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[mirror_ubuntu-focal-kernel.git] / arch / x86 / net / bpf_jit_comp.c
1 /* bpf_jit_comp.c : BPF JIT compiler
2 *
3 * Copyright (C) 2011-2013 Eric Dumazet (eric.dumazet@gmail.com)
4 * Internal BPF Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; version 2
9 * of the License.
10 */
11 #include <linux/netdevice.h>
12 #include <linux/filter.h>
13 #include <linux/if_vlan.h>
14 #include <asm/cacheflush.h>
15 #include <asm/set_memory.h>
16 #include <linux/bpf.h>
17
18 int bpf_jit_enable __read_mostly;
19
20 /*
21 * assembly code in arch/x86/net/bpf_jit.S
22 */
23 extern u8 sk_load_word[], sk_load_half[], sk_load_byte[];
24 extern u8 sk_load_word_positive_offset[], sk_load_half_positive_offset[];
25 extern u8 sk_load_byte_positive_offset[];
26 extern u8 sk_load_word_negative_offset[], sk_load_half_negative_offset[];
27 extern u8 sk_load_byte_negative_offset[];
28
29 static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len)
30 {
31 if (len == 1)
32 *ptr = bytes;
33 else if (len == 2)
34 *(u16 *)ptr = bytes;
35 else {
36 *(u32 *)ptr = bytes;
37 barrier();
38 }
39 return ptr + len;
40 }
41
42 #define EMIT(bytes, len) \
43 do { prog = emit_code(prog, bytes, len); cnt += len; } while (0)
44
45 #define EMIT1(b1) EMIT(b1, 1)
46 #define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2)
47 #define EMIT3(b1, b2, b3) EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3)
48 #define EMIT4(b1, b2, b3, b4) EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4)
49 #define EMIT1_off32(b1, off) \
50 do {EMIT1(b1); EMIT(off, 4); } while (0)
51 #define EMIT2_off32(b1, b2, off) \
52 do {EMIT2(b1, b2); EMIT(off, 4); } while (0)
53 #define EMIT3_off32(b1, b2, b3, off) \
54 do {EMIT3(b1, b2, b3); EMIT(off, 4); } while (0)
55 #define EMIT4_off32(b1, b2, b3, b4, off) \
56 do {EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0)
57
58 static bool is_imm8(int value)
59 {
60 return value <= 127 && value >= -128;
61 }
62
63 static bool is_simm32(s64 value)
64 {
65 return value == (s64) (s32) value;
66 }
67
68 /* mov dst, src */
69 #define EMIT_mov(DST, SRC) \
70 do {if (DST != SRC) \
71 EMIT3(add_2mod(0x48, DST, SRC), 0x89, add_2reg(0xC0, DST, SRC)); \
72 } while (0)
73
74 static int bpf_size_to_x86_bytes(int bpf_size)
75 {
76 if (bpf_size == BPF_W)
77 return 4;
78 else if (bpf_size == BPF_H)
79 return 2;
80 else if (bpf_size == BPF_B)
81 return 1;
82 else if (bpf_size == BPF_DW)
83 return 4; /* imm32 */
84 else
85 return 0;
86 }
87
88 /* list of x86 cond jumps opcodes (. + s8)
89 * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32)
90 */
91 #define X86_JB 0x72
92 #define X86_JAE 0x73
93 #define X86_JE 0x74
94 #define X86_JNE 0x75
95 #define X86_JBE 0x76
96 #define X86_JA 0x77
97 #define X86_JL 0x7C
98 #define X86_JGE 0x7D
99 #define X86_JLE 0x7E
100 #define X86_JG 0x7F
101
102 static void bpf_flush_icache(void *start, void *end)
103 {
104 mm_segment_t old_fs = get_fs();
105
106 set_fs(KERNEL_DS);
107 smp_wmb();
108 flush_icache_range((unsigned long)start, (unsigned long)end);
109 set_fs(old_fs);
110 }
111
112 #define CHOOSE_LOAD_FUNC(K, func) \
113 ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset)
114
115 /* pick a register outside of BPF range for JIT internal work */
116 #define AUX_REG (MAX_BPF_JIT_REG + 1)
117
118 /* The following table maps BPF registers to x64 registers.
119 *
120 * x64 register r12 is unused, since if used as base address
121 * register in load/store instructions, it always needs an
122 * extra byte of encoding and is callee saved.
123 *
124 * r9 caches skb->len - skb->data_len
125 * r10 caches skb->data, and used for blinding (if enabled)
126 */
127 static const int reg2hex[] = {
128 [BPF_REG_0] = 0, /* rax */
129 [BPF_REG_1] = 7, /* rdi */
130 [BPF_REG_2] = 6, /* rsi */
131 [BPF_REG_3] = 2, /* rdx */
132 [BPF_REG_4] = 1, /* rcx */
133 [BPF_REG_5] = 0, /* r8 */
134 [BPF_REG_6] = 3, /* rbx callee saved */
135 [BPF_REG_7] = 5, /* r13 callee saved */
136 [BPF_REG_8] = 6, /* r14 callee saved */
137 [BPF_REG_9] = 7, /* r15 callee saved */
138 [BPF_REG_FP] = 5, /* rbp readonly */
139 [BPF_REG_AX] = 2, /* r10 temp register */
140 [AUX_REG] = 3, /* r11 temp register */
141 };
142
143 /* is_ereg() == true if BPF register 'reg' maps to x64 r8..r15
144 * which need extra byte of encoding.
