var_secinfo *vsi; | |
2762 | const struct btf_type *var; | |
2763 | u32 i; | |
2764 | ||
2765 | seq_printf(m, "section (\"%s\") = {", __btf_name_by_offset(btf, t->name_off)); | |
2766 | for_each_vsi(i, t, vsi) { | |
2767 | var = btf_type_by_id(btf, vsi->type); | |
2768 | if (i) | |
2769 | seq_puts(m, ","); | |
2770 | btf_type_ops(var)->seq_show(btf, var, vsi->type, | |
2771 | data + vsi->offset, bits_offset, m); | |
2772 | } | |
2773 | seq_puts(m, "}"); | |
2774 | } | |
2775 | ||
2776 | static const struct btf_kind_operations datasec_ops = { | |
2777 | .check_meta = btf_datasec_check_meta, | |
2778 | .resolve = btf_datasec_resolve, | |
2779 | .check_member = btf_df_check_member, | |
2780 | .check_kflag_member = btf_df_check_kflag_member, | |
2781 | .log_details = btf_datasec_log, | |
2782 | .seq_show = btf_datasec_seq_show, | |
2783 | }; | |
2784 | ||
2667a262 MKL |
2785 | static int btf_func_proto_check(struct btf_verifier_env *env, |
2786 | const struct btf_type *t) | |
2787 | { | |
2788 | const struct btf_type *ret_type; | |
2789 | const struct btf_param *args; | |
2790 | const struct btf *btf; | |
2791 | u16 nr_args, i; | |
2792 | int err; | |
2793 | ||
2794 | btf = env->btf; | |
2795 | args = (const struct btf_param *)(t + 1); | |
2796 | nr_args = btf_type_vlen(t); | |
2797 | ||
2798 | /* Check func return type which could be "void" (t->type == 0) */ | |
2799 | if (t->type) { | |
2800 | u32 ret_type_id = t->type; | |
2801 | ||
2802 | ret_type = btf_type_by_id(btf, ret_type_id); | |
2803 | if (!ret_type) { | |
2804 | btf_verifier_log_type(env, t, "Invalid return type"); | |
2805 | return -EINVAL; | |
2806 | } | |
2807 | ||
2808 | if (btf_type_needs_resolve(ret_type) && | |
2809 | !env_type_is_resolved(env, ret_type_id)) { | |
2810 | err = btf_resolve(env, ret_type, ret_type_id); | |
2811 | if (err) | |
2812 | return err; | |
2813 | } | |
2814 | ||
2815 | /* Ensure the return type is a type that has a size */ | |
2816 | if (!btf_type_id_size(btf, &ret_type_id, NULL)) { | |
2817 | btf_verifier_log_type(env, t, "Invalid return type"); | |
2818 | return -EINVAL; | |
2819 | } | |
2820 | } | |
2821 | ||
2822 | if (!nr_args) | |
2823 | return 0; | |
2824 | ||
2825 | /* Last func arg type_id could be 0 if it is a vararg */ | |
2826 | if (!args[nr_args - 1].type) { | |
2827 | if (args[nr_args - 1].name_off) { | |
2828 | btf_verifier_log_type(env, t, "Invalid arg#%u", | |
2829 | nr_args); | |
2830 | return -EINVAL; | |
2831 | } | |
2832 | nr_args--; | |
2833 | } | |
2834 | ||
2835 | err = 0; | |
2836 | for (i = 0; i < nr_args; i++) { | |
2837 | const struct btf_type *arg_type; | |
2838 | u32 arg_type_id; | |
2839 | ||
2840 | arg_type_id = args[i].type; | |
2841 | arg_type = btf_type_by_id(btf, arg_type_id); | |
2842 | if (!arg_type) { | |
2843 | btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); | |
2844 | err = -EINVAL; | |
2845 | break; | |
2846 | } | |
2847 | ||
2848 | if (args[i].name_off && | |
2849 | (!btf_name_offset_valid(btf, args[i].name_off) || | |
