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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
f5bffecd AS |
2 | /* |
3 | * Linux Socket Filter - Kernel level socket filtering | |
4 | * | |
5 | * Based on the design of the Berkeley Packet Filter. The new | |
6 | * internal format has been designed by PLUMgrid: | |
7 | * | |
8 | * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com | |
9 | * | |
10 | * Authors: | |
11 | * | |
12 | * Jay Schulist <jschlst@samba.org> | |
13 | * Alexei Starovoitov <ast@plumgrid.com> | |
14 | * Daniel Borkmann <dborkman@redhat.com> | |
15 | * | |
f5bffecd | 16 | * Andi Kleen - Fix a few bad bugs and races. |
4df95ff4 | 17 | * Kris Katterjohn - Added many additional checks in bpf_check_classic() |
f5bffecd | 18 | */ |
738cbe72 | 19 | |
838e9690 | 20 | #include <uapi/linux/btf.h> |
f5bffecd AS |
21 | #include <linux/filter.h> |
22 | #include <linux/skbuff.h> | |
60a3b225 | 23 | #include <linux/vmalloc.h> |
738cbe72 DB |
24 | #include <linux/random.h> |
25 | #include <linux/moduleloader.h> | |
09756af4 | 26 | #include <linux/bpf.h> |
838e9690 | 27 | #include <linux/btf.h> |
00089c04 | 28 | #include <linux/objtool.h> |
74451e66 DB |
29 | #include <linux/rbtree_latch.h> |
30 | #include <linux/kallsyms.h> | |
31 | #include <linux/rcupdate.h> | |
c195651e | 32 | #include <linux/perf_event.h> |
3dec541b | 33 | #include <linux/extable.h> |
b7b3fc8d | 34 | #include <linux/log2.h> |
2357672c | 35 | #include <linux/bpf_verifier.h> |
ef078600 | 36 | #include <linux/nodemask.h> |
f3dd0c53 | 37 | #include <linux/nospec.h> |
958cf2e2 | 38 | #include <linux/bpf_mem_alloc.h> |
bf396508 | 39 | #include <linux/memcontrol.h> |
f5e81d11 DB |
40 | |
41 | #include <asm/barrier.h> | |
3324b584 DB |
42 | #include <asm/unaligned.h> |
43 | ||
f5bffecd AS |
44 | /* Registers */ |
45 | #define BPF_R0 regs[BPF_REG_0] | |
46 | #define BPF_R1 regs[BPF_REG_1] | |
47 | #define BPF_R2 regs[BPF_REG_2] | |
48 | #define BPF_R3 regs[BPF_REG_3] | |
49 | #define BPF_R4 regs[BPF_REG_4] | |
50 | #define BPF_R5 regs[BPF_REG_5] | |
51 | #define BPF_R6 regs[BPF_REG_6] | |
52 | #define BPF_R7 regs[BPF_REG_7] | |
53 | #define BPF_R8 regs[BPF_REG_8] | |
54 | #define BPF_R9 regs[BPF_REG_9] | |
55 | #define BPF_R10 regs[BPF_REG_10] | |
56 | ||
57 | /* Named registers */ | |
58 | #define DST regs[insn->dst_reg] | |
59 | #define SRC regs[insn->src_reg] | |
60 | #define FP regs[BPF_REG_FP] | |
144cd91c | 61 | #define AX regs[BPF_REG_AX] |
f5bffecd AS |
62 | #define ARG1 regs[BPF_REG_ARG1] |
63 | #define CTX regs[BPF_REG_CTX] | |
8100928c | 64 | #define OFF insn->off |
f5bffecd AS |
65 | #define IMM insn->imm |
66 | ||
1fda5bb6 YS |
67 | struct bpf_mem_alloc bpf_global_ma; |
68 | bool bpf_global_ma_set; | |
958cf2e2 | 69 | |
f5bffecd AS |
70 | /* No hurry in this branch |
71 | * | |
72 | * Exported for the bpf jit load helper. | |
73 | */ | |
74 | void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, unsigned int size) | |
75 | { | |
76 | u8 *ptr = NULL; | |
77 | ||
0326195f | 78 | if (k >= SKF_NET_OFF) { |
f5bffecd | 79 | ptr = skb_network_header(skb) + k - SKF_NET_OFF; |
0326195f ED |
80 | } else if (k >= SKF_LL_OFF) { |
81 | if (unlikely(!skb_mac_header_was_set(skb))) | |
82 | return NULL; | |
f5bffecd | 83 | ptr = skb_mac_header(skb) + k - SKF_LL_OFF; |
0326195f | 84 | } |
f5bffecd AS |
85 | if (ptr >= skb->head && ptr + size <= skb_tail_pointer(skb)) |
86 | return ptr; | |
87 | ||
88 | return NULL; | |
89 | } | |
90 | ||
492ecee8 | 91 | struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags) |
60a3b225 | 92 | { |
bf396508 | 93 | gfp_t gfp_flags = bpf_memcg_flags(GFP_KERNEL | __GFP_ZERO | gfp_extra_flags); |
09756af4 | 94 | struct bpf_prog_aux *aux; |
60a3b225 DB |
95 | struct bpf_prog *fp; |
96 | ||
97 | size = round_up(size, PAGE_SIZE); | |
88dca4ca | 98 | fp = __vmalloc(size, gfp_flags); |
60a3b225 DB |
99 | if (fp == NULL) |
100 | return NULL; | |
101 | ||
bf396508 | 102 | aux = kzalloc(sizeof(*aux), bpf_memcg_flags(GFP_KERNEL | gfp_extra_flags)); |
09756af4 | 103 | if (aux == NULL) { |
60a3b225 DB |
104 | vfree(fp); |
105 | return NULL; | |
106 | } | |
bf396508 | 107 | fp->active = alloc_percpu_gfp(int, bpf_memcg_flags(GFP_KERNEL | gfp_extra_flags)); |
ca06f55b AS |
108 | if (!fp->active) { |
109 | vfree(fp); | |
110 | kfree(aux); | |
111 | return NULL; | |
112 | } | |
60a3b225 DB |
113 | |
114 | fp->pages = size / PAGE_SIZE; | |
09756af4 | 115 | fp->aux = aux; |
e9d8afa9 | 116 | fp->aux->prog = fp; |
60b58afc | 117 | fp->jit_requested = ebpf_jit_enabled(); |
d2a3b7c5 | 118 | fp->blinding_requested = bpf_jit_blinding_enabled(fp); |
c0e19f2c SF |
119 | #ifdef CONFIG_CGROUP_BPF |
120 | aux->cgroup_atype = CGROUP_BPF_ATTACH_TYPE_INVALID; | |
121 | #endif | |
60a3b225 | 122 | |
ecb60d1c | 123 | INIT_LIST_HEAD_RCU(&fp->aux->ksym.lnode); |
984fe94f | 124 | mutex_init(&fp->aux->used_maps_mutex); |
3aac1ead | 125 | mutex_init(&fp->aux->dst_mutex); |
74451e66 | 126 | |
60a3b225 DB |
127 | return fp; |
128 | } | |
492ecee8 AS |
129 | |
130 | struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags) | |
131 | { | |
bf396508 | 132 | gfp_t gfp_flags = bpf_memcg_flags(GFP_KERNEL | __GFP_ZERO | gfp_extra_flags); |
492ecee8 | 133 | struct bpf_prog *prog; |
4b911304 | 134 | int cpu; |
492ecee8 AS |
135 | |
136 | prog = bpf_prog_alloc_no_stats(size, gfp_extra_flags); | |
137 | if (!prog) | |
138 | return NULL; | |
139 | ||
700d4796 AS |
140 | prog->stats = alloc_percpu_gfp(struct bpf_prog_stats, gfp_flags); |
141 | if (!prog->stats) { | |
ca06f55b | 142 | free_percpu(prog->active); |
492ecee8 AS |
143 | kfree(prog->aux); |
144 | vfree(prog); | |
145 | return NULL; | |
146 | } | |
147 | ||
4b911304 ED |
148 | for_each_possible_cpu(cpu) { |
149 | struct bpf_prog_stats *pstats; | |
150 | ||
700d4796 | 151 | pstats = per_cpu_ptr(prog->stats, cpu); |
4b911304 ED |
152 | u64_stats_init(&pstats->syncp); |
153 | } | |
492ecee8 AS |
154 | return prog; |
155 | } | |
60a3b225 DB |
156 | EXPORT_SYMBOL_GPL(bpf_prog_alloc); |
157 | ||
c454a46b MKL |
158 | int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog) |
159 | { | |
160 | if (!prog->aux->nr_linfo || !prog->jit_requested) | |
161 | return 0; | |
162 | ||
e16301fb MKL |
163 | prog->aux->jited_linfo = kvcalloc(prog->aux->nr_linfo, |
164 | sizeof(*prog->aux->jited_linfo), | |
bf396508 | 165 | bpf_memcg_flags(GFP_KERNEL | __GFP_NOWARN)); |
c454a46b MKL |
166 | if (!prog->aux->jited_linfo) |
167 | return -ENOMEM; | |
168 | ||
169 | return 0; | |
170 | } | |
171 | ||
e16301fb | 172 | void bpf_prog_jit_attempt_done(struct bpf_prog *prog) |
c454a46b | 173 | { |
e16301fb MKL |
174 | if (prog->aux->jited_linfo && |
175 | (!prog->jited || !prog->aux->jited_linfo[0])) { | |
176 | kvfree(prog->aux->jited_linfo); | |
177 | prog->aux->jited_linfo = NULL; | |
178 | } | |
e6ac2450 MKL |
179 | |
180 | kfree(prog->aux->kfunc_tab); | |
181 | prog->aux->kfunc_tab = NULL; | |
c454a46b MKL |
182 | } |
183 | ||
184 | /* The jit engine is responsible to provide an array | |
185 | * for insn_off to the jited_off mapping (insn_to_jit_off). | |
186 | * | |
187 | * The idx to this array is the insn_off. Hence, the insn_off | |
188 | * here is relative to the prog itself instead of the main prog. | |
189 | * This array has one entry for each xlated bpf insn. | |
190 | * | |
cc168554 | 191 | * jited_off is the byte off to the end of the jited insn. |
c454a46b MKL |
192 | * |
193 | * Hence, with | |
194 | * insn_start: | |
195 | * The first bpf insn off of the prog. The insn off | |
196 | * here is relative to the main prog. | |
197 | * e.g. if prog is a subprog, insn_start > 0 | |
198 | * linfo_idx: | |
199 | * The prog's idx to prog->aux->linfo and jited_linfo | |
200 | * | |
201 | * jited_linfo[linfo_idx] = prog->bpf_func | |
202 | * | |
203 | * For i > linfo_idx, | |
204 | * | |
205 | * jited_linfo[i] = prog->bpf_func + | |
206 | * insn_to_jit_off[linfo[i].insn_off - insn_start - 1] | |
207 | */ | |
208 | void bpf_prog_fill_jited_linfo(struct bpf_prog *prog, | |
209 | const u32 *insn_to_jit_off) | |
210 | { | |
211 | u32 linfo_idx, insn_start, insn_end, nr_linfo, i; | |
212 | const struct bpf_line_info *linfo; | |
213 | void **jited_linfo; | |
214 | ||
335d1c5b | 215 | if (!prog->aux->jited_linfo || prog->aux->func_idx > prog->aux->func_cnt) |
c454a46b MKL |
216 | /* Userspace did not provide linfo */ |
217 | return; | |
218 | ||
219 | linfo_idx = prog->aux->linfo_idx; | |
220 | linfo = &prog->aux->linfo[linfo_idx]; | |
221 | insn_start = linfo[0].insn_off; | |
222 | insn_end = insn_start + prog->len; | |
223 | ||
224 | jited_linfo = &prog->aux->jited_linfo[linfo_idx]; | |
225 | jited_linfo[0] = prog->bpf_func; | |
226 | ||
227 | nr_linfo = prog->aux->nr_linfo - linfo_idx; | |
228 | ||
229 | for (i = 1; i < nr_linfo && linfo[i].insn_off < insn_end; i++) | |
230 | /* The verifier ensures that linfo[i].insn_off is | |
231 | * strictly increasing | |
232 | */ | |
233 | jited_linfo[i] = prog->bpf_func + | |
234 | insn_to_jit_off[linfo[i].insn_off - insn_start - 1]; | |
235 | } | |
236 | ||
60a3b225 DB |
237 | struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, |
238 | gfp_t gfp_extra_flags) | |
239 | { | |
bf396508 | 240 | gfp_t gfp_flags = bpf_memcg_flags(GFP_KERNEL | __GFP_ZERO | gfp_extra_flags); |
60a3b225 | 241 | struct bpf_prog *fp; |
3ac1f01b | 242 | u32 pages; |
60a3b225 | 243 | |
60a3b225 | 244 | size = round_up(size, PAGE_SIZE); |
5ccb071e DB |
245 | pages = size / PAGE_SIZE; |
246 | if (pages <= fp_old->pages) | |
60a3b225 DB |
247 | return fp_old; |
248 | ||
88dca4ca | 249 | fp = __vmalloc(size, gfp_flags); |
3ac1f01b | 250 | if (fp) { |
60a3b225 | 251 | memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE); |
5ccb071e | 252 | fp->pages = pages; |
e9d8afa9 | 253 | fp->aux->prog = fp; |
60a3b225 | 254 | |
09756af4 | 255 | /* We keep fp->aux from fp_old around in the new |
60a3b225 DB |
256 | * reallocated structure. |
257 | */ | |
09756af4 | 258 | fp_old->aux = NULL; |
1336c662 AS |
259 | fp_old->stats = NULL; |
260 | fp_old->active = NULL; | |
60a3b225 DB |
261 | __bpf_prog_free(fp_old); |
262 | } | |
263 | ||
264 | return fp; | |
265 | } | |
60a3b225 DB |
266 | |
267 | void __bpf_prog_free(struct bpf_prog *fp) | |
268 | { | |
492ecee8 | 269 | if (fp->aux) { |
984fe94f | 270 | mutex_destroy(&fp->aux->used_maps_mutex); |
3aac1ead | 271 | mutex_destroy(&fp->aux->dst_mutex); |
a66886fe | 272 | kfree(fp->aux->poke_tab); |
492ecee8 AS |
273 | kfree(fp->aux); |
274 | } | |
700d4796 | 275 | free_percpu(fp->stats); |
ca06f55b | 276 | free_percpu(fp->active); |
60a3b225 DB |
277 | vfree(fp); |
278 | } | |
60a3b225 | 279 | |
f1f7714e | 280 | int bpf_prog_calc_tag(struct bpf_prog *fp) |
7bd509e3 | 281 | { |
6b0b0fa2 | 282 | const u32 bits_offset = SHA1_BLOCK_SIZE - sizeof(__be64); |
f1f7714e | 283 | u32 raw_size = bpf_prog_tag_scratch_size(fp); |
6b0b0fa2 EB |
284 | u32 digest[SHA1_DIGEST_WORDS]; |
285 | u32 ws[SHA1_WORKSPACE_WORDS]; | |
7bd509e3 | 286 | u32 i, bsize, psize, blocks; |
aafe6ae9 | 287 | struct bpf_insn *dst; |
7bd509e3 | 288 | bool was_ld_map; |
aafe6ae9 | 289 | u8 *raw, *todo; |
7bd509e3 DB |
290 | __be32 *result; |
291 | __be64 *bits; | |
292 | ||
aafe6ae9 DB |
293 | raw = vmalloc(raw_size); |
294 | if (!raw) | |
295 | return -ENOMEM; | |
296 | ||
6b0b0fa2 | 297 | sha1_init(digest); |
7bd509e3 DB |
298 | memset(ws, 0, sizeof(ws)); |
299 | ||
300 | /* We need to take out the map fd for the digest calculation | |
301 | * since they are unstable from user space side. | |
302 | */ | |
aafe6ae9 | 303 | dst = (void *)raw; |
7bd509e3 DB |
304 | for (i = 0, was_ld_map = false; i < fp->len; i++) { |
305 | dst[i] = fp->insnsi[i]; | |
306 | if (!was_ld_map && | |
307 | dst[i].code == (BPF_LD | BPF_IMM | BPF_DW) && | |
d8eca5bb DB |
308 | (dst[i].src_reg == BPF_PSEUDO_MAP_FD || |
309 | dst[i].src_reg == BPF_PSEUDO_MAP_VALUE)) { | |
7bd509e3 DB |
310 | was_ld_map = true; |
311 | dst[i].imm = 0; | |
312 | } else if (was_ld_map && | |
313 | dst[i].code == 0 && | |
314 | dst[i].dst_reg == 0 && | |
315 | dst[i].src_reg == 0 && | |
316 | dst[i].off == 0) { | |
317 | was_ld_map = false; | |
318 | dst[i].imm = 0; | |
319 | } else { | |
320 | was_ld_map = false; | |
321 | } | |
322 | } | |
323 | ||
aafe6ae9 DB |
324 | psize = bpf_prog_insn_size(fp); |
325 | memset(&raw[psize], 0, raw_size - psize); | |
7bd509e3 DB |
326 | raw[psize++] = 0x80; |
327 | ||
6b0b0fa2 EB |
328 | bsize = round_up(psize, SHA1_BLOCK_SIZE); |
329 | blocks = bsize / SHA1_BLOCK_SIZE; | |
aafe6ae9 | 330 | todo = raw; |
7bd509e3 DB |
331 | if (bsize - psize >= sizeof(__be64)) { |
332 | bits = (__be64 *)(todo + bsize - sizeof(__be64)); | |
333 | } else { | |
334 | bits = (__be64 *)(todo + bsize + bits_offset); | |
335 | blocks++; | |
336 | } | |
337 | *bits = cpu_to_be64((psize - 1) << 3); | |
338 | ||
339 | while (blocks--) { | |
6b0b0fa2 EB |
340 | sha1_transform(digest, todo, ws); |
341 | todo += SHA1_BLOCK_SIZE; | |
7bd509e3 DB |
342 | } |
343 | ||
f1f7714e | 344 | result = (__force __be32 *)digest; |
6b0b0fa2 | 345 | for (i = 0; i < SHA1_DIGEST_WORDS; i++) |
f1f7714e DB |
346 | result[i] = cpu_to_be32(digest[i]); |
347 | memcpy(fp->tag, result, sizeof(fp->tag)); | |
aafe6ae9 DB |
348 | |
349 | vfree(raw); | |
350 | return 0; | |
7bd509e3 DB |
351 | } |
352 | ||
2cbd95a5 | 353 | static int bpf_adj_delta_to_imm(struct bpf_insn *insn, u32 pos, s32 end_old, |
af959b18 | 354 | s32 end_new, s32 curr, const bool probe_pass) |
c237ee5e | 355 | { |
050fad7c | 356 | const s64 imm_min = S32_MIN, imm_max = S32_MAX; |
2cbd95a5 | 357 | s32 delta = end_new - end_old; |
050fad7c DB |
358 | s64 imm = insn->imm; |
359 | ||
2cbd95a5 | 360 | if (curr < pos && curr + imm + 1 >= end_old) |
050fad7c | 361 | imm += delta; |
2cbd95a5 | 362 | else if (curr >= end_new && curr + imm + 1 < end_new) |
050fad7c DB |
363 | imm -= delta; |
364 | if (imm < imm_min || imm > imm_max) | |
365 | return -ERANGE; | |
366 | if (!probe_pass) | |
367 | insn->imm = imm; | |
368 | return 0; | |
369 | } | |
370 | ||
2cbd95a5 | 371 | static int bpf_adj_delta_to_off(struct bpf_insn *insn, u32 pos, s32 end_old, |
