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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 | ||
1b9ed84e QM |
198 | DEFINE_IDR(btf_idr); |
199 | DEFINE_SPINLOCK(btf_idr_lock); | |
78958fca | 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 | ||
eb3f595d MKL |
1076 | size_type_id = btf->resolved_ids[size_type_id]; |
1077 | size_type = btf_type_by_id(btf, size_type_id); | |
b47a0bd2 | 1078 | if (btf_type_nosize_or_null(size_type)) |
eb3f595d | 1079 | return NULL; |
1acc5d5c AN |
1080 | else if (btf_type_has_size(size_type)) |
1081 | size = size_type->size; | |
1082 | else if (btf_type_is_array(size_type)) | |
1083 | size = btf->resolved_sizes[size_type_id]; | |
1084 | else if (btf_type_is_ptr(size_type)) | |
1085 | size = sizeof(void *); | |
1086 | else | |
1087 | return NULL; | |
eb3f595d MKL |
1088 | } |
1089 | ||
1090 | *type_id = size_type_id; | |
1091 | if (ret_size) | |
1092 | *ret_size = size; | |
1093 | ||
1094 | return size_type; | |
1095 | } | |
1096 | ||
179cde8c MKL |
1097 | static int btf_df_check_member(struct btf_verifier_env *env, |
1098 | const struct btf_type *struct_type, | |
1099 | const struct btf_member *member, | |
1100 | const struct btf_type *member_type) | |
1101 | { | |
1102 | btf_verifier_log_basic(env, struct_type, | |
1103 | "Unsupported check_member"); | |
1104 | return -EINVAL; | |
1105 | } | |
1106 | ||
9d5f9f70 YS |
1107 | static int btf_df_check_kflag_member(struct btf_verifier_env *env, |
1108 | const struct btf_type *struct_type, | |
1109 | const struct btf_member *member, | |
1110 | const struct btf_type *member_type) | |
1111 | { | |
1112 | btf_verifier_log_basic(env, struct_type, | |
1113 | "Unsupported check_kflag_member"); | |
1114 | return -EINVAL; | |
1115 | } | |
1116 | ||
1117 | /* Used for ptr, array and struct/union type members. | |
1118 | * int, enum and modifier types have their specific callback functions. | |
1119 | */ | |
1120 | static int btf_generic_check_kflag_member(struct btf_verifier_env *env, | |
1121 | const struct btf_type *struct_type, | |
1122 | const struct btf_member *member, | |
1123 | const struct btf_type *member_type) | |
1124 | { | |
1125 | if (BTF_MEMBER_BITFIELD_SIZE(member->offset)) { | |
1126 | btf_verifier_log_member(env, struct_type, member, | |
1127 | "Invalid member bitfield_size"); | |
1128 | return -EINVAL; | |
1129 | } | |
1130 | ||
1131 | /* bitfield size is 0, so member->offset represents bit offset only. | |
1132 | * It is safe to call non kflag check_member variants. | |
1133 | */ | |
1134 | return btf_type_ops(member_type)->check_member(env, struct_type, | |
1135 | member, | |
1136 | member_type); | |
1137 | } | |
1138 | ||
eb3f595d MKL |
1139 | static int btf_df_resolve(struct btf_verifier_env *env, |
1140 | const struct resolve_vertex *v) | |
1141 | { | |
1142 | btf_verifier_log_basic(env, v->t, "Unsupported resolve"); | |
1143 | return -EINVAL; | |
1144 | } | |
1145 | ||
b00b8dae MKL |
1146 | static void btf_df_seq_show(const struct btf *btf, const struct btf_type *t, |
1147 | u32 type_id, void *data, u8 bits_offsets, | |
1148 | struct seq_file *m) | |
1149 | { | |
1150 | seq_printf(m, "<unsupported kind:%u>", BTF_INFO_KIND(t->info)); | |
1151 | } | |
1152 | ||
179cde8c MKL |
1153 | static int btf_int_check_member(struct btf_verifier_env *env, |
1154 | const struct btf_type *struct_type, | |
1155 | const struct btf_member *member, | |
1156 | const struct btf_type *member_type) | |
1157 | { | |
1158 | u32 int_data = btf_type_int(member_type); | |
1159 | u32 struct_bits_off = member->offset; | |
1160 | u32 struct_size = struct_type->size; | |
1161 | u32 nr_copy_bits; | |
1162 | u32 bytes_offset; | |
1163 | ||
1164 | if (U32_MAX - struct_bits_off < BTF_INT_OFFSET(int_data)) { | |
1165 | btf_verifier_log_member(env, struct_type, member, | |
1166 | "bits_offset exceeds U32_MAX"); | |
1167 | return -EINVAL; | |
1168 | } | |
1169 | ||
1170 | struct_bits_off += BTF_INT_OFFSET(int_data); | |
1171 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
1172 | nr_copy_bits = BTF_INT_BITS(int_data) + | |
1173 | BITS_PER_BYTE_MASKED(struct_bits_off); | |
1174 | ||
b1e8818c | 1175 | if (nr_copy_bits > BITS_PER_U128) { |
179cde8c | 1176 | btf_verifier_log_member(env, struct_type, member, |
b1e8818c | 1177 | "nr_copy_bits exceeds 128"); |
179cde8c MKL |
1178 | return -EINVAL; |
1179 | } | |
1180 | ||
1181 | if (struct_size < bytes_offset || | |
1182 | struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) { | |
1183 | btf_verifier_log_member(env, struct_type, member, | |
1184 | "Member exceeds struct_size"); | |
1185 | return -EINVAL; | |
1186 | } | |
1187 | ||
1188 | return 0; | |
1189 | } | |
1190 | ||
9d5f9f70 YS |
1191 | static int btf_int_check_kflag_member(struct btf_verifier_env *env, |
1192 | const struct btf_type *struct_type, | |
1193 | const struct btf_member *member, | |
1194 | const struct btf_type *member_type) | |
1195 | { | |
1196 | u32 struct_bits_off, nr_bits, nr_int_data_bits, bytes_offset; | |
1197 | u32 int_data = btf_type_int(member_type); | |
1198 | u32 struct_size = struct_type->size; | |
1199 | u32 nr_copy_bits; | |
1200 | ||
1201 | /* a regular int type is required for the kflag int member */ | |
1202 | if (!btf_type_int_is_regular(member_type)) { | |
1203 | btf_verifier_log_member(env, struct_type, member, | |
1204 | "Invalid member base type"); | |
1205 | return -EINVAL; | |
1206 | } | |
1207 | ||
1208 | /* check sanity of bitfield size */ | |
1209 | nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset); | |
1210 | struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset); | |
1211 | nr_int_data_bits = BTF_INT_BITS(int_data); | |
1212 | if (!nr_bits) { | |
1213 | /* Not a bitfield member, member offset must be at byte | |
1214 | * boundary. | |
1215 | */ | |
1216 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
1217 | btf_verifier_log_member(env, struct_type, member, | |
1218 | "Invalid member offset"); | |
1219 | return -EINVAL; | |
1220 | } | |
1221 | ||
1222 | nr_bits = nr_int_data_bits; | |
1223 | } else if (nr_bits > nr_int_data_bits) { | |
1224 | btf_verifier_log_member(env, struct_type, member, | |
1225 | "Invalid member bitfield_size"); | |
1226 | return -EINVAL; | |
1227 | } | |
1228 | ||
1229 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
1230 | nr_copy_bits = nr_bits + BITS_PER_BYTE_MASKED(struct_bits_off); | |
b1e8818c | 1231 | if (nr_copy_bits > BITS_PER_U128) { |
9d5f9f70 | 1232 | btf_verifier_log_member(env, struct_type, member, |
b1e8818c | 1233 | "nr_copy_bits exceeds 128"); |
9d5f9f70 YS |
1234 | return -EINVAL; |
1235 | } | |
1236 | ||
1237 | if (struct_size < bytes_offset || | |
1238 | struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) { | |
1239 | btf_verifier_log_member(env, struct_type, member, | |
1240 | "Member exceeds struct_size"); | |
1241 | return -EINVAL; | |
1242 | } | |
1243 | ||
1244 | return 0; | |
1245 | } | |
1246 | ||
69b693f0 MKL |
1247 | static s32 btf_int_check_meta(struct btf_verifier_env *env, |
1248 | const struct btf_type *t, | |
1249 | u32 meta_left) | |
1250 | { | |
1251 | u32 int_data, nr_bits, meta_needed = sizeof(int_data); | |
1252 | u16 encoding; | |
1253 | ||
1254 | if (meta_left < meta_needed) { | |
1255 | btf_verifier_log_basic(env, t, | |
1256 | "meta_left:%u meta_needed:%u", | |
1257 | meta_left, meta_needed); | |
1258 | return -EINVAL; | |
1259 | } | |
1260 | ||
1261 | if (btf_type_vlen(t)) { | |
1262 | btf_verifier_log_type(env, t, "vlen != 0"); | |
1263 | return -EINVAL; | |
1264 | } | |
1265 | ||
9d5f9f70 YS |
1266 | if (btf_type_kflag(t)) { |
1267 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
1268 | return -EINVAL; | |
1269 | } | |
1270 | ||
69b693f0 | 1271 | int_data = btf_type_int(t); |
aea2f7b8 MKL |
1272 | if (int_data & ~BTF_INT_MASK) { |
1273 | btf_verifier_log_basic(env, t, "Invalid int_data:%x", | |
1274 | int_data); | |
1275 | return -EINVAL; | |
1276 | } | |
1277 | ||
69b693f0 MKL |
1278 | nr_bits = BTF_INT_BITS(int_data) + BTF_INT_OFFSET(int_data); |
1279 | ||
b1e8818c | 1280 | if (nr_bits > BITS_PER_U128) { |
69b693f0 | 1281 | btf_verifier_log_type(env, t, "nr_bits exceeds %zu", |
b1e8818c | 1282 | BITS_PER_U128); |
69b693f0 MKL |
1283 | return -EINVAL; |
1284 | } | |
1285 | ||
1286 | if (BITS_ROUNDUP_BYTES(nr_bits) > t->size) { | |
1287 | btf_verifier_log_type(env, t, "nr_bits exceeds type_size"); | |
1288 | return -EINVAL; | |
1289 | } | |
1290 | ||
aea2f7b8 MKL |
1291 | /* |
1292 | * Only one of the encoding bits is allowed and it | |
1293 | * should be sufficient for the pretty print purpose (i.e. decoding). | |
1294 | * Multiple bits can be allowed later if it is found | |
1295 | * to be insufficient. | |
1296 | */ | |
69b693f0 MKL |
1297 | encoding = BTF_INT_ENCODING(int_data); |
1298 | if (encoding && | |
1299 | encoding != BTF_INT_SIGNED && | |
1300 | encoding != BTF_INT_CHAR && | |
aea2f7b8 | 1301 | encoding != BTF_INT_BOOL) { |
69b693f0 MKL |
1302 | btf_verifier_log_type(env, t, "Unsupported encoding"); |
1303 | return -ENOTSUPP; | |
1304 | } | |
1305 | ||
1306 | btf_verifier_log_type(env, t, NULL); | |
1307 | ||
1308 | return meta_needed; | |
1309 | } | |
1310 | ||
1311 | static void btf_int_log(struct btf_verifier_env *env, | |
1312 | const struct btf_type *t) | |
1313 | { | |
1314 | int int_data = btf_type_int(t); | |
1315 | ||
1316 | btf_verifier_log(env, | |
1317 | "size=%u bits_offset=%u nr_bits=%u encoding=%s", | |
1318 | t->size, BTF_INT_OFFSET(int_data), | |
1319 | BTF_INT_BITS(int_data), | |
1320 | btf_int_encoding_str(BTF_INT_ENCODING(int_data))); | |
1321 | } | |
1322 | ||
b1e8818c YS |
1323 | static void btf_int128_print(struct seq_file *m, void *data) |
1324 | { | |
1325 | /* data points to a __int128 number. | |
1326 | * Suppose | |
1327 | * int128_num = *(__int128 *)data; | |
1328 | * The below formulas shows what upper_num and lower_num represents: | |
1329 | * upper_num = int128_num >> 64; | |
1330 | * lower_num = int128_num & 0xffffffffFFFFFFFFULL; | |
1331 | */ | |
1332 | u64 upper_num, lower_num; | |
1333 | ||
1334 | #ifdef __BIG_ENDIAN_BITFIELD | |
1335 | upper_num = *(u64 *)data; | |
1336 | lower_num = *(u64 *)(data + 8); | |
1337 | #else | |
1338 | upper_num = *(u64 *)(data + 8); | |
1339 | lower_num = *(u64 *)data; | |
1340 | #endif | |
1341 | if (upper_num == 0) | |
1342 | seq_printf(m, "0x%llx", lower_num); | |
1343 | else | |
1344 | seq_printf(m, "0x%llx%016llx", upper_num, lower_num); | |
1345 | } | |
1346 | ||
1347 | static void btf_int128_shift(u64 *print_num, u16 left_shift_bits, | |
1348 | u16 right_shift_bits) | |
1349 | { | |
1350 | u64 upper_num, lower_num; | |
1351 | ||
1352 | #ifdef __BIG_ENDIAN_BITFIELD | |
1353 | upper_num = print_num[0]; | |
1354 | lower_num = print_num[1]; | |
1355 | #else | |
1356 | upper_num = print_num[1]; | |
1357 | lower_num = print_num[0]; | |
1358 | #endif | |
1359 | ||
1360 | /* shake out un-needed bits by shift/or operations */ | |
1361 | if (left_shift_bits >= 64) { | |
