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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 | // SPDX-License-Identifier: GPL-2.0 #include <linux/workqueue.h> #include <linux/netdevice.h> #include <linux/filter.h> #include <linux/cache.h> #include <linux/if_vlan.h> #include <linux/execmem.h> #include <asm/cacheflush.h> #include <asm/ptrace.h> #include "bpf_jit_32.h" static inline bool is_simm13(unsigned int value) { return value + 0x1000 < 0x2000; } #define SEEN_DATAREF 1 /* might call external helpers */ #define SEEN_XREG 2 /* ebx is used */ #define SEEN_MEM 4 /* use mem[] for temporary storage */ #define S13(X) ((X) & 0x1fff) #define IMMED 0x00002000 #define RD(X) ((X) << 25) #define RS1(X) ((X) << 14) #define RS2(X) ((X)) #define OP(X) ((X) << 30) #define OP2(X) ((X) << 22) #define OP3(X) ((X) << 19) #define COND(X) ((X) << 25) #define F1(X) OP(X) #define F2(X, Y) (OP(X) | OP2(Y)) #define F3(X, Y) (OP(X) | OP3(Y)) #define CONDN COND(0x0) #define CONDE COND(0x1) #define CONDLE COND(0x2) #define CONDL COND(0x3) #define CONDLEU COND(0x4) #define CONDCS COND(0x5) #define CONDNEG COND(0x6) #define CONDVC COND(0x7) #define CONDA COND(0x8) #define CONDNE COND(0x9) #define CONDG COND(0xa) #define CONDGE COND(0xb) #define CONDGU COND(0xc) #define CONDCC COND(0xd) #define CONDPOS COND(0xe) #define CONDVS COND(0xf) #define CONDGEU CONDCC #define CONDLU CONDCS #define WDISP22(X) (((X) >> 2) & 0x3fffff) #define BA (F2(0, 2) | CONDA) #define BGU (F2(0, 2) | CONDGU) #define BLEU (F2(0, 2) | CONDLEU) #define BGEU (F2(0, 2) | CONDGEU) #define BLU (F2(0, 2) | CONDLU) #define BE (F2(0, 2) | CONDE) #define BNE (F2(0, 2) | CONDNE) #define BE_PTR BE #define SETHI(K, REG) \ (F2(0, 0x4) | RD(REG) | (((K) >> 10) & 0x3fffff)) #define OR_LO(K, REG) \ (F3(2, 0x02) | IMMED | RS1(REG) | ((K) & 0x3ff) | RD(REG)) #define ADD F3(2, 0x00) #define AND F3(2, 0x01) #define ANDCC F3(2, 0x11) #define OR F3(2, 0x02) #define XOR F3(2, 0x03) #define SUB F3(2, 0x04) #define SUBCC F3(2, 0x14) #define MUL F3(2, 0x0a) /* umul */ #define DIV F3(2, 0x0e) /* udiv */ #define SLL F3(2, 0x25) #define SRL F3(2, 0x26) #define JMPL F3(2, 0x38) #define CALL F1(1) #define BR F2(0, 0x01) #define RD_Y F3(2, 0x28) #define WR_Y F3(2, 0x30) #define LD32 F3(3, 0x00) #define LD8 F3(3, 0x01) #define LD16 F3(3, 0x02) #define LD64 F3(3, 0x0b) #define ST32 F3(3, 0x04) #define LDPTR LD32 #define BASE_STACKFRAME 96 #define LD32I (LD32 | IMMED) #define LD8I (LD8 | IMMED) #define LD16I (LD16 | IMMED) #define LD64I (LD64 | IMMED) #define LDPTRI (LDPTR | IMMED) #define ST32I (ST32 | IMMED) #define emit_nop() \ do { \ *prog++ = SETHI(0, G0); \ } while (0) #define emit_neg() \ do { /* sub %g0, r_A, r_A */ \ *prog++ = SUB | RS1(G0) | RS2(r_A) | RD(r_A); \ } while (0) #define emit_reg_move(FROM, TO) \ do { /* or %g0, FROM, TO */ \ *prog++ = OR | RS1(G0) | RS2(FROM) | RD(TO); \ } while (0) #define emit_clear(REG) \ do { /* or %g0, %g0, REG */ \ *prog++ = OR | RS1(G0) | RS2(G0) | RD(REG); \ } while (0) #define emit_set_const(K, REG) \ do { /* sethi %hi(K), REG */ \ *prog++ = SETHI(K, REG); \ /* or REG, %lo(K), REG */ \ *prog++ = OR_LO(K, REG); \ } while (0) /* Emit * * OP r_A, r_X, r_A */ #define emit_alu_X(OPCODE) \ do { \ seen |= SEEN_XREG; \ *prog++ = OPCODE | RS1(r_A) | RS2(r_X) | RD(r_A); \ } while (0) /* Emit either: * * OP r_A, K, r_A * * or * * sethi %hi(K), r_TMP * or r_TMP, %lo(K), r_TMP * OP r_A, r_TMP, r_A * * depending upon whether K fits in a signed 13-bit * immediate instruction field. Emit nothing if K * is zero. */ #define emit_alu_K(OPCODE, K) \ do { \ if (K || OPCODE == AND || OPCODE == MUL) { \ unsigned int _insn = OPCODE; \ _insn |= RS1(r_A) | RD(r_A); \ if (is_simm13(K)) { \ *prog++ = _insn | IMMED | S13(K); \ } else { \ emit_set_const(K, r_TMP); \ *prog++ = _insn | RS2(r_TMP); \ } \ } \ } while (0) #define emit_loadimm(K, DEST) \ do { \ if (is_simm13(K)) { \ /* or %g0, K, DEST */ \ *prog++ = OR | IMMED | RS1(G0) | S13(K) | RD(DEST); \ } else { \ emit_set_const(K, DEST); \ } \ } while (0) #define emit_loadptr(BASE, STRUCT, FIELD, DEST) \ do { unsigned int _off = offsetof(STRUCT, FIELD); \ BUILD_BUG_ON(sizeof_field(STRUCT, FIELD) != sizeof(void *)); \ *prog++ = LDPTRI | RS1(BASE) | S13(_off) | RD(DEST); \ } while (0) #define emit_load32(BASE, STRUCT, FIELD, DEST) \ do { unsigned int _off = offsetof(STRUCT, FIELD); \ BUILD_BUG_ON(sizeof_field(STRUCT, FIELD) != sizeof(u32)); \ *prog++ = LD32I | RS1(BASE) | S13(_off) | RD(DEST); \ } while (0) #define emit_load16(BASE, STRUCT, FIELD, DEST) \ do { unsigned int _off = offsetof(STRUCT, FIELD); \ BUILD_BUG_ON(sizeof_field(STRUCT, FIELD) != sizeof(u16)); \ *prog++ = LD16I | RS1(BASE) | S13(_off) | RD(DEST); \ } while (0) #define __emit_load8(BASE, STRUCT, FIELD, DEST) \ do { unsigned int _off = offsetof(STRUCT, FIELD); \ *prog++ = LD8I | RS1(BASE) | S13(_off) | RD(DEST); \ } while (0) #define emit_load8(BASE, STRUCT, FIELD, DEST) \ do { BUILD_BUG_ON(sizeof_field(STRUCT, FIELD) != sizeof(u8)); \ __emit_load8(BASE, STRUCT, FIELD, DEST); \ } while (0) #define BIAS (-4) #define emit_ldmem(OFF, DEST) \ do { *prog++ = LD32I | RS1(SP) | S13(BIAS - (OFF)) | RD(DEST); \ } while (0) #define emit_stmem(OFF, SRC) \ do { *prog++ = ST32I | RS1(SP) | S13(BIAS - (OFF)) | RD(SRC); \ } while (0) #ifdef CONFIG_SMP #define emit_load_cpu(REG) \ emit_load32(G6, struct thread_info, cpu, REG) #else #define emit_load_cpu(REG) emit_clear(REG) #endif #define emit_skb_loadptr(FIELD, DEST) \ emit_loadptr(r_SKB, struct sk_buff, FIELD, DEST) #define emit_skb_load32(FIELD, DEST) \ emit_load32(r_SKB, struct sk_buff, FIELD, DEST) #define emit_skb_load16(FIELD, DEST) \ emit_load16(r_SKB, struct sk_buff, FIELD, DEST) #define __emit_skb_load8(FIELD, DEST) \ __emit_load8(r_SKB, struct