af959b18 | 372 | s32 end_new, s32 curr, const bool probe_pass) |
050fad7c | 373 | { |
dfce9cb3 | 374 | s64 off_min, off_max, off; |
2cbd95a5 | 375 | s32 delta = end_new - end_old; |
4cd58e9a | 376 | |
dfce9cb3 | 377 | if (insn->code == (BPF_JMP32 | BPF_JA)) { |
4cd58e9a | 378 | off = insn->imm; |
dfce9cb3 YS |
379 | off_min = S32_MIN; |
380 | off_max = S32_MAX; | |
381 | } else { | |
4cd58e9a | 382 | off = insn->off; |
dfce9cb3 YS |
383 | off_min = S16_MIN; |
384 | off_max = S16_MAX; | |
385 | } | |
050fad7c | 386 | |
2cbd95a5 | 387 | if (curr < pos && curr + off + 1 >= end_old) |
050fad7c | 388 | off += delta; |
2cbd95a5 | 389 | else if (curr >= end_new && curr + off + 1 < end_new) |
050fad7c DB |
390 | off -= delta; |
391 | if (off < off_min || off > off_max) | |
392 | return -ERANGE; | |
4cd58e9a YS |
393 | if (!probe_pass) { |
394 | if (insn->code == (BPF_JMP32 | BPF_JA)) | |
395 | insn->imm = off; | |
396 | else | |
397 | insn->off = off; | |
398 | } | |
050fad7c DB |
399 | return 0; |
400 | } | |
401 | ||
2cbd95a5 JK |
402 | static int bpf_adj_branches(struct bpf_prog *prog, u32 pos, s32 end_old, |
403 | s32 end_new, const bool probe_pass) | |
050fad7c | 404 | { |
2cbd95a5 | 405 | u32 i, insn_cnt = prog->len + (probe_pass ? end_new - end_old : 0); |
c237ee5e | 406 | struct bpf_insn *insn = prog->insnsi; |
050fad7c | 407 | int ret = 0; |
c237ee5e DB |
408 | |
409 | for (i = 0; i < insn_cnt; i++, insn++) { | |
050fad7c DB |
410 | u8 code; |
411 | ||
412 | /* In the probing pass we still operate on the original, | |
413 | * unpatched image in order to check overflows before we | |
414 | * do any other adjustments. Therefore skip the patchlet. | |
415 | */ | |
416 | if (probe_pass && i == pos) { | |
2cbd95a5 JK |
417 | i = end_new; |
418 | insn = prog->insnsi + end_old; | |
050fad7c | 419 | } |
3990ed4c MKL |
420 | if (bpf_pseudo_func(insn)) { |
421 | ret = bpf_adj_delta_to_imm(insn, pos, end_old, | |
422 | end_new, i, probe_pass); | |
423 | if (ret) | |
424 | return ret; | |
425 | continue; | |
426 | } | |
1ea47e01 | 427 | code = insn->code; |
092ed096 JW |
428 | if ((BPF_CLASS(code) != BPF_JMP && |
429 | BPF_CLASS(code) != BPF_JMP32) || | |
050fad7c | 430 | BPF_OP(code) == BPF_EXIT) |
1ea47e01 | 431 | continue; |
050fad7c | 432 | /* Adjust offset of jmps if we cross patch boundaries. */ |
1ea47e01 | 433 | if (BPF_OP(code) == BPF_CALL) { |
050fad7c | 434 | if (insn->src_reg != BPF_PSEUDO_CALL) |
1ea47e01 | 435 | continue; |
2cbd95a5 JK |
436 | ret = bpf_adj_delta_to_imm(insn, pos, end_old, |
437 | end_new, i, probe_pass); | |
1ea47e01 | 438 | } else { |
2cbd95a5 JK |
439 | ret = bpf_adj_delta_to_off(insn, pos, end_old, |
440 | end_new, i, probe_pass); | |
1ea47e01 | 441 | } |
050fad7c DB |
442 | if (ret) |
443 | break; | |
c237ee5e | 444 | } |
050fad7c DB |
445 | |
446 | return ret; | |
c237ee5e DB |
447 | } |
448 | ||
c454a46b MKL |
449 | static void bpf_adj_linfo(struct bpf_prog *prog, u32 off, u32 delta) |
450 | { | |
451 | struct bpf_line_info *linfo; | |
452 | u32 i, nr_linfo; | |
453 | ||
454 | nr_linfo = prog->aux->nr_linfo; | |
455 | if (!nr_linfo || !delta) | |
456 | return; | |
457 | ||
458 | linfo = prog->aux->linfo; | |
459 | ||
460 | for (i = 0; i < nr_linfo; i++) | |
461 | if (off < linfo[i].insn_off) | |
462 | break; | |
463 | ||
464 | /* Push all off < linfo[i].insn_off by delta */ | |
465 | for (; i < nr_linfo; i++) | |
466 | linfo[i].insn_off += delta; | |
467 | } | |
468 | ||
c237ee5e DB |
469 | struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, |
470 | const struct bpf_insn *patch, u32 len) | |
471 | { | |
472 | u32 insn_adj_cnt, insn_rest, insn_delta = len - 1; | |
050fad7c | 473 | const u32 cnt_max = S16_MAX; |
c237ee5e | 474 | struct bpf_prog *prog_adj; |
4f73379e | 475 | int err; |
c237ee5e DB |
476 | |
477 | /* Since our patchlet doesn't expand the image, we're done. */ | |
478 | if (insn_delta == 0) { | |
479 | memcpy(prog->insnsi + off, patch, sizeof(*patch)); | |
480 | return prog; | |
481 | } | |
482 | ||
483 | insn_adj_cnt = prog->len + insn_delta; | |
484 | ||
050fad7c DB |
485 | /* Reject anything that would potentially let the insn->off |
486 | * target overflow when we have excessive program expansions. | |
487 | * We need to probe here before we do any reallocation where | |
488 | * we afterwards may not fail anymore. | |
489 | */ | |
490 | if (insn_adj_cnt > cnt_max && | |
4f73379e AS |
491 | (err = bpf_adj_branches(prog, off, off + 1, off + len, true))) |
492 | return ERR_PTR(err); | |
050fad7c | 493 | |
c237ee5e DB |
494 | /* Several new instructions need to be inserted. Make room |
495 | * for them. Likely, there's no need for a new allocation as | |
496 | * last page could have large enough tailroom. | |
497 | */ | |
498 | prog_adj = bpf_prog_realloc(prog, bpf_prog_size(insn_adj_cnt), | |
499 | GFP_USER); | |
500 | if (!prog_adj) | |
4f73379e | 501 | return ERR_PTR(-ENOMEM); |
c237ee5e DB |
502 | |
503 | prog_adj->len = insn_adj_cnt; | |
504 | ||
505 | /* Patching happens in 3 steps: | |
506 | * | |
507 | * 1) Move over tail of insnsi from next instruction onwards, | |
508 | * so we can patch the single target insn with one or more | |
509 | * new ones (patching is always from 1 to n insns, n > 0). | |
510 | * 2) Inject new instructions at the target location. | |
511 | * 3) Adjust branch offsets if necessary. | |
512 | */ | |
513 | insn_rest = insn_adj_cnt - off - len; | |
514 | ||
515 | memmove(prog_adj->insnsi + off + len, prog_adj->insnsi + off + 1, | |
516 | sizeof(*patch) * insn_rest); | |
517 | memcpy(prog_adj->insnsi + off, patch, sizeof(*patch) * len); | |
518 | ||
050fad7c DB |
519 | /* We are guaranteed to not fail at this point, otherwise |
520 | * the ship has sailed to reverse to the original state. An | |
521 | * overflow cannot happen at this point. | |
522 | */ | |
2cbd95a5 | 523 | BUG_ON(bpf_adj_branches(prog_adj, off, off + 1, off + len, false)); |
c237ee5e | 524 | |
c454a46b MKL |
525 | bpf_adj_linfo(prog_adj, off, insn_delta); |
526 | ||
c237ee5e DB |
527 | return prog_adj; |
528 | } | |
529 | ||
52875a04 JK |
530 | int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt) |
531 | { | |
532 | /* Branch offsets can't overflow when program is shrinking, no need | |
533 | * to call bpf_adj_branches(..., true) here | |
534 | */ | |
535 | memmove(prog->insnsi + off, prog->insnsi + off + cnt, | |
536 | sizeof(struct bpf_insn) * (prog->len - off - cnt)); | |
537 | prog->len -= cnt; | |
538 | ||
539 | return WARN_ON_ONCE(bpf_adj_branches(prog, off, off + cnt, off, false)); | |
540 | } | |
541 | ||
cd7455f1 | 542 | static void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp) |
7d1982b4 DB |
543 | { |
544 | int i; | |
545 | ||
335d1c5b | 546 | for (i = 0; i < fp->aux->real_func_cnt; i++) |
7d1982b4 DB |
547 | bpf_prog_kallsyms_del(fp->aux->func[i]); |
548 | } | |
549 | ||
550 | void bpf_prog_kallsyms_del_all(struct bpf_prog *fp) | |
551 | { | |
552 | bpf_prog_kallsyms_del_subprogs(fp); | |
553 | bpf_prog_kallsyms_del(fp); | |
554 | } | |
555 | ||
b954d834 | 556 | #ifdef CONFIG_BPF_JIT |
fa9dd599 | 557 | /* All BPF JIT sysctl knobs here. */ |
81c22041 DB |
558 | int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_DEFAULT_ON); |
559 | int bpf_jit_kallsyms __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_DEFAULT_ON); | |
fa9dd599 | 560 | int bpf_jit_harden __read_mostly; |
fdadd049 | 561 | long bpf_jit_limit __read_mostly; |
fadb7ff1 | 562 | long bpf_jit_limit_max __read_mostly; |
fa9dd599 | 563 | |
535911c8 JO |
564 | static void |
565 | bpf_prog_ksym_set_addr(struct bpf_prog *prog) | |
74451e66 | 566 | { |
74451e66 DB |
567 | WARN_ON_ONCE(!bpf_prog_ebpf_jited(prog)); |
568 | ||
535911c8 | 569 | prog->aux->ksym.start = (unsigned long) prog->bpf_func; |
d00c6473 | 570 | prog->aux->ksym.end = prog->aux->ksym.start + prog->jited_len; |
74451e66 DB |
571 | } |
572 | ||
bfea9a85 JO |
573 | static void |
574 | bpf_prog_ksym_set_name(struct bpf_prog *prog) | |
74451e66 | 575 | { |
bfea9a85 | 576 | char *sym = prog->aux->ksym.name; |
368211fb | 577 | const char *end = sym + KSYM_NAME_LEN; |
838e9690 YS |
578 | const struct btf_type *type; |
579 | const char *func_name; | |
368211fb | 580 | |
74451e66 | 581 | BUILD_BUG_ON(sizeof("bpf_prog_") + |
368211fb MKL |
582 | sizeof(prog->tag) * 2 + |
583 | /* name has been null terminated. | |
584 | * We should need +1 for the '_' preceding | |
585 | * the name. However, the null character | |
586 | * is double counted between the name and the | |
587 | * sizeof("bpf_prog_") above, so we omit | |
588 | * the +1 here. | |
589 | */ | |
590 | sizeof(prog->aux->name) > KSYM_NAME_LEN); | |
74451e66 DB |
591 | |
592 | sym += snprintf(sym, KSYM_NAME_LEN, "bpf_prog_"); | |
593 | sym = bin2hex(sym, prog->tag, sizeof(prog->tag)); | |
838e9690 YS |
594 | |
595 | /* prog->aux->name will be ignored if full btf name is available */ | |
335d1c5b | 596 | if (prog->aux->func_info_cnt && prog->aux->func_idx < prog->aux->func_info_cnt) { |
ba64e7d8 YS |
597 | type = btf_type_by_id(prog->aux->btf, |
598 | prog->aux->func_info[prog->aux->func_idx].type_id); | |
838e9690 YS |
599 | func_name = btf_name_by_offset(prog->aux->btf, type->name_off); |
600 | snprintf(sym, (size_t)(end - sym), "_%s", func_name); | |
601 | return; | |
602 | } | |
603 | ||
368211fb MKL |
604 | if (prog->aux->name[0]) |
605 | snprintf(sym, (size_t)(end - sym), "_%s", prog->aux->name); | |
606 | else | |
607 | *sym = 0; | |
74451e66 DB |
608 | } |
609 | ||
ca4424c9 | 610 | static unsigned long bpf_get_ksym_start(struct latch_tree_node *n) |
74451e66 | 611 | { |
ca4424c9 | 612 | return container_of(n, struct bpf_ksym, tnode)->start; |
74451e66 DB |
613 | } |
614 | ||
615 | static __always_inline bool bpf_tree_less(struct latch_tree_node *a, | |
616 | struct latch_tree_node *b) | |
617 | { | |
ca4424c9 | 618 | return bpf_get_ksym_start(a) < bpf_get_ksym_start(b); |
74451e66 DB |
619 | } |
620 | ||
621 | static __always_inline int bpf_tree_comp(void *key, struct latch_tree_node *n) | |
622 | { | |
623 | unsigned long val = (unsigned long)key; | |
ca4424c9 | 624 | const struct bpf_ksym *ksym; |
74451e66 | 625 | |
ca4424c9 | 626 | ksym = container_of(n, struct bpf_ksym, tnode); |
74451e66 | 627 | |
ca4424c9 | 628 | if (val < ksym->start) |
74451e66 | 629 | return -1; |
66d9111f KKD |
630 | /* Ensure that we detect return addresses as part of the program, when |
631 | * the final instruction is a call for a program part of the stack | |
632 | * trace. Therefore, do val > ksym->end instead of val >= ksym->end. | |
633 | */ | |
634 | if (val > ksym->end) | |
74451e66 DB |
635 | return 1; |
636 | ||
637 | return 0; | |
638 | } | |
639 | ||
640 | static const struct latch_tree_ops bpf_tree_ops = { | |
641 | .less = bpf_tree_less, | |
642 | .comp = bpf_tree_comp, | |
643 | }; | |
644 | ||
645 | static DEFINE_SPINLOCK(bpf_lock); | |
646 | static LIST_HEAD(bpf_kallsyms); | |
647 | static struct latch_tree_root bpf_tree __cacheline_aligned; | |
648 | ||
dba122fb | 649 | void bpf_ksym_add(struct bpf_ksym *ksym) |
74451e66 | 650 | { |
dba122fb JO |
651 | spin_lock_bh(&bpf_lock); |
652 | WARN_ON_ONCE(!list_empty(&ksym->lnode)); | |
653 | list_add_tail_rcu(&ksym->lnode, &bpf_kallsyms); | |
654 | latch_tree_insert(&ksym->tnode, &bpf_tree, &bpf_tree_ops); | |
655 | spin_unlock_bh(&bpf_lock); | |
74451e66 DB |
656 | } |
657 | ||
dba122fb | 658 | static void __bpf_ksym_del(struct bpf_ksym *ksym) |
74451e66 | 659 | { |
dba122fb | 660 | if (list_empty(&ksym->lnode)) |
74451e66 DB |
661 | return; |
662 | ||
dba122fb JO |
663 | latch_tree_erase(&ksym->tnode, &bpf_tree, &bpf_tree_ops); |
664 | list_del_rcu(&ksym->lnode); | |
665 | } | |
666 | ||
667 | void bpf_ksym_del(struct bpf_ksym *ksym) | |
668 | { | |
669 | spin_lock_bh(&bpf_lock); | |
670 | __bpf_ksym_del(ksym); | |
671 | spin_unlock_bh(&bpf_lock); | |
74451e66 DB |
672 | } |
673 | ||
674 | static bool bpf_prog_kallsyms_candidate(const struct bpf_prog *fp) | |
675 | { | |
676 | return fp->jited && !bpf_prog_was_classic(fp); | |
677 | } | |
678 | ||
74451e66 DB |
679 | void bpf_prog_kallsyms_add(struct bpf_prog *fp) |
680 | { | |
74451e66 | 681 | if (!bpf_prog_kallsyms_candidate(fp) || |
2c78ee89 | 682 | !bpf_capable()) |
74451e66 DB |
683 | return; |
684 | ||
535911c8 | 685 | bpf_prog_ksym_set_addr(fp); |
bfea9a85 | 686 | bpf_prog_ksym_set_name(fp); |
cbd76f8d | 687 | fp->aux->ksym.prog = true; |
535911c8 | 688 | |
dba122fb | 689 | bpf_ksym_add(&fp->aux->ksym); |
74451e66 DB |
690 | } |
691 | ||
692 | void bpf_prog_kallsyms_del(struct bpf_prog *fp) | |
693 | { | |
74451e66 DB |
694 | if (!bpf_prog_kallsyms_candidate(fp)) |
695 | return; | |
696 | ||
dba122fb | 697 | bpf_ksym_del(&fp->aux->ksym); |
74451e66 DB |
698 | } |
699 | ||
eda0c929 JO |
700 | static struct bpf_ksym *bpf_ksym_find(unsigned long addr) |
701 | { | |
702 | struct latch_tree_node *n; | |
703 | ||
704 | n = latch_tree_find((void *)addr, &bpf_tree, &bpf_tree_ops); | |
705 | return n ? container_of(n, struct bpf_ksym, tnode) : NULL; | |
706 | } | |
707 | ||
74451e66 DB |
708 | const char *__bpf_address_lookup(unsigned long addr, unsigned long *size, |
709 | unsigned long *off, char *sym) | |
710 | { | |
eda0c929 | 711 | struct bpf_ksym *ksym; |
74451e66 DB |
712 | char *ret = NULL; |
713 | ||
714 | rcu_read_lock(); | |
eda0c929 JO |
715 | ksym = bpf_ksym_find(addr); |
716 | if (ksym) { | |
717 | unsigned long symbol_start = ksym->start; | |
718 | unsigned long symbol_end = ksym->end; | |
535911c8 | 719 | |
eda0c929 | 720 | strncpy(sym, ksym->name, KSYM_NAME_LEN); |
74451e66 DB |
721 | |
722 | ret = sym; | |
723 | if (size) | |
724 | *size = symbol_end - symbol_start; | |
725 | if (off) | |
726 | *off = addr - symbol_start; | |
727 | } | |
728 | rcu_read_unlock(); | |
729 | ||
730 | return ret; | |
731 | } | |
732 | ||
733 | bool is_bpf_text_address(unsigned long addr) | |
734 | { | |
735 | bool ret; | |
736 | ||
737 | rcu_read_lock(); | |
eda0c929 | 738 | ret = bpf_ksym_find(addr) != NULL; |
74451e66 DB |
739 | rcu_read_unlock(); |
740 | ||
741 | return ret; | |
742 | } | |
743 | ||