2850 | !btf_name_valid_identifier(btf, args[i].name_off))) { | |
2851 | btf_verifier_log_type(env, t, | |
2852 | "Invalid arg#%u", i + 1); | |
2853 | err = -EINVAL; | |
2854 | break; | |
2855 | } | |
2856 | ||
2857 | if (btf_type_needs_resolve(arg_type) && | |
2858 | !env_type_is_resolved(env, arg_type_id)) { | |
2859 | err = btf_resolve(env, arg_type, arg_type_id); | |
2860 | if (err) | |
2861 | break; | |
2862 | } | |
2863 | ||
2864 | if (!btf_type_id_size(btf, &arg_type_id, NULL)) { | |
2865 | btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); | |
2866 | err = -EINVAL; | |
2867 | break; | |
2868 | } | |
2869 | } | |
2870 | ||
2871 | return err; | |
2872 | } | |
2873 | ||
2874 | static int btf_func_check(struct btf_verifier_env *env, | |
2875 | const struct btf_type *t) | |
2876 | { | |
2877 | const struct btf_type *proto_type; | |
2878 | const struct btf_param *args; | |
2879 | const struct btf *btf; | |
2880 | u16 nr_args, i; | |
2881 | ||
2882 | btf = env->btf; | |
2883 | proto_type = btf_type_by_id(btf, t->type); | |
2884 | ||
2885 | if (!proto_type || !btf_type_is_func_proto(proto_type)) { | |
2886 | btf_verifier_log_type(env, t, "Invalid type_id"); | |
2887 | return -EINVAL; | |
2888 | } | |
2889 | ||
2890 | args = (const struct btf_param *)(proto_type + 1); | |
2891 | nr_args = btf_type_vlen(proto_type); | |
2892 | for (i = 0; i < nr_args; i++) { | |
2893 | if (!args[i].name_off && args[i].type) { | |
2894 | btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); | |
2895 | return -EINVAL; | |
2896 | } | |
2897 | } | |
2898 | ||
2899 | return 0; | |
2900 | } | |
2901 | ||
69b693f0 MKL |
2902 | static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = { |
2903 | [BTF_KIND_INT] = &int_ops, | |
2904 | [BTF_KIND_PTR] = &ptr_ops, | |
2905 | [BTF_KIND_ARRAY] = &array_ops, | |
2906 | [BTF_KIND_STRUCT] = &struct_ops, | |
2907 | [BTF_KIND_UNION] = &struct_ops, | |
2908 | [BTF_KIND_ENUM] = &enum_ops, | |
2909 | [BTF_KIND_FWD] = &fwd_ops, | |
2910 | [BTF_KIND_TYPEDEF] = &modifier_ops, | |
2911 | [BTF_KIND_VOLATILE] = &modifier_ops, | |
2912 | [BTF_KIND_CONST] = &modifier_ops, | |
2913 | [BTF_KIND_RESTRICT] = &modifier_ops, | |
2667a262 MKL |
2914 | [BTF_KIND_FUNC] = &func_ops, |
2915 | [BTF_KIND_FUNC_PROTO] = &func_proto_ops, | |
1dc92851 DB |
2916 | [BTF_KIND_VAR] = &var_ops, |
2917 | [BTF_KIND_DATASEC] = &datasec_ops, | |
69b693f0 MKL |
2918 | }; |
2919 | ||
2920 | static s32 btf_check_meta(struct btf_verifier_env *env, | |
2921 | const struct btf_type *t, | |
2922 | u32 meta_left) | |
2923 | { | |
2924 | u32 saved_meta_left = meta_left; | |
2925 | s32 var_meta_size; | |
2926 | ||
2927 | if (meta_left < sizeof(*t)) { | |
2928 | btf_verifier_log(env, "[%u] meta_left:%u meta_needed:%zu", | |
2929 | env->log_type_id, meta_left, sizeof(*t)); | |
2930 | return -EINVAL; | |
2931 | } | |
2932 | meta_left -= sizeof(*t); | |
2933 | ||
aea2f7b8 MKL |
2934 | if (t->info & ~BTF_INFO_MASK) { |
2935 | btf_verifier_log(env, "[%u] Invalid btf_info:%x", | |
2936 | env->log_type_id, t->info); | |
2937 | return -EINVAL; | |
2938 | } | |