145 * rax,rcx,...,rbp have simpler encoding
146 */
147 static bool is_ereg(u32 reg)
148 {
149 return (1 << reg) & (BIT(BPF_REG_5) |
150 BIT(AUX_REG) |
151 BIT(BPF_REG_7) |
152 BIT(BPF_REG_8) |
153 BIT(BPF_REG_9) |
154 BIT(BPF_REG_AX));
155 }
156
157 /* add modifiers if 'reg' maps to x64 registers r8..r15 */
158 static u8 add_1mod(u8 byte, u32 reg)
159 {
160 if (is_ereg(reg))
161 byte |= 1;
162 return byte;
163 }
164
165 static u8 add_2mod(u8 byte, u32 r1, u32 r2)
166 {
167 if (is_ereg(r1))
168 byte |= 1;
169 if (is_ereg(r2))
170 byte |= 4;
171 return byte;
172 }
173
174 /* encode 'dst_reg' register into x64 opcode 'byte' */
175 static u8 add_1reg(u8 byte, u32 dst_reg)
176 {
177 return byte + reg2hex[dst_reg];
178 }
179
180 /* encode 'dst_reg' and 'src_reg' registers into x64 opcode 'byte' */
181 static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg)
182 {
183 return byte + reg2hex[dst_reg] + (reg2hex[src_reg] << 3);
184 }
185
186 static void jit_fill_hole(void *area, unsigned int size)
187 {
188 /* fill whole space with int3 instructions */
189 memset(area, 0xcc, size);
190 }
191
192 struct jit_context {
193 int cleanup_addr; /* epilogue code offset */
194 bool seen_ld_abs;
195 bool seen_ax_reg;
196 };
197
198 /* maximum number of bytes emitted while JITing one eBPF insn */
199 #define BPF_MAX_INSN_SIZE 128
200 #define BPF_INSN_SAFETY 64
201
202 #define AUX_STACK_SPACE \
203 (32 /* space for rbx, r13, r14, r15 */ + \
204 8 /* space for skb_copy_bits() buffer */)
205
206 #define PROLOGUE_SIZE 37
207
208 /* emit x64 prologue code for BPF program and check it's size.
209 * bpf_tail_call helper will skip it while jumping into another program
210 */
211 static void emit_prologue(u8 **pprog, u32 stack_depth)
212 {
213 u8 *prog = *pprog;
214 int cnt = 0;
215
216 EMIT1(0x55); /* push rbp */
217 EMIT3(0x48, 0x89, 0xE5); /* mov rbp,rsp */
218
219 /* sub rsp, rounded_stack_depth + AUX_STACK_SPACE */
220 EMIT3_off32(0x48, 0x81, 0xEC,
221 round_up(stack_depth, 8) + AUX_STACK_SPACE);
222
223 /* sub rbp, AUX_STACK_SPACE */
224 EMIT4(0x48, 0x83, 0xED, AUX_STACK_SPACE);
225
226 /* all classic BPF filters use R6(rbx) save it */
227
228 /* mov qword ptr [rbp+0],rbx */
229 EMIT4(0x48, 0x89, 0x5D, 0);
230
231 /* bpf_convert_filter() maps classic BPF register X to R7 and uses R8
232 * as temporary, so all tcpdump filters need to spill/fill R7(r13) and
233 * R8(r14). R9(r15) spill could be made conditional, but there is only
234 * one 'bpf_error' return path out of helper functions inside bpf_jit.S
235 * The overhead of extra spill is negligible for any filter other
236 * than synthetic ones. Therefore not worth adding complexity.
237 */
238
239 /* mov qword ptr [rbp+8],r13 */
240 EMIT4(0x4C, 0x89, 0x6D, 8);
241 /* mov qword ptr [rbp+16],r14 */
242 EMIT4(0x4C, 0x89, 0x75, 16);
243 /* mov qword ptr [rbp+24],r15 */
244 EMIT4(0x4C, 0x89, 0x7D, 24);
245
246 /* Clear the tail call counter (tail_call_cnt): for eBPF tail calls
247 * we need to reset the counter to 0. It's done in two instructions,
248 * resetting rax register to 0 (xor on eax gets 0 extended), and
249 * moving it to the counter location.
250 */
251
252 /* xor eax, eax */
253 EMIT2(0x31, 0xc0);
254 /* mov qword ptr [rbp+32], rax */
255 EMIT4(0x48, 0x89, 0x45, 32);
256
257 BUILD_BUG_ON(cnt != PROLOGUE_SIZE);
258 *pprog = prog;
259 }
260
261 /* generate the following code:
262 * ... bpf_tail_call(void *ctx, struct bpf_array *array, u64 index) ...
263 * if (index >= array->map.max_entries)
264 * goto out;
265 * if (++tail_call_cnt > MAX_TAIL_CALL_CNT)
266 * goto out;
267 * prog = array->ptrs[index];
268 * if (prog == NULL)
269 * goto out;
270 * goto *(prog->bpf_func + prologue_size);
271 * out:
272 */
273 static void emit_bpf_tail_call(u8 **pprog)
274 {
275 u8 *prog = *pprog;
276 int label1, label2, label3;
277 int cnt = 0;
278
279 /* rdi - pointer to ctx
280 * rsi - pointer to bpf_array
281 * rdx - index in bpf_array
282 */
283
284 /* if (index >= array->map.max_entries)
285 * goto out;
286 */
287 EMIT2(0x89, 0xD2); /* mov edx, edx */
288 EMIT3(0x39, 0x56, /* cmp dword ptr [rsi + 16], edx */
289 offsetof(struct bpf_array, map.max_entries));
290 #define OFFSET1 43 /* number of bytes to jump */
291 EMIT2(X86_JBE, OFFSET1); /* jbe out */
292 label1 = cnt;
293
294 /* if (tail_call_cnt > MAX_TAIL_CALL_CNT)
295 * goto out;
296 */
297 EMIT2_off32(0x8B, 0x85, 36); /* mov eax, dword ptr [rbp + 36] */
298 EMIT3(0x83, 0xF8, MAX_TAIL_CALL_CNT); /* cmp eax, MAX_TAIL_CALL_CNT */
299 #define OFFSET2 32
300 EMIT2(X86_JA, OFFSET2); /* ja out */
301 label2 = cnt;
302 EMIT3(0x83, 0xC0, 0x01); /* add eax, 1 */
303 EMIT2_off32(0x89, 0x85, 36); /* mov dword ptr [rbp + 36], eax */
304
305 /* prog = array->ptrs[index]; */
306 EMIT4_off32(0x48, 0x8B, 0x84, 0xD6, /* mov rax, [rsi + rdx * 8 + offsetof(...)] */
307 offsetof(struct bpf_array, ptrs));
308
309 /* if (prog == NULL)
310 * goto out;
311 */
312 EMIT3(0x48, 0x85, 0xC0); /* test rax,rax */
313 #define OFFSET3 10