f18b03fa | 744 | struct bpf_prog *bpf_prog_ksym_find(unsigned long addr) |
cbd76f8d JO |
745 | { |
746 | struct bpf_ksym *ksym = bpf_ksym_find(addr); | |
747 | ||
748 | return ksym && ksym->prog ? | |
749 | container_of(ksym, struct bpf_prog_aux, ksym)->prog : | |
750 | NULL; | |
751 | } | |
752 | ||
3dec541b AS |
753 | const struct exception_table_entry *search_bpf_extables(unsigned long addr) |
754 | { | |
755 | const struct exception_table_entry *e = NULL; | |
756 | struct bpf_prog *prog; | |
757 | ||
758 | rcu_read_lock(); | |
cbd76f8d | 759 | prog = bpf_prog_ksym_find(addr); |
3dec541b AS |
760 | if (!prog) |
761 | goto out; | |
762 | if (!prog->aux->num_exentries) | |
763 | goto out; | |
764 | ||
765 | e = search_extable(prog->aux->extable, prog->aux->num_exentries, addr); | |
766 | out: | |
767 | rcu_read_unlock(); | |
768 | return e; | |
769 | } | |
770 | ||
74451e66 DB |
771 | int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type, |
772 | char *sym) | |
773 | { | |
ecb60d1c | 774 | struct bpf_ksym *ksym; |
74451e66 DB |
775 | unsigned int it = 0; |
776 | int ret = -ERANGE; | |
777 | ||
778 | if (!bpf_jit_kallsyms_enabled()) | |
779 | return ret; | |
780 | ||
781 | rcu_read_lock(); | |
ecb60d1c | 782 | list_for_each_entry_rcu(ksym, &bpf_kallsyms, lnode) { |
74451e66 DB |
783 | if (it++ != symnum) |
784 | continue; | |
785 | ||
ecb60d1c | 786 | strncpy(sym, ksym->name, KSYM_NAME_LEN); |
74451e66 | 787 | |
ecb60d1c | 788 | *value = ksym->start; |
74451e66 DB |
789 | *type = BPF_SYM_ELF_TYPE; |
790 | ||
791 | ret = 0; | |
792 | break; | |
793 | } | |
794 | rcu_read_unlock(); | |
795 | ||
796 | return ret; | |
797 | } | |
798 | ||
a66886fe DB |
799 | int bpf_jit_add_poke_descriptor(struct bpf_prog *prog, |
800 | struct bpf_jit_poke_descriptor *poke) | |
801 | { | |
802 | struct bpf_jit_poke_descriptor *tab = prog->aux->poke_tab; | |
803 | static const u32 poke_tab_max = 1024; | |
804 | u32 slot = prog->aux->size_poke_tab; | |
805 | u32 size = slot + 1; | |
806 | ||
807 | if (size > poke_tab_max) | |
808 | return -ENOSPC; | |
cf71b174 | 809 | if (poke->tailcall_target || poke->tailcall_target_stable || |
ebf7d1f5 | 810 | poke->tailcall_bypass || poke->adj_off || poke->bypass_addr) |
a66886fe DB |
811 | return -EINVAL; |
812 | ||
813 | switch (poke->reason) { | |
814 | case BPF_POKE_REASON_TAIL_CALL: | |
815 | if (!poke->tail_call.map) | |
816 | return -EINVAL; | |
817 | break; | |
818 | default: | |
819 | return -EINVAL; | |
820 | } | |
821 | ||
822 | tab = krealloc(tab, size * sizeof(*poke), GFP_KERNEL); | |
823 | if (!tab) | |
824 | return -ENOMEM; | |
825 | ||
826 | memcpy(&tab[slot], poke, sizeof(*poke)); | |
827 | prog->aux->size_poke_tab = size; | |
828 | prog->aux->poke_tab = tab; | |
829 | ||
830 | return slot; | |
831 | } | |
832 | ||
57631054 SL |
833 | /* |
834 | * BPF program pack allocator. | |
835 | * | |
836 | * Most BPF programs are pretty small. Allocating a hole page for each | |
837 | * program is sometime a waste. Many small bpf program also adds pressure | |
838 | * to instruction TLB. To solve this issue, we introduce a BPF program pack | |
839 | * allocator. The prog_pack allocator uses HPAGE_PMD_SIZE page (2MB on x86) | |
840 | * to host BPF programs. | |
841 | */ | |
57631054 SL |
842 | #define BPF_PROG_CHUNK_SHIFT 6 |
843 | #define BPF_PROG_CHUNK_SIZE (1 << BPF_PROG_CHUNK_SHIFT) | |
844 | #define BPF_PROG_CHUNK_MASK (~(BPF_PROG_CHUNK_SIZE - 1)) | |
57631054 SL |
845 | |
846 | struct bpf_prog_pack { | |
847 | struct list_head list; | |
848 | void *ptr; | |
4cc0991a | 849 | unsigned long bitmap[]; |
57631054 SL |
850 | }; |
851 | ||
19c02415 SL |
852 | void bpf_jit_fill_hole_with_zero(void *area, unsigned int size) |
853 | { | |
854 | memset(area, 0, size); | |
855 | } | |
856 | ||
57631054 SL |
857 | #define BPF_PROG_SIZE_TO_NBITS(size) (round_up(size, BPF_PROG_CHUNK_SIZE) / BPF_PROG_CHUNK_SIZE) |
858 | ||
859 | static DEFINE_MUTEX(pack_mutex); | |
860 | static LIST_HEAD(pack_list); | |
861 | ||
e5810941 SL |
862 | /* PMD_SIZE is not available in some special config, e.g. ARCH=arm with |
863 | * CONFIG_MMU=n. Use PAGE_SIZE in these cases. | |
864 | */ | |
865 | #ifdef PMD_SIZE | |
ea2babac | 866 | #define BPF_PROG_PACK_SIZE (PMD_SIZE * num_possible_nodes()) |
e5810941 | 867 | #else |
ea2babac | 868 | #define BPF_PROG_PACK_SIZE PAGE_SIZE |
e5810941 SL |
869 | #endif |
870 | ||
ea2babac | 871 | #define BPF_PROG_CHUNK_COUNT (BPF_PROG_PACK_SIZE / BPF_PROG_CHUNK_SIZE) |
ef078600 | 872 | |
d88bb5ee | 873 | static struct bpf_prog_pack *alloc_new_pack(bpf_jit_fill_hole_t bpf_fill_ill_insns) |
57631054 SL |
874 | { |
875 | struct bpf_prog_pack *pack; | |
876 | ||
ea2babac | 877 | pack = kzalloc(struct_size(pack, bitmap, BITS_TO_LONGS(BPF_PROG_CHUNK_COUNT)), |
ef078600 | 878 | GFP_KERNEL); |
57631054 SL |
879 | if (!pack) |
880 | return NULL; | |
20e490ad | 881 | pack->ptr = bpf_jit_alloc_exec(BPF_PROG_PACK_SIZE); |
57631054 SL |
882 | if (!pack->ptr) { |
883 | kfree(pack); | |
884 | return NULL; | |
885 | } | |
ea2babac SL |
886 | bpf_fill_ill_insns(pack->ptr, BPF_PROG_PACK_SIZE); |
887 | bitmap_zero(pack->bitmap, BPF_PROG_PACK_SIZE / BPF_PROG_CHUNK_SIZE); | |
57631054 SL |
888 | list_add_tail(&pack->list, &pack_list); |
889 | ||
890 | set_vm_flush_reset_perms(pack->ptr); | |
d48567c9 | 891 | set_memory_rox((unsigned long)pack->ptr, BPF_PROG_PACK_SIZE / PAGE_SIZE); |
57631054 SL |
892 | return pack; |
893 | } | |
894 | ||
19c02415 | 895 | void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns) |
57631054 SL |
896 | { |
897 | unsigned int nbits = BPF_PROG_SIZE_TO_NBITS(size); | |
898 | struct bpf_prog_pack *pack; | |
899 | unsigned long pos; | |
900 | void *ptr = NULL; | |
901 | ||
ef078600 | 902 | mutex_lock(&pack_mutex); |
ea2babac | 903 | if (size > BPF_PROG_PACK_SIZE) { |
57631054 | 904 | size = round_up(size, PAGE_SIZE); |
20e490ad | 905 | ptr = bpf_jit_alloc_exec(size); |
57631054 | 906 | if (ptr) { |
d88bb5ee | 907 | bpf_fill_ill_insns(ptr, size); |
57631054 | 908 | set_vm_flush_reset_perms(ptr); |
d48567c9 | 909 | set_memory_rox((unsigned long)ptr, size / PAGE_SIZE); |
57631054 | 910 | } |
ef078600 | 911 | goto out; |
57631054 | 912 | } |
57631054 | 913 | list_for_each_entry(pack, &pack_list, list) { |
ea2babac | 914 | pos = bitmap_find_next_zero_area(pack->bitmap, BPF_PROG_CHUNK_COUNT, 0, |
57631054 | 915 | nbits, 0); |
ea2babac | 916 | if (pos < BPF_PROG_CHUNK_COUNT) |
57631054 SL |
917 | goto found_free_area; |
918 | } | |
919 | ||
d88bb5ee | 920 | pack = alloc_new_pack(bpf_fill_ill_insns); |
57631054 SL |
921 | if (!pack) |
922 | goto out; | |
923 | ||
924 | pos = 0; | |
925 | ||
926 | found_free_area: | |
927 | bitmap_set(pack->bitmap, pos, nbits); | |
928 | ptr = (void *)(pack->ptr) + (pos << BPF_PROG_CHUNK_SHIFT); | |
929 | ||
930 | out: | |
931 | mutex_unlock(&pack_mutex); | |
932 | return ptr; | |
933 | } | |
934 | ||
19c02415 | 935 | void bpf_prog_pack_free(struct bpf_binary_header *hdr) |
57631054 SL |
936 | { |
937 | struct bpf_prog_pack *pack = NULL, *tmp; | |
938 | unsigned int nbits; | |
939 | unsigned long pos; | |
57631054 | 940 | |
ef078600 | 941 | mutex_lock(&pack_mutex); |
ea2babac | 942 | if (hdr->size > BPF_PROG_PACK_SIZE) { |
20e490ad | 943 | bpf_jit_free_exec(hdr); |
ef078600 | 944 | goto out; |
57631054 SL |
945 | } |
946 | ||
57631054 | 947 | list_for_each_entry(tmp, &pack_list, list) { |
ea2babac | 948 | if ((void *)hdr >= tmp->ptr && (tmp->ptr + BPF_PROG_PACK_SIZE) > (void *)hdr) { |
57631054 SL |
949 | pack = tmp; |
950 | break; | |
951 | } | |
952 | } | |
953 | ||
954 | if (WARN_ONCE(!pack, "bpf_prog_pack bug\n")) | |
955 | goto out; | |
956 | ||
957 | nbits = BPF_PROG_SIZE_TO_NBITS(hdr->size); | |
ea2babac | 958 | pos = ((unsigned long)hdr - (unsigned long)pack->ptr) >> BPF_PROG_CHUNK_SHIFT; |
57631054 | 959 | |
fe736565 SL |
960 | WARN_ONCE(bpf_arch_text_invalidate(hdr, hdr->size), |
961 | "bpf_prog_pack bug: missing bpf_arch_text_invalidate?\n"); | |
962 | ||
57631054 | 963 | bitmap_clear(pack->bitmap, pos, nbits); |
ea2babac SL |
964 | if (bitmap_find_next_zero_area(pack->bitmap, BPF_PROG_CHUNK_COUNT, 0, |
965 | BPF_PROG_CHUNK_COUNT, 0) == 0) { | |
57631054 | 966 | list_del(&pack->list); |
20e490ad | 967 | bpf_jit_free_exec(pack->ptr); |
57631054 SL |
968 | kfree(pack); |
969 | } | |
970 | out: | |
971 | mutex_unlock(&pack_mutex); | |
972 | } | |
973 | ||
ede95a63 DB |
974 | static atomic_long_t bpf_jit_current; |
975 | ||
fdadd049 DB |
976 | /* Can be overridden by an arch's JIT compiler if it has a custom, |
977 | * dedicated BPF backend memory area, or if neither of the two | |
978 | * below apply. | |
979 | */ | |
980 | u64 __weak bpf_jit_alloc_exec_limit(void) | |
981 | { | |
ede95a63 | 982 | #if defined(MODULES_VADDR) |
fdadd049 DB |
983 | return MODULES_END - MODULES_VADDR; |
984 | #else | |
985 | return VMALLOC_END - VMALLOC_START; | |
986 | #endif | |
987 | } | |
988 | ||
ede95a63 DB |
989 | static int __init bpf_jit_charge_init(void) |
990 | { | |
991 | /* Only used as heuristic here to derive limit. */ | |
fadb7ff1 | 992 | bpf_jit_limit_max = bpf_jit_alloc_exec_limit(); |
10ec8ca8 | 993 | bpf_jit_limit = min_t(u64, round_up(bpf_jit_limit_max >> 1, |
fdadd049 | 994 | PAGE_SIZE), LONG_MAX); |
ede95a63 DB |
995 | return 0; |
996 | } | |
997 | pure_initcall(bpf_jit_charge_init); | |
ede95a63 | 998 | |
3486bedd | 999 | int bpf_jit_charge_modmem(u32 size) |
ede95a63 | 1000 | { |
0947ae11 | 1001 | if (atomic_long_add_return(size, &bpf_jit_current) > READ_ONCE(bpf_jit_limit)) { |
8a98ae12 | 1002 | if (!bpf_capable()) { |
3486bedd | 1003 | atomic_long_sub(size, &bpf_jit_current); |
ede95a63 DB |
1004 | return -EPERM; |
1005 | } | |
1006 | } | |
1007 | ||
1008 | return 0; | |
1009 | } | |
1010 | ||
3486bedd | 1011 | void bpf_jit_uncharge_modmem(u32 size) |
ede95a63 | 1012 | { |
3486bedd | 1013 | atomic_long_sub(size, &bpf_jit_current); |
ede95a63 DB |
1014 | } |
1015 | ||
dc002bb6 AB |
1016 | void *__weak bpf_jit_alloc_exec(unsigned long size) |
1017 | { | |
1018 | return module_alloc(size); | |
1019 | } | |
1020 | ||
1021 | void __weak bpf_jit_free_exec(void *addr) | |
1022 | { | |
1023 | module_memfree(addr); | |
1024 | } | |
1025 | ||
738cbe72 DB |
1026 | struct bpf_binary_header * |
1027 | bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, | |
1028 | unsigned int alignment, | |
1029 | bpf_jit_fill_hole_t bpf_fill_ill_insns) | |
1030 | { | |
1031 | struct bpf_binary_header *hdr; | |
ed2d9e1a | 1032 | u32 size, hole, start; |
738cbe72 | 1033 | |
b7b3fc8d IL |
1034 | WARN_ON_ONCE(!is_power_of_2(alignment) || |
1035 | alignment > BPF_IMAGE_ALIGNMENT); | |
1036 | ||
738cbe72 DB |
1037 | /* Most of BPF filters are really small, but if some of them |
1038 | * fill a page, allow at least 128 extra bytes to insert a | |
1039 | * random section of illegal instructions. | |
1040 | */ | |
1041 | size = round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE); | |
ede95a63 | 1042 | |
3486bedd | 1043 | if (bpf_jit_charge_modmem(size)) |
ede95a63 | 1044 | return NULL; |
dc002bb6 | 1045 | hdr = bpf_jit_alloc_exec(size); |
ede95a63 | 1046 | if (!hdr) { |
3486bedd | 1047 | bpf_jit_uncharge_modmem(size); |
738cbe72 | 1048 | return NULL; |
ede95a63 | 1049 | } |
738cbe72 DB |
1050 | |
1051 | /* Fill space with illegal/arch-dep instructions. */ | |
1052 | bpf_fill_ill_insns(hdr, size); | |
1053 | ||
ed2d9e1a | 1054 | hdr->size = size; |
738cbe72 DB |
1055 | hole = min_t(unsigned int, size - (proglen + sizeof(*hdr)), |
1056 | PAGE_SIZE - sizeof(*hdr)); | |
8032bf12 | 1057 | start = get_random_u32_below(hole) & ~(alignment - 1); |
738cbe72 DB |
1058 | |
1059 | /* Leave a random number of instructions before BPF code. */ | |
1060 | *image_ptr = &hdr->image[start]; | |
1061 | ||
1062 | return hdr; | |
1063 | } | |
1064 | ||
1065 | void bpf_jit_binary_free(struct bpf_binary_header *hdr) | |
1066 | { | |
ed2d9e1a | 1067 | u32 size = hdr->size; |
ede95a63 | 1068 | |
dc002bb6 | 1069 | bpf_jit_free_exec(hdr); |
ed2d9e1a | 1070 | bpf_jit_uncharge_modmem(size); |
738cbe72 | 1071 | } |
4f3446bb | 1072 | |
33c98058 SL |
1073 | /* Allocate jit binary from bpf_prog_pack allocator. |
1074 | * Since the allocated memory is RO+X, the JIT engine cannot write directly | |
1075 | * to the memory. To solve this problem, a RW buffer is also allocated at | |
1076 | * as the same time. The JIT engine should calculate offsets based on the | |
1077 | * RO memory address, but write JITed program to the RW buffer. Once the | |
1078 | * JIT engine finishes, it calls bpf_jit_binary_pack_finalize, which copies | |
1079 | * the JITed program to the RO memory. | |
1080 | */ | |
1081 | struct bpf_binary_header * | |
1082 | bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **image_ptr, | |
1083 | unsigned int alignment, | |
1084 | struct bpf_binary_header **rw_header, | |
1085 | u8 **rw_image, | |
1086 | bpf_jit_fill_hole_t bpf_fill_ill_insns) | |
1087 | { | |
1088 | struct bpf_binary_header *ro_header; | |
1089 | u32 size, hole, start; | |
1090 | ||
1091 | WARN_ON_ONCE(!is_power_of_2(alignment) || | |
1092 | alignment > BPF_IMAGE_ALIGNMENT); | |
1093 | ||
1094 | /* add 16 bytes for a random section of illegal instructions */ | |
1095 | size = round_up(proglen + sizeof(*ro_header) + 16, BPF_PROG_CHUNK_SIZE); | |
1096 | ||
1097 | if (bpf_jit_charge_modmem(size)) | |
1098 | return NULL; | |
d88bb5ee | 1099 | ro_header = bpf_prog_pack_alloc(size, bpf_fill_ill_insns); |
33c98058 SL |
1100 | if (!ro_header) { |
1101 | bpf_jit_uncharge_modmem(size); | |
1102 | return NULL; | |
1103 | } | |
1104 | ||
1105 | *rw_header = kvmalloc(size, GFP_KERNEL); | |
1106 | if (!*rw_header) { | |
d24d2a2b | 1107 | bpf_arch_text_copy(&ro_header->size, &size, sizeof(size)); |
33c98058 SL |
1108 | bpf_prog_pack_free(ro_header); |
1109 | bpf_jit_uncharge_modmem(size); | |
1110 | return NULL; | |
1111 | } | |
1112 | ||
1113 | /* Fill space with illegal/arch-dep instructions. */ | |
1114 | bpf_fill_ill_insns(*rw_header, size); | |
1115 | (*rw_header)->size = size; | |
1116 | ||
1117 | hole = min_t(unsigned int, size - (proglen + sizeof(*ro_header)), | |