2939 | ||
69b693f0 MKL |
2940 | if (BTF_INFO_KIND(t->info) > BTF_KIND_MAX || |
2941 | BTF_INFO_KIND(t->info) == BTF_KIND_UNKN) { | |
2942 | btf_verifier_log(env, "[%u] Invalid kind:%u", | |
2943 | env->log_type_id, BTF_INFO_KIND(t->info)); | |
2944 | return -EINVAL; | |
2945 | } | |
2946 | ||
fbcf93eb | 2947 | if (!btf_name_offset_valid(env->btf, t->name_off)) { |
69b693f0 | 2948 | btf_verifier_log(env, "[%u] Invalid name_offset:%u", |
fbcf93eb | 2949 | env->log_type_id, t->name_off); |
69b693f0 MKL |
2950 | return -EINVAL; |
2951 | } | |
2952 | ||
2953 | var_meta_size = btf_type_ops(t)->check_meta(env, t, meta_left); | |
2954 | if (var_meta_size < 0) | |
2955 | return var_meta_size; | |
2956 | ||
2957 | meta_left -= var_meta_size; | |
2958 | ||
2959 | return saved_meta_left - meta_left; | |
2960 | } | |
2961 | ||
2962 | static int btf_check_all_metas(struct btf_verifier_env *env) | |
2963 | { | |
2964 | struct btf *btf = env->btf; | |
2965 | struct btf_header *hdr; | |
2966 | void *cur, *end; | |
2967 | ||
f80442a4 | 2968 | hdr = &btf->hdr; |
69b693f0 | 2969 | cur = btf->nohdr_data + hdr->type_off; |
4b1c5d91 | 2970 | end = cur + hdr->type_len; |
69b693f0 MKL |
2971 | |
2972 | env->log_type_id = 1; | |
2973 | while (cur < end) { | |
2974 | struct btf_type *t = cur; | |
2975 | s32 meta_size; | |
2976 | ||
2977 | meta_size = btf_check_meta(env, t, end - cur); | |
2978 | if (meta_size < 0) | |
2979 | return meta_size; | |
2980 | ||
2981 | btf_add_type(env, t); | |
2982 | cur += meta_size; | |
2983 | env->log_type_id++; | |
2984 | } | |
2985 | ||
2986 | return 0; | |
2987 | } | |
2988 | ||
eb3f595d MKL |
2989 | static bool btf_resolve_valid(struct btf_verifier_env *env, |
2990 | const struct btf_type *t, | |
2991 | u32 type_id) | |
2992 | { | |
2993 | struct btf *btf = env->btf; | |
2994 | ||
2995 | if (!env_type_is_resolved(env, type_id)) | |
2996 | return false; | |
2997 | ||
1dc92851 | 2998 | if (btf_type_is_struct(t) || btf_type_is_datasec(t)) |
eb3f595d | 2999 | return !btf->resolved_ids[type_id] && |
1dc92851 | 3000 | !btf->resolved_sizes[type_id]; |
eb3f595d | 3001 | |
1dc92851 DB |
3002 | if (btf_type_is_modifier(t) || btf_type_is_ptr(t) || |
3003 | btf_type_is_var(t)) { | |
eb3f595d | 3004 | t = btf_type_id_resolve(btf, &type_id); |
1dc92851 DB |
3005 | return t && |
3006 | !btf_type_is_modifier(t) && | |
3007 | !btf_type_is_var(t) && | |
3008 | !btf_type_is_datasec(t); | |
eb3f595d MKL |
3009 | } |
3010 | ||
3011 | if (btf_type_is_array(t)) { | |
3012 | const struct btf_array *array = btf_type_array(t); | |
3013 | const struct btf_type *elem_type; | |
3014 | u32 elem_type_id = array->type; | |
3015 | u32 elem_size; | |
3016 | ||
3017 | elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size); | |
3018 | return elem_type && !btf_type_is_modifier(elem_type) && | |
3019 | (array->nelems * elem_size == | |
3020 | btf->resolved_sizes[type_id]); | |
3021 | } | |
3022 | ||
3023 | return false; | |
3024 | } | |
3025 | ||
2667a262 MKL |
3026 | static int btf_resolve(struct btf_verifier_env *env, |