sk_buff, FIELD, DEST) #define emit_skb_load8(FIELD, DEST) \ emit_load8(r_SKB, struct sk_buff, FIELD, DEST) #define emit_jmpl(BASE, IMM_OFF, LREG) \ *prog++ = (JMPL | IMMED | RS1(BASE) | S13(IMM_OFF) | RD(LREG)) #define emit_call(FUNC) \ do { void *_here = image + addrs[i] - 8; \ unsigned int _off = (void *)(FUNC) - _here; \ *prog++ = CALL | (((_off) >> 2) & 0x3fffffff); \ emit_nop(); \ } while (0) #define emit_branch(BR_OPC, DEST) \ do { unsigned int _here = addrs[i] - 8; \ *prog++ = BR_OPC | WDISP22((DEST) - _here); \ } while (0) #define emit_branch_off(BR_OPC, OFF) \ do { *prog++ = BR_OPC | WDISP22(OFF); \ } while (0) #define emit_jump(DEST) emit_branch(BA, DEST) #define emit_read_y(REG) *prog++ = RD_Y | RD(REG) #define emit_write_y(REG) *prog++ = WR_Y | IMMED | RS1(REG) | S13(0) #define emit_cmp(R1, R2) \ *prog++ = (SUBCC | RS1(R1) | RS2(R2) | RD(G0)) #define emit_cmpi(R1, IMM) \ *prog++ = (SUBCC | IMMED | RS1(R1) | S13(IMM) | RD(G0)); #define emit_btst(R1, R2) \ *prog++ = (ANDCC | RS1(R1) | RS2(R2) | RD(G0)) #define emit_btsti(R1, IMM) \ *prog++ = (ANDCC | IMMED | RS1(R1) | S13(IMM) | RD(G0)); #define emit_sub(R1, R2, R3) \ *prog++ = (SUB | RS1(R1) | RS2(R2) | RD(R3)) #define emit_subi(R1, IMM, R3) \ *prog++ = (SUB | IMMED | RS1(R1) | S13(IMM) | RD(R3)) #define emit_add(R1, R2, R3) \ *prog++ = (ADD | RS1(R1) | RS2(R2) | RD(R3)) #define emit_addi(R1, IMM, R3) \ *prog++ = (ADD | IMMED | RS1(R1) | S13(IMM) | RD(R3)) #define emit_and(R1, R2, R3) \ *prog++ = (AND | RS1(R1) | RS2(R2) | RD(R3)) #define emit_andi(R1, IMM, R3) \ *prog++ = (AND | IMMED | RS1(R1) | S13(IMM) | RD(R3)) #define emit_alloc_stack(SZ) \ *prog++ = (SUB | IMMED | RS1(SP) | S13(SZ) | RD(SP)) #define emit_release_stack(SZ) \ *prog++ = (ADD | IMMED | RS1(SP) | S13(SZ) | RD(SP)) /* A note about branch offset calculations. The addrs[] array, * indexed by BPF instruction, records the address after all the * sparc instructions emitted for that BPF instruction. * * The most common case is to emit a branch at the end of such * a code sequence. So this would be two instructions, the * branch and its delay slot. * * Therefore by default the branch emitters calculate the branch * offset field as: * * destination - (addrs[i] - 8) * * This "addrs[i] - 8" is the address of the branch itself or * what "." would be in assembler notation. The "8" part is * how we take into consideration the branch and its delay * slot mentioned above. * * Sometimes we need to emit a branch earlier in the code * sequence. And in these situations we adjust "destination" * to accommodate this difference. For example, if we needed * to emit a branch (and its delay slot) right before the * final instruction emitted for a BPF opcode, we'd use * "destination + 4" instead of just plain "destination" above. * * This is why you see all of these funny emit_branch() and * emit_jump() calls with adjusted