1118 | BPF_PROG_CHUNK_SIZE - sizeof(*ro_header)); | |
8032bf12 | 1119 | start = get_random_u32_below(hole) & ~(alignment - 1); |
33c98058 SL |
1120 | |
1121 | *image_ptr = &ro_header->image[start]; | |
1122 | *rw_image = &(*rw_header)->image[start]; | |
1123 | ||
1124 | return ro_header; | |
1125 | } | |
1126 | ||
1127 | /* Copy JITed text from rw_header to its final location, the ro_header. */ | |
1128 | int bpf_jit_binary_pack_finalize(struct bpf_prog *prog, | |
1129 | struct bpf_binary_header *ro_header, | |
1130 | struct bpf_binary_header *rw_header) | |
1131 | { | |
1132 | void *ptr; | |
1133 | ||
1134 | ptr = bpf_arch_text_copy(ro_header, rw_header, rw_header->size); | |
1135 | ||
1136 | kvfree(rw_header); | |
1137 | ||
1138 | if (IS_ERR(ptr)) { | |
1139 | bpf_prog_pack_free(ro_header); | |
1140 | return PTR_ERR(ptr); | |
1141 | } | |
33c98058 SL |
1142 | return 0; |
1143 | } | |
1144 | ||
1145 | /* bpf_jit_binary_pack_free is called in two different scenarios: | |
1146 | * 1) when the program is freed after; | |
1147 | * 2) when the JIT engine fails (before bpf_jit_binary_pack_finalize). | |
1148 | * For case 2), we need to free both the RO memory and the RW buffer. | |
676b2daa SL |
1149 | * |
1150 | * bpf_jit_binary_pack_free requires proper ro_header->size. However, | |
1151 | * bpf_jit_binary_pack_alloc does not set it. Therefore, ro_header->size | |
1152 | * must be set with either bpf_jit_binary_pack_finalize (normal path) or | |
1153 | * bpf_arch_text_copy (when jit fails). | |
33c98058 SL |
1154 | */ |
1155 | void bpf_jit_binary_pack_free(struct bpf_binary_header *ro_header, | |
1156 | struct bpf_binary_header *rw_header) | |
1157 | { | |
676b2daa | 1158 | u32 size = ro_header->size; |
33c98058 SL |
1159 | |
1160 | bpf_prog_pack_free(ro_header); | |
1161 | kvfree(rw_header); | |
1162 | bpf_jit_uncharge_modmem(size); | |
1163 | } | |
1164 | ||
1d5f82d9 SL |
1165 | struct bpf_binary_header * |
1166 | bpf_jit_binary_pack_hdr(const struct bpf_prog *fp) | |
1167 | { | |
1168 | unsigned long real_start = (unsigned long)fp->bpf_func; | |
1169 | unsigned long addr; | |
1170 | ||
1171 | addr = real_start & BPF_PROG_CHUNK_MASK; | |
1172 | return (void *)addr; | |
1173 | } | |
1174 | ||
33c98058 SL |
1175 | static inline struct bpf_binary_header * |
1176 | bpf_jit_binary_hdr(const struct bpf_prog *fp) | |
1177 | { | |
1178 | unsigned long real_start = (unsigned long)fp->bpf_func; | |
1179 | unsigned long addr; | |
1180 | ||
1d5f82d9 | 1181 | addr = real_start & PAGE_MASK; |
33c98058 SL |
1182 | return (void *)addr; |
1183 | } | |
1184 | ||
74451e66 DB |
1185 | /* This symbol is only overridden by archs that have different |
1186 | * requirements than the usual eBPF JITs, f.e. when they only | |
1187 | * implement cBPF JIT, do not set images read-only, etc. | |
1188 | */ | |
1189 | void __weak bpf_jit_free(struct bpf_prog *fp) | |
1190 | { | |
1191 | if (fp->jited) { | |
1192 | struct bpf_binary_header *hdr = bpf_jit_binary_hdr(fp); | |
1193 | ||
1d5f82d9 | 1194 | bpf_jit_binary_free(hdr); |
74451e66 DB |
1195 | WARN_ON_ONCE(!bpf_prog_kallsyms_verify_off(fp)); |
1196 | } | |
1197 | ||
1198 | bpf_prog_unlock_free(fp); | |
1199 | } | |
1200 | ||
e2c95a61 DB |
1201 | int bpf_jit_get_func_addr(const struct bpf_prog *prog, |
1202 | const struct bpf_insn *insn, bool extra_pass, | |
1203 | u64 *func_addr, bool *func_addr_fixed) | |
1204 | { | |
1205 | s16 off = insn->off; | |
1206 | s32 imm = insn->imm; | |
1207 | u8 *addr; | |
1cf3bfc6 | 1208 | int err; |
e2c95a61 DB |
1209 | |
1210 | *func_addr_fixed = insn->src_reg != BPF_PSEUDO_CALL; | |
1211 | if (!*func_addr_fixed) { | |
1212 | /* Place-holder address till the last pass has collected | |
1213 | * all addresses for JITed subprograms in which case we | |
1214 | * can pick them up from prog->aux. | |
1215 | */ | |
1216 | if (!extra_pass) | |
1217 | addr = NULL; | |
1218 | else if (prog->aux->func && | |
335d1c5b | 1219 | off >= 0 && off < prog->aux->real_func_cnt) |
e2c95a61 DB |
1220 | addr = (u8 *)prog->aux->func[off]->bpf_func; |
1221 | else | |
1222 | return -EINVAL; | |
1cf3bfc6 IL |
1223 | } else if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL && |
1224 | bpf_jit_supports_far_kfunc_call()) { | |
1225 | err = bpf_get_kfunc_addr(prog, insn->imm, insn->off, &addr); | |
1226 | if (err) | |
1227 | return err; | |
e2c95a61 DB |
1228 | } else { |
1229 | /* Address of a BPF helper call. Since part of the core | |
1230 | * kernel, it's always at a fixed location. __bpf_call_base | |
1231 | * and the helper with imm relative to it are both in core | |
1232 | * kernel. | |
1233 | */ | |
1234 | addr = (u8 *)__bpf_call_base + imm; | |
1235 | } | |
1236 | ||
1237 | *func_addr = (unsigned long)addr; | |
1238 | return 0; | |
1239 | } | |
1240 | ||
4f3446bb DB |
1241 | static int bpf_jit_blind_insn(const struct bpf_insn *from, |
1242 | const struct bpf_insn *aux, | |
ede7c460 NR |
1243 | struct bpf_insn *to_buff, |
1244 | bool emit_zext) | |
4f3446bb DB |
1245 | { |
1246 | struct bpf_insn *to = to_buff; | |
a251c17a | 1247 | u32 imm_rnd = get_random_u32(); |
4f3446bb DB |
1248 | s16 off; |
1249 | ||
1250 | BUILD_BUG_ON(BPF_REG_AX + 1 != MAX_BPF_JIT_REG); | |
1251 | BUILD_BUG_ON(MAX_BPF_REG + 1 != MAX_BPF_JIT_REG); | |
1252 | ||
9b73bfdd DB |
1253 | /* Constraints on AX register: |
1254 | * | |
1255 | * AX register is inaccessible from user space. It is mapped in | |
1256 | * all JITs, and used here for constant blinding rewrites. It is | |
1257 | * typically "stateless" meaning its contents are only valid within | |
1258 | * the executed instruction, but not across several instructions. | |
1259 | * There are a few exceptions however which are further detailed | |
1260 | * below. | |
1261 | * | |
1262 | * Constant blinding is only used by JITs, not in the interpreter. | |
1263 | * The interpreter uses AX in some occasions as a local temporary | |
1264 | * register e.g. in DIV or MOD instructions. | |
1265 | * | |
1266 | * In restricted circumstances, the verifier can also use the AX | |
1267 | * register for rewrites as long as they do not interfere with | |
1268 | * the above cases! | |
1269 | */ | |
1270 | if (from->dst_reg == BPF_REG_AX || from->src_reg == BPF_REG_AX) | |
1271 | goto out; | |
1272 | ||
4f3446bb DB |
1273 | if (from->imm == 0 && |
1274 | (from->code == (BPF_ALU | BPF_MOV | BPF_K) || | |
1275 | from->code == (BPF_ALU64 | BPF_MOV | BPF_K))) { | |
1276 | *to++ = BPF_ALU64_REG(BPF_XOR, from->dst_reg, from->dst_reg); | |
1277 | goto out; | |
1278 | } | |
1279 | ||
1280 | switch (from->code) { | |
1281 | case BPF_ALU | BPF_ADD | BPF_K: | |
1282 | case BPF_ALU | BPF_SUB | BPF_K: | |
1283 | case BPF_ALU | BPF_AND | BPF_K: | |
1284 | case BPF_ALU | BPF_OR | BPF_K: | |
1285 | case BPF_ALU | BPF_XOR | BPF_K: | |
1286 | case BPF_ALU | BPF_MUL | BPF_K: | |
1287 | case BPF_ALU | BPF_MOV | BPF_K: | |
1288 | case BPF_ALU | BPF_DIV | BPF_K: | |
1289 | case BPF_ALU | BPF_MOD | BPF_K: | |
1290 | *to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); | |
1291 | *to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); | |
7058e3a3 | 1292 | *to++ = BPF_ALU32_REG_OFF(from->code, from->dst_reg, BPF_REG_AX, from->off); |
4f3446bb DB |
1293 | break; |
1294 | ||
1295 | case BPF_ALU64 | BPF_ADD | BPF_K: | |
1296 | case BPF_ALU64 | BPF_SUB | BPF_K: | |
1297 | case BPF_ALU64 | BPF_AND | BPF_K: | |
1298 | case BPF_ALU64 | BPF_OR | BPF_K: | |
1299 | case BPF_ALU64 | BPF_XOR | BPF_K: | |
1300 | case BPF_ALU64 | BPF_MUL | BPF_K: | |
1301 | case BPF_ALU64 | BPF_MOV | BPF_K: | |
1302 | case BPF_ALU64 | BPF_DIV | BPF_K: | |
1303 | case BPF_ALU64 | BPF_MOD | BPF_K: | |
1304 | *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); | |
1305 | *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); | |
7058e3a3 | 1306 | *to++ = BPF_ALU64_REG_OFF(from->code, from->dst_reg, BPF_REG_AX, from->off); |
4f3446bb DB |
1307 | break; |
1308 | ||
1309 | case BPF_JMP | BPF_JEQ | BPF_K: | |
1310 | case BPF_JMP | BPF_JNE | BPF_K: | |
1311 | case BPF_JMP | BPF_JGT | BPF_K: | |
92b31a9a | 1312 | case BPF_JMP | BPF_JLT | BPF_K: |
4f3446bb | 1313 | case BPF_JMP | BPF_JGE | BPF_K: |
92b31a9a | 1314 | case BPF_JMP | BPF_JLE | BPF_K: |
4f3446bb | 1315 | case BPF_JMP | BPF_JSGT | BPF_K: |
92b31a9a | 1316 | case BPF_JMP | BPF_JSLT | BPF_K: |
4f3446bb | 1317 | case BPF_JMP | BPF_JSGE | BPF_K: |
92b31a9a | 1318 | case BPF_JMP | BPF_JSLE | BPF_K: |
4f3446bb DB |
1319 | case BPF_JMP | BPF_JSET | BPF_K: |
1320 | /* Accommodate for extra offset in case of a backjump. */ | |
1321 | off = from->off; | |
1322 | if (off < 0) | |
1323 | off -= 2; | |
1324 | *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); | |
1325 | *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); | |
1326 | *to++ = BPF_JMP_REG(from->code, from->dst_reg, BPF_REG_AX, off); | |
1327 | break; | |
1328 | ||
a7b76c88 JW |
1329 | case BPF_JMP32 | BPF_JEQ | BPF_K: |
1330 | case BPF_JMP32 | BPF_JNE | BPF_K: | |
1331 | case BPF_JMP32 | BPF_JGT | BPF_K: | |
1332 | case BPF_JMP32 | BPF_JLT | BPF_K: | |
1333 | case BPF_JMP32 | BPF_JGE | BPF_K: | |
1334 | case BPF_JMP32 | BPF_JLE | BPF_K: | |
1335 | case BPF_JMP32 | BPF_JSGT | BPF_K: | |
1336 | case BPF_JMP32 | BPF_JSLT | BPF_K: | |
1337 | case BPF_JMP32 | BPF_JSGE | BPF_K: | |
1338 | case BPF_JMP32 | BPF_JSLE | BPF_K: | |
1339 | case BPF_JMP32 | BPF_JSET | BPF_K: | |
1340 | /* Accommodate for extra offset in case of a backjump. */ | |
1341 | off = from->off; | |
1342 | if (off < 0) | |
1343 | off -= 2; | |
1344 | *to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); | |
1345 | *to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); | |
1346 | *to++ = BPF_JMP32_REG(from->code, from->dst_reg, BPF_REG_AX, | |
1347 | off); | |
1348 | break; | |
1349 | ||
4f3446bb DB |
1350 | case BPF_LD | BPF_IMM | BPF_DW: |
1351 | *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[1].imm); | |
1352 | *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); | |
1353 | *to++ = BPF_ALU64_IMM(BPF_LSH, BPF_REG_AX, 32); | |
1354 | *to++ = BPF_ALU64_REG(BPF_MOV, aux[0].dst_reg, BPF_REG_AX); | |
1355 | break; | |
1356 | case 0: /* Part 2 of BPF_LD | BPF_IMM | BPF_DW. */ | |
1357 | *to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[0].imm); | |
1358 | *to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); | |
ede7c460 NR |
1359 | if (emit_zext) |
1360 | *to++ = BPF_ZEXT_REG(BPF_REG_AX); | |
4f3446bb DB |
1361 | *to++ = BPF_ALU64_REG(BPF_OR, aux[0].dst_reg, BPF_REG_AX); |
1362 | break; | |
1363 | ||
1364 | case BPF_ST | BPF_MEM | BPF_DW: | |
1365 | case BPF_ST | BPF_MEM | BPF_W: | |
1366 | case BPF_ST | BPF_MEM | BPF_H: | |
1367 | case BPF_ST | BPF_MEM | BPF_B: | |
1368 | *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); | |
1369 | *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); | |
1370 | *to++ = BPF_STX_MEM(from->code, from->dst_reg, BPF_REG_AX, from->off); | |
1371 | break; | |
1372 | } | |
1373 | out: | |
1374 | return to - to_buff; | |
1375 | } | |
1376 | ||
1377 | static struct bpf_prog *bpf_prog_clone_create(struct bpf_prog *fp_other, | |
1378 | gfp_t gfp_extra_flags) | |
1379 | { | |
19809c2d | 1380 | gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags; |
4f3446bb DB |
1381 | struct bpf_prog *fp; |
1382 | ||
88dca4ca | 1383 | fp = __vmalloc(fp_other->pages * PAGE_SIZE, gfp_flags); |
4f3446bb | 1384 | if (fp != NULL) { |
4f3446bb DB |
1385 | /* aux->prog still points to the fp_other one, so |
1386 | * when promoting the clone to the real program, | |
1387 | * this still needs to be adapted. | |
1388 | */ | |
1389 | memcpy(fp, fp_other, fp_other->pages * PAGE_SIZE); | |
1390 | } | |
1391 | ||
1392 | return fp; | |
1393 | } | |
1394 | ||
1395 | static void bpf_prog_clone_free(struct bpf_prog *fp) | |
1396 | { | |
1397 | /* aux was stolen by the other clone, so we cannot free | |
1398 | * it from this path! It will be freed eventually by the | |
1399 | * other program on release. | |
1400 | * | |
1401 | * At this point, we don't need a deferred release since | |
1402 | * clone is guaranteed to not be locked. | |
1403 | */ | |
1404 | fp->aux = NULL; | |
53f523f3 CW |
1405 | fp->stats = NULL; |
1406 | fp->active = NULL; | |
4f3446bb DB |
1407 | __bpf_prog_free(fp); |
1408 | } | |
1409 | ||
1410 | void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other) | |
1411 | { | |
1412 | /* We have to repoint aux->prog to self, as we don't | |
1413 | * know whether fp here is the clone or the original. | |
1414 | */ | |
1415 | fp->aux->prog = fp; | |
1416 | bpf_prog_clone_free(fp_other); | |
1417 | } | |
1418 | ||
1419 | struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) | |
1420 | { | |
1421 | struct bpf_insn insn_buff[16], aux[2]; | |
1422 | struct bpf_prog *clone, *tmp; | |
1423 | int insn_delta, insn_cnt; | |
1424 | struct bpf_insn *insn; | |
1425 | int i, rewritten; | |
1426 | ||
d2a3b7c5 | 1427 | if (!prog->blinding_requested || prog->blinded) |
4f3446bb DB |
1428 | return prog; |
1429 | ||
1430 | clone = bpf_prog_clone_create(prog, GFP_USER); | |
1431 | if (!clone) | |
1432 | return ERR_PTR(-ENOMEM); | |
1433 | ||
1434 | insn_cnt = clone->len; | |
1435 | insn = clone->insnsi; | |
1436 | ||
1437 | for (i = 0; i < insn_cnt; i++, insn++) { | |
4b6313cf AS |
1438 | if (bpf_pseudo_func(insn)) { |
1439 | /* ld_imm64 with an address of bpf subprog is not | |
1440 | * a user controlled constant. Don't randomize it, | |
1441 | * since it will conflict with jit_subprogs() logic. | |
1442 | */ | |
1443 | insn++; | |
1444 | i++; | |
1445 | continue; | |
1446 | } | |
1447 | ||
4f3446bb DB |
1448 | /* We temporarily need to hold the original ld64 insn |
1449 | * so that we can still access the first part in the | |
1450 | * second blinding run. | |
1451 | */ | |
1452 | if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW) && | |
1453 | insn[1].code == 0) | |
1454 | memcpy(aux, insn, sizeof(aux)); | |
1455 | ||
ede7c460 NR |
1456 | rewritten = bpf_jit_blind_insn(insn, aux, insn_buff, |
1457 | clone->aux->verifier_zext); | |
4f3446bb DB |
1458 | if (!rewritten) |
1459 | continue; | |
1460 | ||
1461 | tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten); | |