1362 | upper_num = lower_num << (left_shift_bits - 64); | |
1363 | lower_num = 0; | |
1364 | } else { | |
1365 | upper_num = (upper_num << left_shift_bits) | | |
1366 | (lower_num >> (64 - left_shift_bits)); | |
1367 | lower_num = lower_num << left_shift_bits; | |
1368 | } | |
1369 | ||
1370 | if (right_shift_bits >= 64) { | |
1371 | lower_num = upper_num >> (right_shift_bits - 64); | |
1372 | upper_num = 0; | |
1373 | } else { | |
1374 | lower_num = (lower_num >> right_shift_bits) | | |
1375 | (upper_num << (64 - right_shift_bits)); | |
1376 | upper_num = upper_num >> right_shift_bits; | |
1377 | } | |
1378 | ||
1379 | #ifdef __BIG_ENDIAN_BITFIELD | |
1380 | print_num[0] = upper_num; | |
1381 | print_num[1] = lower_num; | |
1382 | #else | |
1383 | print_num[0] = lower_num; | |
1384 | print_num[1] = upper_num; | |
1385 | #endif | |
1386 | } | |
1387 | ||
f97be3ab YS |
1388 | static void btf_bitfield_seq_show(void *data, u8 bits_offset, |
1389 | u8 nr_bits, struct seq_file *m) | |
b00b8dae | 1390 | { |
b65f370d | 1391 | u16 left_shift_bits, right_shift_bits; |
36fc3c8c MKL |
1392 | u8 nr_copy_bytes; |
1393 | u8 nr_copy_bits; | |
b1e8818c | 1394 | u64 print_num[2] = {}; |
b00b8dae | 1395 | |
b00b8dae MKL |
1396 | nr_copy_bits = nr_bits + bits_offset; |
1397 | nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits); | |
1398 | ||
b1e8818c | 1399 | memcpy(print_num, data, nr_copy_bytes); |
b00b8dae | 1400 | |
b65f370d OK |
1401 | #ifdef __BIG_ENDIAN_BITFIELD |
1402 | left_shift_bits = bits_offset; | |
1403 | #else | |
b1e8818c | 1404 | left_shift_bits = BITS_PER_U128 - nr_copy_bits; |
b65f370d | 1405 | #endif |
b1e8818c | 1406 | right_shift_bits = BITS_PER_U128 - nr_bits; |
b00b8dae | 1407 | |
b1e8818c YS |
1408 | btf_int128_shift(print_num, left_shift_bits, right_shift_bits); |
1409 | btf_int128_print(m, print_num); | |
b00b8dae MKL |
1410 | } |
1411 | ||
9d5f9f70 | 1412 | |
f97be3ab YS |
1413 | static void btf_int_bits_seq_show(const struct btf *btf, |
1414 | const struct btf_type *t, | |
1415 | void *data, u8 bits_offset, | |
1416 | struct seq_file *m) | |
1417 | { | |
1418 | u32 int_data = btf_type_int(t); | |
1419 | u8 nr_bits = BTF_INT_BITS(int_data); | |
1420 | u8 total_bits_offset; | |
1421 | ||
1422 | /* | |
1423 | * bits_offset is at most 7. | |
b1e8818c | 1424 | * BTF_INT_OFFSET() cannot exceed 128 bits. |
f97be3ab YS |
1425 | */ |
1426 | total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data); | |
17e3ac81 YS |
1427 | data += BITS_ROUNDDOWN_BYTES(total_bits_offset); |
1428 | bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset); | |
1429 | btf_bitfield_seq_show(data, bits_offset, nr_bits, m); | |
f97be3ab YS |
1430 | } |
1431 | ||
b00b8dae MKL |
1432 | static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t, |
1433 | u32 type_id, void *data, u8 bits_offset, | |
1434 | struct seq_file *m) | |
1435 | { | |
1436 | u32 int_data = btf_type_int(t); | |
1437 | u8 encoding = BTF_INT_ENCODING(int_data); | |
1438 | bool sign = encoding & BTF_INT_SIGNED; | |
36fc3c8c | 1439 | u8 nr_bits = BTF_INT_BITS(int_data); |
b00b8dae MKL |
1440 | |
1441 | if (bits_offset || BTF_INT_OFFSET(int_data) || | |
1442 | BITS_PER_BYTE_MASKED(nr_bits)) { | |
1443 | btf_int_bits_seq_show(btf, t, data, bits_offset, m); | |
1444 | return; | |
1445 | } | |
1446 | ||
1447 | switch (nr_bits) { | |
b1e8818c YS |
1448 | case 128: |
1449 | btf_int128_print(m, data); | |
1450 | break; | |
b00b8dae MKL |
1451 | case 64: |
1452 | if (sign) | |
1453 | seq_printf(m, "%lld", *(s64 *)data); | |
1454 | else | |
1455 | seq_printf(m, "%llu", *(u64 *)data); | |
1456 | break; | |
1457 | case 32: | |
1458 | if (sign) | |
1459 | seq_printf(m, "%d", *(s32 *)data); | |
1460 | else | |
1461 | seq_printf(m, "%u", *(u32 *)data); | |
1462 | break; | |
1463 | case 16: | |
1464 | if (sign) | |
1465 | seq_printf(m, "%d", *(s16 *)data); | |
1466 | else | |
1467 | seq_printf(m, "%u", *(u16 *)data); | |
1468 | break; | |
1469 | case 8: | |
1470 | if (sign) | |
1471 | seq_printf(m, "%d", *(s8 *)data); | |
1472 | else | |
1473 | seq_printf(m, "%u", *(u8 *)data); | |
1474 | break; | |
1475 | default: | |
1476 | btf_int_bits_seq_show(btf, t, data, bits_offset, m); | |
1477 | } | |
1478 | } | |
1479 | ||
69b693f0 MKL |
1480 | static const struct btf_kind_operations int_ops = { |
1481 | .check_meta = btf_int_check_meta, | |
eb3f595d | 1482 | .resolve = btf_df_resolve, |
179cde8c | 1483 | .check_member = btf_int_check_member, |
9d5f9f70 | 1484 | .check_kflag_member = btf_int_check_kflag_member, |
69b693f0 | 1485 | .log_details = btf_int_log, |
b00b8dae | 1486 | .seq_show = btf_int_seq_show, |
69b693f0 MKL |
1487 | }; |
1488 | ||
179cde8c MKL |
1489 | static int btf_modifier_check_member(struct btf_verifier_env *env, |
1490 | const struct btf_type *struct_type, | |
1491 | const struct btf_member *member, | |
1492 | const struct btf_type *member_type) | |
1493 | { | |
1494 | const struct btf_type *resolved_type; | |
1495 | u32 resolved_type_id = member->type; | |
1496 | struct btf_member resolved_member; | |
1497 | struct btf *btf = env->btf; | |
1498 | ||
1499 | resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL); | |
1500 | if (!resolved_type) { | |
1501 | btf_verifier_log_member(env, struct_type, member, | |
1502 | "Invalid member"); | |
1503 | return -EINVAL; | |
1504 | } | |
1505 | ||
1506 | resolved_member = *member; | |
1507 | resolved_member.type = resolved_type_id; | |
1508 | ||
1509 | return btf_type_ops(resolved_type)->check_member(env, struct_type, | |
1510 | &resolved_member, | |
1511 | resolved_type); | |
1512 | } | |
1513 | ||
9d5f9f70 YS |
1514 | static int btf_modifier_check_kflag_member(struct btf_verifier_env *env, |
1515 | const struct btf_type *struct_type, | |
1516 | const struct btf_member *member, | |
1517 | const struct btf_type *member_type) | |
1518 | { | |
1519 | const struct btf_type *resolved_type; | |
1520 | u32 resolved_type_id = member->type; | |
1521 | struct btf_member resolved_member; | |
1522 | struct btf *btf = env->btf; | |
1523 | ||
1524 | resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL); | |
1525 | if (!resolved_type) { | |
1526 | btf_verifier_log_member(env, struct_type, member, | |
1527 | "Invalid member"); | |
1528 | return -EINVAL; | |
1529 | } | |
1530 | ||
1531 | resolved_member = *member; | |
1532 | resolved_member.type = resolved_type_id; | |
1533 | ||
1534 | return btf_type_ops(resolved_type)->check_kflag_member(env, struct_type, | |
1535 | &resolved_member, | |
1536 | resolved_type); | |
1537 | } | |
1538 | ||
179cde8c MKL |
1539 | static int btf_ptr_check_member(struct btf_verifier_env *env, |
1540 | const struct btf_type *struct_type, | |
1541 | const struct btf_member *member, | |
1542 | const struct btf_type *member_type) | |
1543 | { | |
1544 | u32 struct_size, struct_bits_off, bytes_offset; | |
1545 | ||
1546 | struct_size = struct_type->size; | |
1547 | struct_bits_off = member->offset; | |
1548 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
1549 | ||
1550 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
1551 | btf_verifier_log_member(env, struct_type, member, | |
1552 | "Member is not byte aligned"); | |
1553 | return -EINVAL; | |
1554 | } | |
1555 | ||
1556 | if (struct_size - bytes_offset < sizeof(void *)) { | |
1557 | btf_verifier_log_member(env, struct_type, member, | |
1558 | "Member exceeds struct_size"); | |
1559 | return -EINVAL; | |
1560 | } | |
1561 | ||
1562 | return 0; | |
1563 | } | |
1564 | ||
69b693f0 MKL |
1565 | static int btf_ref_type_check_meta(struct btf_verifier_env *env, |
1566 | const struct btf_type *t, | |
1567 | u32 meta_left) | |
1568 | { | |
1569 | if (btf_type_vlen(t)) { | |
1570 | btf_verifier_log_type(env, t, "vlen != 0"); | |
1571 | return -EINVAL; | |
1572 | } | |
1573 | ||
9d5f9f70 YS |
1574 | if (btf_type_kflag(t)) { |
1575 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
1576 | return -EINVAL; | |
1577 | } | |
1578 | ||
aea2f7b8 | 1579 | if (!BTF_TYPE_ID_VALID(t->type)) { |
69b693f0 MKL |
1580 | btf_verifier_log_type(env, t, "Invalid type_id"); |
1581 | return -EINVAL; | |
1582 | } | |
1583 | ||
eb04bbb6 YS |
1584 | /* typedef type must have a valid name, and other ref types, |
1585 | * volatile, const, restrict, should have a null name. | |
1586 | */ | |
1587 | if (BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF) { | |
1588 | if (!t->name_off || | |
1589 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
1590 | btf_verifier_log_type(env, t, "Invalid name"); | |
1591 | return -EINVAL; | |
1592 | } | |
1593 | } else { | |
1594 | if (t->name_off) { | |
1595 | btf_verifier_log_type(env, t, "Invalid name"); | |
1596 | return -EINVAL; | |
1597 | } | |
1598 | } | |
1599 | ||
69b693f0 MKL |
1600 | btf_verifier_log_type(env, t, NULL); |
1601 | ||
1602 | return 0; | |
1603 | } | |
1604 | ||
eb3f595d MKL |
1605 | static int btf_modifier_resolve(struct btf_verifier_env *env, |
1606 | const struct resolve_vertex *v) | |
1607 | { | |
1608 | const struct btf_type *t = v->t; | |
1609 | const struct btf_type *next_type; | |
1610 | u32 next_type_id = t->type; | |
1611 | struct btf *btf = env->btf; | |
eb3f595d MKL |
1612 | |
1613 | next_type = btf_type_by_id(btf, next_type_id); | |
1dc92851 | 1614 | if (!next_type || btf_type_is_resolve_source_only(next_type)) { |
eb3f595d MKL |
1615 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
1616 | return -EINVAL; | |
1617 | } | |
1618 | ||
eb3f595d MKL |
1619 | if (!env_type_is_resolve_sink(env, next_type) && |
1620 | !env_type_is_resolved(env, next_type_id)) | |
1621 | return env_stack_push(env, next_type, next_type_id); | |
1622 | ||
1623 | /* Figure out the resolved next_type_id with size. | |
1624 | * They will be stored in the current modifier's | |
1625 | * resolved_ids and resolved_sizes such that it can | |
1626 | * save us a few type-following when we use it later (e.g. in | |
1627 | * pretty print). | |
1628 | */ | |
1acc5d5c | 1629 | if (!btf_type_id_size(btf, &next_type_id, NULL)) { |
2667a262 MKL |
1630 | if (env_type_is_resolved(env, next_type_id)) |
1631 | next_type = btf_type_id_resolve(btf, &next_type_id); | |
1632 | ||
1633 | /* "typedef void new_void", "const void"...etc */ | |
1634 | if (!btf_type_is_void(next_type) && | |
81f5c6f5 YS |
1635 | !btf_type_is_fwd(next_type) && |
1636 | !btf_type_is_func_proto(next_type)) { | |
2667a262 MKL |
1637 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
1638 | return -EINVAL; | |
1639 | } | |
eb3f595d MKL |
1640 | } |
1641 | ||
1acc5d5c | 1642 | env_stack_pop_resolved(env, next_type_id, 0); |
eb3f595d MKL |
1643 | |
1644 | return 0; | |
1645 | } | |
1646 | ||
1dc92851 DB |
1647 | static int btf_var_resolve(struct btf_verifier_env *env, |
1648 | const struct resolve_vertex *v) | |
1649 | { | |
1650 | const struct btf_type *next_type; | |
1651 | const struct btf_type *t = v->t; | |
1652 | u32 next_type_id = t->type; | |
1653 | struct btf *btf = env->btf; | |
1dc92851 DB |
1654 | |