314 EMIT2(X86_JE, OFFSET3); /* je out */
315 label3 = cnt;
316
317 /* goto *(prog->bpf_func + prologue_size); */
318 EMIT4(0x48, 0x8B, 0x40, /* mov rax, qword ptr [rax + 32] */
319 offsetof(struct bpf_prog, bpf_func));
320 EMIT4(0x48, 0x83, 0xC0, PROLOGUE_SIZE); /* add rax, prologue_size */
321
322 /* now we're ready to jump into next BPF program
323 * rdi == ctx (1st arg)
324 * rax == prog->bpf_func + prologue_size
325 */
326 EMIT2(0xFF, 0xE0); /* jmp rax */
327
328 /* out: */
329 BUILD_BUG_ON(cnt - label1 != OFFSET1);
330 BUILD_BUG_ON(cnt - label2 != OFFSET2);
331 BUILD_BUG_ON(cnt - label3 != OFFSET3);
332 *pprog = prog;
333 }
334
335
336 static void emit_load_skb_data_hlen(u8 **pprog)
337 {
338 u8 *prog = *pprog;
339 int cnt = 0;
340
341 /* r9d = skb->len - skb->data_len (headlen)
342 * r10 = skb->data
343 */
344 /* mov %r9d, off32(%rdi) */
345 EMIT3_off32(0x44, 0x8b, 0x8f, offsetof(struct sk_buff, len));
346
347 /* sub %r9d, off32(%rdi) */
348 EMIT3_off32(0x44, 0x2b, 0x8f, offsetof(struct sk_buff, data_len));
349
350 /* mov %r10, off32(%rdi) */
351 EMIT3_off32(0x4c, 0x8b, 0x97, offsetof(struct sk_buff, data));
352 *pprog = prog;
353 }
354
355 static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
356 int oldproglen, struct jit_context *ctx)
357 {
358 struct bpf_insn *insn = bpf_prog->insnsi;
359 int insn_cnt = bpf_prog->len;
360 bool seen_ld_abs = ctx->seen_ld_abs | (oldproglen == 0);
361 bool seen_ax_reg = ctx->seen_ax_reg | (oldproglen == 0);
362 bool seen_exit = false;
363 u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY];
364 int i, cnt = 0;
365 int proglen = 0;
366 u8 *prog = temp;
367
368 emit_prologue(&prog, bpf_prog->aux->stack_depth);
369
370 if (seen_ld_abs)
371 emit_load_skb_data_hlen(&prog);
372
373 for (i = 0; i < insn_cnt; i++, insn++) {
374 const s32 imm32 = insn->imm;
375 u32 dst_reg = insn->dst_reg;
376 u32 src_reg = insn->src_reg;
377 u8 b1 = 0, b2 = 0, b3 = 0;
378 s64 jmp_offset;
379 u8 jmp_cond;
380 bool reload_skb_data;
381 int ilen;
382 u8 *func;
383
384 if (dst_reg == BPF_REG_AX || src_reg == BPF_REG_AX)
385 ctx->seen_ax_reg = seen_ax_reg = true;
386
387 switch (insn->code) {
388 /* ALU */
389 case BPF_ALU | BPF_ADD | BPF_X:
390 case BPF_ALU | BPF_SUB | BPF_X:
391 case BPF_ALU | BPF_AND | BPF_X:
392 case BPF_ALU | BPF_OR | BPF_X:
393 case BPF_ALU | BPF_XOR | BPF_X:
394 case BPF_ALU64 | BPF_ADD | BPF_X:
395 case BPF_ALU64 | BPF_SUB | BPF_X:
396 case BPF_ALU64 | BPF_AND | BPF_X:
397 case BPF_ALU64 | BPF_OR | BPF_X:
398 case BPF_ALU64 | BPF_XOR | BPF_X:
399 switch (BPF_OP(insn->code)) {
400 case BPF_ADD: b2 = 0x01; break;
401 case BPF_SUB: b2 = 0x29; break;
402 case BPF_AND: b2 = 0x21; break;
403 case BPF_OR: b2 = 0x09; break;
404 case BPF_XOR: b2 = 0x31; break;
405 }
406 if (BPF_CLASS(insn->code) == BPF_ALU64)
407 EMIT1(add_2mod(0x48, dst_reg, src_reg));
408 else if (is_ereg(dst_reg) || is_ereg(src_reg))
409 EMIT1(add_2mod(0x40, dst_reg, src_reg));
410 EMIT2(b2, add_2reg(0xC0, dst_reg, src_reg));
411 break;
412
413 /* mov dst, src */
414 case BPF_ALU64 | BPF_MOV | BPF_X:
415 EMIT_mov(dst_reg, src_reg);
416 break;
417
418 /* mov32 dst, src */
419 case BPF_ALU | BPF_MOV | BPF_X:
420 if (is_ereg(dst_reg) || is_ereg(src_reg))
421 EMIT1(add_2mod(0x40, dst_reg, src_reg));
422 EMIT2(0x89, add_2reg(0xC0, dst_reg, src_reg));
423 break;
424
425 /* neg dst */
426 case BPF_ALU | BPF_NEG:
427 case BPF_ALU64 | BPF_NEG:
428 if (BPF_CLASS(insn->code) == BPF_ALU64)
429 EMIT1(add_1mod(0x48, dst_reg));
430 else if (is_ereg(dst_reg))
431 EMIT1(add_1mod(0x40, dst_reg));
432 EMIT2(0xF7, add_1reg(0xD8, dst_reg));
433 break;
434
435 case BPF_ALU | BPF_ADD | BPF_K:
436 case BPF_ALU | BPF_SUB | BPF_K:
437 case BPF_ALU | BPF_AND | BPF_K:
438 case BPF_ALU | BPF_OR | BPF_K:
439 case BPF_ALU | BPF_XOR | BPF_K:
440 case BPF_ALU64 | BPF_ADD | BPF_K:
441 case BPF_ALU64 | BPF_SUB | BPF_K:
442 case BPF_ALU64 | BPF_AND | BPF_K:
443 case BPF_ALU64 | BPF_OR | BPF_K:
444 case BPF_ALU64 | BPF_XOR | BPF_K:
445 if (BPF_CLASS(insn->code) == BPF_ALU64)
446 EMIT1(add_1mod(0x48, dst_reg));
447 else if (is_ereg(dst_reg))
448 EMIT1(add_1mod(0x40, dst_reg));
449
450 switch (BPF_OP(insn->code)) {
451 case BPF_ADD: b3 = 0xC0; break;
452 case BPF_SUB: b3 = 0xE8; break;
453 case BPF_AND: b3 = 0xE0; break;
454 case BPF_OR: b3 = 0xC8; break;
455 case BPF_XOR: b3 = 0xF0; break;
456 }
457
458 if (is_imm8(imm32))
459 EMIT3(0x83, add_1reg(b3, dst_reg), imm32);
460 else
461 EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32);
462 break;
463
464 case BPF_ALU64 | BPF_MOV | BPF_K:
465 /* optimization: if imm32 is positive,
466 * use 'mov eax, imm32' (which zero-extends imm32)
467 * to save 2 bytes
468 */
469 if (imm32 < 0) {
470 /* 'mov rax, imm32' sign extends imm32 */
471 b1 = add_1mod(0x48, dst_reg);
472 b2 = 0xC7;
473 b3 = 0xC0;
474 EMIT3_off32(b1, b2, add_1reg(b3, dst_reg), imm32);
475 break;
476 }
477
478 case BPF_ALU | BPF_MOV | BPF_K:
479 /* optimization: if imm32 is zero, use 'xor <dst>,<dst>'
480 * to save 3 bytes.