4f73379e | 1462 | if (IS_ERR(tmp)) { |
4f3446bb DB |
1463 | /* Patching may have repointed aux->prog during |
1464 | * realloc from the original one, so we need to | |
1465 | * fix it up here on error. | |
1466 | */ | |
1467 | bpf_jit_prog_release_other(prog, clone); | |
4f73379e | 1468 | return tmp; |
4f3446bb DB |
1469 | } |
1470 | ||
1471 | clone = tmp; | |
1472 | insn_delta = rewritten - 1; | |
1473 | ||
1474 | /* Walk new program and skip insns we just inserted. */ | |
1475 | insn = clone->insnsi + i + insn_delta; | |
1476 | insn_cnt += insn_delta; | |
1477 | i += insn_delta; | |
1478 | } | |
1479 | ||
1c2a088a | 1480 | clone->blinded = 1; |
4f3446bb DB |
1481 | return clone; |
1482 | } | |
b954d834 | 1483 | #endif /* CONFIG_BPF_JIT */ |
738cbe72 | 1484 | |
f5bffecd AS |
1485 | /* Base function for offset calculation. Needs to go into .text section, |
1486 | * therefore keeping it non-static as well; will also be used by JITs | |
7105e828 DB |
1487 | * anyway later on, so do not let the compiler omit it. This also needs |
1488 | * to go into kallsyms for correlation from e.g. bpftool, so naming | |
1489 | * must not change. | |
f5bffecd AS |
1490 | */ |
1491 | noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) | |
1492 | { | |
1493 | return 0; | |
1494 | } | |
4d9c5c53 | 1495 | EXPORT_SYMBOL_GPL(__bpf_call_base); |
f5bffecd | 1496 | |
5e581dad DB |
1497 | /* All UAPI available opcodes. */ |
1498 | #define BPF_INSN_MAP(INSN_2, INSN_3) \ | |
1499 | /* 32 bit ALU operations. */ \ | |
1500 | /* Register based. */ \ | |
2dc6b100 JW |
1501 | INSN_3(ALU, ADD, X), \ |
1502 | INSN_3(ALU, SUB, X), \ | |
1503 | INSN_3(ALU, AND, X), \ | |
1504 | INSN_3(ALU, OR, X), \ | |
1505 | INSN_3(ALU, LSH, X), \ | |
1506 | INSN_3(ALU, RSH, X), \ | |
1507 | INSN_3(ALU, XOR, X), \ | |
1508 | INSN_3(ALU, MUL, X), \ | |
1509 | INSN_3(ALU, MOV, X), \ | |
1510 | INSN_3(ALU, ARSH, X), \ | |
1511 | INSN_3(ALU, DIV, X), \ | |
1512 | INSN_3(ALU, MOD, X), \ | |
5e581dad DB |
1513 | INSN_2(ALU, NEG), \ |
1514 | INSN_3(ALU, END, TO_BE), \ | |
1515 | INSN_3(ALU, END, TO_LE), \ | |
1516 | /* Immediate based. */ \ | |
2dc6b100 JW |
1517 | INSN_3(ALU, ADD, K), \ |
1518 | INSN_3(ALU, SUB, K), \ | |
1519 | INSN_3(ALU, AND, K), \ | |
1520 | INSN_3(ALU, OR, K), \ | |
1521 | INSN_3(ALU, LSH, K), \ | |
1522 | INSN_3(ALU, RSH, K), \ | |
1523 | INSN_3(ALU, XOR, K), \ | |
1524 | INSN_3(ALU, MUL, K), \ | |
1525 | INSN_3(ALU, MOV, K), \ | |
1526 | INSN_3(ALU, ARSH, K), \ | |
1527 | INSN_3(ALU, DIV, K), \ | |
1528 | INSN_3(ALU, MOD, K), \ | |
5e581dad DB |
1529 | /* 64 bit ALU operations. */ \ |
1530 | /* Register based. */ \ | |
1531 | INSN_3(ALU64, ADD, X), \ | |
1532 | INSN_3(ALU64, SUB, X), \ | |
1533 | INSN_3(ALU64, AND, X), \ | |
1534 | INSN_3(ALU64, OR, X), \ | |
1535 | INSN_3(ALU64, LSH, X), \ | |
1536 | INSN_3(ALU64, RSH, X), \ | |
1537 | INSN_3(ALU64, XOR, X), \ | |
1538 | INSN_3(ALU64, MUL, X), \ | |
1539 | INSN_3(ALU64, MOV, X), \ | |
1540 | INSN_3(ALU64, ARSH, X), \ | |
1541 | INSN_3(ALU64, DIV, X), \ | |
1542 | INSN_3(ALU64, MOD, X), \ | |
1543 | INSN_2(ALU64, NEG), \ | |
0845c3db | 1544 | INSN_3(ALU64, END, TO_LE), \ |
5e581dad DB |
1545 | /* Immediate based. */ \ |
1546 | INSN_3(ALU64, ADD, K), \ | |
1547 | INSN_3(ALU64, SUB, K), \ | |
1548 | INSN_3(ALU64, AND, K), \ | |
1549 | INSN_3(ALU64, OR, K), \ | |
1550 | INSN_3(ALU64, LSH, K), \ | |
1551 | INSN_3(ALU64, RSH, K), \ | |
1552 | INSN_3(ALU64, XOR, K), \ | |
1553 | INSN_3(ALU64, MUL, K), \ | |
1554 | INSN_3(ALU64, MOV, K), \ | |
1555 | INSN_3(ALU64, ARSH, K), \ | |
1556 | INSN_3(ALU64, DIV, K), \ | |
1557 | INSN_3(ALU64, MOD, K), \ | |
1558 | /* Call instruction. */ \ | |
1559 | INSN_2(JMP, CALL), \ | |
1560 | /* Exit instruction. */ \ | |
1561 | INSN_2(JMP, EXIT), \ | |
503a8865 JW |
1562 | /* 32-bit Jump instructions. */ \ |
1563 | /* Register based. */ \ | |
1564 | INSN_3(JMP32, JEQ, X), \ | |
1565 | INSN_3(JMP32, JNE, X), \ | |
1566 | INSN_3(JMP32, JGT, X), \ | |
1567 | INSN_3(JMP32, JLT, X), \ | |
1568 | INSN_3(JMP32, JGE, X), \ | |
1569 | INSN_3(JMP32, JLE, X), \ | |
1570 | INSN_3(JMP32, JSGT, X), \ | |
1571 | INSN_3(JMP32, JSLT, X), \ | |
1572 | INSN_3(JMP32, JSGE, X), \ | |
1573 | INSN_3(JMP32, JSLE, X), \ | |
1574 | INSN_3(JMP32, JSET, X), \ | |
1575 | /* Immediate based. */ \ | |
1576 | INSN_3(JMP32, JEQ, K), \ | |
1577 | INSN_3(JMP32, JNE, K), \ | |
1578 | INSN_3(JMP32, JGT, K), \ | |
1579 | INSN_3(JMP32, JLT, K), \ | |
1580 | INSN_3(JMP32, JGE, K), \ | |
1581 | INSN_3(JMP32, JLE, K), \ | |
1582 | INSN_3(JMP32, JSGT, K), \ | |
1583 | INSN_3(JMP32, JSLT, K), \ | |
1584 | INSN_3(JMP32, JSGE, K), \ | |
1585 | INSN_3(JMP32, JSLE, K), \ | |
1586 | INSN_3(JMP32, JSET, K), \ | |
5e581dad DB |
1587 | /* Jump instructions. */ \ |
1588 | /* Register based. */ \ | |
1589 | INSN_3(JMP, JEQ, X), \ | |
1590 | INSN_3(JMP, JNE, X), \ | |
1591 | INSN_3(JMP, JGT, X), \ | |
1592 | INSN_3(JMP, JLT, X), \ | |
1593 | INSN_3(JMP, JGE, X), \ | |
1594 | INSN_3(JMP, JLE, X), \ | |
1595 | INSN_3(JMP, JSGT, X), \ | |
1596 | INSN_3(JMP, JSLT, X), \ | |
1597 | INSN_3(JMP, JSGE, X), \ | |
1598 | INSN_3(JMP, JSLE, X), \ | |
1599 | INSN_3(JMP, JSET, X), \ | |
1600 | /* Immediate based. */ \ | |
1601 | INSN_3(JMP, JEQ, K), \ | |
1602 | INSN_3(JMP, JNE, K), \ | |
1603 | INSN_3(JMP, JGT, K), \ | |
1604 | INSN_3(JMP, JLT, K), \ | |
1605 | INSN_3(JMP, JGE, K), \ | |
1606 | INSN_3(JMP, JLE, K), \ | |
1607 | INSN_3(JMP, JSGT, K), \ | |
1608 | INSN_3(JMP, JSLT, K), \ | |
1609 | INSN_3(JMP, JSGE, K), \ | |
1610 | INSN_3(JMP, JSLE, K), \ | |
1611 | INSN_3(JMP, JSET, K), \ | |
1612 | INSN_2(JMP, JA), \ | |
4cd58e9a | 1613 | INSN_2(JMP32, JA), \ |
5e581dad DB |
1614 | /* Store instructions. */ \ |
1615 | /* Register based. */ \ | |
1616 | INSN_3(STX, MEM, B), \ | |
1617 | INSN_3(STX, MEM, H), \ | |
1618 | INSN_3(STX, MEM, W), \ | |
1619 | INSN_3(STX, MEM, DW), \ | |
91c960b0 BJ |
1620 | INSN_3(STX, ATOMIC, W), \ |
1621 | INSN_3(STX, ATOMIC, DW), \ | |
5e581dad DB |
1622 | /* Immediate based. */ \ |
1623 | INSN_3(ST, MEM, B), \ | |
1624 | INSN_3(ST, MEM, H), \ | |
1625 | INSN_3(ST, MEM, W), \ | |
1626 | INSN_3(ST, MEM, DW), \ | |
1627 | /* Load instructions. */ \ | |
1628 | /* Register based. */ \ | |
1629 | INSN_3(LDX, MEM, B), \ | |
1630 | INSN_3(LDX, MEM, H), \ | |
1631 | INSN_3(LDX, MEM, W), \ | |
1632 | INSN_3(LDX, MEM, DW), \ | |
1f9a1ea8 YS |
1633 | INSN_3(LDX, MEMSX, B), \ |
1634 | INSN_3(LDX, MEMSX, H), \ | |
1635 | INSN_3(LDX, MEMSX, W), \ | |
5e581dad | 1636 | /* Immediate based. */ \ |
e0cea7ce | 1637 | INSN_3(LD, IMM, DW) |
5e581dad DB |
1638 | |
1639 | bool bpf_opcode_in_insntable(u8 code) | |
1640 | { | |
1641 | #define BPF_INSN_2_TBL(x, y) [BPF_##x | BPF_##y] = true | |
1642 | #define BPF_INSN_3_TBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = true | |
1643 | static const bool public_insntable[256] = { | |
1644 | [0 ... 255] = false, | |
1645 | /* Now overwrite non-defaults ... */ | |
1646 | BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL), | |
e0cea7ce DB |
1647 | /* UAPI exposed, but rewritten opcodes. cBPF carry-over. */ |
1648 | [BPF_LD | BPF_ABS | BPF_B] = true, | |
1649 | [BPF_LD | BPF_ABS | BPF_H] = true, | |
1650 | [BPF_LD | BPF_ABS | BPF_W] = true, | |
1651 | [BPF_LD | BPF_IND | BPF_B] = true, | |
1652 | [BPF_LD | BPF_IND | BPF_H] = true, | |
1653 | [BPF_LD | BPF_IND | BPF_W] = true, | |
5e581dad DB |
1654 | }; |
1655 | #undef BPF_INSN_3_TBL | |
1656 | #undef BPF_INSN_2_TBL | |
1657 | return public_insntable[code]; | |
1658 | } | |
1659 | ||
290af866 | 1660 | #ifndef CONFIG_BPF_JIT_ALWAYS_ON |
f5bffecd | 1661 | /** |
019d0454 | 1662 | * ___bpf_prog_run - run eBPF program on a given context |
de1da68d | 1663 | * @regs: is the array of MAX_BPF_EXT_REG eBPF pseudo-registers |
7ae457c1 | 1664 | * @insn: is the array of eBPF instructions |
f5bffecd | 1665 | * |
7ae457c1 | 1666 | * Decode and execute eBPF instructions. |
019d0454 RD |
1667 | * |
1668 | * Return: whatever value is in %BPF_R0 at program exit | |
f5bffecd | 1669 | */ |
2ec9898e | 1670 | static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn) |
f5bffecd | 1671 | { |
5e581dad DB |
1672 | #define BPF_INSN_2_LBL(x, y) [BPF_##x | BPF_##y] = &&x##_##y |
1673 | #define BPF_INSN_3_LBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = &&x##_##y##_##z | |
e55a7325 | 1674 | static const void * const jumptable[256] __annotate_jump_table = { |
f5bffecd AS |
1675 | [0 ... 255] = &&default_label, |
1676 | /* Now overwrite non-defaults ... */ | |
5e581dad DB |
1677 | BPF_INSN_MAP(BPF_INSN_2_LBL, BPF_INSN_3_LBL), |
1678 | /* Non-UAPI available opcodes. */ | |
1ea47e01 | 1679 | [BPF_JMP | BPF_CALL_ARGS] = &&JMP_CALL_ARGS, |
71189fa9 | 1680 | [BPF_JMP | BPF_TAIL_CALL] = &&JMP_TAIL_CALL, |
f5e81d11 | 1681 | [BPF_ST | BPF_NOSPEC] = &&ST_NOSPEC, |
2a02759e AS |
1682 | [BPF_LDX | BPF_PROBE_MEM | BPF_B] = &&LDX_PROBE_MEM_B, |
1683 | [BPF_LDX | BPF_PROBE_MEM | BPF_H] = &&LDX_PROBE_MEM_H, | |
1684 | [BPF_LDX | BPF_PROBE_MEM | BPF_W] = &&LDX_PROBE_MEM_W, | |
1685 | [BPF_LDX | BPF_PROBE_MEM | BPF_DW] = &&LDX_PROBE_MEM_DW, | |
1f9a1ea8 YS |
1686 | [BPF_LDX | BPF_PROBE_MEMSX | BPF_B] = &&LDX_PROBE_MEMSX_B, |
1687 | [BPF_LDX | BPF_PROBE_MEMSX | BPF_H] = &&LDX_PROBE_MEMSX_H, | |
1688 | [BPF_LDX | BPF_PROBE_MEMSX | BPF_W] = &&LDX_PROBE_MEMSX_W, | |
f5bffecd | 1689 | }; |
5e581dad DB |
1690 | #undef BPF_INSN_3_LBL |
1691 | #undef BPF_INSN_2_LBL | |
04fd61ab | 1692 | u32 tail_call_cnt = 0; |
f5bffecd AS |
1693 | |
1694 | #define CONT ({ insn++; goto select_insn; }) | |
1695 | #define CONT_JMP ({ insn++; goto select_insn; }) | |
1696 | ||
f5bffecd AS |
1697 | select_insn: |
1698 | goto *jumptable[insn->code]; | |
1699 | ||
28131e9d DB |
1700 | /* Explicitly mask the register-based shift amounts with 63 or 31 |
1701 | * to avoid undefined behavior. Normally this won't affect the | |
1702 | * generated code, for example, in case of native 64 bit archs such | |
1703 | * as x86-64 or arm64, the compiler is optimizing the AND away for | |
1704 | * the interpreter. In case of JITs, each of the JIT backends compiles | |
1705 | * the BPF shift operations to machine instructions which produce | |
1706 | * implementation-defined results in such a case; the resulting | |
1707 | * contents of the register may be arbitrary, but program behaviour | |
1708 | * as a whole remains defined. In other words, in case of JIT backends, | |
1709 | * the AND must /not/ be added to the emitted LSH/RSH/ARSH translation. | |
1710 | */ | |
1711 | /* ALU (shifts) */ | |
1712 | #define SHT(OPCODE, OP) \ | |
1713 | ALU64_##OPCODE##_X: \ | |
1714 | DST = DST OP (SRC & 63); \ | |
1715 | CONT; \ | |
1716 | ALU_##OPCODE##_X: \ | |
1717 | DST = (u32) DST OP ((u32) SRC & 31); \ | |
1718 | CONT; \ | |
1719 | ALU64_##OPCODE##_K: \ | |
1720 | DST = DST OP IMM; \ | |
1721 | CONT; \ | |
1722 | ALU_##OPCODE##_K: \ | |
1723 | DST = (u32) DST OP (u32) IMM; \ | |
1724 | CONT; | |
1725 | /* ALU (rest) */ | |
1726 | #define ALU(OPCODE, OP) \ | |
1727 | ALU64_##OPCODE##_X: \ | |
1728 | DST = DST OP SRC; \ | |
1729 | CONT; \ | |
1730 | ALU_##OPCODE##_X: \ | |
1731 | DST = (u32) DST OP (u32) SRC; \ | |
1732 | CONT; \ | |
1733 | ALU64_##OPCODE##_K: \ | |
1734 | DST = DST OP IMM; \ | |
1735 | CONT; \ | |
1736 | ALU_##OPCODE##_K: \ | |
1737 | DST = (u32) DST OP (u32) IMM; \ | |
f5bffecd | 1738 | CONT; |
f5bffecd AS |
1739 | ALU(ADD, +) |
1740 | ALU(SUB, -) | |
1741 | ALU(AND, &) | |
1742 | ALU(OR, |) | |
f5bffecd AS |
1743 | ALU(XOR, ^) |
1744 | ALU(MUL, *) | |
28131e9d DB |
1745 | SHT(LSH, <<) |
1746 | SHT(RSH, >>) | |
1747 | #undef SHT | |
f5bffecd AS |
1748 | #undef ALU |
1749 | ALU_NEG: | |
1750 | DST = (u32) -DST; | |
1751 | CONT; | |
1752 | ALU64_NEG: | |
1753 | DST = -DST; | |
1754 | CONT; | |
1755 | ALU_MOV_X: | |
8100928c YS |
1756 | switch (OFF) { |
1757 | case 0: | |
1758 | DST = (u32) SRC; | |
1759 | break; | |
1760 | case 8: | |
1761 | DST = (u32)(s8) SRC; | |
1762 | break; | |
1763 | case 16: | |
1764 | DST = (u32)(s16) SRC; | |
1765 | break; | |
1766 | } | |
f5bffecd AS |
1767 | CONT; |
1768 | ALU_MOV_K: | |
1769 | DST = (u32) IMM; | |
1770 | CONT; | |
1771 | ALU64_MOV_X: | |
8100928c YS |
1772 | switch (OFF) { |
1773 | case 0: | |
1774 | DST = SRC; | |
1775 | break; | |
1776 | case 8: | |
1777 | DST = (s8) SRC; | |
1778 | break; | |
1779 | case 16: | |
1780 | DST = (s16) SRC; | |
1781 | break; | |
1782 | case 32: | |
1783 | DST = (s32) SRC; | |
1784 | break; | |
1785 | } | |
f5bffecd AS |
1786 | CONT; |
1787 | ALU64_MOV_K: | |
1788 | DST = IMM; | |
1789 | CONT; | |
02ab695b AS |
1790 | LD_IMM_DW: |
1791 | DST = (u64) (u32) insn[0].imm | ((u64) (u32) insn[1].imm) << 32; | |
1792 | insn++; | |
1793 | CONT; | |
2dc6b100 | 1794 | ALU_ARSH_X: |
28131e9d | 1795 | DST = (u64) (u32) (((s32) DST) >> (SRC & 31)); |
2dc6b100 JW |
1796 | CONT; |
1797 | ALU_ARSH_K: | |
75672dda | 1798 | DST = (u64) (u32) (((s32) DST) >> IMM); |
2dc6b100 | 1799 | CONT; |
f5bffecd | 1800 | ALU64_ARSH_X: |
28131e9d | 1801 | (*(s64 *) &DST) >>= (SRC & 63); |
f5bffecd AS |
1802 | CONT; |
1803 | ALU64_ARSH_K: | |
1804 | (*(s64 *) &DST) >>= IMM; | |
1805 | CONT; | |
1806 | ALU64_MOD_X: | |
ec0e2da9 YS |
1807 | switch (OFF) { |
1808 | case 0: | |
1809 | div64_u64_rem(DST, SRC, &AX); | |
1810 | DST = AX; | |
1811 | break; | |
1812 | case 1: | |
1813 | AX = div64_s64(DST, SRC); | |
1814 | DST = DST - AX * SRC; | |
1815 | break; | |
1816 | } | |
f5bffecd AS |
1817 | CONT; |
1818 | ALU_MOD_X: | |
ec0e2da9 YS |
1819 | switch (OFF) { |
1820 | case 0: | |
1821 | AX = (u32) DST; | |
1822 | DST = do_div(AX, (u32) SRC); | |
1823 | break; | |
1824 | case 1: | |
1825 | AX = abs((s32)DST); | |
1826 | AX = do_div(AX, abs((s32)SRC)); | |
1827 | if ((s32)DST < 0) | |
1828 | DST = (u32)-AX; | |
1829 | else | |
1830 | DST = (u32)AX; | |
1831 | break; | |
1832 | } | |
f5bffecd AS |
1833 | CONT; |
1834 | ALU64_MOD_K: | |
ec0e2da9 YS |
1835 | switch (OFF) { |
1836 | case 0: | |
1837 | div64_u64_rem(DST, IMM, &AX); | |
1838 | DST = AX; | |
1839 | break; | |
1840 | case 1: | |
1841 | AX = div64_s64(DST, IMM); | |
1842 | DST = DST - AX * IMM; | |
1843 | break; | |