1655 | next_type = btf_type_by_id(btf, next_type_id); | |
1656 | if (!next_type || btf_type_is_resolve_source_only(next_type)) { | |
1657 | btf_verifier_log_type(env, v->t, "Invalid type_id"); | |
1658 | return -EINVAL; | |
1659 | } | |
1660 | ||
1661 | if (!env_type_is_resolve_sink(env, next_type) && | |
1662 | !env_type_is_resolved(env, next_type_id)) | |
1663 | return env_stack_push(env, next_type, next_type_id); | |
1664 | ||
1665 | if (btf_type_is_modifier(next_type)) { | |
1666 | const struct btf_type *resolved_type; | |
1667 | u32 resolved_type_id; | |
1668 | ||
1669 | resolved_type_id = next_type_id; | |
1670 | resolved_type = btf_type_id_resolve(btf, &resolved_type_id); | |
1671 | ||
1672 | if (btf_type_is_ptr(resolved_type) && | |
1673 | !env_type_is_resolve_sink(env, resolved_type) && | |
1674 | !env_type_is_resolved(env, resolved_type_id)) | |
1675 | return env_stack_push(env, resolved_type, | |
1676 | resolved_type_id); | |
1677 | } | |
1678 | ||
1679 | /* We must resolve to something concrete at this point, no | |
1680 | * forward types or similar that would resolve to size of | |
1681 | * zero is allowed. | |
1682 | */ | |
1acc5d5c | 1683 | if (!btf_type_id_size(btf, &next_type_id, NULL)) { |
1dc92851 DB |
1684 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
1685 | return -EINVAL; | |
1686 | } | |
1687 | ||
1acc5d5c | 1688 | env_stack_pop_resolved(env, next_type_id, 0); |
1dc92851 DB |
1689 | |
1690 | return 0; | |
1691 | } | |
1692 | ||
eb3f595d MKL |
1693 | static int btf_ptr_resolve(struct btf_verifier_env *env, |
1694 | const struct resolve_vertex *v) | |
1695 | { | |
1696 | const struct btf_type *next_type; | |
1697 | const struct btf_type *t = v->t; | |
1698 | u32 next_type_id = t->type; | |
1699 | struct btf *btf = env->btf; | |
eb3f595d MKL |
1700 | |
1701 | next_type = btf_type_by_id(btf, next_type_id); | |
1dc92851 | 1702 | if (!next_type || btf_type_is_resolve_source_only(next_type)) { |
eb3f595d MKL |
1703 | btf_verifier_log_type(env, v->t, "Invalid type_id"); |
1704 | return -EINVAL; | |
1705 | } | |
1706 | ||
eb3f595d MKL |
1707 | if (!env_type_is_resolve_sink(env, next_type) && |
1708 | !env_type_is_resolved(env, next_type_id)) | |
1709 | return env_stack_push(env, next_type, next_type_id); | |
1710 | ||
1711 | /* If the modifier was RESOLVED during RESOLVE_STRUCT_OR_ARRAY, | |
1712 | * the modifier may have stopped resolving when it was resolved | |
1713 | * to a ptr (last-resolved-ptr). | |
1714 | * | |
1715 | * We now need to continue from the last-resolved-ptr to | |
1716 | * ensure the last-resolved-ptr will not referring back to | |
1717 | * the currenct ptr (t). | |
1718 | */ | |
1719 | if (btf_type_is_modifier(next_type)) { | |
1720 | const struct btf_type *resolved_type; | |
1721 | u32 resolved_type_id; | |
1722 | ||
1723 | resolved_type_id = next_type_id; | |
1724 | resolved_type = btf_type_id_resolve(btf, &resolved_type_id); | |
1725 | ||
1726 | if (btf_type_is_ptr(resolved_type) && | |
1727 | !env_type_is_resolve_sink(env, resolved_type) && | |
1728 | !env_type_is_resolved(env, resolved_type_id)) | |
1729 | return env_stack_push(env, resolved_type, | |
1730 | resolved_type_id); | |
1731 | } | |
1732 | ||
2667a262 MKL |
1733 | if (!btf_type_id_size(btf, &next_type_id, NULL)) { |
1734 | if (env_type_is_resolved(env, next_type_id)) | |
1735 | next_type = btf_type_id_resolve(btf, &next_type_id); | |
1736 | ||
1737 | if (!btf_type_is_void(next_type) && | |
1738 | !btf_type_is_fwd(next_type) && | |
1739 | !btf_type_is_func_proto(next_type)) { | |
1740 | btf_verifier_log_type(env, v->t, "Invalid type_id"); | |
1741 | return -EINVAL; | |
1742 | } | |
eb3f595d MKL |
1743 | } |
1744 | ||
eb3f595d MKL |
1745 | env_stack_pop_resolved(env, next_type_id, 0); |
1746 | ||
1747 | return 0; | |
1748 | } | |
1749 | ||
b00b8dae MKL |
1750 | static void btf_modifier_seq_show(const struct btf *btf, |
1751 | const struct btf_type *t, | |
1752 | u32 type_id, void *data, | |
1753 | u8 bits_offset, struct seq_file *m) | |
1754 | { | |
1755 | t = btf_type_id_resolve(btf, &type_id); | |
1756 | ||
1757 | btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m); | |
1758 | } | |
1759 | ||
1dc92851 DB |
1760 | static void btf_var_seq_show(const struct btf *btf, const struct btf_type *t, |
1761 | u32 type_id, void *data, u8 bits_offset, | |
1762 | struct seq_file *m) | |
1763 | { | |
1764 | t = btf_type_id_resolve(btf, &type_id); | |
1765 | ||
1766 | btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m); | |
1767 | } | |
1768 | ||
b00b8dae MKL |
1769 | static void btf_ptr_seq_show(const struct btf *btf, const struct btf_type *t, |
1770 | u32 type_id, void *data, u8 bits_offset, | |
1771 | struct seq_file *m) | |
1772 | { | |
1773 | /* It is a hashed value */ | |
1774 | seq_printf(m, "%p", *(void **)data); | |
1775 | } | |
1776 | ||
69b693f0 MKL |
1777 | static void btf_ref_type_log(struct btf_verifier_env *env, |
1778 | const struct btf_type *t) | |
1779 | { | |
1780 | btf_verifier_log(env, "type_id=%u", t->type); | |
1781 | } | |
1782 | ||
1783 | static struct btf_kind_operations modifier_ops = { | |
1784 | .check_meta = btf_ref_type_check_meta, | |
eb3f595d | 1785 | .resolve = btf_modifier_resolve, |
179cde8c | 1786 | .check_member = btf_modifier_check_member, |
9d5f9f70 | 1787 | .check_kflag_member = btf_modifier_check_kflag_member, |
69b693f0 | 1788 | .log_details = btf_ref_type_log, |
b00b8dae | 1789 | .seq_show = btf_modifier_seq_show, |
69b693f0 MKL |
1790 | }; |
1791 | ||
1792 | static struct btf_kind_operations ptr_ops = { | |
1793 | .check_meta = btf_ref_type_check_meta, | |
eb3f595d | 1794 | .resolve = btf_ptr_resolve, |
179cde8c | 1795 | .check_member = btf_ptr_check_member, |
9d5f9f70 | 1796 | .check_kflag_member = btf_generic_check_kflag_member, |
69b693f0 | 1797 | .log_details = btf_ref_type_log, |
b00b8dae | 1798 | .seq_show = btf_ptr_seq_show, |
69b693f0 MKL |
1799 | }; |
1800 | ||
8175383f MKL |
1801 | static s32 btf_fwd_check_meta(struct btf_verifier_env *env, |
1802 | const struct btf_type *t, | |
1803 | u32 meta_left) | |
1804 | { | |
1805 | if (btf_type_vlen(t)) { | |
1806 | btf_verifier_log_type(env, t, "vlen != 0"); | |
1807 | return -EINVAL; | |
1808 | } | |
1809 | ||
1810 | if (t->type) { | |
1811 | btf_verifier_log_type(env, t, "type != 0"); | |
1812 | return -EINVAL; | |
1813 | } | |
1814 | ||
eb04bbb6 YS |
1815 | /* fwd type must have a valid name */ |
1816 | if (!t->name_off || | |
1817 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
1818 | btf_verifier_log_type(env, t, "Invalid name"); | |
1819 | return -EINVAL; | |
1820 | } | |
1821 | ||
8175383f MKL |
1822 | btf_verifier_log_type(env, t, NULL); |
1823 | ||
1824 | return 0; | |
1825 | } | |
1826 | ||
76c43ae8 YS |
1827 | static void btf_fwd_type_log(struct btf_verifier_env *env, |
1828 | const struct btf_type *t) | |
1829 | { | |
1830 | btf_verifier_log(env, "%s", btf_type_kflag(t) ? "union" : "struct"); | |
1831 | } | |
1832 | ||
69b693f0 | 1833 | static struct btf_kind_operations fwd_ops = { |
8175383f | 1834 | .check_meta = btf_fwd_check_meta, |
eb3f595d | 1835 | .resolve = btf_df_resolve, |
179cde8c | 1836 | .check_member = btf_df_check_member, |
9d5f9f70 | 1837 | .check_kflag_member = btf_df_check_kflag_member, |
76c43ae8 | 1838 | .log_details = btf_fwd_type_log, |
b00b8dae | 1839 | .seq_show = btf_df_seq_show, |
69b693f0 MKL |
1840 | }; |
1841 | ||
179cde8c MKL |
1842 | static int btf_array_check_member(struct btf_verifier_env *env, |
1843 | const struct btf_type *struct_type, | |
1844 | const struct btf_member *member, | |
1845 | const struct btf_type *member_type) | |
1846 | { | |
1847 | u32 struct_bits_off = member->offset; | |
1848 | u32 struct_size, bytes_offset; | |
1849 | u32 array_type_id, array_size; | |
1850 | struct btf *btf = env->btf; | |
1851 | ||
1852 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
1853 | btf_verifier_log_member(env, struct_type, member, | |
1854 | "Member is not byte aligned"); | |
1855 | return -EINVAL; | |
1856 | } | |
1857 | ||
1858 | array_type_id = member->type; | |
1859 | btf_type_id_size(btf, &array_type_id, &array_size); | |
1860 | struct_size = struct_type->size; | |
1861 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
1862 | if (struct_size - bytes_offset < array_size) { | |
1863 | btf_verifier_log_member(env, struct_type, member, | |
1864 | "Member exceeds struct_size"); | |
1865 | return -EINVAL; | |
1866 | } | |
1867 | ||
1868 | return 0; | |
1869 | } | |
1870 | ||
69b693f0 MKL |
1871 | static s32 btf_array_check_meta(struct btf_verifier_env *env, |
1872 | const struct btf_type *t, | |
1873 | u32 meta_left) | |
1874 | { | |
1875 | const struct btf_array *array = btf_type_array(t); | |
1876 | u32 meta_needed = sizeof(*array); | |
1877 | ||
1878 | if (meta_left < meta_needed) { | |
1879 | btf_verifier_log_basic(env, t, | |
1880 | "meta_left:%u meta_needed:%u", | |
1881 | meta_left, meta_needed); | |
1882 | return -EINVAL; | |
1883 | } | |
1884 | ||
eb04bbb6 YS |
1885 | /* array type should not have a name */ |
1886 | if (t->name_off) { | |
1887 | btf_verifier_log_type(env, t, "Invalid name"); | |
1888 | return -EINVAL; | |
1889 | } | |
1890 | ||
69b693f0 MKL |
1891 | if (btf_type_vlen(t)) { |
1892 | btf_verifier_log_type(env, t, "vlen != 0"); | |
1893 | return -EINVAL; | |
1894 | } | |
1895 | ||
9d5f9f70 YS |
1896 | if (btf_type_kflag(t)) { |
1897 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
1898 | return -EINVAL; | |
1899 | } | |
1900 | ||
b9308ae6 MKL |
1901 | if (t->size) { |
1902 | btf_verifier_log_type(env, t, "size != 0"); | |
1903 | return -EINVAL; | |
1904 | } | |
1905 | ||
4ef5f574 MKL |
1906 | /* Array elem type and index type cannot be in type void, |
1907 | * so !array->type and !array->index_type are not allowed. | |
69b693f0 | 1908 | */ |
aea2f7b8 | 1909 | if (!array->type || !BTF_TYPE_ID_VALID(array->type)) { |
4ef5f574 MKL |
1910 | btf_verifier_log_type(env, t, "Invalid elem"); |
1911 | return -EINVAL; | |
1912 | } | |
1913 | ||
aea2f7b8 | 1914 | if (!array->index_type || !BTF_TYPE_ID_VALID(array->index_type)) { |
4ef5f574 | 1915 | btf_verifier_log_type(env, t, "Invalid index"); |
69b693f0 MKL |
1916 | return -EINVAL; |
1917 | } | |
1918 | ||
1919 | btf_verifier_log_type(env, t, NULL); | |
1920 | ||
1921 | return meta_needed; | |
1922 | } | |
1923 | ||
eb3f595d MKL |
1924 | static int btf_array_resolve(struct btf_verifier_env *env, |
1925 | const struct resolve_vertex *v) | |
1926 | { | |
1927 | const struct btf_array *array = btf_type_array(v->t); | |
4ef5f574 MKL |
1928 | const struct btf_type *elem_type, *index_type; |
1929 | u32 elem_type_id, index_type_id; | |
eb3f595d MKL |
1930 | struct btf *btf = env->btf; |
1931 | u32 elem_size; | |
1932 | ||
4ef5f574 MKL |
1933 | /* Check array->index_type */ |
1934 | index_type_id = array->index_type; | |
1935 | index_type = btf_type_by_id(btf, index_type_id); | |
e4f07120 SF |
1936 | if (btf_type_nosize_or_null(index_type) || |