481 */
482 if (imm32 == 0) {
483 if (is_ereg(dst_reg))
484 EMIT1(add_2mod(0x40, dst_reg, dst_reg));
485 b2 = 0x31; /* xor */
486 b3 = 0xC0;
487 EMIT2(b2, add_2reg(b3, dst_reg, dst_reg));
488 break;
489 }
490
491 /* mov %eax, imm32 */
492 if (is_ereg(dst_reg))
493 EMIT1(add_1mod(0x40, dst_reg));
494 EMIT1_off32(add_1reg(0xB8, dst_reg), imm32);
495 break;
496
497 case BPF_LD | BPF_IMM | BPF_DW:
498 /* optimization: if imm64 is zero, use 'xor <dst>,<dst>'
499 * to save 7 bytes.
500 */
501 if (insn[0].imm == 0 && insn[1].imm == 0) {
502 b1 = add_2mod(0x48, dst_reg, dst_reg);
503 b2 = 0x31; /* xor */
504 b3 = 0xC0;
505 EMIT3(b1, b2, add_2reg(b3, dst_reg, dst_reg));
506
507 insn++;
508 i++;
509 break;
510 }
511
512 /* movabsq %rax, imm64 */
513 EMIT2(add_1mod(0x48, dst_reg), add_1reg(0xB8, dst_reg));
514 EMIT(insn[0].imm, 4);
515 EMIT(insn[1].imm, 4);
516
517 insn++;
518 i++;
519 break;
520
521 /* dst %= src, dst /= src, dst %= imm32, dst /= imm32 */
522 case BPF_ALU | BPF_MOD | BPF_X:
523 case BPF_ALU | BPF_DIV | BPF_X:
524 case BPF_ALU | BPF_MOD | BPF_K:
525 case BPF_ALU | BPF_DIV | BPF_K:
526 case BPF_ALU64 | BPF_MOD | BPF_X:
527 case BPF_ALU64 | BPF_DIV | BPF_X:
528 case BPF_ALU64 | BPF_MOD | BPF_K:
529 case BPF_ALU64 | BPF_DIV | BPF_K:
530 EMIT1(0x50); /* push rax */
531 EMIT1(0x52); /* push rdx */
532
533 if (BPF_SRC(insn->code) == BPF_X)
534 /* mov r11, src_reg */
535 EMIT_mov(AUX_REG, src_reg);
536 else
537 /* mov r11, imm32 */
538 EMIT3_off32(0x49, 0xC7, 0xC3, imm32);
539
540 /* mov rax, dst_reg */
541 EMIT_mov(BPF_REG_0, dst_reg);
542
543 /* xor edx, edx
544 * equivalent to 'xor rdx, rdx', but one byte less
545 */
546 EMIT2(0x31, 0xd2);
547
548 if (BPF_SRC(insn->code) == BPF_X) {
549 /* if (src_reg == 0) return 0 */
550
551 /* cmp r11, 0 */
552 EMIT4(0x49, 0x83, 0xFB, 0x00);
553
554 /* jne .+9 (skip over pop, pop, xor and jmp) */
555 EMIT2(X86_JNE, 1 + 1 + 2 + 5);
556 EMIT1(0x5A); /* pop rdx */
557 EMIT1(0x58); /* pop rax */
558 EMIT2(0x31, 0xc0); /* xor eax, eax */
559
560 /* jmp cleanup_addr
561 * addrs[i] - 11, because there are 11 bytes
562 * after this insn: div, mov, pop, pop, mov
563 */
564 jmp_offset = ctx->cleanup_addr - (addrs[i] - 11);
565 EMIT1_off32(0xE9, jmp_offset);
566 }
567
568 if (BPF_CLASS(insn->code) == BPF_ALU64)
569 /* div r11 */
570 EMIT3(0x49, 0xF7, 0xF3);
571 else
572 /* div r11d */
573 EMIT3(0x41, 0xF7, 0xF3);
574
575 if (BPF_OP(insn->code) == BPF_MOD)
576 /* mov r11, rdx */
577 EMIT3(0x49, 0x89, 0xD3);
578 else
579 /* mov r11, rax */
580 EMIT3(0x49, 0x89, 0xC3);
581
582 EMIT1(0x5A); /* pop rdx */
583 EMIT1(0x58); /* pop rax */
584
585 /* mov dst_reg, r11 */
586 EMIT_mov(dst_reg, AUX_REG);
587 break;
588
589 case BPF_ALU | BPF_MUL | BPF_K:
590 case BPF_ALU | BPF_MUL | BPF_X:
591 case BPF_ALU64 | BPF_MUL | BPF_K:
592 case BPF_ALU64 | BPF_MUL | BPF_X:
593 EMIT1(0x50); /* push rax */
594 EMIT1(0x52); /* push rdx */
595
596 /* mov r11, dst_reg */
597 EMIT_mov(AUX_REG, dst_reg);
598
599 if (BPF_SRC(insn->code) == BPF_X)
600 /* mov rax, src_reg */
601 EMIT_mov(BPF_REG_0, src_reg);
602 else
603 /* mov rax, imm32 */
604 EMIT3_off32(0x48, 0xC7, 0xC0, imm32);
605
606 if (BPF_CLASS(insn->code) == BPF_ALU64)
607 EMIT1(add_1mod(0x48, AUX_REG));
608 else if (is_ereg(AUX_REG))
609 EMIT1(add_1mod(0x40, AUX_REG));
610 /* mul(q) r11 */
611 EMIT2(0xF7, add_1reg(0xE0, AUX_REG));
612
613 /* mov r11, rax */
614 EMIT_mov(AUX_REG, BPF_REG_0);
615
616 EMIT1(0x5A); /* pop rdx */
617 EMIT1(0x58); /* pop rax */
618
619 /* mov dst_reg, r11 */
620 EMIT_mov(dst_reg, AUX_REG);
621 break;
622
623 /* shifts */
624 case BPF_ALU | BPF_LSH | BPF_K:
625 case BPF_ALU | BPF_RSH | BPF_K:
626 case BPF_ALU | BPF_ARSH | BPF_K:
627 case BPF_ALU64 | BPF_LSH | BPF_K:
628 case BPF_ALU64 | BPF_RSH | BPF_K:
629 case BPF_ALU64 | BPF_ARSH | BPF_K:
630 if (BPF_CLASS(insn->code) == BPF_ALU64)
631 EMIT1(add_1mod(0x48, dst_reg));
632 else if (is_ereg(dst_reg))
633 EMIT1(add_1mod(0x40, dst_reg));
634
635 switch (BPF_OP(insn->code)) {
636 case BPF_LSH: b3 = 0xE0; break;
637 case BPF_RSH: b3 = 0xE8; break;
638 case BPF_ARSH: b3 = 0xF8; break;
639 }
640 EMIT3(0xC1, add_1reg(b3, dst_reg), imm32);
641 break;
642
643 case BPF_ALU | BPF_LSH | BPF_X:
644 case BPF_ALU | BPF_RSH | BPF_X:
645 case BPF_ALU | BPF_ARSH | BPF_X:
646 case BPF_ALU64 | BPF_LSH | BPF_X:
647 case BPF_ALU64 | BPF_RSH | BPF_X:
648 case BPF_ALU64 | BPF_ARSH | BPF_X:
649
650 /* check for bad case when dst_reg == rcx */
651 if (dst_reg == BPF_REG_4) {
652 /* mov r11, dst_reg */
653 EMIT_mov(AUX_REG, dst_reg);
654 dst_reg = AUX_REG;
655 }
656
657 if (src_reg != BPF_REG_4) { /* common case */
658 EMIT1(0x51); /* push rcx */
659
660 /* mov rcx, src_reg */
661 EMIT_mov(BPF_REG_4, src_reg);
662 }
663
664 /* shl %rax, %cl | shr %rax, %cl | sar %rax, %cl */
665 if (BPF_CLASS(insn->code) == BPF_ALU64)
666 EMIT1(add_1mod(0x48, dst_reg));
667 else if (is_ereg(dst_reg))
668 EMIT1(add_1mod(0x40, dst_reg));
669
670 switch (BPF_OP(insn->code)) {
671 case BPF_LSH: b3 = 0xE0; break;
672 case BPF_RSH: b3 = 0xE8; break;
673 case BPF_ARSH: b3 = 0xF8; break;
674 }
675 EMIT2(0xD3, add_1reg(b3, dst_reg));
676
677 if (src_reg != BPF_REG_4)
678 EMIT1(0x59); /* pop rcx */
679
680 if (insn->dst_reg == BPF_REG_4)
681 /* mov dst_reg, r11 */
682 EMIT_mov(insn->dst_reg, AUX_REG);
683 break;
684
685 case BPF_ALU | BPF_END | BPF_FROM_BE:
686 switch (imm32) {
687 case 16:
688 /* emit 'ror %ax, 8' to swap lower 2 bytes */
689 EMIT1(0x66);
690 if (is_ereg(dst_reg))
691 EMIT1(0x41);
692 EMIT3(0xC1, add_1reg(0xC8, dst_reg), 8);
693
694 /* emit 'movzwl eax, ax' */
695 if (is_ereg(dst_reg))
696 EMIT3(0x45, 0x0F, 0xB7);
697 else
698 EMIT2(0x0F, 0xB7);
699 EMIT1(add_2reg(0xC0, dst_reg, dst_reg));
700 break;
701 case 32:
702 /* emit 'bswap eax' to swap lower 4 bytes */
703 if (is_ereg(dst_reg))
704 EMIT2(0x41, 0x0F);
705 else
706 EMIT1(0x0F);
707 EMIT1(add_1reg(0xC8, dst_reg));
708 break;
709 case 64:
710 /* emit 'bswap rax' to swap 8 bytes */
711 EMIT3(add_1mod(0x48, dst_reg), 0x0F,
712 add_1reg(0xC8, dst_reg));
713 break;
714 }
715 break;
716
717 case BPF_ALU | BPF_END | BPF_FROM_LE:
718 switch (imm32) {
719 case 16:
720 /* emit 'movzwl eax, ax' to zero extend 16-bit
721 * into 64 bit
722 */
723 if (is_ereg(dst_reg))
724 EMIT3(0x45, 0x0F, 0xB7);
725 else
726 EMIT2(0x0F, 0xB7);
727 EMIT1(add_2reg(0xC0, dst_reg, dst_reg));
728 break;
729 case 32:
730 /* emit 'mov eax, eax' to clear upper 32-bits */
731 if (is_ereg(dst_reg))
732 EMIT1(0x45);
733 EMIT2(0x89, add_2reg(0xC0, dst_reg, dst_reg));
734 break;
735 case 64:
736 /* nop */
737 break;
738 }
739 break;
740
741 /* ST: *(u8*)(dst_reg + off) = imm */
742 case BPF_ST | BPF_MEM | BPF_B:
743 if (is_ereg(dst_reg))
744 EMIT2(0x41, 0xC6);
745 else
746 EMIT1(0xC6);
747 goto st;
748 case BPF_ST | BPF_MEM | BPF_H:
749 if (is_ereg(dst_reg))
750 EMIT3(0x66, 0x41, 0xC7);
751 else
752 EMIT2(0x66, 0xC7);
753 goto st;
754 case BPF_ST | BPF_MEM | BPF_W:
755 if (is_ereg(dst_reg))
756 EMIT2(0x41, 0xC7);
757 else
758 EMIT1(0xC7);
759 goto st;
760 case BPF_ST | BPF_MEM | BPF_DW:
761 EMIT2(add_1mod(0x48, dst_reg), 0xC7);
762
763 st: if (is_imm8(insn->off))
764 EMIT2(add_1reg(0x40, dst_reg), insn->off);
765 else
766 EMIT1_off32(add_1reg(0x80, dst_reg), insn->off);
767
768 EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(insn->code)));
769 break;
770
771 /* STX: *(u8*)(dst_reg + off) = src_reg */
772 case BPF_STX | BPF_MEM | BPF_B:
773 /* emit 'mov byte ptr [rax + off], al' */
774 if (is_ereg(dst_reg) || is_ereg(src_reg) ||
775 /* have to add extra byte for x86 SIL, DIL regs */
776 src_reg == BPF_REG_1 || src_reg == BPF_REG_2)
777 EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x88);