3027 | const struct btf_type *t, u32 type_id) | |
3028 | { | |
3029 | u32 save_log_type_id = env->log_type_id; | |
3030 | const struct resolve_vertex *v; | |
3031 | int err = 0; | |
3032 | ||
3033 | env->resolve_mode = RESOLVE_TBD; | |
3034 | env_stack_push(env, t, type_id); | |
3035 | while (!err && (v = env_stack_peak(env))) { | |
3036 | env->log_type_id = v->type_id; | |
3037 | err = btf_type_ops(v->t)->resolve(env, v); | |
3038 | } | |
3039 | ||
3040 | env->log_type_id = type_id; | |
3041 | if (err == -E2BIG) { | |
3042 | btf_verifier_log_type(env, t, | |
3043 | "Exceeded max resolving depth:%u", | |
3044 | MAX_RESOLVE_DEPTH); | |
3045 | } else if (err == -EEXIST) { | |
3046 | btf_verifier_log_type(env, t, "Loop detected"); | |
3047 | } | |
3048 | ||
3049 | /* Final sanity check */ | |
3050 | if (!err && !btf_resolve_valid(env, t, type_id)) { | |
3051 | btf_verifier_log_type(env, t, "Invalid resolve state"); | |
3052 | err = -EINVAL; | |
3053 | } | |
3054 | ||
3055 | env->log_type_id = save_log_type_id; | |
3056 | return err; | |
3057 | } | |
3058 | ||
eb3f595d MKL |
3059 | static int btf_check_all_types(struct btf_verifier_env *env) |
3060 | { | |
3061 | struct btf *btf = env->btf; | |
3062 | u32 type_id; | |
3063 | int err; | |
3064 | ||
3065 | err = env_resolve_init(env); | |
3066 | if (err) | |
3067 | return err; | |
3068 | ||
3069 | env->phase++; | |
3070 | for (type_id = 1; type_id <= btf->nr_types; type_id++) { | |
3071 | const struct btf_type *t = btf_type_by_id(btf, type_id); | |
3072 | ||
3073 | env->log_type_id = type_id; | |
3074 | if (btf_type_needs_resolve(t) && | |
3075 | !env_type_is_resolved(env, type_id)) { | |
3076 | err = btf_resolve(env, t, type_id); | |
3077 | if (err) | |
3078 | return err; | |
3079 | } | |
3080 | ||
2667a262 MKL |
3081 | if (btf_type_is_func_proto(t)) { |
3082 | err = btf_func_proto_check(env, t); | |
3083 | if (err) | |
3084 | return err; | |
3085 | } | |
3086 | ||
3087 | if (btf_type_is_func(t)) { | |
3088 | err = btf_func_check(env, t); | |
3089 | if (err) | |
3090 | return err; | |
eb3f595d MKL |
3091 | } |
3092 | } | |
3093 | ||
3094 | return 0; | |
3095 | } | |
3096 | ||
69b693f0 MKL |
3097 | static int btf_parse_type_sec(struct btf_verifier_env *env) |
3098 | { | |
f80442a4 | 3099 | const struct btf_header *hdr = &env->btf->hdr; |
eb3f595d MKL |
3100 | int err; |
3101 | ||
f80442a4 MKL |
3102 | /* Type section must align to 4 bytes */ |
3103 | if (hdr->type_off & (sizeof(u32) - 1)) { | |
3104 | btf_verifier_log(env, "Unaligned type_off"); | |
3105 | return -EINVAL; | |
3106 | } | |
3107 | ||
3108 | if (!hdr->type_len) { | |
3109 | btf_verifier_log(env, "No type found"); | |
3110 | return -EINVAL; | |
3111 | } | |
3112 | ||
eb3f595d MKL |
3113 | err = btf_check_all_metas(env); |
3114 | if (err) | |
3115 | return err; | |
3116 | ||
3117 | return btf_check_all_types(env); | |
69b693f0 MKL |
3118 | } |
3119 | ||
3120 | static int btf_parse_str_sec(struct btf_verifier_env *env) | |
3121 | { | |
3122 | const struct btf_header *hdr; | |