1937 | btf_type_is_resolve_source_only(index_type)) { | |
4ef5f574 MKL |
1938 | btf_verifier_log_type(env, v->t, "Invalid index"); |
1939 | return -EINVAL; | |
1940 | } | |
1941 | ||
1942 | if (!env_type_is_resolve_sink(env, index_type) && | |
1943 | !env_type_is_resolved(env, index_type_id)) | |
1944 | return env_stack_push(env, index_type, index_type_id); | |
1945 | ||
1946 | index_type = btf_type_id_size(btf, &index_type_id, NULL); | |
1947 | if (!index_type || !btf_type_is_int(index_type) || | |
1948 | !btf_type_int_is_regular(index_type)) { | |
1949 | btf_verifier_log_type(env, v->t, "Invalid index"); | |
1950 | return -EINVAL; | |
1951 | } | |
1952 | ||
1953 | /* Check array->type */ | |
1954 | elem_type_id = array->type; | |
eb3f595d | 1955 | elem_type = btf_type_by_id(btf, elem_type_id); |
e4f07120 SF |
1956 | if (btf_type_nosize_or_null(elem_type) || |
1957 | btf_type_is_resolve_source_only(elem_type)) { | |
eb3f595d MKL |
1958 | btf_verifier_log_type(env, v->t, |
1959 | "Invalid elem"); | |
1960 | return -EINVAL; | |
1961 | } | |
1962 | ||
1963 | if (!env_type_is_resolve_sink(env, elem_type) && | |
1964 | !env_type_is_resolved(env, elem_type_id)) | |
1965 | return env_stack_push(env, elem_type, elem_type_id); | |
1966 | ||
1967 | elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size); | |
1968 | if (!elem_type) { | |
1969 | btf_verifier_log_type(env, v->t, "Invalid elem"); | |
1970 | return -EINVAL; | |
1971 | } | |
1972 | ||
4ef5f574 MKL |
1973 | if (btf_type_is_int(elem_type) && !btf_type_int_is_regular(elem_type)) { |
1974 | btf_verifier_log_type(env, v->t, "Invalid array of int"); | |
1975 | return -EINVAL; | |
eb3f595d MKL |
1976 | } |
1977 | ||
1978 | if (array->nelems && elem_size > U32_MAX / array->nelems) { | |
1979 | btf_verifier_log_type(env, v->t, | |
1980 | "Array size overflows U32_MAX"); | |
1981 | return -EINVAL; | |
1982 | } | |
1983 | ||
1984 | env_stack_pop_resolved(env, elem_type_id, elem_size * array->nelems); | |
1985 | ||
1986 | return 0; | |
1987 | } | |
1988 | ||
69b693f0 MKL |
1989 | static void btf_array_log(struct btf_verifier_env *env, |
1990 | const struct btf_type *t) | |
1991 | { | |
1992 | const struct btf_array *array = btf_type_array(t); | |
1993 | ||
1994 | btf_verifier_log(env, "type_id=%u index_type_id=%u nr_elems=%u", | |
1995 | array->type, array->index_type, array->nelems); | |
1996 | } | |
1997 | ||
b00b8dae MKL |
1998 | static void btf_array_seq_show(const struct btf *btf, const struct btf_type *t, |
1999 | u32 type_id, void *data, u8 bits_offset, | |
2000 | struct seq_file *m) | |
2001 | { | |
2002 | const struct btf_array *array = btf_type_array(t); | |
2003 | const struct btf_kind_operations *elem_ops; | |
2004 | const struct btf_type *elem_type; | |
2005 | u32 i, elem_size, elem_type_id; | |
2006 | ||
2007 | elem_type_id = array->type; | |
2008 | elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size); | |
2009 | elem_ops = btf_type_ops(elem_type); | |
2010 | seq_puts(m, "["); | |
2011 | for (i = 0; i < array->nelems; i++) { | |
2012 | if (i) | |
2013 | seq_puts(m, ","); | |
2014 | ||
2015 | elem_ops->seq_show(btf, elem_type, elem_type_id, data, | |
2016 | bits_offset, m); | |
2017 | data += elem_size; | |
2018 | } | |
2019 | seq_puts(m, "]"); | |
2020 | } | |
2021 | ||
69b693f0 MKL |
2022 | static struct btf_kind_operations array_ops = { |
2023 | .check_meta = btf_array_check_meta, | |
eb3f595d | 2024 | .resolve = btf_array_resolve, |
179cde8c | 2025 | .check_member = btf_array_check_member, |
9d5f9f70 | 2026 | .check_kflag_member = btf_generic_check_kflag_member, |
69b693f0 | 2027 | .log_details = btf_array_log, |
b00b8dae | 2028 | .seq_show = btf_array_seq_show, |
69b693f0 MKL |
2029 | }; |
2030 | ||
179cde8c MKL |
2031 | static int btf_struct_check_member(struct btf_verifier_env *env, |
2032 | const struct btf_type *struct_type, | |
2033 | const struct btf_member *member, | |
2034 | const struct btf_type *member_type) | |
2035 | { | |
2036 | u32 struct_bits_off = member->offset; | |
2037 | u32 struct_size, bytes_offset; | |
2038 | ||
2039 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
2040 | btf_verifier_log_member(env, struct_type, member, | |
2041 | "Member is not byte aligned"); | |
2042 | return -EINVAL; | |
2043 | } | |
2044 | ||
2045 | struct_size = struct_type->size; | |
2046 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
2047 | if (struct_size - bytes_offset < member_type->size) { | |
2048 | btf_verifier_log_member(env, struct_type, member, | |
2049 | "Member exceeds struct_size"); | |
2050 | return -EINVAL; | |
2051 | } | |
2052 | ||
2053 | return 0; | |
2054 | } | |
2055 | ||
69b693f0 MKL |
2056 | static s32 btf_struct_check_meta(struct btf_verifier_env *env, |
2057 | const struct btf_type *t, | |
2058 | u32 meta_left) | |
2059 | { | |
2060 | bool is_union = BTF_INFO_KIND(t->info) == BTF_KIND_UNION; | |
2061 | const struct btf_member *member; | |
6283fa38 | 2062 | u32 meta_needed, last_offset; |
69b693f0 MKL |
2063 | struct btf *btf = env->btf; |
2064 | u32 struct_size = t->size; | |
9d5f9f70 | 2065 | u32 offset; |
69b693f0 MKL |
2066 | u16 i; |
2067 | ||
2068 | meta_needed = btf_type_vlen(t) * sizeof(*member); | |
2069 | if (meta_left < meta_needed) { | |
2070 | btf_verifier_log_basic(env, t, | |
2071 | "meta_left:%u meta_needed:%u", | |
2072 | meta_left, meta_needed); | |
2073 | return -EINVAL; | |
2074 | } | |
2075 | ||
eb04bbb6 YS |
2076 | /* struct type either no name or a valid one */ |
2077 | if (t->name_off && | |
2078 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
2079 | btf_verifier_log_type(env, t, "Invalid name"); | |
2080 | return -EINVAL; | |
2081 | } | |
2082 | ||
69b693f0 MKL |
2083 | btf_verifier_log_type(env, t, NULL); |
2084 | ||
6283fa38 | 2085 | last_offset = 0; |
69b693f0 | 2086 | for_each_member(i, t, member) { |
fbcf93eb | 2087 | if (!btf_name_offset_valid(btf, member->name_off)) { |
69b693f0 MKL |
2088 | btf_verifier_log_member(env, t, member, |
2089 | "Invalid member name_offset:%u", | |
fbcf93eb | 2090 | member->name_off); |
69b693f0 MKL |
2091 | return -EINVAL; |
2092 | } | |
2093 | ||
eb04bbb6 YS |
2094 | /* struct member either no name or a valid one */ |
2095 | if (member->name_off && | |
2096 | !btf_name_valid_identifier(btf, member->name_off)) { | |
2097 | btf_verifier_log_member(env, t, member, "Invalid name"); | |
2098 | return -EINVAL; | |
2099 | } | |
69b693f0 | 2100 | /* A member cannot be in type void */ |
aea2f7b8 | 2101 | if (!member->type || !BTF_TYPE_ID_VALID(member->type)) { |
69b693f0 MKL |
2102 | btf_verifier_log_member(env, t, member, |
2103 | "Invalid type_id"); | |
2104 | return -EINVAL; | |
2105 | } | |
2106 | ||
9d5f9f70 YS |
2107 | offset = btf_member_bit_offset(t, member); |
2108 | if (is_union && offset) { | |
69b693f0 MKL |
2109 | btf_verifier_log_member(env, t, member, |
2110 | "Invalid member bits_offset"); | |
2111 | return -EINVAL; | |
2112 | } | |
2113 | ||
6283fa38 MKL |
2114 | /* |
2115 | * ">" instead of ">=" because the last member could be | |
2116 | * "char a[0];" | |
2117 | */ | |
9d5f9f70 | 2118 | if (last_offset > offset) { |
6283fa38 MKL |
2119 | btf_verifier_log_member(env, t, member, |
2120 | "Invalid member bits_offset"); | |
2121 | return -EINVAL; | |
2122 | } | |
2123 | ||
9d5f9f70 | 2124 | if (BITS_ROUNDUP_BYTES(offset) > struct_size) { |
69b693f0 | 2125 | btf_verifier_log_member(env, t, member, |
311fe1a8 | 2126 | "Member bits_offset exceeds its struct size"); |
69b693f0 MKL |
2127 | return -EINVAL; |
2128 | } | |
2129 | ||
2130 | btf_verifier_log_member(env, t, member, NULL); | |
9d5f9f70 | 2131 | last_offset = offset; |
69b693f0 MKL |
2132 | } |
2133 | ||
2134 | return meta_needed; | |
2135 | } | |
2136 | ||
eb3f595d MKL |
2137 | static int btf_struct_resolve(struct btf_verifier_env *env, |
2138 | const struct resolve_vertex *v) | |
2139 | { | |
2140 | const struct btf_member *member; | |
179cde8c | 2141 | int err; |
eb3f595d MKL |
2142 | u16 i; |
2143 | ||
2144 | /* Before continue resolving the next_member, | |
2145 | * ensure the last member is indeed resolved to a | |
2146 | * type with size info. | |
2147 | */ | |
2148 | if (v->next_member) { | |
179cde8c | 2149 | const struct btf_type *last_member_type; |
eb3f595d MKL |
2150 | const struct btf_member *last_member; |
2151 | u16 last_member_type_id; | |
2152 | ||
2153 | last_member = btf_type_member(v->t) + v->next_member - 1; | |
2154 | last_member_type_id = last_member->type; | |
2155 | if (WARN_ON_ONCE(!env_type_is_resolved(env, | |
2156 | last_member_type_id))) | |
2157 | return -EINVAL; | |
179cde8c MKL |
2158 | |
2159 | last_member_type = btf_type_by_id(env->btf, | |
2160 | last_member_type_id); | |
9d5f9f70 YS |
2161 | if (btf_type_kflag(v->t)) |
2162 | err = btf_type_ops(last_member_type)->check_kflag_member(env, v->t, | |
2163 | last_member, | |
2164 | last_member_type); | |
2165 | else | |
2166 | err = btf_type_ops(last_member_type)->check_member(env, v->t, | |
2167 | last_member, | |
2168 | last_member_type); | |
179cde8c MKL |
2169 | if (err) |
2170 | return err; | |
eb3f595d MKL |
2171 | } |
2172 | ||
2173 | for_each_member_from(i, v->next_member, v->t, member) { | |
2174 | u32 member_type_id = member->type; | |
2175 | const struct btf_type *member_type = btf_type_by_id(env->btf, | |
2176 | member_type_id); | |
2177 | ||
e4f07120 SF |
2178 | if (btf_type_nosize_or_null(member_type) || |
2179 | btf_type_is_resolve_source_only(member_type)) { | |
eb3f595d MKL |
2180 | btf_verifier_log_member(env, v->t, member, |
2181 | "Invalid member"); | |
2182 | return -EINVAL; | |
2183 | } | |
2184 | ||
2185 | if (!env_type_is_resolve_sink(env, member_type) && | |
2186 | !env_type_is_resolved(env, member_type_id)) { | |
2187 | env_stack_set_next_member(env, i + 1); | |
2188 | return env_stack_push(env, member_type, member_type_id); | |
2189 | } | |
179cde8c | 2190 | |
9d5f9f70 YS |
2191 | if (btf_type_kflag(v->t)) |
2192 | err = btf_type_ops(member_type)->check_kflag_member(env, v->t, | |
2193 | member, | |
2194 | member_type); | |
2195 | else | |
2196 | err = btf_type_ops(member_type)->check_member(env, v->t, | |
2197 | member, | |
2198 | member_type); | |
179cde8c MKL |
2199 | if (err) |
2200 | return err; | |
eb3f595d MKL |
2201 | } |
2202 | ||
2203 | env_stack_pop_resolved(env, 0, 0); | |
2204 | ||
2205 | return 0; | |
2206 | } | |
2207 | ||
69b693f0 MKL |
2208 | static void btf_struct_log(struct btf_verifier_env *env, |
2209 | const struct btf_type *t) | |
2210 | { | |
2211 | btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); | |
2212 | } | |
2213 | ||
d83525ca AS |
2214 | /* find 'struct bpf_spin_lock' in map value. |
2215 | * return >= 0 offset if found | |
2216 | * and < 0 in case of error | |
2217 | */ | |
2218 | int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t) | |
2219 | { | |
2220 | const struct btf_member *member; | |
2221 | u32 i, off = -ENOENT; | |
2222 | ||
2223 | if (!__btf_type_is_struct(t)) | |
2224 | return -EINVAL; | |
2225 | ||