778 else
779 EMIT1(0x88);
780 goto stx;
781 case BPF_STX | BPF_MEM | BPF_H:
782 if (is_ereg(dst_reg) || is_ereg(src_reg))
783 EMIT3(0x66, add_2mod(0x40, dst_reg, src_reg), 0x89);
784 else
785 EMIT2(0x66, 0x89);
786 goto stx;
787 case BPF_STX | BPF_MEM | BPF_W:
788 if (is_ereg(dst_reg) || is_ereg(src_reg))
789 EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x89);
790 else
791 EMIT1(0x89);
792 goto stx;
793 case BPF_STX | BPF_MEM | BPF_DW:
794 EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89);
795 stx: if (is_imm8(insn->off))
796 EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off);
797 else
798 EMIT1_off32(add_2reg(0x80, dst_reg, src_reg),
799 insn->off);
800 break;
801
802 /* LDX: dst_reg = *(u8*)(src_reg + off) */
803 case BPF_LDX | BPF_MEM | BPF_B:
804 /* emit 'movzx rax, byte ptr [rax + off]' */
805 EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB6);
806 goto ldx;
807 case BPF_LDX | BPF_MEM | BPF_H:
808 /* emit 'movzx rax, word ptr [rax + off]' */
809 EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB7);
810 goto ldx;
811 case BPF_LDX | BPF_MEM | BPF_W:
812 /* emit 'mov eax, dword ptr [rax+0x14]' */
813 if (is_ereg(dst_reg) || is_ereg(src_reg))
814 EMIT2(add_2mod(0x40, src_reg, dst_reg), 0x8B);
815 else
816 EMIT1(0x8B);
817 goto ldx;
818 case BPF_LDX | BPF_MEM | BPF_DW:
819 /* emit 'mov rax, qword ptr [rax+0x14]' */
820 EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B);
821 ldx: /* if insn->off == 0 we can save one extra byte, but
822 * special case of x86 r13 which always needs an offset
823 * is not worth the hassle
824 */
825 if (is_imm8(insn->off))
826 EMIT2(add_2reg(0x40, src_reg, dst_reg), insn->off);
827 else
828 EMIT1_off32(add_2reg(0x80, src_reg, dst_reg),
829 insn->off);
830 break;
831
832 /* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */
833 case BPF_STX | BPF_XADD | BPF_W:
834 /* emit 'lock add dword ptr [rax + off], eax' */
835 if (is_ereg(dst_reg) || is_ereg(src_reg))
836 EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01);
837 else
838 EMIT2(0xF0, 0x01);
839 goto xadd;
840 case BPF_STX | BPF_XADD | BPF_DW:
841 EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01);
842 xadd: if (is_imm8(insn->off))
843 EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off);
844 else
845 EMIT1_off32(add_2reg(0x80, dst_reg, src_reg),
846 insn->off);
847 break;
848
849 /* call */
850 case BPF_JMP | BPF_CALL:
851 func = (u8 *) __bpf_call_base + imm32;
852 jmp_offset = func - (image + addrs[i]);
853 if (seen_ld_abs) {
854 reload_skb_data = bpf_helper_changes_pkt_data(func);
855 if (reload_skb_data) {
856 EMIT1(0x57); /* push %rdi */
857 jmp_offset += 22; /* pop, mov, sub, mov */
858 } else {
859 EMIT2(0x41, 0x52); /* push %r10 */
860 EMIT2(0x41, 0x51); /* push %r9 */
861 /* need to adjust jmp offset, since
862 * pop %r9, pop %r10 take 4 bytes after call insn
863 */
864 jmp_offset += 4;
865 }
866 }
867 if (!imm32 || !is_simm32(jmp_offset)) {
868 pr_err("unsupported bpf func %d addr %p image %p\n",
869 imm32, func, image);
870 return -EINVAL;
871 }
872 EMIT1_off32(0xE8, jmp_offset);
873 if (seen_ld_abs) {
874 if (reload_skb_data) {
875 EMIT1(0x5F); /* pop %rdi */
876 emit_load_skb_data_hlen(&prog);
877 } else {
878 EMIT2(0x41, 0x59); /* pop %r9 */
879 EMIT2(0x41, 0x5A); /* pop %r10 */
880 }
881 }
882 break;
883
884 case BPF_JMP | BPF_TAIL_CALL:
885 emit_bpf_tail_call(&prog);
886 break;
887
888 /* cond jump */
889 case BPF_JMP | BPF_JEQ | BPF_X:
890 case BPF_JMP | BPF_JNE | BPF_X:
891 case BPF_JMP | BPF_JGT | BPF_X:
892 case BPF_JMP | BPF_JLT | BPF_X:
893 case BPF_JMP | BPF_JGE | BPF_X:
894 case BPF_JMP | BPF_JLE | BPF_X:
895 case BPF_JMP | BPF_JSGT | BPF_X:
896 case BPF_JMP | BPF_JSLT | BPF_X:
897 case BPF_JMP | BPF_JSGE | BPF_X:
898 case BPF_JMP | BPF_JSLE | BPF_X:
899 /* cmp dst_reg, src_reg */
900 EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x39,
901 add_2reg(0xC0, dst_reg, src_reg));
902 goto emit_cond_jmp;
903
904 case BPF_JMP | BPF_JSET | BPF_X:
905 /* test dst_reg, src_reg */
906 EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x85,
907 add_2reg(0xC0, dst_reg, src_reg));
908 goto emit_cond_jmp;
909
910 case BPF_JMP | BPF_JSET | BPF_K:
911 /* test dst_reg, imm32 */
912 EMIT1(add_1mod(0x48, dst_reg));
913 EMIT2_off32(0xF7, add_1reg(0xC0, dst_reg), imm32);
914 goto emit_cond_jmp;
915
916 case BPF_JMP | BPF_JEQ | BPF_K:
917 case BPF_JMP | BPF_JNE | BPF_K:
918 case BPF_JMP | BPF_JGT | BPF_K:
919 case BPF_JMP | BPF_JLT | BPF_K:
920 case BPF_JMP | BPF_JGE | BPF_K:
921 case BPF_JMP | BPF_JLE | BPF_K:
922 case BPF_JMP | BPF_JSGT | BPF_K:
923 case BPF_JMP | BPF_JSLT | BPF_K:
924 case BPF_JMP | BPF_JSGE | BPF_K:
925 case BPF_JMP | BPF_JSLE | BPF_K:
926 /* cmp dst_reg, imm8/32 */
927 EMIT1(add_1mod(0x48, dst_reg));
928
929 if (is_imm8(imm32))
930 EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32);
931 else
932 EMIT2_off32(0x81, add_1reg(0xF8, dst_reg), imm32);
933
934 emit_cond_jmp: /* convert BPF opcode to x86 */
935 switch (BPF_OP(insn->code)) {
936 case BPF_JEQ:
937 jmp_cond = X86_JE;
938 break;
939 case BPF_JSET:
940 case BPF_JNE:
941 jmp_cond = X86_JNE;
942 break;
943 case BPF_JGT:
944 /* GT is unsigned '>', JA in x86 */
945 jmp_cond = X86_JA;
946 break;
947 case BPF_JLT:
948 /* LT is unsigned '<', JB in x86 */
949 jmp_cond = X86_JB;
950 break;
951 case BPF_JGE:
952 /* GE is unsigned '>=', JAE in x86 */
953 jmp_cond = X86_JAE;
954 break;
955 case BPF_JLE:
956 /* LE is unsigned '<=', JBE in x86 */
957 jmp_cond = X86_JBE;
958 break;
959 case BPF_JSGT:
960 /* signed '>', GT in x86 */
961 jmp_cond = X86_JG;
962 break;
963 case BPF_JSLT:
964 /* signed '<', LT in x86 */
965 jmp_cond = X86_JL;
966 break;
967 case BPF_JSGE:
968 /* signed '>=', GE in x86 */
969 jmp_cond = X86_JGE;
970 break;
971 case BPF_JSLE:
972 /* signed '<=', LE in x86 */
973 jmp_cond = X86_JLE;
974 break;
975 default: /* to silence gcc warning */
976 return -EFAULT;
977 }
978 jmp_offset = addrs[i + insn->off] - addrs[i];
979 if (is_imm8(jmp_offset)) {
980 EMIT2(jmp_cond, jmp_offset);
981 } else if (is_simm32(jmp_offset)) {
982 EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset);
983 } else {
984 pr_err("cond_jmp gen bug %llx\n", jmp_offset);
985 return -EFAULT;
986 }
987
988 break;
989
990 case BPF_JMP | BPF_JA:
991 jmp_offset = addrs[i + insn->off] - addrs[i];
992 if (!jmp_offset)
993 /* optimize out nop jumps */
994 break;
995 emit_jmp:
996 if (is_imm8(jmp_offset)) {
997 EMIT2(0xEB, jmp_offset);
998 } else if (is_simm32(jmp_offset)) {
999 EMIT1_off32(0xE9, jmp_offset);
1000 } else {
1001 pr_err("jmp gen bug %llx\n", jmp_offset);
1002 return -EFAULT;
1003 }
1004 break;
1005
1006 case BPF_LD | BPF_IND | BPF_W:
1007 func = sk_load_word;
1008 goto common_load;
1009 case BPF_LD | BPF_ABS | BPF_W:
1010 func = CHOOSE_LOAD_FUNC(imm32, sk_load_word);
1011 common_load:
1012 ctx->seen_ld_abs = seen_ld_abs = true;
1013 jmp_offset = func - (image + addrs[i]);
1014 if (!func || !is_simm32(jmp_offset)) {
1015 pr_err("unsupported bpf func %d addr %p image %p\n",
1016 imm32, func, image);
1017 return -EINVAL;
1018 }
1019 if (BPF_MODE(insn->code) == BPF_ABS) {
1020 /* mov %esi, imm32 */
1021 EMIT1_off32(0xBE, imm32);
1022 } else {
1023 /* mov %rsi, src_reg */
1024 EMIT_mov(BPF_REG_2, src_reg);
1025 if (imm32) {
1026 if (is_imm8(imm32))
1027 /* add %esi, imm8 */
1028 EMIT3(0x83, 0xC6, imm32);
1029 else
1030 /* add %esi, imm32 */
1031 EMIT2_off32(0x81, 0xC6, imm32);
1032 }
1033 }
1034 /* skb pointer is in R6 (%rbx), it will be copied into
1035 * %rdi if skb_copy_bits() call is necessary.
1036 * sk_load_* helpers also use %r10 and %r9d.