1844 | } | |
f5bffecd AS |
1845 | CONT; |
1846 | ALU_MOD_K: | |
ec0e2da9 YS |
1847 | switch (OFF) { |
1848 | case 0: | |
1849 | AX = (u32) DST; | |
1850 | DST = do_div(AX, (u32) IMM); | |
1851 | break; | |
1852 | case 1: | |
1853 | AX = abs((s32)DST); | |
1854 | AX = do_div(AX, abs((s32)IMM)); | |
1855 | if ((s32)DST < 0) | |
1856 | DST = (u32)-AX; | |
1857 | else | |
1858 | DST = (u32)AX; | |
1859 | break; | |
1860 | } | |
f5bffecd AS |
1861 | CONT; |
1862 | ALU64_DIV_X: | |
ec0e2da9 YS |
1863 | switch (OFF) { |
1864 | case 0: | |
1865 | DST = div64_u64(DST, SRC); | |
1866 | break; | |
1867 | case 1: | |
1868 | DST = div64_s64(DST, SRC); | |
1869 | break; | |
1870 | } | |
f5bffecd AS |
1871 | CONT; |
1872 | ALU_DIV_X: | |
ec0e2da9 YS |
1873 | switch (OFF) { |
1874 | case 0: | |
1875 | AX = (u32) DST; | |
1876 | do_div(AX, (u32) SRC); | |
1877 | DST = (u32) AX; | |
1878 | break; | |
1879 | case 1: | |
1880 | AX = abs((s32)DST); | |
1881 | do_div(AX, abs((s32)SRC)); | |
09fedc73 | 1882 | if (((s32)DST < 0) == ((s32)SRC < 0)) |
ec0e2da9 YS |
1883 | DST = (u32)AX; |
1884 | else | |
1885 | DST = (u32)-AX; | |
1886 | break; | |
1887 | } | |
f5bffecd AS |
1888 | CONT; |
1889 | ALU64_DIV_K: | |
ec0e2da9 YS |
1890 | switch (OFF) { |
1891 | case 0: | |
1892 | DST = div64_u64(DST, IMM); | |
1893 | break; | |
1894 | case 1: | |
1895 | DST = div64_s64(DST, IMM); | |
1896 | break; | |
1897 | } | |
f5bffecd AS |
1898 | CONT; |
1899 | ALU_DIV_K: | |
ec0e2da9 YS |
1900 | switch (OFF) { |
1901 | case 0: | |
1902 | AX = (u32) DST; | |
1903 | do_div(AX, (u32) IMM); | |
1904 | DST = (u32) AX; | |
1905 | break; | |
1906 | case 1: | |
1907 | AX = abs((s32)DST); | |
1908 | do_div(AX, abs((s32)IMM)); | |
09fedc73 | 1909 | if (((s32)DST < 0) == ((s32)IMM < 0)) |
ec0e2da9 YS |
1910 | DST = (u32)AX; |
1911 | else | |
1912 | DST = (u32)-AX; | |
1913 | break; | |
1914 | } | |
f5bffecd AS |
1915 | CONT; |
1916 | ALU_END_TO_BE: | |
1917 | switch (IMM) { | |
1918 | case 16: | |
1919 | DST = (__force u16) cpu_to_be16(DST); | |
1920 | break; | |
1921 | case 32: | |
1922 | DST = (__force u32) cpu_to_be32(DST); | |
1923 | break; | |
1924 | case 64: | |
1925 | DST = (__force u64) cpu_to_be64(DST); | |
1926 | break; | |
1927 | } | |
1928 | CONT; | |
1929 | ALU_END_TO_LE: | |
1930 | switch (IMM) { | |
1931 | case 16: | |
1932 | DST = (__force u16) cpu_to_le16(DST); | |
1933 | break; | |
1934 | case 32: | |
1935 | DST = (__force u32) cpu_to_le32(DST); | |
1936 | break; | |
1937 | case 64: | |
1938 | DST = (__force u64) cpu_to_le64(DST); | |
1939 | break; | |
1940 | } | |
1941 | CONT; | |
0845c3db YS |
1942 | ALU64_END_TO_LE: |
1943 | switch (IMM) { | |
1944 | case 16: | |
1945 | DST = (__force u16) __swab16(DST); | |
1946 | break; | |
1947 | case 32: | |
1948 | DST = (__force u32) __swab32(DST); | |
1949 | break; | |
1950 | case 64: | |
1951 | DST = (__force u64) __swab64(DST); | |
1952 | break; | |
1953 | } | |
1954 | CONT; | |
f5bffecd AS |
1955 | |
1956 | /* CALL */ | |
1957 | JMP_CALL: | |
1958 | /* Function call scratches BPF_R1-BPF_R5 registers, | |
1959 | * preserves BPF_R6-BPF_R9, and stores return value | |
1960 | * into BPF_R0. | |
1961 | */ | |
1962 | BPF_R0 = (__bpf_call_base + insn->imm)(BPF_R1, BPF_R2, BPF_R3, | |
1963 | BPF_R4, BPF_R5); | |
1964 | CONT; | |
1965 | ||
1ea47e01 AS |
1966 | JMP_CALL_ARGS: |
1967 | BPF_R0 = (__bpf_call_base_args + insn->imm)(BPF_R1, BPF_R2, | |
1968 | BPF_R3, BPF_R4, | |
1969 | BPF_R5, | |
1970 | insn + insn->off + 1); | |
1971 | CONT; | |
1972 | ||
04fd61ab AS |
1973 | JMP_TAIL_CALL: { |
1974 | struct bpf_map *map = (struct bpf_map *) (unsigned long) BPF_R2; | |
1975 | struct bpf_array *array = container_of(map, struct bpf_array, map); | |
1976 | struct bpf_prog *prog; | |
90caccdd | 1977 | u32 index = BPF_R3; |
04fd61ab AS |
1978 | |
1979 | if (unlikely(index >= array->map.max_entries)) | |
1980 | goto out; | |
ebf7f6f0 TY |
1981 | |
1982 | if (unlikely(tail_call_cnt >= MAX_TAIL_CALL_CNT)) | |
04fd61ab AS |
1983 | goto out; |
1984 | ||
1985 | tail_call_cnt++; | |
1986 | ||
2a36f0b9 | 1987 | prog = READ_ONCE(array->ptrs[index]); |
1ca1cc98 | 1988 | if (!prog) |
04fd61ab AS |
1989 | goto out; |
1990 | ||
c4675f93 DB |
1991 | /* ARG1 at this point is guaranteed to point to CTX from |
1992 | * the verifier side due to the fact that the tail call is | |
0142dddc | 1993 | * handled like a helper, that is, bpf_tail_call_proto, |
c4675f93 DB |
1994 | * where arg1_type is ARG_PTR_TO_CTX. |
1995 | */ | |
04fd61ab AS |
1996 | insn = prog->insnsi; |
1997 | goto select_insn; | |
1998 | out: | |
1999 | CONT; | |
2000 | } | |
f5bffecd AS |
2001 | JMP_JA: |
2002 | insn += insn->off; | |
2003 | CONT; | |
4cd58e9a YS |
2004 | JMP32_JA: |
2005 | insn += insn->imm; | |
2006 | CONT; | |
f5bffecd AS |
2007 | JMP_EXIT: |
2008 | return BPF_R0; | |
503a8865 JW |
2009 | /* JMP */ |
2010 | #define COND_JMP(SIGN, OPCODE, CMP_OP) \ | |
2011 | JMP_##OPCODE##_X: \ | |
2012 | if ((SIGN##64) DST CMP_OP (SIGN##64) SRC) { \ | |
2013 | insn += insn->off; \ | |
2014 | CONT_JMP; \ | |
2015 | } \ | |
2016 | CONT; \ | |
2017 | JMP32_##OPCODE##_X: \ | |
2018 | if ((SIGN##32) DST CMP_OP (SIGN##32) SRC) { \ | |
2019 | insn += insn->off; \ | |
2020 | CONT_JMP; \ | |
2021 | } \ | |
2022 | CONT; \ | |
2023 | JMP_##OPCODE##_K: \ | |
2024 | if ((SIGN##64) DST CMP_OP (SIGN##64) IMM) { \ | |
2025 | insn += insn->off; \ | |
2026 | CONT_JMP; \ | |
2027 | } \ | |
2028 | CONT; \ | |
2029 | JMP32_##OPCODE##_K: \ | |
2030 | if ((SIGN##32) DST CMP_OP (SIGN##32) IMM) { \ | |
2031 | insn += insn->off; \ | |
2032 | CONT_JMP; \ | |
2033 | } \ | |
2034 | CONT; | |
2035 | COND_JMP(u, JEQ, ==) | |
2036 | COND_JMP(u, JNE, !=) | |
2037 | COND_JMP(u, JGT, >) | |
2038 | COND_JMP(u, JLT, <) | |
2039 | COND_JMP(u, JGE, >=) | |
2040 | COND_JMP(u, JLE, <=) | |
2041 | COND_JMP(u, JSET, &) | |
2042 | COND_JMP(s, JSGT, >) | |
2043 | COND_JMP(s, JSLT, <) | |
2044 | COND_JMP(s, JSGE, >=) | |
2045 | COND_JMP(s, JSLE, <=) | |
2046 | #undef COND_JMP | |
f5e81d11 DB |
2047 | /* ST, STX and LDX*/ |
2048 | ST_NOSPEC: | |
2049 | /* Speculation barrier for mitigating Speculative Store Bypass. | |
2050 | * In case of arm64, we rely on the firmware mitigation as | |
2051 | * controlled via the ssbd kernel parameter. Whenever the | |
2052 | * mitigation is enabled, it works for all of the kernel code | |
2053 | * with no need to provide any additional instructions here. | |
2054 | * In case of x86, we use 'lfence' insn for mitigation. We | |
2055 | * reuse preexisting logic from Spectre v1 mitigation that | |
2056 | * happens to produce the required code on x86 for v4 as well. | |
2057 | */ | |
f5e81d11 | 2058 | barrier_nospec(); |
f5e81d11 | 2059 | CONT; |
f5bffecd AS |
2060 | #define LDST(SIZEOP, SIZE) \ |
2061 | STX_MEM_##SIZEOP: \ | |
2062 | *(SIZE *)(unsigned long) (DST + insn->off) = SRC; \ | |
2063 | CONT; \ | |
2064 | ST_MEM_##SIZEOP: \ | |
2065 | *(SIZE *)(unsigned long) (DST + insn->off) = IMM; \ | |
2066 | CONT; \ | |
2067 | LDX_MEM_##SIZEOP: \ | |
2068 | DST = *(SIZE *)(unsigned long) (SRC + insn->off); \ | |
caff1fa4 MD |
2069 | CONT; \ |
2070 | LDX_PROBE_MEM_##SIZEOP: \ | |
6a5a148a AB |
2071 | bpf_probe_read_kernel_common(&DST, sizeof(SIZE), \ |
2072 | (const void *)(long) (SRC + insn->off)); \ | |
caff1fa4 | 2073 | DST = *((SIZE *)&DST); \ |
f5bffecd AS |
2074 | CONT; |
2075 | ||
2076 | LDST(B, u8) | |
2077 | LDST(H, u16) | |
2078 | LDST(W, u32) | |
2079 | LDST(DW, u64) | |
2080 | #undef LDST | |
2a02759e | 2081 | |
1f9a1ea8 YS |
2082 | #define LDSX(SIZEOP, SIZE) \ |
2083 | LDX_MEMSX_##SIZEOP: \ | |
2084 | DST = *(SIZE *)(unsigned long) (SRC + insn->off); \ | |
2085 | CONT; \ | |
2086 | LDX_PROBE_MEMSX_##SIZEOP: \ | |
6a5a148a | 2087 | bpf_probe_read_kernel_common(&DST, sizeof(SIZE), \ |
1f9a1ea8 YS |
2088 | (const void *)(long) (SRC + insn->off)); \ |
2089 | DST = *((SIZE *)&DST); \ | |
2090 | CONT; | |
2091 | ||
2092 | LDSX(B, s8) | |
2093 | LDSX(H, s16) | |
2094 | LDSX(W, s32) | |
2095 | #undef LDSX | |
2096 | ||
46291067 BJ |
2097 | #define ATOMIC_ALU_OP(BOP, KOP) \ |
2098 | case BOP: \ | |
2099 | if (BPF_SIZE(insn->code) == BPF_W) \ | |
2100 | atomic_##KOP((u32) SRC, (atomic_t *)(unsigned long) \ | |
2101 | (DST + insn->off)); \ | |
2102 | else \ | |
2103 | atomic64_##KOP((u64) SRC, (atomic64_t *)(unsigned long) \ | |
2104 | (DST + insn->off)); \ | |
2105 | break; \ | |
2106 | case BOP | BPF_FETCH: \ | |
2107 | if (BPF_SIZE(insn->code) == BPF_W) \ | |
2108 | SRC = (u32) atomic_fetch_##KOP( \ | |
2109 | (u32) SRC, \ | |
2110 | (atomic_t *)(unsigned long) (DST + insn->off)); \ | |
2111 | else \ | |
2112 | SRC = (u64) atomic64_fetch_##KOP( \ | |
2113 | (u64) SRC, \ | |
2114 | (atomic64_t *)(unsigned long) (DST + insn->off)); \ | |
5ffa2550 | 2115 | break; |
5ca419f2 | 2116 | |
91c960b0 | 2117 | STX_ATOMIC_DW: |
46291067 | 2118 | STX_ATOMIC_W: |
91c960b0 | 2119 | switch (IMM) { |
46291067 | 2120 | ATOMIC_ALU_OP(BPF_ADD, add) |
981f94c3 BJ |
2121 | ATOMIC_ALU_OP(BPF_AND, and) |
2122 | ATOMIC_ALU_OP(BPF_OR, or) | |
2123 | ATOMIC_ALU_OP(BPF_XOR, xor) | |
46291067 BJ |
2124 | #undef ATOMIC_ALU_OP |
2125 | ||
5ffa2550 | 2126 | case BPF_XCHG: |
46291067 BJ |
2127 | if (BPF_SIZE(insn->code) == BPF_W) |
2128 | SRC = (u32) atomic_xchg( | |
2129 | (atomic_t *)(unsigned long) (DST + insn->off), | |
2130 | (u32) SRC); | |
2131 | else | |
2132 | SRC = (u64) atomic64_xchg( | |
2133 | (atomic64_t *)(unsigned long) (DST + insn->off), | |
2134 | (u64) SRC); | |
5ffa2550 BJ |
2135 | break; |
2136 | case BPF_CMPXCHG: | |
46291067 BJ |
2137 | if (BPF_SIZE(insn->code) == BPF_W) |
2138 | BPF_R0 = (u32) atomic_cmpxchg( | |
2139 | (atomic_t *)(unsigned long) (DST + insn->off), | |
2140 | (u32) BPF_R0, (u32) SRC); | |
2141 | else | |
2142 | BPF_R0 = (u64) atomic64_cmpxchg( | |
2143 | (atomic64_t *)(unsigned long) (DST + insn->off), | |
2144 | (u64) BPF_R0, (u64) SRC); | |
5ffa2550 | 2145 | break; |
46291067 | 2146 | |
91c960b0 BJ |
2147 | default: |
2148 | goto default_label; | |
2149 | } | |
f5bffecd | 2150 | CONT; |
f5bffecd AS |
2151 | |
2152 | default_label: | |
5e581dad DB |
2153 | /* If we ever reach this, we have a bug somewhere. Die hard here |
2154 | * instead of just returning 0; we could be somewhere in a subprog, | |
2155 | * so execution could continue otherwise which we do /not/ want. | |
2156 | * | |
2157 | * Note, verifier whitelists all opcodes in bpf_opcode_in_insntable(). | |
2158 | */ | |
91c960b0 BJ |
2159 | pr_warn("BPF interpreter: unknown opcode %02x (imm: 0x%x)\n", |
2160 | insn->code, insn->imm); | |
5e581dad | 2161 | BUG_ON(1); |
f5bffecd AS |
2162 | return 0; |
2163 | } | |
f696b8f4 | 2164 | |
b870aa90 AS |
2165 | #define PROG_NAME(stack_size) __bpf_prog_run##stack_size |
2166 | #define DEFINE_BPF_PROG_RUN(stack_size) \ | |
2167 | static unsigned int PROG_NAME(stack_size)(const void *ctx, const struct bpf_insn *insn) \ | |
2168 | { \ | |
2169 | u64 stack[stack_size / sizeof(u64)]; \ | |
a6a7aaba | 2170 | u64 regs[MAX_BPF_EXT_REG] = {}; \ |
b870aa90 AS |
2171 | \ |
2172 | FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \ | |
2173 | ARG1 = (u64) (unsigned long) ctx; \ | |
2ec9898e | 2174 | return ___bpf_prog_run(regs, insn); \ |
f696b8f4 | 2175 | } |
f5bffecd | 2176 | |
1ea47e01 AS |
2177 | #define PROG_NAME_ARGS(stack_size) __bpf_prog_run_args##stack_size |
2178 | #define DEFINE_BPF_PROG_RUN_ARGS(stack_size) \ | |
2179 | static u64 PROG_NAME_ARGS(stack_size)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, \ | |
2180 | const struct bpf_insn *insn) \ | |
2181 | { \ | |
2182 | u64 stack[stack_size / sizeof(u64)]; \ | |
144cd91c | 2183 | u64 regs[MAX_BPF_EXT_REG]; \ |
1ea47e01 AS |
2184 | \ |
2185 | FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \ | |
2186 | BPF_R1 = r1; \ | |
2187 | BPF_R2 = r2; \ | |
2188 | BPF_R3 = r3; \ | |
2189 | BPF_R4 = r4; \ | |
2190 | BPF_R5 = r5; \ | |
2ec9898e | 2191 | return ___bpf_prog_run(regs, insn); \ |
1ea47e01 AS |
2192 | } |
2193 | ||
b870aa90 AS |
2194 | #define EVAL1(FN, X) FN(X) |
2195 | #define EVAL2(FN, X, Y...) FN(X) EVAL1(FN, Y) | |
2196 | #define EVAL3(FN, X, Y...) FN(X) EVAL2(FN, Y) | |
2197 | #define EVAL4(FN, X, Y...) FN(X) EVAL3(FN, Y) | |
2198 | #define EVAL5(FN, X, Y...) FN(X) EVAL4(FN, Y) | |
2199 | #define EVAL6(FN, X, Y...) FN(X) EVAL5(FN, Y) | |
2200 | ||
2201 | EVAL6(DEFINE_BPF_PROG_RUN, 32, 64, 96, 128, 160, 192); | |
2202 | EVAL6(DEFINE_BPF_PROG_RUN, 224, 256, 288, 320, 352, 384); | |
2203 | EVAL4(DEFINE_BPF_PROG_RUN, 416, 448, 480, 512); | |
2204 | ||
1ea47e01 AS |
2205 | EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 32, 64, 96, 128, 160, 192); |
2206 | EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 224, 256, 288, 320, 352, 384); | |
2207 | EVAL4(DEFINE_BPF_PROG_RUN_ARGS, 416, 448, 480, 512); | |
2208 | ||
b870aa90 AS |
2209 | #define PROG_NAME_LIST(stack_size) PROG_NAME(stack_size), |
2210 | ||
2211 | static unsigned int (*interpreters[])(const void *ctx, | |
2212 | const struct bpf_insn *insn) = { | |
2213 | EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192) | |
2214 | EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384) | |
2215 | EVAL4(PROG_NAME_LIST, 416, 448, 480, 512) | |
2216 | }; | |
1ea47e01 AS |
2217 | #undef PROG_NAME_LIST |
2218 | #define PROG_NAME_LIST(stack_size) PROG_NAME_ARGS(stack_size), | |
ba49f976 AB |
2219 | static __maybe_unused |
2220 | u64 (*interpreters_args[])(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, | |
2221 | const struct bpf_insn *insn) = { | |
1ea47e01 AS |
2222 | EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192) |
2223 | EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384) | |
2224 | EVAL4(PROG_NAME_LIST, 416, 448, 480, 512) | |
2225 | }; | |
2226 | #undef PROG_NAME_LIST | |
2227 | ||
ba49f976 | 2228 | #ifdef CONFIG_BPF_SYSCALL |
1ea47e01 AS |
2229 | void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth) |
2230 | { | |
2231 | stack_depth = max_t(u32, stack_depth, 1); | |
2232 | insn->off = (s16) insn->imm; | |
2233 | insn->imm = interpreters_args[(round_up(stack_depth, 32) / 32) - 1] - | |
2234 | __bpf_call_base_args; | |