2226 | for_each_member(i, t, member) { | |
2227 | const struct btf_type *member_type = btf_type_by_id(btf, | |
2228 | member->type); | |
2229 | if (!__btf_type_is_struct(member_type)) | |
2230 | continue; | |
2231 | if (member_type->size != sizeof(struct bpf_spin_lock)) | |
2232 | continue; | |
2233 | if (strcmp(__btf_name_by_offset(btf, member_type->name_off), | |
2234 | "bpf_spin_lock")) | |
2235 | continue; | |
2236 | if (off != -ENOENT) | |
2237 | /* only one 'struct bpf_spin_lock' is allowed */ | |
2238 | return -E2BIG; | |
2239 | off = btf_member_bit_offset(t, member); | |
2240 | if (off % 8) | |
2241 | /* valid C code cannot generate such BTF */ | |
2242 | return -EINVAL; | |
2243 | off /= 8; | |
2244 | if (off % __alignof__(struct bpf_spin_lock)) | |
2245 | /* valid struct bpf_spin_lock will be 4 byte aligned */ | |
2246 | return -EINVAL; | |
2247 | } | |
2248 | return off; | |
2249 | } | |
2250 | ||
b00b8dae MKL |
2251 | static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t, |
2252 | u32 type_id, void *data, u8 bits_offset, | |
2253 | struct seq_file *m) | |
2254 | { | |
2255 | const char *seq = BTF_INFO_KIND(t->info) == BTF_KIND_UNION ? "|" : ","; | |
2256 | const struct btf_member *member; | |
2257 | u32 i; | |
2258 | ||
2259 | seq_puts(m, "{"); | |
2260 | for_each_member(i, t, member) { | |
2261 | const struct btf_type *member_type = btf_type_by_id(btf, | |
2262 | member->type); | |
b00b8dae | 2263 | const struct btf_kind_operations *ops; |
9d5f9f70 YS |
2264 | u32 member_offset, bitfield_size; |
2265 | u32 bytes_offset; | |
2266 | u8 bits8_offset; | |
b00b8dae MKL |
2267 | |
2268 | if (i) | |
2269 | seq_puts(m, seq); | |
2270 | ||
9d5f9f70 YS |
2271 | member_offset = btf_member_bit_offset(t, member); |
2272 | bitfield_size = btf_member_bitfield_size(t, member); | |
17e3ac81 YS |
2273 | bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); |
2274 | bits8_offset = BITS_PER_BYTE_MASKED(member_offset); | |
9d5f9f70 | 2275 | if (bitfield_size) { |
17e3ac81 | 2276 | btf_bitfield_seq_show(data + bytes_offset, bits8_offset, |
9d5f9f70 YS |
2277 | bitfield_size, m); |
2278 | } else { | |
9d5f9f70 YS |
2279 | ops = btf_type_ops(member_type); |
2280 | ops->seq_show(btf, member_type, member->type, | |
2281 | data + bytes_offset, bits8_offset, m); | |
2282 | } | |
b00b8dae MKL |
2283 | } |
2284 | seq_puts(m, "}"); | |
2285 | } | |
2286 | ||
69b693f0 MKL |
2287 | static struct btf_kind_operations struct_ops = { |
2288 | .check_meta = btf_struct_check_meta, | |
eb3f595d | 2289 | .resolve = btf_struct_resolve, |
179cde8c | 2290 | .check_member = btf_struct_check_member, |
9d5f9f70 | 2291 | .check_kflag_member = btf_generic_check_kflag_member, |
69b693f0 | 2292 | .log_details = btf_struct_log, |
b00b8dae | 2293 | .seq_show = btf_struct_seq_show, |
69b693f0 MKL |
2294 | }; |
2295 | ||
179cde8c MKL |
2296 | static int btf_enum_check_member(struct btf_verifier_env *env, |
2297 | const struct btf_type *struct_type, | |
2298 | const struct btf_member *member, | |
2299 | const struct btf_type *member_type) | |
2300 | { | |
2301 | u32 struct_bits_off = member->offset; | |
2302 | u32 struct_size, bytes_offset; | |
2303 | ||
2304 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
2305 | btf_verifier_log_member(env, struct_type, member, | |
2306 | "Member is not byte aligned"); | |
2307 | return -EINVAL; | |
2308 | } | |
2309 | ||
2310 | struct_size = struct_type->size; | |
2311 | bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); | |
2312 | if (struct_size - bytes_offset < sizeof(int)) { | |
2313 | btf_verifier_log_member(env, struct_type, member, | |
2314 | "Member exceeds struct_size"); | |
2315 | return -EINVAL; | |
2316 | } | |
2317 | ||
2318 | return 0; | |
2319 | } | |
2320 | ||
9d5f9f70 YS |
2321 | static int btf_enum_check_kflag_member(struct btf_verifier_env *env, |
2322 | const struct btf_type *struct_type, | |
2323 | const struct btf_member *member, | |
2324 | const struct btf_type *member_type) | |
2325 | { | |
2326 | u32 struct_bits_off, nr_bits, bytes_end, struct_size; | |
2327 | u32 int_bitsize = sizeof(int) * BITS_PER_BYTE; | |
2328 | ||
2329 | struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset); | |
2330 | nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset); | |
2331 | if (!nr_bits) { | |
2332 | if (BITS_PER_BYTE_MASKED(struct_bits_off)) { | |
2333 | btf_verifier_log_member(env, struct_type, member, | |
2334 | "Member is not byte aligned"); | |
e3439af4 | 2335 | return -EINVAL; |
9d5f9f70 YS |
2336 | } |
2337 | ||
2338 | nr_bits = int_bitsize; | |
2339 | } else if (nr_bits > int_bitsize) { | |
2340 | btf_verifier_log_member(env, struct_type, member, | |
2341 | "Invalid member bitfield_size"); | |
2342 | return -EINVAL; | |
2343 | } | |
2344 | ||
2345 | struct_size = struct_type->size; | |
2346 | bytes_end = BITS_ROUNDUP_BYTES(struct_bits_off + nr_bits); | |
2347 | if (struct_size < bytes_end) { | |
2348 | btf_verifier_log_member(env, struct_type, member, | |
2349 | "Member exceeds struct_size"); | |
2350 | return -EINVAL; | |
2351 | } | |
2352 | ||
2353 | return 0; | |
2354 | } | |
2355 | ||
69b693f0 MKL |
2356 | static s32 btf_enum_check_meta(struct btf_verifier_env *env, |
2357 | const struct btf_type *t, | |
2358 | u32 meta_left) | |
2359 | { | |
2360 | const struct btf_enum *enums = btf_type_enum(t); | |
2361 | struct btf *btf = env->btf; | |
2362 | u16 i, nr_enums; | |
2363 | u32 meta_needed; | |
2364 | ||
2365 | nr_enums = btf_type_vlen(t); | |
2366 | meta_needed = nr_enums * sizeof(*enums); | |
2367 | ||
2368 | if (meta_left < meta_needed) { | |
2369 | btf_verifier_log_basic(env, t, | |
2370 | "meta_left:%u meta_needed:%u", | |
2371 | meta_left, meta_needed); | |
2372 | return -EINVAL; | |
2373 | } | |
2374 | ||
9d5f9f70 YS |
2375 | if (btf_type_kflag(t)) { |
2376 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2377 | return -EINVAL; | |
2378 | } | |
2379 | ||
9eea9849 AS |
2380 | if (t->size > 8 || !is_power_of_2(t->size)) { |
2381 | btf_verifier_log_type(env, t, "Unexpected size"); | |
69b693f0 MKL |
2382 | return -EINVAL; |
2383 | } | |
2384 | ||
eb04bbb6 YS |
2385 | /* enum type either no name or a valid one */ |
2386 | if (t->name_off && | |
2387 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
2388 | btf_verifier_log_type(env, t, "Invalid name"); | |
2389 | return -EINVAL; | |
2390 | } | |
2391 | ||
69b693f0 MKL |
2392 | btf_verifier_log_type(env, t, NULL); |
2393 | ||
2394 | for (i = 0; i < nr_enums; i++) { | |
fbcf93eb | 2395 | if (!btf_name_offset_valid(btf, enums[i].name_off)) { |
69b693f0 | 2396 | btf_verifier_log(env, "\tInvalid name_offset:%u", |
fbcf93eb | 2397 | enums[i].name_off); |
69b693f0 MKL |
2398 | return -EINVAL; |
2399 | } | |
2400 | ||
eb04bbb6 YS |
2401 | /* enum member must have a valid name */ |
2402 | if (!enums[i].name_off || | |
2403 | !btf_name_valid_identifier(btf, enums[i].name_off)) { | |
2404 | btf_verifier_log_type(env, t, "Invalid name"); | |
2405 | return -EINVAL; | |
2406 | } | |
2407 | ||
2408 | ||
69b693f0 | 2409 | btf_verifier_log(env, "\t%s val=%d\n", |
23127b33 | 2410 | __btf_name_by_offset(btf, enums[i].name_off), |
69b693f0 MKL |
2411 | enums[i].val); |
2412 | } | |
2413 | ||
2414 | return meta_needed; | |
2415 | } | |
2416 | ||
2417 | static void btf_enum_log(struct btf_verifier_env *env, | |
2418 | const struct btf_type *t) | |
2419 | { | |
2420 | btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); | |
2421 | } | |
2422 | ||
b00b8dae MKL |
2423 | static void btf_enum_seq_show(const struct btf *btf, const struct btf_type *t, |
2424 | u32 type_id, void *data, u8 bits_offset, | |
2425 | struct seq_file *m) | |
2426 | { | |
2427 | const struct btf_enum *enums = btf_type_enum(t); | |
2428 | u32 i, nr_enums = btf_type_vlen(t); | |
2429 | int v = *(int *)data; | |
2430 | ||
2431 | for (i = 0; i < nr_enums; i++) { | |
2432 | if (v == enums[i].val) { | |
2433 | seq_printf(m, "%s", | |
23127b33 MKL |
2434 | __btf_name_by_offset(btf, |
2435 | enums[i].name_off)); | |
b00b8dae MKL |
2436 | return; |
2437 | } | |
2438 | } | |
2439 | ||
2440 | seq_printf(m, "%d", v); | |
2441 | } | |
2442 | ||
69b693f0 MKL |
2443 | static struct btf_kind_operations enum_ops = { |
2444 | .check_meta = btf_enum_check_meta, | |
eb3f595d | 2445 | .resolve = btf_df_resolve, |
179cde8c | 2446 | .check_member = btf_enum_check_member, |
9d5f9f70 | 2447 | .check_kflag_member = btf_enum_check_kflag_member, |
69b693f0 | 2448 | .log_details = btf_enum_log, |
b00b8dae | 2449 | .seq_show = btf_enum_seq_show, |
69b693f0 MKL |
2450 | }; |
2451 | ||
2667a262 MKL |
2452 | static s32 btf_func_proto_check_meta(struct btf_verifier_env *env, |
2453 | const struct btf_type *t, | |
2454 | u32 meta_left) | |
2455 | { | |
2456 | u32 meta_needed = btf_type_vlen(t) * sizeof(struct btf_param); | |
2457 | ||
2458 | if (meta_left < meta_needed) { | |
2459 | btf_verifier_log_basic(env, t, | |
2460 | "meta_left:%u meta_needed:%u", | |
2461 | meta_left, meta_needed); | |
2462 | return -EINVAL; | |
2463 | } | |
2464 | ||
2465 | if (t->name_off) { | |
2466 | btf_verifier_log_type(env, t, "Invalid name"); | |
2467 | return -EINVAL; | |
2468 | } | |
2469 | ||
9d5f9f70 YS |
2470 | if (btf_type_kflag(t)) { |
2471 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2472 | return -EINVAL; | |
2473 | } | |
2474 | ||
2667a262 MKL |
2475 | btf_verifier_log_type(env, t, NULL); |
2476 | ||
2477 | return meta_needed; | |
2478 | } | |
2479 | ||
2480 | static void btf_func_proto_log(struct btf_verifier_env *env, | |
2481 | const struct btf_type *t) | |
2482 | { | |
2483 | const struct btf_param *args = (const struct btf_param *)(t + 1); | |
2484 | u16 nr_args = btf_type_vlen(t), i; | |
2485 | ||
2486 | btf_verifier_log(env, "return=%u args=(", t->type); | |
2487 | if (!nr_args) { | |
2488 | btf_verifier_log(env, "void"); | |
2489 | goto done; | |
2490 | } | |
2491 | ||
2492 | if (nr_args == 1 && !args[0].type) { | |
2493 | /* Only one vararg */ | |
2494 | btf_verifier_log(env, "vararg"); | |
2495 | goto done; | |
2496 | } | |
2497 | ||
2498 | btf_verifier_log(env, "%u %s", args[0].type, | |
23127b33 MKL |
2499 | __btf_name_by_offset(env->btf, |
2500 | args[0].name_off)); | |
2667a262 MKL |
2501 | for (i = 1; i < nr_args - 1; i++) |
2502 | btf_verifier_log(env, ", %u %s", args[i].type, | |
23127b33 MKL |
2503 | __btf_name_by_offset(env->btf, |
2504 | args[i].name_off)); | |
2667a262 MKL |
2505 | |
2506 | if (nr_args > 1) { | |
2507 | const struct btf_param *last_arg = &args[nr_args - 1]; | |
2508 | ||
2509 | if (last_arg->type) | |
2510 | btf_verifier_log(env, ", %u %s", last_arg->type, | |
23127b33 MKL |
2511 | __btf_name_by_offset(env->btf, |
2512 | last_arg->name_off)); | |
2667a262 MKL |
2513 | else |
2514 | btf_verifier_log(env, ", vararg"); | |
2515 | } | |
2516 | ||
2517 | done: | |
2518 | btf_verifier_log(env, ")"); | |
2519 | } | |
2520 | ||
2521 | static struct btf_kind_operations func_proto_ops = { | |
2522 | .check_meta = btf_func_proto_check_meta, | |