1037 * See bpf_jit.S
1038 */
1039 if (seen_ax_reg)
1040 /* r10 = skb->data, mov %r10, off32(%rbx) */
1041 EMIT3_off32(0x4c, 0x8b, 0x93,
1042 offsetof(struct sk_buff, data));
1043 EMIT1_off32(0xE8, jmp_offset); /* call */
1044 break;
1045
1046 case BPF_LD | BPF_IND | BPF_H:
1047 func = sk_load_half;
1048 goto common_load;
1049 case BPF_LD | BPF_ABS | BPF_H:
1050 func = CHOOSE_LOAD_FUNC(imm32, sk_load_half);
1051 goto common_load;
1052 case BPF_LD | BPF_IND | BPF_B:
1053 func = sk_load_byte;
1054 goto common_load;
1055 case BPF_LD | BPF_ABS | BPF_B:
1056 func = CHOOSE_LOAD_FUNC(imm32, sk_load_byte);
1057 goto common_load;
1058
1059 case BPF_JMP | BPF_EXIT:
1060 if (seen_exit) {
1061 jmp_offset = ctx->cleanup_addr - addrs[i];
1062 goto emit_jmp;
1063 }
1064 seen_exit = true;
1065 /* update cleanup_addr */
1066 ctx->cleanup_addr = proglen;
1067 /* mov rbx, qword ptr [rbp+0] */
1068 EMIT4(0x48, 0x8B, 0x5D, 0);
1069 /* mov r13, qword ptr [rbp+8] */
1070 EMIT4(0x4C, 0x8B, 0x6D, 8);
1071 /* mov r14, qword ptr [rbp+16] */
1072 EMIT4(0x4C, 0x8B, 0x75, 16);
1073 /* mov r15, qword ptr [rbp+24] */
1074 EMIT4(0x4C, 0x8B, 0x7D, 24);
1075
1076 /* add rbp, AUX_STACK_SPACE */
1077 EMIT4(0x48, 0x83, 0xC5, AUX_STACK_SPACE);
1078 EMIT1(0xC9); /* leave */
1079 EMIT1(0xC3); /* ret */
1080 break;
1081
1082 default:
1083 /* By design x64 JIT should support all BPF instructions
1084 * This error will be seen if new instruction was added
1085 * to interpreter, but not to JIT
1086 * or if there is junk in bpf_prog
1087 */
1088 pr_err("bpf_jit: unknown opcode %02x\n", insn->code);
1089 return -EINVAL;
1090 }
1091
1092 ilen = prog - temp;
1093 if (ilen > BPF_MAX_INSN_SIZE) {
1094 pr_err("bpf_jit: fatal insn size error\n");
1095 return -EFAULT;
1096 }
1097
1098 if (image) {
1099 if (unlikely(proglen + ilen > oldproglen)) {
1100 pr_err("bpf_jit: fatal error\n");
1101 return -EFAULT;
1102 }
1103 memcpy(image + proglen, temp, ilen);
1104 }
1105 proglen += ilen;
1106 addrs[i] = proglen;
1107 prog = temp;
1108 }
1109 return proglen;
1110 }
1111
1112 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
1113 {
1114 struct bpf_binary_header *header = NULL;
1115 struct bpf_prog *tmp, *orig_prog = prog;
1116 int proglen, oldproglen = 0;
1117 struct jit_context ctx = {};
1118 bool tmp_blinded = false;
1119 u8 *image = NULL;
1120 int *addrs;
1121 int pass;
1122 int i;
1123
1124 if (!bpf_jit_enable)
1125 return orig_prog;
1126
1127 tmp = bpf_jit_blind_constants(prog);
1128 /* If blinding was requested and we failed during blinding,
1129 * we must fall back to the interpreter.
1130 */
1131 if (IS_ERR(tmp))
1132 return orig_prog;
1133 if (tmp != prog) {
1134 tmp_blinded = true;
1135 prog = tmp;
1136 }
1137
1138 addrs = kmalloc(prog->len * sizeof(*addrs), GFP_KERNEL);
1139 if (!addrs) {
1140 prog = orig_prog;
1141 goto out;
1142 }
1143
1144 /* Before first pass, make a rough estimation of addrs[]
1145 * each bpf instruction is translated to less than 64 bytes
1146 */
1147 for (proglen = 0, i = 0; i < prog->len; i++) {
1148 proglen += 64;
1149 addrs[i] = proglen;
1150 }
1151 ctx.cleanup_addr = proglen;
1152
1153 /* JITed image shrinks with every pass and the loop iterates
1154 * until the image stops shrinking. Very large bpf programs
1155 * may converge on the last pass. In such case do one more
1156 * pass to emit the final image
1157 */
1158 for (pass = 0; pass < 10 || image; pass++) {
1159 proglen = do_jit(prog, addrs, image, oldproglen, &ctx);
1160 if (proglen <= 0) {
1161 image = NULL;
1162 if (header)
1163 bpf_jit_binary_free(header);
1164 prog = orig_prog;
1165 goto out_addrs;
1166 }
1167 if (image) {
1168 if (proglen != oldproglen) {
1169 pr_err("bpf_jit: proglen=%d != oldproglen=%d\n",
1170 proglen, oldproglen);
1171 prog = orig_prog;
1172 goto out_addrs;
1173 }
1174 break;
1175 }
1176 if (proglen == oldproglen) {
1177 header = bpf_jit_binary_alloc(proglen, &image,
1178 1, jit_fill_hole);
1179 if (!header) {
1180 prog = orig_prog;
1181 goto out_addrs;
1182 }
1183 }
1184 oldproglen = proglen;
1185 }
1186
1187 if (bpf_jit_enable > 1)
1188 bpf_jit_dump(prog->len, proglen, pass + 1, image);
1189
1190 if (image) {
1191 bpf_flush_icache(header, image + proglen);
1192 bpf_jit_binary_lock_ro(header);
1193 prog->bpf_func = (void *)image;
1194 prog->jited = 1;
1195 prog->jited_len = proglen;
1196 } else {
1197 prog = orig_prog;
1198 }
1199
1200 out_addrs:
1201 kfree(addrs);
1202 out:
1203 if (tmp_blinded)
1204 bpf_jit_prog_release_other(prog, prog == orig_prog ?
1205 tmp : orig_prog);
1206 return prog;
1207 }
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