2235 | insn->code = BPF_JMP | BPF_CALL_ARGS; | |
2236 | } | |
ba49f976 | 2237 | #endif |
290af866 | 2238 | #else |
fa9dd599 DB |
2239 | static unsigned int __bpf_prog_ret0_warn(const void *ctx, |
2240 | const struct bpf_insn *insn) | |
290af866 | 2241 | { |
fa9dd599 DB |
2242 | /* If this handler ever gets executed, then BPF_JIT_ALWAYS_ON |
2243 | * is not working properly, so warn about it! | |
2244 | */ | |
2245 | WARN_ON_ONCE(1); | |
290af866 AS |
2246 | return 0; |
2247 | } | |
2248 | #endif | |
2249 | ||
f45d5b6c THJ |
2250 | bool bpf_prog_map_compatible(struct bpf_map *map, |
2251 | const struct bpf_prog *fp) | |
04fd61ab | 2252 | { |
1c123c56 | 2253 | enum bpf_prog_type prog_type = resolve_prog_type(fp); |
54713c85 THJ |
2254 | bool ret; |
2255 | ||
9802d865 JB |
2256 | if (fp->kprobe_override) |
2257 | return false; | |
2258 | ||
3d76a4d3 SF |
2259 | /* XDP programs inserted into maps are not guaranteed to run on |
2260 | * a particular netdev (and can run outside driver context entirely | |
2261 | * in the case of devmap and cpumap). Until device checks | |
2262 | * are implemented, prohibit adding dev-bound programs to program maps. | |
2263 | */ | |
2264 | if (bpf_prog_is_dev_bound(fp->aux)) | |
2265 | return false; | |
2266 | ||
f45d5b6c THJ |
2267 | spin_lock(&map->owner.lock); |
2268 | if (!map->owner.type) { | |
3324b584 DB |
2269 | /* There's no owner yet where we could check for |
2270 | * compatibility. | |
2271 | */ | |
1c123c56 | 2272 | map->owner.type = prog_type; |
f45d5b6c THJ |
2273 | map->owner.jited = fp->jited; |
2274 | map->owner.xdp_has_frags = fp->aux->xdp_has_frags; | |
54713c85 THJ |
2275 | ret = true; |
2276 | } else { | |
1c123c56 | 2277 | ret = map->owner.type == prog_type && |
f45d5b6c THJ |
2278 | map->owner.jited == fp->jited && |
2279 | map->owner.xdp_has_frags == fp->aux->xdp_has_frags; | |
04fd61ab | 2280 | } |
f45d5b6c THJ |
2281 | spin_unlock(&map->owner.lock); |
2282 | ||
54713c85 | 2283 | return ret; |
04fd61ab AS |
2284 | } |
2285 | ||
3324b584 | 2286 | static int bpf_check_tail_call(const struct bpf_prog *fp) |
04fd61ab AS |
2287 | { |
2288 | struct bpf_prog_aux *aux = fp->aux; | |
984fe94f | 2289 | int i, ret = 0; |
04fd61ab | 2290 | |
984fe94f | 2291 | mutex_lock(&aux->used_maps_mutex); |
04fd61ab | 2292 | for (i = 0; i < aux->used_map_cnt; i++) { |
3324b584 | 2293 | struct bpf_map *map = aux->used_maps[i]; |
04fd61ab | 2294 | |
f45d5b6c | 2295 | if (!map_type_contains_progs(map)) |
04fd61ab | 2296 | continue; |
3324b584 | 2297 | |
f45d5b6c | 2298 | if (!bpf_prog_map_compatible(map, fp)) { |
984fe94f YZ |
2299 | ret = -EINVAL; |
2300 | goto out; | |
2301 | } | |
04fd61ab AS |
2302 | } |
2303 | ||
984fe94f YZ |
2304 | out: |
2305 | mutex_unlock(&aux->used_maps_mutex); | |
2306 | return ret; | |
04fd61ab AS |
2307 | } |
2308 | ||
9facc336 DB |
2309 | static void bpf_prog_select_func(struct bpf_prog *fp) |
2310 | { | |
2311 | #ifndef CONFIG_BPF_JIT_ALWAYS_ON | |
2312 | u32 stack_depth = max_t(u32, fp->aux->stack_depth, 1); | |
2313 | ||
2314 | fp->bpf_func = interpreters[(round_up(stack_depth, 32) / 32) - 1]; | |
2315 | #else | |
2316 | fp->bpf_func = __bpf_prog_ret0_warn; | |
2317 | #endif | |
2318 | } | |
2319 | ||
f5bffecd | 2320 | /** |
3324b584 | 2321 | * bpf_prog_select_runtime - select exec runtime for BPF program |
06edc59c | 2322 | * @fp: bpf_prog populated with BPF program |
d1c55ab5 | 2323 | * @err: pointer to error variable |
f5bffecd | 2324 | * |
3324b584 | 2325 | * Try to JIT eBPF program, if JIT is not available, use interpreter. |
fb7dd8bc | 2326 | * The BPF program will be executed via bpf_prog_run() function. |
019d0454 RD |
2327 | * |
2328 | * Return: the &fp argument along with &err set to 0 for success or | |
2329 | * a negative errno code on failure | |
f5bffecd | 2330 | */ |
d1c55ab5 | 2331 | struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err) |
f5bffecd | 2332 | { |
9facc336 DB |
2333 | /* In case of BPF to BPF calls, verifier did all the prep |
2334 | * work with regards to JITing, etc. | |
2335 | */ | |
e6ac2450 MKL |
2336 | bool jit_needed = false; |
2337 | ||
9facc336 DB |
2338 | if (fp->bpf_func) |
2339 | goto finalize; | |
8007e40a | 2340 | |
e6ac2450 MKL |
2341 | if (IS_ENABLED(CONFIG_BPF_JIT_ALWAYS_ON) || |
2342 | bpf_prog_has_kfunc_call(fp)) | |
2343 | jit_needed = true; | |
2344 | ||
9facc336 | 2345 | bpf_prog_select_func(fp); |
f5bffecd | 2346 | |
d1c55ab5 DB |
2347 | /* eBPF JITs can rewrite the program in case constant |
2348 | * blinding is active. However, in case of error during | |
2349 | * blinding, bpf_int_jit_compile() must always return a | |
2350 | * valid program, which in this case would simply not | |
2351 | * be JITed, but falls back to the interpreter. | |
2352 | */ | |
9d03ebc7 | 2353 | if (!bpf_prog_is_offloaded(fp->aux)) { |
c454a46b MKL |
2354 | *err = bpf_prog_alloc_jited_linfo(fp); |
2355 | if (*err) | |
2356 | return fp; | |
2357 | ||
ab3f0063 | 2358 | fp = bpf_int_jit_compile(fp); |
e16301fb | 2359 | bpf_prog_jit_attempt_done(fp); |
e6ac2450 | 2360 | if (!fp->jited && jit_needed) { |
290af866 AS |
2361 | *err = -ENOTSUPP; |
2362 | return fp; | |
c454a46b | 2363 | } |
ab3f0063 JK |
2364 | } else { |
2365 | *err = bpf_prog_offload_compile(fp); | |
2366 | if (*err) | |
2367 | return fp; | |
2368 | } | |
9facc336 DB |
2369 | |
2370 | finalize: | |
60a3b225 | 2371 | bpf_prog_lock_ro(fp); |
04fd61ab | 2372 | |
3324b584 DB |
2373 | /* The tail call compatibility check can only be done at |
2374 | * this late stage as we need to determine, if we deal | |
2375 | * with JITed or non JITed program concatenations and not | |
2376 | * all eBPF JITs might immediately support all features. | |
2377 | */ | |
d1c55ab5 | 2378 | *err = bpf_check_tail_call(fp); |
85782e03 | 2379 | |
d1c55ab5 | 2380 | return fp; |
f5bffecd | 2381 | } |
7ae457c1 | 2382 | EXPORT_SYMBOL_GPL(bpf_prog_select_runtime); |
f5bffecd | 2383 | |
e87c6bc3 YS |
2384 | static unsigned int __bpf_prog_ret1(const void *ctx, |
2385 | const struct bpf_insn *insn) | |
2386 | { | |
2387 | return 1; | |
2388 | } | |
2389 | ||
2390 | static struct bpf_prog_dummy { | |
2391 | struct bpf_prog prog; | |
2392 | } dummy_bpf_prog = { | |
2393 | .prog = { | |
2394 | .bpf_func = __bpf_prog_ret1, | |
2395 | }, | |
2396 | }; | |
2397 | ||
46531a30 | 2398 | struct bpf_empty_prog_array bpf_empty_prog_array = { |
324bda9e AS |
2399 | .null_prog = NULL, |
2400 | }; | |
46531a30 | 2401 | EXPORT_SYMBOL(bpf_empty_prog_array); |
324bda9e | 2402 | |
d29ab6e1 | 2403 | struct bpf_prog_array *bpf_prog_array_alloc(u32 prog_cnt, gfp_t flags) |
324bda9e AS |
2404 | { |
2405 | if (prog_cnt) | |
2406 | return kzalloc(sizeof(struct bpf_prog_array) + | |
394e40a2 RG |
2407 | sizeof(struct bpf_prog_array_item) * |
2408 | (prog_cnt + 1), | |
324bda9e AS |
2409 | flags); |
2410 | ||
46531a30 | 2411 | return &bpf_empty_prog_array.hdr; |
324bda9e AS |
2412 | } |
2413 | ||
54e9c9d4 | 2414 | void bpf_prog_array_free(struct bpf_prog_array *progs) |
324bda9e | 2415 | { |
46531a30 | 2416 | if (!progs || progs == &bpf_empty_prog_array.hdr) |
324bda9e AS |
2417 | return; |
2418 | kfree_rcu(progs, rcu); | |
2419 | } | |
2420 | ||
8c7dcb84 DK |
2421 | static void __bpf_prog_array_free_sleepable_cb(struct rcu_head *rcu) |
2422 | { | |
2423 | struct bpf_prog_array *progs; | |
2424 | ||
4835f9ee HT |
2425 | /* If RCU Tasks Trace grace period implies RCU grace period, there is |
2426 | * no need to call kfree_rcu(), just call kfree() directly. | |
2427 | */ | |
8c7dcb84 | 2428 | progs = container_of(rcu, struct bpf_prog_array, rcu); |
4835f9ee HT |
2429 | if (rcu_trace_implies_rcu_gp()) |
2430 | kfree(progs); | |
2431 | else | |
2432 | kfree_rcu(progs, rcu); | |
8c7dcb84 DK |
2433 | } |
2434 | ||
2435 | void bpf_prog_array_free_sleepable(struct bpf_prog_array *progs) | |
2436 | { | |
2437 | if (!progs || progs == &bpf_empty_prog_array.hdr) | |
2438 | return; | |
2439 | call_rcu_tasks_trace(&progs->rcu, __bpf_prog_array_free_sleepable_cb); | |
2440 | } | |
2441 | ||
54e9c9d4 | 2442 | int bpf_prog_array_length(struct bpf_prog_array *array) |
468e2f64 | 2443 | { |
394e40a2 | 2444 | struct bpf_prog_array_item *item; |
468e2f64 AS |
2445 | u32 cnt = 0; |
2446 | ||
54e9c9d4 | 2447 | for (item = array->items; item->prog; item++) |
394e40a2 | 2448 | if (item->prog != &dummy_bpf_prog.prog) |
c8c088ba | 2449 | cnt++; |
468e2f64 AS |
2450 | return cnt; |
2451 | } | |
2452 | ||
0d01da6a SF |
2453 | bool bpf_prog_array_is_empty(struct bpf_prog_array *array) |
2454 | { | |
2455 | struct bpf_prog_array_item *item; | |
2456 | ||
2457 | for (item = array->items; item->prog; item++) | |
2458 | if (item->prog != &dummy_bpf_prog.prog) | |
2459 | return false; | |
2460 | return true; | |
2461 | } | |
394e40a2 | 2462 | |
54e9c9d4 | 2463 | static bool bpf_prog_array_copy_core(struct bpf_prog_array *array, |
3a38bb98 YS |
2464 | u32 *prog_ids, |
2465 | u32 request_cnt) | |
2466 | { | |
394e40a2 | 2467 | struct bpf_prog_array_item *item; |
3a38bb98 YS |
2468 | int i = 0; |
2469 | ||
54e9c9d4 | 2470 | for (item = array->items; item->prog; item++) { |
394e40a2 | 2471 | if (item->prog == &dummy_bpf_prog.prog) |
3a38bb98 | 2472 | continue; |
394e40a2 | 2473 | prog_ids[i] = item->prog->aux->id; |
3a38bb98 | 2474 | if (++i == request_cnt) { |
394e40a2 | 2475 | item++; |
3a38bb98 YS |
2476 | break; |
2477 | } | |
2478 | } | |
2479 | ||
394e40a2 | 2480 | return !!(item->prog); |
3a38bb98 YS |
2481 | } |
2482 | ||
54e9c9d4 | 2483 | int bpf_prog_array_copy_to_user(struct bpf_prog_array *array, |
468e2f64 AS |
2484 | __u32 __user *prog_ids, u32 cnt) |
2485 | { | |
0911287c | 2486 | unsigned long err = 0; |
0911287c | 2487 | bool nospc; |
3a38bb98 | 2488 | u32 *ids; |
0911287c AS |
2489 | |
2490 | /* users of this function are doing: | |
2491 | * cnt = bpf_prog_array_length(); | |
2492 | * if (cnt > 0) | |
2493 | * bpf_prog_array_copy_to_user(..., cnt); | |
54e9c9d4 | 2494 | * so below kcalloc doesn't need extra cnt > 0 check. |
0911287c | 2495 | */ |
9c481b90 | 2496 | ids = kcalloc(cnt, sizeof(u32), GFP_USER | __GFP_NOWARN); |
0911287c AS |
2497 | if (!ids) |
2498 | return -ENOMEM; | |
394e40a2 | 2499 | nospc = bpf_prog_array_copy_core(array, ids, cnt); |
0911287c AS |
2500 | err = copy_to_user(prog_ids, ids, cnt * sizeof(u32)); |
2501 | kfree(ids); | |
2502 | if (err) | |
2503 | return -EFAULT; | |
2504 | if (nospc) | |
468e2f64 AS |
2505 | return -ENOSPC; |
2506 | return 0; | |
2507 | } | |
2508 | ||
54e9c9d4 | 2509 | void bpf_prog_array_delete_safe(struct bpf_prog_array *array, |
e87c6bc3 YS |
2510 | struct bpf_prog *old_prog) |
2511 | { | |
54e9c9d4 | 2512 | struct bpf_prog_array_item *item; |
e87c6bc3 | 2513 | |
54e9c9d4 | 2514 | for (item = array->items; item->prog; item++) |
394e40a2 RG |
2515 | if (item->prog == old_prog) { |
2516 | WRITE_ONCE(item->prog, &dummy_bpf_prog.prog); | |
e87c6bc3 YS |
2517 | break; |
2518 | } | |
2519 | } | |
2520 | ||
ce3aa9cc JS |
2521 | /** |
2522 | * bpf_prog_array_delete_safe_at() - Replaces the program at the given | |
2523 | * index into the program array with | |
2524 | * a dummy no-op program. | |
2525 | * @array: a bpf_prog_array | |
2526 | * @index: the index of the program to replace | |
2527 | * | |
2528 | * Skips over dummy programs, by not counting them, when calculating | |
b8c1a309 | 2529 | * the position of the program to replace. |
ce3aa9cc JS |
2530 | * |
2531 | * Return: | |
2532 | * * 0 - Success | |
2533 | * * -EINVAL - Invalid index value. Must be a non-negative integer. | |
2534 | * * -ENOENT - Index out of range | |
2535 | */ | |
2536 | int bpf_prog_array_delete_safe_at(struct bpf_prog_array *array, int index) | |
2537 | { | |
2538 | return bpf_prog_array_update_at(array, index, &dummy_bpf_prog.prog); | |
2539 | } | |
2540 | ||
2541 | /** | |
2542 | * bpf_prog_array_update_at() - Updates the program at the given index | |
2543 | * into the program array. | |
2544 | * @array: a bpf_prog_array | |
2545 | * @index: the index of the program to update | |
2546 | * @prog: the program to insert into the array | |
2547 | * | |
2548 | * Skips over dummy programs, by not counting them, when calculating | |
2549 | * the position of the program to update. | |
2550 | * | |
2551 | * Return: | |
2552 | * * 0 - Success | |
2553 | * * -EINVAL - Invalid index value. Must be a non-negative integer. | |
2554 | * * -ENOENT - Index out of range | |
2555 | */ | |
2556 | int bpf_prog_array_update_at(struct bpf_prog_array *array, int index, | |
2557 | struct bpf_prog *prog) | |
2558 | { | |
2559 | struct bpf_prog_array_item *item; | |
2560 | ||
2561 | if (unlikely(index < 0)) | |
2562 | return -EINVAL; | |
2563 | ||
2564 | for (item = array->items; item->prog; item++) { | |
2565 | if (item->prog == &dummy_bpf_prog.prog) | |
2566 | continue; | |
2567 | if (!index) { | |
2568 | WRITE_ONCE(item->prog, prog); | |
2569 | return 0; | |
2570 | } | |
2571 | index--; | |
2572 | } | |
2573 | return -ENOENT; | |
2574 | } | |
2575 | ||
54e9c9d4 | 2576 | int bpf_prog_array_copy(struct bpf_prog_array *old_array, |
e87c6bc3 YS |
2577 | struct bpf_prog *exclude_prog, |
2578 | struct bpf_prog *include_prog, | |
82e6b1ee | 2579 | u64 bpf_cookie, |
e87c6bc3 YS |
2580 | struct bpf_prog_array **new_array) |
2581 | { | |
2582 | int new_prog_cnt, carry_prog_cnt = 0; | |
82e6b1ee | 2583 | struct bpf_prog_array_item *existing, *new; |
e87c6bc3 | 2584 | struct bpf_prog_array *array; |
170a7e3e | 2585 | bool found_exclude = false; |
e87c6bc3 YS |
2586 | |
2587 | /* Figure out how many existing progs we need to carry over to | |
2588 | * the new array. | |
2589 | */ | |
2590 | if (old_array) { | |
394e40a2 RG |
2591 | existing = old_array->items; |
2592 | for (; existing->prog; existing++) { | |
2593 | if (existing->prog == exclude_prog) { | |
170a7e3e SY |
2594 | found_exclude = true; |
2595 | continue; | |
2596 | } | |
394e40a2 | 2597 | if (existing->prog != &dummy_bpf_prog.prog) |
e87c6bc3 | 2598 | carry_prog_cnt++; |
394e40a2 | 2599 | if (existing->prog == include_prog) |
e87c6bc3 YS |
2600 | return -EEXIST; |
2601 | } | |
2602 | } | |
2603 | ||
170a7e3e SY |
2604 | if (exclude_prog && !found_exclude) |