2523 | .resolve = btf_df_resolve, | |
2524 | /* | |
2525 | * BTF_KIND_FUNC_PROTO cannot be directly referred by | |
2526 | * a struct's member. | |
2527 | * | |
2528 | * It should be a funciton pointer instead. | |
2529 | * (i.e. struct's member -> BTF_KIND_PTR -> BTF_KIND_FUNC_PROTO) | |
2530 | * | |
2531 | * Hence, there is no btf_func_check_member(). | |
2532 | */ | |
2533 | .check_member = btf_df_check_member, | |
9d5f9f70 | 2534 | .check_kflag_member = btf_df_check_kflag_member, |
2667a262 MKL |
2535 | .log_details = btf_func_proto_log, |
2536 | .seq_show = btf_df_seq_show, | |
2537 | }; | |
2538 | ||
2539 | static s32 btf_func_check_meta(struct btf_verifier_env *env, | |
2540 | const struct btf_type *t, | |
2541 | u32 meta_left) | |
2542 | { | |
2543 | if (!t->name_off || | |
2544 | !btf_name_valid_identifier(env->btf, t->name_off)) { | |
2545 | btf_verifier_log_type(env, t, "Invalid name"); | |
2546 | return -EINVAL; | |
2547 | } | |
2548 | ||
2549 | if (btf_type_vlen(t)) { | |
2550 | btf_verifier_log_type(env, t, "vlen != 0"); | |
2551 | return -EINVAL; | |
2552 | } | |
2553 | ||
9d5f9f70 YS |
2554 | if (btf_type_kflag(t)) { |
2555 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2556 | return -EINVAL; | |
2557 | } | |
2558 | ||
2667a262 MKL |
2559 | btf_verifier_log_type(env, t, NULL); |
2560 | ||
2561 | return 0; | |
2562 | } | |
2563 | ||
2564 | static struct btf_kind_operations func_ops = { | |
2565 | .check_meta = btf_func_check_meta, | |
2566 | .resolve = btf_df_resolve, | |
2567 | .check_member = btf_df_check_member, | |
9d5f9f70 | 2568 | .check_kflag_member = btf_df_check_kflag_member, |
2667a262 MKL |
2569 | .log_details = btf_ref_type_log, |
2570 | .seq_show = btf_df_seq_show, | |
2571 | }; | |
2572 | ||
1dc92851 DB |
2573 | static s32 btf_var_check_meta(struct btf_verifier_env *env, |
2574 | const struct btf_type *t, | |
2575 | u32 meta_left) | |
2576 | { | |
2577 | const struct btf_var *var; | |
2578 | u32 meta_needed = sizeof(*var); | |
2579 | ||
2580 | if (meta_left < meta_needed) { | |
2581 | btf_verifier_log_basic(env, t, | |
2582 | "meta_left:%u meta_needed:%u", | |
2583 | meta_left, meta_needed); | |
2584 | return -EINVAL; | |
2585 | } | |
2586 | ||
2587 | if (btf_type_vlen(t)) { | |
2588 | btf_verifier_log_type(env, t, "vlen != 0"); | |
2589 | return -EINVAL; | |
2590 | } | |
2591 | ||
2592 | if (btf_type_kflag(t)) { | |
2593 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2594 | return -EINVAL; | |
2595 | } | |
2596 | ||
2597 | if (!t->name_off || | |
2598 | !__btf_name_valid(env->btf, t->name_off, true)) { | |
2599 | btf_verifier_log_type(env, t, "Invalid name"); | |
2600 | return -EINVAL; | |
2601 | } | |
2602 | ||
2603 | /* A var cannot be in type void */ | |
2604 | if (!t->type || !BTF_TYPE_ID_VALID(t->type)) { | |
2605 | btf_verifier_log_type(env, t, "Invalid type_id"); | |
2606 | return -EINVAL; | |
2607 | } | |
2608 | ||
2609 | var = btf_type_var(t); | |
2610 | if (var->linkage != BTF_VAR_STATIC && | |
2611 | var->linkage != BTF_VAR_GLOBAL_ALLOCATED) { | |
2612 | btf_verifier_log_type(env, t, "Linkage not supported"); | |
2613 | return -EINVAL; | |
2614 | } | |
2615 | ||
2616 | btf_verifier_log_type(env, t, NULL); | |
2617 | ||
2618 | return meta_needed; | |
2619 | } | |
2620 | ||
2621 | static void btf_var_log(struct btf_verifier_env *env, const struct btf_type *t) | |
2622 | { | |
2623 | const struct btf_var *var = btf_type_var(t); | |
2624 | ||
2625 | btf_verifier_log(env, "type_id=%u linkage=%u", t->type, var->linkage); | |
2626 | } | |
2627 | ||
2628 | static const struct btf_kind_operations var_ops = { | |
2629 | .check_meta = btf_var_check_meta, | |
2630 | .resolve = btf_var_resolve, | |
2631 | .check_member = btf_df_check_member, | |
2632 | .check_kflag_member = btf_df_check_kflag_member, | |
2633 | .log_details = btf_var_log, | |
2634 | .seq_show = btf_var_seq_show, | |
2635 | }; | |
2636 | ||
2637 | static s32 btf_datasec_check_meta(struct btf_verifier_env *env, | |
2638 | const struct btf_type *t, | |
2639 | u32 meta_left) | |
2640 | { | |
2641 | const struct btf_var_secinfo *vsi; | |
2642 | u64 last_vsi_end_off = 0, sum = 0; | |
2643 | u32 i, meta_needed; | |
2644 | ||
2645 | meta_needed = btf_type_vlen(t) * sizeof(*vsi); | |
2646 | if (meta_left < meta_needed) { | |
2647 | btf_verifier_log_basic(env, t, | |
2648 | "meta_left:%u meta_needed:%u", | |
2649 | meta_left, meta_needed); | |
2650 | return -EINVAL; | |
2651 | } | |
2652 | ||
2653 | if (!btf_type_vlen(t)) { | |
2654 | btf_verifier_log_type(env, t, "vlen == 0"); | |
2655 | return -EINVAL; | |
2656 | } | |
2657 | ||
2658 | if (!t->size) { | |
2659 | btf_verifier_log_type(env, t, "size == 0"); | |
2660 | return -EINVAL; | |
2661 | } | |
2662 | ||
2663 | if (btf_type_kflag(t)) { | |
2664 | btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); | |
2665 | return -EINVAL; | |
2666 | } | |
2667 | ||
2668 | if (!t->name_off || | |
2669 | !btf_name_valid_section(env->btf, t->name_off)) { | |
2670 | btf_verifier_log_type(env, t, "Invalid name"); | |
2671 | return -EINVAL; | |
2672 | } | |
2673 | ||
2674 | btf_verifier_log_type(env, t, NULL); | |
2675 | ||
2676 | for_each_vsi(i, t, vsi) { | |
2677 | /* A var cannot be in type void */ | |
2678 | if (!vsi->type || !BTF_TYPE_ID_VALID(vsi->type)) { | |
2679 | btf_verifier_log_vsi(env, t, vsi, | |
2680 | "Invalid type_id"); | |
2681 | return -EINVAL; | |
2682 | } | |
2683 | ||
2684 | if (vsi->offset < last_vsi_end_off || vsi->offset >= t->size) { | |
2685 | btf_verifier_log_vsi(env, t, vsi, | |
2686 | "Invalid offset"); | |
2687 | return -EINVAL; | |
2688 | } | |
2689 | ||
2690 | if (!vsi->size || vsi->size > t->size) { | |
2691 | btf_verifier_log_vsi(env, t, vsi, | |
2692 | "Invalid size"); | |
2693 | return -EINVAL; | |
2694 | } | |
2695 | ||
2696 | last_vsi_end_off = vsi->offset + vsi->size; | |
2697 | if (last_vsi_end_off > t->size) { | |
2698 | btf_verifier_log_vsi(env, t, vsi, | |
2699 | "Invalid offset+size"); | |
2700 | return -EINVAL; | |
2701 | } | |
2702 | ||
2703 | btf_verifier_log_vsi(env, t, vsi, NULL); | |
2704 | sum += vsi->size; | |
2705 | } | |
2706 | ||
2707 | if (t->size < sum) { | |
2708 | btf_verifier_log_type(env, t, "Invalid btf_info size"); | |
2709 | return -EINVAL; | |
2710 | } | |
2711 | ||
2712 | return meta_needed; | |
2713 | } | |
2714 | ||
2715 | static int btf_datasec_resolve(struct btf_verifier_env *env, | |
2716 | const struct resolve_vertex *v) | |
2717 | { | |
2718 | const struct btf_var_secinfo *vsi; | |
2719 | struct btf *btf = env->btf; | |
2720 | u16 i; | |
2721 | ||
2722 | for_each_vsi_from(i, v->next_member, v->t, vsi) { | |
2723 | u32 var_type_id = vsi->type, type_id, type_size = 0; | |
2724 | const struct btf_type *var_type = btf_type_by_id(env->btf, | |
2725 | var_type_id); | |
2726 | if (!var_type || !btf_type_is_var(var_type)) { | |
2727 | btf_verifier_log_vsi(env, v->t, vsi, | |
2728 | "Not a VAR kind member"); | |
2729 | return -EINVAL; | |
2730 | } | |
2731 | ||
2732 | if (!env_type_is_resolve_sink(env, var_type) && | |
2733 | !env_type_is_resolved(env, var_type_id)) { | |
2734 | env_stack_set_next_member(env, i + 1); | |
2735 | return env_stack_push(env, var_type, var_type_id); | |
2736 | } | |
2737 | ||
2738 | type_id = var_type->type; | |
2739 | if (!btf_type_id_size(btf, &type_id, &type_size)) { | |
2740 | btf_verifier_log_vsi(env, v->t, vsi, "Invalid type"); | |
2741 | return -EINVAL; | |
2742 | } | |
2743 | ||
2744 | if (vsi->size < type_size) { | |
2745 | btf_verifier_log_vsi(env, v->t, vsi, "Invalid size"); | |
2746 | return -EINVAL; | |
2747 | } | |
2748 | } | |
2749 | ||
2750 | env_stack_pop_resolved(env, 0, 0); | |
2751 | return 0; | |
2752 | } | |
2753 | ||
2754 | static void btf_datasec_log(struct btf_verifier_env *env, | |
2755 | const struct btf_type *t) | |
2756 | { | |
2757 | btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); | |
2758 | } | |
2759 | ||
2760 | static void btf_datasec_seq_show(const struct btf *btf, | |
2761 | const struct btf_type *t, u32 type_id, | |
2762 | void *data, u8 bits_offset, | |
2763 | struct seq_file *m) | |
2764 | { | |
2765 | const struct btf_var_secinfo *vsi; | |
2766 | const struct btf_type *var; | |
2767 | u32 i; | |
2768 | ||
2769 | seq_printf(m, "section (\"%s\") = {", __btf_name_by_offset(btf, t->name_off)); | |
2770 | for_each_vsi(i, t, vsi) { | |
2771 | var = btf_type_by_id(btf, vsi->type); | |
2772 | if (i) | |
2773 | seq_puts(m, ","); | |
2774 | btf_type_ops(var)->seq_show(btf, var, vsi->type, | |
2775 | data + vsi->offset, bits_offset, m); | |
2776 | } | |
2777 | seq_puts(m, "}"); | |
2778 | } | |
2779 | ||
2780 | static const struct btf_kind_operations datasec_ops = { | |
2781 | .check_meta = btf_datasec_check_meta, | |
2782 | .resolve = btf_datasec_resolve, | |
2783 | .check_member = btf_df_check_member, | |
2784 | .check_kflag_member = btf_df_check_kflag_member, | |
2785 | .log_details = btf_datasec_log, | |
2786 | .seq_show = btf_datasec_seq_show, | |
2787 | }; | |
2788 | ||
2667a262 MKL |
2789 | static int btf_func_proto_check(struct btf_verifier_env *env, |
2790 | const struct btf_type *t) | |
2791 | { | |
2792 | const struct btf_type *ret_type; | |
2793 | const struct btf_param *args; | |
2794 | const struct btf *btf; | |
2795 | u16 nr_args, i; | |
2796 | int err; | |
2797 | ||
2798 | btf = env->btf; | |
2799 | args = (const struct btf_param *)(t + 1); | |
2800 | nr_args = btf_type_vlen(t); | |
2801 | ||
2802 | /* Check func return type which could be "void" (t->type == 0) */ | |
2803 | if (t->type) { | |
2804 | u32 ret_type_id = t->type; | |
2805 | ||
2806 | ret_type = btf_type_by_id(btf, ret_type_id); | |
2807 | if (!ret_type) { | |
2808 | btf_verifier_log_type(env, t, "Invalid return type"); | |
2809 | return -EINVAL; | |
2810 | } | |
2811 | ||
2812 | if (btf_type_needs_resolve(ret_type) && | |
2813 | !env_type_is_resolved(env, ret_type_id)) { | |
2814 | err = btf_resolve(env, ret_type, ret_type_id); | |
2815 | if (err) | |
2816 | return err; | |
2817 | } | |
2818 | ||
2819 | /* Ensure the return type is a type that has a size */ | |
2820 | if (!btf_type_id_size(btf, &ret_type_id, NULL)) { | |
2821 | btf_verifier_log_type(env, t, "Invalid return type"); | |
2822 | return -EINVAL; | |
2823 | } | |
2824 | } | |
2825 | ||
2826 | if (!nr_args) | |
2827 | return 0; | |
2828 | ||
2829 | /* Last func arg type_id could be 0 if it is a vararg */ | |
2830 | if (!args[nr_args - 1].type) { | |
2831 | if (args[nr_args - 1].name_off) { | |
2832 | btf_verifier_log_type(env, t, "Invalid arg#%u", | |
2833 | nr_args); | |
2834 | return -EINVAL; | |
2835 | } | |
2836 | nr_args--; | |
2837 | } | |
2838 | ||
2839 | err = 0; | |
2840 | for (i = 0; i < nr_args; i++) { | |
2841 | const struct btf_type *arg_type; | |
2842 | u32 arg_type_id; | |
2843 | ||
2844 | arg_type_id = args[i].type; | |
2845 | arg_type = btf_type_by_id(btf, arg_type_id); | |
2846 | if (!arg_type) { | |
2847 | btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); | |