3123 | struct btf *btf = env->btf; | |
3124 | const char *start, *end; | |
3125 | ||
f80442a4 | 3126 | hdr = &btf->hdr; |
69b693f0 MKL |
3127 | start = btf->nohdr_data + hdr->str_off; |
3128 | end = start + hdr->str_len; | |
3129 | ||
f80442a4 MKL |
3130 | if (end != btf->data + btf->data_size) { |
3131 | btf_verifier_log(env, "String section is not at the end"); | |
3132 | return -EINVAL; | |
3133 | } | |
3134 | ||
69b693f0 MKL |
3135 | if (!hdr->str_len || hdr->str_len - 1 > BTF_MAX_NAME_OFFSET || |
3136 | start[0] || end[-1]) { | |
3137 | btf_verifier_log(env, "Invalid string section"); | |
3138 | return -EINVAL; | |
3139 | } | |
3140 | ||
3141 | btf->strings = start; | |
3142 | ||
3143 | return 0; | |
3144 | } | |
3145 | ||
f80442a4 MKL |
3146 | static const size_t btf_sec_info_offset[] = { |
3147 | offsetof(struct btf_header, type_off), | |
3148 | offsetof(struct btf_header, str_off), | |
3149 | }; | |
3150 | ||
3151 | static int btf_sec_info_cmp(const void *a, const void *b) | |
69b693f0 | 3152 | { |
f80442a4 MKL |
3153 | const struct btf_sec_info *x = a; |
3154 | const struct btf_sec_info *y = b; | |
3155 | ||
3156 | return (int)(x->off - y->off) ? : (int)(x->len - y->len); | |
3157 | } | |
3158 | ||
3159 | static int btf_check_sec_info(struct btf_verifier_env *env, | |
3160 | u32 btf_data_size) | |
3161 | { | |
a2889a4c | 3162 | struct btf_sec_info secs[ARRAY_SIZE(btf_sec_info_offset)]; |
f80442a4 | 3163 | u32 total, expected_total, i; |
69b693f0 | 3164 | const struct btf_header *hdr; |
f80442a4 MKL |
3165 | const struct btf *btf; |
3166 | ||
3167 | btf = env->btf; | |
3168 | hdr = &btf->hdr; | |
3169 | ||
3170 | /* Populate the secs from hdr */ | |
a2889a4c | 3171 | for (i = 0; i < ARRAY_SIZE(btf_sec_info_offset); i++) |
f80442a4 MKL |
3172 | secs[i] = *(struct btf_sec_info *)((void *)hdr + |
3173 | btf_sec_info_offset[i]); | |
3174 | ||
a2889a4c MKL |
3175 | sort(secs, ARRAY_SIZE(btf_sec_info_offset), |
3176 | sizeof(struct btf_sec_info), btf_sec_info_cmp, NULL); | |
f80442a4 MKL |
3177 | |
3178 | /* Check for gaps and overlap among sections */ | |
3179 | total = 0; | |
3180 | expected_total = btf_data_size - hdr->hdr_len; | |
a2889a4c | 3181 | for (i = 0; i < ARRAY_SIZE(btf_sec_info_offset); i++) { |
f80442a4 MKL |
3182 | if (expected_total < secs[i].off) { |
3183 | btf_verifier_log(env, "Invalid section offset"); | |
3184 | return -EINVAL; | |
3185 | } | |
3186 | if (total < secs[i].off) { | |
3187 | /* gap */ | |
3188 | btf_verifier_log(env, "Unsupported section found"); | |
3189 | return -EINVAL; | |
3190 | } | |
3191 | if (total > secs[i].off) { | |
3192 | btf_verifier_log(env, "Section overlap found"); | |
3193 | return -EINVAL; | |
3194 | } | |
3195 | if (expected_total - total < secs[i].len) { | |
3196 | btf_verifier_log(env, | |
3197 | "Total section length too long"); | |
3198 | return -EINVAL; | |
3199 | } | |
3200 | total += secs[i].len; | |
3201 | } | |
3202 | ||
3203 | /* There is data other than hdr and known sections */ | |
3204 | if (expected_total != total) { | |