2605 | return -ENOENT; | |
2606 | ||
e87c6bc3 YS |
2607 | /* How many progs (not NULL) will be in the new array? */ |
2608 | new_prog_cnt = carry_prog_cnt; | |
2609 | if (include_prog) | |
2610 | new_prog_cnt += 1; | |
2611 | ||
2612 | /* Do we have any prog (not NULL) in the new array? */ | |
2613 | if (!new_prog_cnt) { | |
2614 | *new_array = NULL; | |
2615 | return 0; | |
2616 | } | |
2617 | ||
2618 | /* +1 as the end of prog_array is marked with NULL */ | |
2619 | array = bpf_prog_array_alloc(new_prog_cnt + 1, GFP_KERNEL); | |
2620 | if (!array) | |
2621 | return -ENOMEM; | |
82e6b1ee | 2622 | new = array->items; |
e87c6bc3 YS |
2623 | |
2624 | /* Fill in the new prog array */ | |
2625 | if (carry_prog_cnt) { | |
394e40a2 | 2626 | existing = old_array->items; |
82e6b1ee AN |
2627 | for (; existing->prog; existing++) { |
2628 | if (existing->prog == exclude_prog || | |
2629 | existing->prog == &dummy_bpf_prog.prog) | |
2630 | continue; | |
2631 | ||
2632 | new->prog = existing->prog; | |
2633 | new->bpf_cookie = existing->bpf_cookie; | |
2634 | new++; | |
2635 | } | |
e87c6bc3 | 2636 | } |
82e6b1ee AN |
2637 | if (include_prog) { |
2638 | new->prog = include_prog; | |
2639 | new->bpf_cookie = bpf_cookie; | |
2640 | new++; | |
2641 | } | |
2642 | new->prog = NULL; | |
e87c6bc3 YS |
2643 | *new_array = array; |
2644 | return 0; | |
2645 | } | |
2646 | ||
54e9c9d4 | 2647 | int bpf_prog_array_copy_info(struct bpf_prog_array *array, |
3a38bb98 YS |
2648 | u32 *prog_ids, u32 request_cnt, |
2649 | u32 *prog_cnt) | |
f371b304 YS |
2650 | { |
2651 | u32 cnt = 0; | |
2652 | ||
2653 | if (array) | |
2654 | cnt = bpf_prog_array_length(array); | |
2655 | ||
3a38bb98 | 2656 | *prog_cnt = cnt; |
f371b304 YS |
2657 | |
2658 | /* return early if user requested only program count or nothing to copy */ | |
2659 | if (!request_cnt || !cnt) | |
2660 | return 0; | |
2661 | ||
3a38bb98 | 2662 | /* this function is called under trace/bpf_trace.c: bpf_event_mutex */ |
394e40a2 | 2663 | return bpf_prog_array_copy_core(array, prog_ids, request_cnt) ? -ENOSPC |
3a38bb98 | 2664 | : 0; |
f371b304 YS |
2665 | } |
2666 | ||
a2ea0746 DB |
2667 | void __bpf_free_used_maps(struct bpf_prog_aux *aux, |
2668 | struct bpf_map **used_maps, u32 len) | |
6332be04 | 2669 | { |
da765a2f | 2670 | struct bpf_map *map; |
a2ea0746 | 2671 | u32 i; |
6332be04 | 2672 | |
a2ea0746 DB |
2673 | for (i = 0; i < len; i++) { |
2674 | map = used_maps[i]; | |
da765a2f DB |
2675 | if (map->ops->map_poke_untrack) |
2676 | map->ops->map_poke_untrack(map, aux); | |
2677 | bpf_map_put(map); | |
2678 | } | |
a2ea0746 DB |
2679 | } |
2680 | ||
2681 | static void bpf_free_used_maps(struct bpf_prog_aux *aux) | |
2682 | { | |
2683 | __bpf_free_used_maps(aux, aux->used_maps, aux->used_map_cnt); | |
6332be04 DB |
2684 | kfree(aux->used_maps); |
2685 | } | |
2686 | ||
541c3bad AN |
2687 | void __bpf_free_used_btfs(struct bpf_prog_aux *aux, |
2688 | struct btf_mod_pair *used_btfs, u32 len) | |
2689 | { | |
2690 | #ifdef CONFIG_BPF_SYSCALL | |
2691 | struct btf_mod_pair *btf_mod; | |
2692 | u32 i; | |
2693 | ||
2694 | for (i = 0; i < len; i++) { | |
2695 | btf_mod = &used_btfs[i]; | |
2696 | if (btf_mod->module) | |
2697 | module_put(btf_mod->module); | |
2698 | btf_put(btf_mod->btf); | |
2699 | } | |
2700 | #endif | |
2701 | } | |
2702 | ||
2703 | static void bpf_free_used_btfs(struct bpf_prog_aux *aux) | |
2704 | { | |
2705 | __bpf_free_used_btfs(aux, aux->used_btfs, aux->used_btf_cnt); | |
2706 | kfree(aux->used_btfs); | |
2707 | } | |
2708 | ||
60a3b225 DB |
2709 | static void bpf_prog_free_deferred(struct work_struct *work) |
2710 | { | |
09756af4 | 2711 | struct bpf_prog_aux *aux; |
1c2a088a | 2712 | int i; |
60a3b225 | 2713 | |
09756af4 | 2714 | aux = container_of(work, struct bpf_prog_aux, work); |
2357672c KKD |
2715 | #ifdef CONFIG_BPF_SYSCALL |
2716 | bpf_free_kfunc_btf_tab(aux->kfunc_btf_tab); | |
c0e19f2c SF |
2717 | #endif |
2718 | #ifdef CONFIG_CGROUP_BPF | |
2719 | if (aux->cgroup_atype != CGROUP_BPF_ATTACH_TYPE_INVALID) | |
2720 | bpf_cgroup_atype_put(aux->cgroup_atype); | |
2357672c | 2721 | #endif |
6332be04 | 2722 | bpf_free_used_maps(aux); |
541c3bad | 2723 | bpf_free_used_btfs(aux); |
ab3f0063 | 2724 | if (bpf_prog_is_dev_bound(aux)) |
2b3486bc | 2725 | bpf_prog_dev_bound_destroy(aux->prog); |
c195651e YS |
2726 | #ifdef CONFIG_PERF_EVENTS |
2727 | if (aux->prog->has_callchain_buf) | |
2728 | put_callchain_buffers(); | |
2729 | #endif | |
3aac1ead THJ |
2730 | if (aux->dst_trampoline) |
2731 | bpf_trampoline_put(aux->dst_trampoline); | |
335d1c5b | 2732 | for (i = 0; i < aux->real_func_cnt; i++) { |
f263a814 JF |
2733 | /* We can just unlink the subprog poke descriptor table as |
2734 | * it was originally linked to the main program and is also | |
2735 | * released along with it. | |
2736 | */ | |
2737 | aux->func[i]->aux->poke_tab = NULL; | |
1c2a088a | 2738 | bpf_jit_free(aux->func[i]); |
f263a814 | 2739 | } |
335d1c5b | 2740 | if (aux->real_func_cnt) { |
1c2a088a AS |
2741 | kfree(aux->func); |
2742 | bpf_prog_unlock_free(aux->prog); | |
2743 | } else { | |
2744 | bpf_jit_free(aux->prog); | |
2745 | } | |
60a3b225 DB |
2746 | } |
2747 | ||
7ae457c1 | 2748 | void bpf_prog_free(struct bpf_prog *fp) |
f5bffecd | 2749 | { |
09756af4 | 2750 | struct bpf_prog_aux *aux = fp->aux; |
60a3b225 | 2751 | |
3aac1ead THJ |
2752 | if (aux->dst_prog) |
2753 | bpf_prog_put(aux->dst_prog); | |
09756af4 | 2754 | INIT_WORK(&aux->work, bpf_prog_free_deferred); |
09756af4 | 2755 | schedule_work(&aux->work); |
f5bffecd | 2756 | } |
7ae457c1 | 2757 | EXPORT_SYMBOL_GPL(bpf_prog_free); |
f89b7755 | 2758 | |
3ad00405 DB |
2759 | /* RNG for unpriviledged user space with separated state from prandom_u32(). */ |
2760 | static DEFINE_PER_CPU(struct rnd_state, bpf_user_rnd_state); | |
2761 | ||
2762 | void bpf_user_rnd_init_once(void) | |
2763 | { | |
2764 | prandom_init_once(&bpf_user_rnd_state); | |
2765 | } | |
2766 | ||
f3694e00 | 2767 | BPF_CALL_0(bpf_user_rnd_u32) |
3ad00405 DB |
2768 | { |
2769 | /* Should someone ever have the rather unwise idea to use some | |
2770 | * of the registers passed into this function, then note that | |
2771 | * this function is called from native eBPF and classic-to-eBPF | |
2772 | * transformations. Register assignments from both sides are | |
2773 | * different, f.e. classic always sets fn(ctx, A, X) here. | |
2774 | */ | |
2775 | struct rnd_state *state; | |
2776 | u32 res; | |
2777 | ||
2778 | state = &get_cpu_var(bpf_user_rnd_state); | |
2779 | res = prandom_u32_state(state); | |
b761fe22 | 2780 | put_cpu_var(bpf_user_rnd_state); |
3ad00405 DB |
2781 | |
2782 | return res; | |
2783 | } | |
2784 | ||
6890896b SF |
2785 | BPF_CALL_0(bpf_get_raw_cpu_id) |
2786 | { | |
2787 | return raw_smp_processor_id(); | |
2788 | } | |
2789 | ||
3ba67dab DB |
2790 | /* Weak definitions of helper functions in case we don't have bpf syscall. */ |
2791 | const struct bpf_func_proto bpf_map_lookup_elem_proto __weak; | |
2792 | const struct bpf_func_proto bpf_map_update_elem_proto __weak; | |
2793 | const struct bpf_func_proto bpf_map_delete_elem_proto __weak; | |
f1a2e44a MV |
2794 | const struct bpf_func_proto bpf_map_push_elem_proto __weak; |
2795 | const struct bpf_func_proto bpf_map_pop_elem_proto __weak; | |
2796 | const struct bpf_func_proto bpf_map_peek_elem_proto __weak; | |
07343110 | 2797 | const struct bpf_func_proto bpf_map_lookup_percpu_elem_proto __weak; |
d83525ca AS |
2798 | const struct bpf_func_proto bpf_spin_lock_proto __weak; |
2799 | const struct bpf_func_proto bpf_spin_unlock_proto __weak; | |
5576b991 | 2800 | const struct bpf_func_proto bpf_jiffies64_proto __weak; |
3ba67dab | 2801 | |
03e69b50 | 2802 | const struct bpf_func_proto bpf_get_prandom_u32_proto __weak; |
c04167ce | 2803 | const struct bpf_func_proto bpf_get_smp_processor_id_proto __weak; |
2d0e30c3 | 2804 | const struct bpf_func_proto bpf_get_numa_node_id_proto __weak; |
17ca8cbf | 2805 | const struct bpf_func_proto bpf_ktime_get_ns_proto __weak; |
71d19214 | 2806 | const struct bpf_func_proto bpf_ktime_get_boot_ns_proto __weak; |
d0551261 | 2807 | const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto __weak; |
c8996c98 | 2808 | const struct bpf_func_proto bpf_ktime_get_tai_ns_proto __weak; |
bd570ff9 | 2809 | |
ffeedafb AS |
2810 | const struct bpf_func_proto bpf_get_current_pid_tgid_proto __weak; |
2811 | const struct bpf_func_proto bpf_get_current_uid_gid_proto __weak; | |
2812 | const struct bpf_func_proto bpf_get_current_comm_proto __weak; | |
bf6fa2c8 | 2813 | const struct bpf_func_proto bpf_get_current_cgroup_id_proto __weak; |
0f09abd1 | 2814 | const struct bpf_func_proto bpf_get_current_ancestor_cgroup_id_proto __weak; |
cd339431 | 2815 | const struct bpf_func_proto bpf_get_local_storage_proto __weak; |
b4490c5c | 2816 | const struct bpf_func_proto bpf_get_ns_current_pid_tgid_proto __weak; |
c4d0bfb4 | 2817 | const struct bpf_func_proto bpf_snprintf_btf_proto __weak; |
eb411377 | 2818 | const struct bpf_func_proto bpf_seq_printf_btf_proto __weak; |
69fd337a SF |
2819 | const struct bpf_func_proto bpf_set_retval_proto __weak; |
2820 | const struct bpf_func_proto bpf_get_retval_proto __weak; | |
bd570ff9 | 2821 | |
0756ea3e AS |
2822 | const struct bpf_func_proto * __weak bpf_get_trace_printk_proto(void) |
2823 | { | |
2824 | return NULL; | |
2825 | } | |
03e69b50 | 2826 | |
10aceb62 DM |
2827 | const struct bpf_func_proto * __weak bpf_get_trace_vprintk_proto(void) |
2828 | { | |
2829 | return NULL; | |
2830 | } | |
2831 | ||
555c8a86 DB |
2832 | u64 __weak |
2833 | bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size, | |
2834 | void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy) | |
bd570ff9 | 2835 | { |
555c8a86 | 2836 | return -ENOTSUPP; |
bd570ff9 | 2837 | } |
6cb5fb38 | 2838 | EXPORT_SYMBOL_GPL(bpf_event_output); |
bd570ff9 | 2839 | |
3324b584 DB |
2840 | /* Always built-in helper functions. */ |
2841 | const struct bpf_func_proto bpf_tail_call_proto = { | |
2842 | .func = NULL, | |
2843 | .gpl_only = false, | |
2844 | .ret_type = RET_VOID, | |
2845 | .arg1_type = ARG_PTR_TO_CTX, | |
2846 | .arg2_type = ARG_CONST_MAP_PTR, | |
2847 | .arg3_type = ARG_ANYTHING, | |
2848 | }; | |
2849 | ||
9383191d DB |
2850 | /* Stub for JITs that only support cBPF. eBPF programs are interpreted. |
2851 | * It is encouraged to implement bpf_int_jit_compile() instead, so that | |
2852 | * eBPF and implicitly also cBPF can get JITed! | |
2853 | */ | |
d1c55ab5 | 2854 | struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_prog *prog) |
3324b584 | 2855 | { |
d1c55ab5 | 2856 | return prog; |
3324b584 DB |
2857 | } |
2858 | ||
9383191d DB |
2859 | /* Stub for JITs that support eBPF. All cBPF code gets transformed into |
2860 | * eBPF by the kernel and is later compiled by bpf_int_jit_compile(). | |
2861 | */ | |
2862 | void __weak bpf_jit_compile(struct bpf_prog *prog) | |
2863 | { | |
2864 | } | |
2865 | ||
17bedab2 | 2866 | bool __weak bpf_helper_changes_pkt_data(void *func) |
969bf05e AS |
2867 | { |
2868 | return false; | |
2869 | } | |
2870 | ||
a4b1d3c1 JW |
2871 | /* Return TRUE if the JIT backend wants verifier to enable sub-register usage |
2872 | * analysis code and wants explicit zero extension inserted by verifier. | |
2873 | * Otherwise, return FALSE. | |
39491867 BJ |
2874 | * |
2875 | * The verifier inserts an explicit zero extension after BPF_CMPXCHGs even if | |
2876 | * you don't override this. JITs that don't want these extra insns can detect | |
2877 | * them using insn_is_zext. | |
a4b1d3c1 JW |
2878 | */ |
2879 | bool __weak bpf_jit_needs_zext(void) | |
2880 | { | |
2881 | return false; | |
2882 | } | |
2883 | ||
95acd881 TA |
2884 | /* Return TRUE if the JIT backend supports mixing bpf2bpf and tailcalls. */ |
2885 | bool __weak bpf_jit_supports_subprog_tailcalls(void) | |
2886 | { | |
2887 | return false; | |
2888 | } | |
2889 | ||
e6ac2450 MKL |
2890 | bool __weak bpf_jit_supports_kfunc_call(void) |
2891 | { | |
2892 | return false; | |
2893 | } | |
2894 | ||
1cf3bfc6 IL |
2895 | bool __weak bpf_jit_supports_far_kfunc_call(void) |
2896 | { | |
2897 | return false; | |
2898 | } | |
2899 | ||
f89b7755 AS |
2900 | /* To execute LD_ABS/LD_IND instructions __bpf_prog_run() may call |
2901 | * skb_copy_bits(), so provide a weak definition of it for NET-less config. | |
2902 | */ | |
2903 | int __weak skb_copy_bits(const struct sk_buff *skb, int offset, void *to, | |
2904 | int len) | |
2905 | { | |
2906 | return -EFAULT; | |
2907 | } | |
a67edbf4 | 2908 | |
5964b200 AS |
2909 | int __weak bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t, |
2910 | void *addr1, void *addr2) | |
2911 | { | |
2912 | return -ENOTSUPP; | |
2913 | } | |
2914 | ||
ebc1415d SL |
2915 | void * __weak bpf_arch_text_copy(void *dst, void *src, size_t len) |
2916 | { | |
2917 | return ERR_PTR(-ENOTSUPP); | |
2918 | } | |
2919 | ||
fe736565 SL |
2920 | int __weak bpf_arch_text_invalidate(void *dst, size_t len) |
2921 | { | |
2922 | return -ENOTSUPP; | |
2923 | } | |
2924 | ||
fd5d27b7 KKD |
2925 | bool __weak bpf_jit_supports_exceptions(void) |
2926 | { | |
2927 | return false; | |
2928 | } | |
2929 | ||
2930 | void __weak arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie) | |
2931 | { | |
2932 | } | |
2933 | ||
958cf2e2 KKD |
2934 | #ifdef CONFIG_BPF_SYSCALL |
2935 | static int __init bpf_global_ma_init(void) | |
2936 | { | |
2937 | int ret; | |
2938 | ||
2939 | ret = bpf_mem_alloc_init(&bpf_global_ma, 0, false); | |
2940 | bpf_global_ma_set = !ret; | |
1fda5bb6 | 2941 | return ret; |
958cf2e2 KKD |
2942 | } |
2943 | late_initcall(bpf_global_ma_init); | |
2944 | #endif | |
2945 | ||
492ecee8 AS |
2946 | DEFINE_STATIC_KEY_FALSE(bpf_stats_enabled_key); |
2947 | EXPORT_SYMBOL(bpf_stats_enabled_key); | |
492ecee8 | 2948 | |
a67edbf4 DB |
2949 | /* All definitions of tracepoints related to BPF. */ |
2950 | #define CREATE_TRACE_POINTS | |
2951 | #include <linux/bpf_trace.h> | |
2952 | ||
2953 | EXPORT_TRACEPOINT_SYMBOL_GPL(xdp_exception); | |
e7d47989 | 2954 | EXPORT_TRACEPOINT_SYMBOL_GPL(xdp_bulk_tx); |