2848 | err = -EINVAL; | |
2849 | break; | |
2850 | } | |
2851 | ||
2852 | if (args[i].name_off && | |
2853 | (!btf_name_offset_valid(btf, args[i].name_off) || | |
2854 | !btf_name_valid_identifier(btf, args[i].name_off))) { | |
2855 | btf_verifier_log_type(env, t, | |
2856 | "Invalid arg#%u", i + 1); | |
2857 | err = -EINVAL; | |
2858 | break; | |
2859 | } | |
2860 | ||
2861 | if (btf_type_needs_resolve(arg_type) && | |
2862 | !env_type_is_resolved(env, arg_type_id)) { | |
2863 | err = btf_resolve(env, arg_type, arg_type_id); | |
2864 | if (err) | |
2865 | break; | |
2866 | } | |
2867 | ||
2868 | if (!btf_type_id_size(btf, &arg_type_id, NULL)) { | |
2869 | btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); | |
2870 | err = -EINVAL; | |
2871 | break; | |
2872 | } | |
2873 | } | |
2874 | ||
2875 | return err; | |
2876 | } | |
2877 | ||
2878 | static int btf_func_check(struct btf_verifier_env *env, | |
2879 | const struct btf_type *t) | |
2880 | { | |
2881 | const struct btf_type *proto_type; | |
2882 | const struct btf_param *args; | |
2883 | const struct btf *btf; | |
2884 | u16 nr_args, i; | |
2885 | ||
2886 | btf = env->btf; | |
2887 | proto_type = btf_type_by_id(btf, t->type); | |
2888 | ||
2889 | if (!proto_type || !btf_type_is_func_proto(proto_type)) { | |
2890 | btf_verifier_log_type(env, t, "Invalid type_id"); | |
2891 | return -EINVAL; | |
2892 | } | |
2893 | ||
2894 | args = (const struct btf_param *)(proto_type + 1); | |
2895 | nr_args = btf_type_vlen(proto_type); | |
2896 | for (i = 0; i < nr_args; i++) { | |
2897 | if (!args[i].name_off && args[i].type) { | |
2898 | btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); | |
2899 | return -EINVAL; | |
2900 | } | |
2901 | } | |
2902 | ||
2903 | return 0; | |
2904 | } | |
2905 | ||
69b693f0 MKL |
2906 | static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = { |
2907 | [BTF_KIND_INT] = &int_ops, | |
2908 | [BTF_KIND_PTR] = &ptr_ops, | |
2909 | [BTF_KIND_ARRAY] = &array_ops, | |
2910 | [BTF_KIND_STRUCT] = &struct_ops, | |
2911 | [BTF_KIND_UNION] = &struct_ops, | |
2912 | [BTF_KIND_ENUM] = &enum_ops, | |
2913 | [BTF_KIND_FWD] = &fwd_ops, | |
2914 | [BTF_KIND_TYPEDEF] = &modifier_ops, | |
2915 | [BTF_KIND_VOLATILE] = &modifier_ops, | |
2916 | [BTF_KIND_CONST] = &modifier_ops, | |
2917 | [BTF_KIND_RESTRICT] = &modifier_ops, | |
2667a262 MKL |
2918 | [BTF_KIND_FUNC] = &func_ops, |
2919 | [BTF_KIND_FUNC_PROTO] = &func_proto_ops, | |
1dc92851 DB |
2920 | [BTF_KIND_VAR] = &var_ops, |
2921 | [BTF_KIND_DATASEC] = &datasec_ops, | |
69b693f0 MKL |
2922 | }; |
2923 | ||
2924 | static s32 btf_check_meta(struct btf_verifier_env *env, | |
2925 | const struct btf_type *t, | |
2926 | u32 meta_left) | |
2927 | { | |
2928 | u32 saved_meta_left = meta_left; | |
2929 | s32 var_meta_size; | |
2930 | ||
2931 | if (meta_left < sizeof(*t)) { | |
2932 | btf_verifier_log(env, "[%u] meta_left:%u meta_needed:%zu", | |
2933 | env->log_type_id, meta_left, sizeof(*t)); | |
2934 | return -EINVAL; | |
2935 | } | |
2936 | meta_left -= sizeof(*t); | |
2937 | ||
aea2f7b8 MKL |
2938 | if (t->info & ~BTF_INFO_MASK) { |
2939 | btf_verifier_log(env, "[%u] Invalid btf_info:%x", | |
2940 | env->log_type_id, t->info); | |
2941 | return -EINVAL; | |
2942 | } | |
2943 | ||
69b693f0 MKL |
2944 | if (BTF_INFO_KIND(t->info) > BTF_KIND_MAX || |
2945 | BTF_INFO_KIND(t->info) == BTF_KIND_UNKN) { | |
2946 | btf_verifier_log(env, "[%u] Invalid kind:%u", | |
2947 | env->log_type_id, BTF_INFO_KIND(t->info)); | |
2948 | return -EINVAL; | |
2949 | } | |
2950 | ||
fbcf93eb | 2951 | if (!btf_name_offset_valid(env->btf, t->name_off)) { |
69b693f0 | 2952 | btf_verifier_log(env, "[%u] Invalid name_offset:%u", |
fbcf93eb | 2953 | env->log_type_id, t->name_off); |
69b693f0 MKL |
2954 | return -EINVAL; |
2955 | } | |
2956 | ||
2957 | var_meta_size = btf_type_ops(t)->check_meta(env, t, meta_left); | |
2958 | if (var_meta_size < 0) | |
2959 | return var_meta_size; | |
2960 | ||
2961 | meta_left -= var_meta_size; | |
2962 | ||
2963 | return saved_meta_left - meta_left; | |
2964 | } | |
2965 | ||
2966 | static int btf_check_all_metas(struct btf_verifier_env *env) | |
2967 | { | |
2968 | struct btf *btf = env->btf; | |
2969 | struct btf_header *hdr; | |
2970 | void *cur, *end; | |
2971 | ||
f80442a4 | 2972 | hdr = &btf->hdr; |
69b693f0 | 2973 | cur = btf->nohdr_data + hdr->type_off; |
4b1c5d91 | 2974 | end = cur + hdr->type_len; |
69b693f0 MKL |
2975 | |
2976 | env->log_type_id = 1; | |
2977 | while (cur < end) { | |
2978 | struct btf_type *t = cur; | |
2979 | s32 meta_size; | |
2980 | ||
2981 | meta_size = btf_check_meta(env, t, end - cur); | |
2982 | if (meta_size < 0) | |
2983 | return meta_size; | |
2984 | ||
2985 | btf_add_type(env, t); | |
2986 | cur += meta_size; | |
2987 | env->log_type_id++; | |
2988 | } | |
2989 | ||
2990 | return 0; | |
2991 | } | |
2992 | ||
eb3f595d MKL |
2993 | static bool btf_resolve_valid(struct btf_verifier_env *env, |
2994 | const struct btf_type *t, | |
2995 | u32 type_id) | |
2996 | { | |
2997 | struct btf *btf = env->btf; | |
2998 | ||
2999 | if (!env_type_is_resolved(env, type_id)) | |
3000 | return false; | |
3001 | ||
1dc92851 | 3002 | if (btf_type_is_struct(t) || btf_type_is_datasec(t)) |
eb3f595d | 3003 | return !btf->resolved_ids[type_id] && |
1dc92851 | 3004 | !btf->resolved_sizes[type_id]; |
eb3f595d | 3005 | |
1dc92851 DB |
3006 | if (btf_type_is_modifier(t) || btf_type_is_ptr(t) || |
3007 | btf_type_is_var(t)) { | |
eb3f595d | 3008 | t = btf_type_id_resolve(btf, &type_id); |
1dc92851 DB |
3009 | return t && |
3010 | !btf_type_is_modifier(t) && | |
3011 | !btf_type_is_var(t) && | |
3012 | !btf_type_is_datasec(t); | |
eb3f595d MKL |
3013 | } |
3014 | ||
3015 | if (btf_type_is_array(t)) { | |
3016 | const struct btf_array *array = btf_type_array(t); | |
3017 | const struct btf_type *elem_type; | |
3018 | u32 elem_type_id = array->type; | |
3019 | u32 elem_size; | |
3020 | ||
3021 | elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size); | |
3022 | return elem_type && !btf_type_is_modifier(elem_type) && | |
3023 | (array->nelems * elem_size == | |
3024 | btf->resolved_sizes[type_id]); | |
3025 | } | |
3026 | ||
3027 | return false; | |
3028 | } | |
3029 | ||
2667a262 MKL |
3030 | static int btf_resolve(struct btf_verifier_env *env, |
3031 | const struct btf_type *t, u32 type_id) | |
3032 | { | |
3033 | u32 save_log_type_id = env->log_type_id; | |
3034 | const struct resolve_vertex *v; | |
3035 | int err = 0; | |
3036 | ||
3037 | env->resolve_mode = RESOLVE_TBD; | |
3038 | env_stack_push(env, t, type_id); | |
3039 | while (!err && (v = env_stack_peak(env))) { | |
3040 | env->log_type_id = v->type_id; | |
3041 | err = btf_type_ops(v->t)->resolve(env, v); | |
3042 | } | |
3043 | ||
3044 | env->log_type_id = type_id; | |
3045 | if (err == -E2BIG) { | |
3046 | btf_verifier_log_type(env, t, | |
3047 | "Exceeded max resolving depth:%u", | |
3048 | MAX_RESOLVE_DEPTH); | |
3049 | } else if (err == -EEXIST) { | |
3050 | btf_verifier_log_type(env, t, "Loop detected"); | |
3051 | } | |
3052 | ||
3053 | /* Final sanity check */ | |
3054 | if (!err && !btf_resolve_valid(env, t, type_id)) { | |
3055 | btf_verifier_log_type(env, t, "Invalid resolve state"); | |
3056 | err = -EINVAL; | |
3057 | } | |
3058 | ||
3059 | env->log_type_id = save_log_type_id; | |
3060 | return err; | |
3061 | } | |
3062 | ||
eb3f595d MKL |
3063 | static int btf_check_all_types(struct btf_verifier_env *env) |
3064 | { | |
3065 | struct btf *btf = env->btf; | |
3066 | u32 type_id; | |
3067 | int err; | |
3068 | ||
3069 | err = env_resolve_init(env); | |
3070 | if (err) | |
3071 | return err; | |
3072 | ||
3073 | env->phase++; | |
3074 | for (type_id = 1; type_id <= btf->nr_types; type_id++) { | |
3075 | const struct btf_type *t = btf_type_by_id(btf, type_id); | |
3076 | ||
3077 | env->log_type_id = type_id; | |
3078 | if (btf_type_needs_resolve(t) && | |
3079 | !env_type_is_resolved(env, type_id)) { | |
3080 | err = btf_resolve(env, t, type_id); | |
3081 | if (err) | |
3082 | return err; | |
3083 | } | |
3084 | ||
2667a262 MKL |
3085 | if (btf_type_is_func_proto(t)) { |
3086 | err = btf_func_proto_check(env, t); | |
3087 | if (err) | |
3088 | return err; | |
3089 | } | |
3090 | ||
3091 | if (btf_type_is_func(t)) { | |
3092 | err = btf_func_check(env, t); | |
3093 | if (err) | |
3094 | return err; | |
eb3f595d MKL |
3095 | } |
3096 | } | |
3097 | ||
3098 | return 0; | |
3099 | } | |
3100 | ||
69b693f0 MKL |
3101 | static int btf_parse_type_sec(struct btf_verifier_env *env) |
3102 | { | |
f80442a4 | 3103 | const struct btf_header *hdr = &env->btf->hdr; |
eb3f595d MKL |
3104 | int err; |
3105 | ||
f80442a4 MKL |
3106 | /* Type section must align to 4 bytes */ |
3107 | if (hdr->type_off & (sizeof(u32) - 1)) { | |
3108 | btf_verifier_log(env, "Unaligned type_off"); | |
3109 | return -EINVAL; | |
3110 | } | |
3111 | ||
3112 | if (!hdr->type_len) { | |
3113 | btf_verifier_log(env, "No type found"); | |
3114 | return -EINVAL; | |
3115 | } | |
3116 | ||
eb3f595d MKL |
3117 | err = btf_check_all_metas(env); |
3118 | if (err) | |
3119 | return err; | |
3120 | ||
3121 | return btf_check_all_types(env); | |
69b693f0 MKL |
3122 | } |
3123 | ||
3124 | static int btf_parse_str_sec(struct btf_verifier_env *env) | |
3125 | { | |
3126 | const struct btf_header *hdr; | |
3127 | struct btf *btf = env->btf; | |
3128 | const char *start, *end; | |
3129 | ||
f80442a4 | 3130 | hdr = &btf->hdr; |
69b693f0 MKL |
3131 | start = btf->nohdr_data + hdr->str_off; |
3132 | end = start + hdr->str_len; | |
3133 | ||
f80442a4 MKL |
3134 | if (end != btf->data + btf->data_size) { |
3135 | btf_verifier_log(env, "String section is not at the end"); | |
3136 | return -EINVAL; | |
3137 | } | |
3138 | ||
69b693f0 MKL |
3139 | if (!hdr->str_len || hdr->str_len - 1 > BTF_MAX_NAME_OFFSET || |
3140 | start[0] || end[-1]) { | |
3141 | btf_verifier_log(env, "Invalid string section"); | |
3142 | return -EINVAL; | |
3143 | } | |
3144 | ||
3145 | btf->strings = start; | |
3146 | ||
3147 | return 0; | |
3148 | } | |
3149 | ||
f80442a4 MKL |
3150 | static const size_t btf_sec_info_offset[] = { |
3151 | offsetof(struct btf_header, type_off), | |
3152 | offsetof(struct btf_header, str_off), | |
3153 | }; | |
3154 | ||
3155 | static int btf_sec_info_cmp(const void *a, const void *b) | |
69b693f0 | 3156 | { |
f80442a4 MKL |
3157 | const struct btf_sec_info *x = a; |
3158 | const struct btf_sec_info *y = b; | |
3159 | ||
3160 | return (int)(x->off - y->off) ? : (int)(x->len - y->len); | |
3161 | } | |
3162 | ||
3163 | static int btf_check_sec_info(struct btf_verifier_env *env, | |
3164 | u32 btf_data_size) | |
3165 | { | |
a2889a4c | 3166 | struct btf_sec_info secs[ARRAY_SIZE(btf_sec_info_offset)]; |
f80442a4 | 3167 | u32 total, expected_total, i; |
69b693f0 | 3168 | const struct btf_header *hdr; |
f80442a4 MKL |
3169 | const struct btf *btf; |
3170 | ||
3171 | btf = env->btf; | |