3205 | btf_verifier_log(env, "Unsupported section found"); | |
3206 | return -EINVAL; | |
3207 | } | |
3208 | ||
3209 | return 0; | |
3210 | } | |
3211 | ||
4a6998af | 3212 | static int btf_parse_hdr(struct btf_verifier_env *env) |
f80442a4 | 3213 | { |
4a6998af | 3214 | u32 hdr_len, hdr_copy, btf_data_size; |
f80442a4 | 3215 | const struct btf_header *hdr; |
f80442a4 MKL |
3216 | struct btf *btf; |
3217 | int err; | |
69b693f0 | 3218 | |
f80442a4 | 3219 | btf = env->btf; |
4a6998af | 3220 | btf_data_size = btf->data_size; |
f80442a4 | 3221 | |
4a6998af ML |
3222 | if (btf_data_size < |
3223 | offsetof(struct btf_header, hdr_len) + sizeof(hdr->hdr_len)) { | |
f80442a4 MKL |
3224 | btf_verifier_log(env, "hdr_len not found"); |
3225 | return -EINVAL; | |
3226 | } | |
3227 | ||
4a6998af ML |
3228 | hdr = btf->data; |
3229 | hdr_len = hdr->hdr_len; | |
f80442a4 | 3230 | if (btf_data_size < hdr_len) { |
69b693f0 MKL |
3231 | btf_verifier_log(env, "btf_header not found"); |
3232 | return -EINVAL; | |
3233 | } | |
3234 | ||
4a6998af ML |
3235 | /* Ensure the unsupported header fields are zero */ |
3236 | if (hdr_len > sizeof(btf->hdr)) { | |
3237 | u8 *expected_zero = btf->data + sizeof(btf->hdr); | |
3238 | u8 *end = btf->data + hdr_len; | |
3239 | ||
3240 | for (; expected_zero < end; expected_zero++) { | |
3241 | if (*expected_zero) { | |
3242 | btf_verifier_log(env, "Unsupported btf_header"); | |
3243 | return -E2BIG; | |
3244 | } | |
3245 | } | |
f80442a4 MKL |
3246 | } |
3247 | ||
3248 | hdr_copy = min_t(u32, hdr_len, sizeof(btf->hdr)); | |
4a6998af | 3249 | memcpy(&btf->hdr, btf->data, hdr_copy); |
f80442a4 MKL |
3250 | |
3251 | hdr = &btf->hdr; | |
3252 | ||
3253 | btf_verifier_log_hdr(env, btf_data_size); | |
69b693f0 | 3254 | |
69b693f0 MKL |
3255 | if (hdr->magic != BTF_MAGIC) { |
3256 | btf_verifier_log(env, "Invalid magic"); | |
3257 | return -EINVAL; | |
3258 | } | |
3259 | ||
3260 | if (hdr->version != BTF_VERSION) { | |
3261 | btf_verifier_log(env, "Unsupported version"); | |
3262 | return -ENOTSUPP; | |
3263 | } | |
3264 | ||
3265 | if (hdr->flags) { | |
3266 | btf_verifier_log(env, "Unsupported flags"); | |
3267 | return -ENOTSUPP; | |
3268 | } | |
3269 | ||
f80442a4 | 3270 | if (btf_data_size == hdr->hdr_len) { |
69b693f0 MKL |
3271 | btf_verifier_log(env, "No data"); |
3272 | return -EINVAL; | |
3273 | } | |
3274 | ||
f80442a4 MKL |
3275 | err = btf_check_sec_info(env, btf_data_size); |
3276 | if (err) | |
3277 | return err; | |
69b693f0 MKL |
3278 | |
3279 | return 0; | |
3280 | } | |
3281 | ||
3282 | static struct btf *btf_parse(void __user *btf_data, u32 btf_data_size, | |
3283 | u32 log_level, char __user *log_ubuf, u32 log_size) | |
3284 | { | |
3285 | struct btf_verifier_env *env = NULL; | |
3286 | struct bpf_verifier_log *log; | |
3287 | struct btf *btf = NULL; | |
3288 | u8 *data; | |
3289 | int err; | |
3290 | ||
3291 | if (btf_data_size > BTF_MAX_SIZE) | |
3292 | return ERR_PTR(-E2BIG); | |
3293 | ||
3294 | env = kzalloc(sizeof(*env), GFP_KERNEL | __GFP_NOWARN); | |