3172 | hdr = &btf->hdr; | |
3173 | ||
3174 | /* Populate the secs from hdr */ | |
a2889a4c | 3175 | for (i = 0; i < ARRAY_SIZE(btf_sec_info_offset); i++) |
f80442a4 MKL |
3176 | secs[i] = *(struct btf_sec_info *)((void *)hdr + |
3177 | btf_sec_info_offset[i]); | |
3178 | ||
a2889a4c MKL |
3179 | sort(secs, ARRAY_SIZE(btf_sec_info_offset), |
3180 | sizeof(struct btf_sec_info), btf_sec_info_cmp, NULL); | |
f80442a4 MKL |
3181 | |
3182 | /* Check for gaps and overlap among sections */ | |
3183 | total = 0; | |
3184 | expected_total = btf_data_size - hdr->hdr_len; | |
a2889a4c | 3185 | for (i = 0; i < ARRAY_SIZE(btf_sec_info_offset); i++) { |
f80442a4 MKL |
3186 | if (expected_total < secs[i].off) { |
3187 | btf_verifier_log(env, "Invalid section offset"); | |
3188 | return -EINVAL; | |
3189 | } | |
3190 | if (total < secs[i].off) { | |
3191 | /* gap */ | |
3192 | btf_verifier_log(env, "Unsupported section found"); | |
3193 | return -EINVAL; | |
3194 | } | |
3195 | if (total > secs[i].off) { | |
3196 | btf_verifier_log(env, "Section overlap found"); | |
3197 | return -EINVAL; | |
3198 | } | |
3199 | if (expected_total - total < secs[i].len) { | |
3200 | btf_verifier_log(env, | |
3201 | "Total section length too long"); | |
3202 | return -EINVAL; | |
3203 | } | |
3204 | total += secs[i].len; | |
3205 | } | |
3206 | ||
3207 | /* There is data other than hdr and known sections */ | |
3208 | if (expected_total != total) { | |
3209 | btf_verifier_log(env, "Unsupported section found"); | |
3210 | return -EINVAL; | |
3211 | } | |
3212 | ||
3213 | return 0; | |
3214 | } | |
3215 | ||
4a6998af | 3216 | static int btf_parse_hdr(struct btf_verifier_env *env) |
f80442a4 | 3217 | { |
4a6998af | 3218 | u32 hdr_len, hdr_copy, btf_data_size; |
f80442a4 | 3219 | const struct btf_header *hdr; |
f80442a4 MKL |
3220 | struct btf *btf; |
3221 | int err; | |
69b693f0 | 3222 | |
f80442a4 | 3223 | btf = env->btf; |
4a6998af | 3224 | btf_data_size = btf->data_size; |
f80442a4 | 3225 | |
4a6998af ML |
3226 | if (btf_data_size < |
3227 | offsetof(struct btf_header, hdr_len) + sizeof(hdr->hdr_len)) { | |
f80442a4 MKL |
3228 | btf_verifier_log(env, "hdr_len not found"); |
3229 | return -EINVAL; | |
3230 | } | |
3231 | ||
4a6998af ML |
3232 | hdr = btf->data; |
3233 | hdr_len = hdr->hdr_len; | |
f80442a4 | 3234 | if (btf_data_size < hdr_len) { |
69b693f0 MKL |
3235 | btf_verifier_log(env, "btf_header not found"); |
3236 | return -EINVAL; | |
3237 | } | |
3238 | ||
4a6998af ML |
3239 | /* Ensure the unsupported header fields are zero */ |
3240 | if (hdr_len > sizeof(btf->hdr)) { | |
3241 | u8 *expected_zero = btf->data + sizeof(btf->hdr); | |
3242 | u8 *end = btf->data + hdr_len; | |
3243 | ||
3244 | for (; expected_zero < end; expected_zero++) { | |
3245 | if (*expected_zero) { | |
3246 | btf_verifier_log(env, "Unsupported btf_header"); | |
3247 | return -E2BIG; | |
3248 | } | |
3249 | } | |
f80442a4 MKL |
3250 | } |
3251 | ||
3252 | hdr_copy = min_t(u32, hdr_len, sizeof(btf->hdr)); | |
4a6998af | 3253 | memcpy(&btf->hdr, btf->data, hdr_copy); |
f80442a4 MKL |
3254 | |
3255 | hdr = &btf->hdr; | |
3256 | ||
3257 | btf_verifier_log_hdr(env, btf_data_size); | |
69b693f0 | 3258 | |
69b693f0 MKL |
3259 | if (hdr->magic != BTF_MAGIC) { |
3260 | btf_verifier_log(env, "Invalid magic"); | |
3261 | return -EINVAL; | |
3262 | } | |
3263 | ||
3264 | if (hdr->version != BTF_VERSION) { | |
3265 | btf_verifier_log(env, "Unsupported version"); | |
3266 | return -ENOTSUPP; | |
3267 | } | |
3268 | ||
3269 | if (hdr->flags) { | |
3270 | btf_verifier_log(env, "Unsupported flags"); | |
3271 | return -ENOTSUPP; | |
3272 | } | |
3273 | ||
f80442a4 | 3274 | if (btf_data_size == hdr->hdr_len) { |
69b693f0 MKL |
3275 | btf_verifier_log(env, "No data"); |
3276 | return -EINVAL; | |
3277 | } | |
3278 | ||
f80442a4 MKL |
3279 | err = btf_check_sec_info(env, btf_data_size); |
3280 | if (err) | |
3281 | return err; | |
69b693f0 MKL |
3282 | |
3283 | return 0; | |
3284 | } | |
3285 | ||
3286 | static struct btf *btf_parse(void __user *btf_data, u32 btf_data_size, | |
3287 | u32 log_level, char __user *log_ubuf, u32 log_size) | |
3288 | { | |
3289 | struct btf_verifier_env *env = NULL; | |
3290 | struct bpf_verifier_log *log; | |
3291 | struct btf *btf = NULL; | |
3292 | u8 *data; | |
3293 | int err; | |
3294 | ||
3295 | if (btf_data_size > BTF_MAX_SIZE) | |
3296 | return ERR_PTR(-E2BIG); | |
3297 | ||
3298 | env = kzalloc(sizeof(*env), GFP_KERNEL | __GFP_NOWARN); | |
3299 | if (!env) | |
3300 | return ERR_PTR(-ENOMEM); | |
3301 | ||
3302 | log = &env->log; | |
3303 | if (log_level || log_ubuf || log_size) { | |
3304 | /* user requested verbose verifier output | |
3305 | * and supplied buffer to store the verification trace | |
3306 | */ | |
3307 | log->level = log_level; | |
3308 | log->ubuf = log_ubuf; | |
3309 | log->len_total = log_size; | |
3310 | ||
3311 | /* log attributes have to be sane */ | |
3312 | if (log->len_total < 128 || log->len_total > UINT_MAX >> 8 || | |
3313 | !log->level || !log->ubuf) { | |
3314 | err = -EINVAL; | |
3315 | goto errout; | |
3316 | } | |
3317 | } | |
3318 | ||
3319 | btf = kzalloc(sizeof(*btf), GFP_KERNEL | __GFP_NOWARN); | |
3320 | if (!btf) { | |
3321 | err = -ENOMEM; | |
3322 | goto errout; | |
3323 | } | |
f80442a4 MKL |
3324 | env->btf = btf; |
3325 | ||
69b693f0 MKL |
3326 | data = kvmalloc(btf_data_size, GFP_KERNEL | __GFP_NOWARN); |
3327 | if (!data) { | |
3328 | err = -ENOMEM; | |
3329 | goto errout; | |
3330 | } | |
3331 | ||
3332 | btf->data = data; | |
3333 | btf->data_size = btf_data_size; | |
3334 | ||
3335 | if (copy_from_user(data, btf_data, btf_data_size)) { | |
3336 | err = -EFAULT; | |
3337 | goto errout; | |
3338 | } | |
3339 | ||
4a6998af ML |
3340 | err = btf_parse_hdr(env); |
3341 | if (err) | |
3342 | goto errout; | |
3343 | ||
3344 | btf->nohdr_data = btf->data + btf->hdr.hdr_len; | |
3345 | ||
69b693f0 MKL |
3346 | err = btf_parse_str_sec(env); |
3347 | if (err) | |
3348 | goto errout; | |
3349 | ||
3350 | err = btf_parse_type_sec(env); | |
3351 | if (err) | |
3352 | goto errout; | |
3353 | ||
f80442a4 | 3354 | if (log->level && bpf_verifier_log_full(log)) { |
69b693f0 MKL |
3355 | err = -ENOSPC; |
3356 | goto errout; | |
3357 | } | |
3358 | ||
f80442a4 MKL |
3359 | btf_verifier_env_free(env); |
3360 | refcount_set(&btf->refcnt, 1); | |
3361 | return btf; | |
69b693f0 MKL |
3362 | |
3363 | errout: | |
3364 | btf_verifier_env_free(env); | |
3365 | if (btf) | |
3366 | btf_free(btf); | |
3367 | return ERR_PTR(err); | |
3368 | } | |
b00b8dae MKL |
3369 | |
3370 | void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj, | |
3371 | struct seq_file *m) | |
3372 | { | |
3373 | const struct btf_type *t = btf_type_by_id(btf, type_id); | |
3374 | ||
3375 | btf_type_ops(t)->seq_show(btf, t, type_id, obj, 0, m); | |
3376 | } | |
f56a653c | 3377 | |
3481e64b QM |
3378 | #ifdef CONFIG_PROC_FS |
3379 | static void bpf_btf_show_fdinfo(struct seq_file *m, struct file *filp) | |
3380 | { | |
3381 | const struct btf *btf = filp->private_data; | |
3382 | ||
3383 | seq_printf(m, "btf_id:\t%u\n", btf->id); | |
3384 | } | |
3385 | #endif | |
3386 | ||
f56a653c MKL |
3387 | static int btf_release(struct inode *inode, struct file *filp) |
3388 | { | |
3389 | btf_put(filp->private_data); | |
3390 | return 0; | |
3391 | } | |
3392 | ||
60197cfb | 3393 | const struct file_operations btf_fops = { |
3481e64b QM |
3394 | #ifdef CONFIG_PROC_FS |
3395 | .show_fdinfo = bpf_btf_show_fdinfo, | |
3396 | #endif | |
f56a653c MKL |
3397 | .release = btf_release, |
3398 | }; | |
3399 | ||
78958fca MKL |
3400 | static int __btf_new_fd(struct btf *btf) |
3401 | { | |
3402 | return anon_inode_getfd("btf", &btf_fops, btf, O_RDONLY | O_CLOEXEC); | |
3403 | } | |
3404 | ||
f56a653c MKL |
3405 | int btf_new_fd(const union bpf_attr *attr) |
3406 | { | |
3407 | struct btf *btf; | |
78958fca | 3408 | int ret; |
f56a653c MKL |
3409 | |
3410 | btf = btf_parse(u64_to_user_ptr(attr->btf), | |
3411 | attr->btf_size, attr->btf_log_level, | |
3412 | u64_to_user_ptr(attr->btf_log_buf), | |
3413 | attr->btf_log_size); | |
3414 | if (IS_ERR(btf)) | |
3415 | return PTR_ERR(btf); | |
3416 | ||
78958fca MKL |
3417 | ret = btf_alloc_id(btf); |
3418 | if (ret) { | |
3419 | btf_free(btf); | |
3420 | return ret; | |
3421 | } | |
3422 | ||
3423 | /* | |
3424 | * The BTF ID is published to the userspace. | |
3425 | * All BTF free must go through call_rcu() from | |
3426 | * now on (i.e. free by calling btf_put()). | |
3427 | */ | |
3428 | ||
3429 | ret = __btf_new_fd(btf); | |
3430 | if (ret < 0) | |
f56a653c MKL |
3431 | btf_put(btf); |
3432 | ||
78958fca | 3433 | return ret; |
f56a653c MKL |
3434 | } |
3435 | ||
3436 | struct btf *btf_get_by_fd(int fd) | |
3437 | { | |
3438 | struct btf *btf; | |
3439 | struct fd f; | |
3440 | ||
3441 | f = fdget(fd); | |
3442 | ||
3443 | if (!f.file) | |
3444 | return ERR_PTR(-EBADF); | |
3445 | ||
3446 | if (f.file->f_op != &btf_fops) { | |
3447 | fdput(f); | |
3448 | return ERR_PTR(-EINVAL); | |
3449 | } | |
3450 | ||
3451 | btf = f.file->private_data; | |
78958fca | 3452 | refcount_inc(&btf->refcnt); |
f56a653c MKL |
3453 | fdput(f); |
3454 | ||
3455 | return btf; | |
3456 | } | |
60197cfb MKL |
3457 | |
3458 | int btf_get_info_by_fd(const struct btf *btf, | |
3459 | const union bpf_attr *attr, | |
3460 | union bpf_attr __user *uattr) | |
3461 | { | |
62dab84c MKL |
3462 | struct bpf_btf_info __user *uinfo; |
3463 | struct bpf_btf_info info = {}; | |
3464 | u32 info_copy, btf_copy; | |
3465 | void __user *ubtf; | |
3466 | u32 uinfo_len; | |
60197cfb | 3467 | |
62dab84c MKL |
3468 | uinfo = u64_to_user_ptr(attr->info.info); |
3469 | uinfo_len = attr->info.info_len; | |
3470 | ||
3471 | info_copy = min_t(u32, uinfo_len, sizeof(info)); | |
3472 | if (copy_from_user(&info, uinfo, info_copy)) | |
3473 | return -EFAULT; | |
3474 | ||
3475 | info.id = btf->id; | |
3476 | ubtf = u64_to_user_ptr(info.btf); | |
3477 | btf_copy = min_t(u32, btf->data_size, info.btf_size); | |
3478 | if (copy_to_user(ubtf, btf->data, btf_copy)) | |
3479 | return -EFAULT; | |
3480 | info.btf_size = btf->data_size; | |
3481 | ||
3482 | if (copy_to_user(uinfo, &info, info_copy) || | |
3483 | put_user(info_copy, &uattr->info.info_len)) | |
60197cfb MKL |
3484 | return -EFAULT; |
3485 | ||
3486 | return 0; | |
3487 | } | |
78958fca MKL |
3488 | |
3489 | int btf_get_fd_by_id(u32 id) | |
3490 | { | |
3491 | struct btf *btf; | |
3492 | int fd; | |
3493 | ||
3494 | rcu_read_lock(); | |
3495 | btf = idr_find(&btf_idr, id); | |
3496 | if (!btf || !refcount_inc_not_zero(&btf->refcnt)) | |
3497 | btf = ERR_PTR(-ENOENT); | |
3498 | rcu_read_unlock(); | |
3499 | ||
3500 | if (IS_ERR(btf)) | |
3501 | return PTR_ERR(btf); | |
3502 | ||
3503 | fd = __btf_new_fd(btf); | |
3504 | if (fd < 0) | |
3505 | btf_put(btf); | |
3506 | ||
3507 | return fd; | |
3508 | } | |
3509 | ||
3510 | u32 btf_id(const struct btf *btf) | |
3511 | { | |
3512 | return btf->id; | |
3513 | } |