3295 | if (!env) | |
3296 | return ERR_PTR(-ENOMEM); | |
3297 | ||
3298 | log = &env->log; | |
3299 | if (log_level || log_ubuf || log_size) { | |
3300 | /* user requested verbose verifier output | |
3301 | * and supplied buffer to store the verification trace | |
3302 | */ | |
3303 | log->level = log_level; | |
3304 | log->ubuf = log_ubuf; | |
3305 | log->len_total = log_size; | |
3306 | ||
3307 | /* log attributes have to be sane */ | |
3308 | if (log->len_total < 128 || log->len_total > UINT_MAX >> 8 || | |
3309 | !log->level || !log->ubuf) { | |
3310 | err = -EINVAL; | |
3311 | goto errout; | |
3312 | } | |
3313 | } | |
3314 | ||
3315 | btf = kzalloc(sizeof(*btf), GFP_KERNEL | __GFP_NOWARN); | |
3316 | if (!btf) { | |
3317 | err = -ENOMEM; | |
3318 | goto errout; | |
3319 | } | |
f80442a4 MKL |
3320 | env->btf = btf; |
3321 | ||
69b693f0 MKL |
3322 | data = kvmalloc(btf_data_size, GFP_KERNEL | __GFP_NOWARN); |
3323 | if (!data) { | |
3324 | err = -ENOMEM; | |
3325 | goto errout; | |
3326 | } | |
3327 | ||
3328 | btf->data = data; | |
3329 | btf->data_size = btf_data_size; | |
3330 | ||
3331 | if (copy_from_user(data, btf_data, btf_data_size)) { | |
3332 | err = -EFAULT; | |
3333 | goto errout; | |
3334 | } | |
3335 | ||
4a6998af ML |
3336 | err = btf_parse_hdr(env); |
3337 | if (err) | |
3338 | goto errout; | |
3339 | ||
3340 | btf->nohdr_data = btf->data + btf->hdr.hdr_len; | |
3341 | ||
69b693f0 MKL |
3342 | err = btf_parse_str_sec(env); |
3343 | if (err) | |
3344 | goto errout; | |
3345 | ||
3346 | err = btf_parse_type_sec(env); | |
3347 | if (err) | |
3348 | goto errout; | |
3349 | ||
f80442a4 | 3350 | if (log->level && bpf_verifier_log_full(log)) { |
69b693f0 MKL |
3351 | err = -ENOSPC; |
3352 | goto errout; | |
3353 | } | |
3354 | ||
f80442a4 MKL |
3355 | btf_verifier_env_free(env); |
3356 | refcount_set(&btf->refcnt, 1); | |
3357 | return btf; | |
69b693f0 MKL |
3358 | |
3359 | errout: | |
3360 | btf_verifier_env_free(env); | |
3361 | if (btf) | |
3362 | btf_free(btf); | |
3363 | return ERR_PTR(err); | |
3364 | } | |
b00b8dae MKL |
3365 | |
3366 | void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj, | |
3367 | struct seq_file *m) | |
3368 | { | |
3369 | const struct btf_type *t = btf_type_by_id(btf, type_id); | |
3370 | ||
3371 | btf_type_ops(t)->seq_show(btf, t, type_id, obj, 0, m); | |
3372 | } | |
f56a653c MKL |
3373 | |
3374 | static int btf_release(struct inode *inode, struct file *filp) | |
3375 | { | |
3376 | btf_put(filp->private_data); | |
3377 | return 0; | |
3378 | } | |
3379 | ||
60197cfb | 3380 | const struct file_operations btf_fops = { |
f56a653c MKL |
3381 | .release = btf_release, |
3382 | }; | |
3383 | ||
78958fca MKL |
3384 | static int __btf_new_fd(struct btf *btf) |
3385 | { | |
3386 | return anon_inode_getfd("btf", &btf_fops, btf, O_RDONLY | O_CLOEXEC); | |
3387 | } | |
3388 | ||
f56a653c MKL |
3389 | int btf_new_fd(const union bpf_attr *attr) |
3390 | { | |
3391 | struct btf *btf; | |
78958fca | 3392 | int ret; |
f56a653c MKL |
3393 | |
3394 | btf = btf_parse(u64_to_user_ptr(attr->btf), | |
3395 | attr->btf_size, attr->btf_log_level, | |
3396 | u64_to_user_ptr(attr->btf_log_buf), | |
3397 | attr->btf_log_size); | |
3398 | if (IS_ERR(btf)) | |
3399 | return PTR_ERR(btf); | |
3400 | ||
78958fca MKL |
3401 | ret = btf_alloc_id(btf); |
3402 | if (ret) { | |
3403 | btf_free(btf); | |
3404 | return ret; | |
3405 | } | |
3406 | ||
3407 | /* | |
3408 | * The BTF ID is published to the userspace. | |
3409 | * All BTF free must go through call_rcu() from | |
3410 | * now on (i.e. free by calling btf_put()). | |
3411 | */ | |
3412 | ||
3413 | ret = __btf_new_fd(btf); | |
3414 | if (ret < 0) | |
f56a653c MKL |
3415 | btf_put(btf); |
3416 | ||
78958fca | 3417 | return ret; |
f56a653c MKL |
3418 | } |
3419 | ||
3420 | struct btf *btf_get_by_fd(int fd) | |
3421 | { | |
3422 | struct btf *btf; | |
3423 | struct fd f; | |
3424 | ||
3425 | f = fdget(fd); | |
3426 | ||
3427 | if (!f.file) | |
3428 | return ERR_PTR(-EBADF); | |
3429 | ||
3430 | if (f.file->f_op != &btf_fops) { | |
3431 | fdput(f); | |
3432 | return ERR_PTR(-EINVAL); | |
3433 | } | |
3434 | ||
3435 | btf = f.file->private_data; | |
78958fca | 3436 | refcount_inc(&btf->refcnt); |
f56a653c MKL |
3437 | fdput(f); |
3438 | ||
3439 | return btf; | |
3440 | } | |
60197cfb MKL |
3441 | |
3442 | int btf_get_info_by_fd(const struct btf *btf, | |
3443 | const union bpf_attr *attr, | |
3444 | union bpf_attr __user *uattr) | |
3445 | { | |
62dab84c MKL |
3446 | struct bpf_btf_info __user *uinfo; |
3447 | struct bpf_btf_info info = {}; | |
3448 | u32 info_copy, btf_copy; | |
3449 | void __user *ubtf; | |
3450 | u32 uinfo_len; | |
60197cfb | 3451 | |
62dab84c MKL |
3452 | uinfo = u64_to_user_ptr(attr->info.info); |
3453 | uinfo_len = attr->info.info_len; | |
3454 | ||
3455 | info_copy = min_t(u32, uinfo_len, sizeof(info)); | |
3456 | if (copy_from_user(&info, uinfo, info_copy)) | |
3457 | return -EFAULT; | |
3458 | ||
3459 | info.id = btf->id; | |
3460 | ubtf = u64_to_user_ptr(info.btf); | |
3461 | btf_copy = min_t(u32, btf->data_size, info.btf_size); | |
3462 | if (copy_to_user(ubtf, btf->data, btf_copy)) | |
3463 | return -EFAULT; | |
3464 | info.btf_size = btf->data_size; | |
3465 | ||
3466 | if (copy_to_user(uinfo, &info, info_copy) || | |
3467 | put_user(info_copy, &uattr->info.info_len)) | |
60197cfb MKL |
3468 | return -EFAULT; |
3469 | ||
3470 | return 0; | |
3471 | } | |
78958fca MKL |
3472 | |
3473 | int btf_get_fd_by_id(u32 id) | |
3474 | { | |
3475 | struct btf *btf; | |
3476 | int fd; | |
3477 | ||
3478 | rcu_read_lock(); | |
3479 | btf = idr_find(&btf_idr, id); | |
3480 | if (!btf || !refcount_inc_not_zero(&btf->refcnt)) | |
3481 | btf = ERR_PTR(-ENOENT); | |
3482 | rcu_read_unlock(); | |
3483 | ||
3484 | if (IS_ERR(btf)) | |
3485 | return PTR_ERR(btf); | |
3486 | ||
3487 | fd = __btf_new_fd(btf); | |
3488 | if (fd < 0) | |
3489 | btf_put(btf); | |
3490 | ||
3491 | return fd; | |
3492 | } | |
3493 | ||
3494 | u32 btf_id(const struct btf *btf) | |
3495 | { | |
3496 | return btf->id; | |
3497 | } |