offsets. */ void bpf_jit_compile(struct bpf_prog *fp) { unsigned int cleanup_addr, proglen, oldproglen = 0; u32 temp[8], *prog, *func, seen = 0, pass; const struct sock_filter *filter = fp->insns; int i, flen = fp->len, pc_ret0 = -1; unsigned int *addrs; void *image; if (!bpf_jit_enable) return; addrs = kmalloc_array(flen, sizeof(*addrs), GFP_KERNEL); if (addrs == NULL) return; /* Before first pass, make a rough estimation of addrs[] * each bpf instruction is translated to less than 64 bytes */ for (proglen = 0, i = 0; i < flen; i++) { proglen += 64; addrs[i] = proglen; } cleanup_addr = proglen; /* epilogue address */ image = NULL; for (pass = 0; pass < 10; pass++) { u8 seen_or_pass0 = (pass == 0) ? (SEEN_XREG | SEEN_DATAREF | SEEN_MEM) : seen; /* no prologue/epilogue for trivial filters (RET something) */ proglen = 0; prog = temp; /* Prologue */ if (seen_or_pass0) { if (seen_or_pass0 & SEEN_MEM) { unsigned int sz = BASE_STACKFRAME; sz += BPF_MEMWORDS * sizeof(u32); emit_alloc_stack(sz); } /* Make sure we dont leek kernel memory. */ if (seen_or_pass0 & SEEN_XREG) emit_clear(r_X); /* If this filter needs to access skb data, * load %o4 and %o5 with: * %o4 = skb->len - skb->data_len * %o5 = skb->data * And also back up %o7 into r_saved_O7 so we can * invoke the stubs using 'call'. */ if (seen_or_pass0 & SEEN_DATAREF) { emit_load32(r_SKB, struct sk_buff, len, r_HEADLEN); emit_load32(r_SKB, struct sk_buff, data_len, r_TMP); emit_sub(r_HEADLEN, r_TMP, r_HEADLEN); emit_loadptr(r_SKB, struct sk_buff, data, r_SKB_DATA); } } emit_reg_move(O7, r_saved_O7); /* Make sure we dont leak kernel information to the user. */ if (bpf_needs_clear_a(&filter[0])) emit_clear(r_A); /* A = 0 */ for (i = 0; i < flen; i++) { unsigned int K = filter[i].k; unsigned int t_offset; unsigned int f_offset; u32 t_op, f_op; u16 code = bpf_anc_helper(&filter[i]); int ilen; switch (code) { case BPF_ALU | BPF_ADD | BPF_X: /* A += X; */ emit_alu_X(ADD); break; case BPF_ALU | BPF_ADD | BPF_K: /* A += K; */ emit_alu_K(ADD, K); break; case BPF_ALU | BPF_SUB | BPF_X: /* A -= X; */ emit_alu_X(SUB); break; case BPF_ALU | BPF_SUB | BPF_K: /* A -= K */ emit_alu_K(SUB, K); break; case BPF_ALU | BPF_AND | BPF_X: /* A &= X */ emit_alu_X(AND); break; case BPF_ALU | BPF_AND | BPF_K: /* A &= K */ emit_alu_K(AND, K); break; case BPF_ALU | BPF_OR | BPF_X: /* A |= X */ emit_alu_X(OR); break; case BPF_ALU | BPF_OR | BPF_K: /* A |= K */ emit_alu_K(OR, K); break; case BPF_ANC | SKF_AD_ALU_XOR_X: /* A ^= X; */ case BPF_ALU | BPF_XOR | BPF_X: emit_alu_X(XOR); break; case BPF_ALU | BPF_XOR | BPF_K: /* A ^= K */ emit_alu_K(XOR, K); break; case BPF_ALU | BPF_LSH | BPF_X: /* A <<= X */ emit_alu_X(SLL); break; case BPF_ALU | BPF_LSH | BPF_K: /* A <<= K */ emit_alu_K(SLL, K); break; case BPF_ALU | BPF_RSH | BPF_X: /* A >>= X */ emit_alu_X(SRL); break; case BPF_ALU | BPF_RSH | BPF_K: /* A >>= K */ emit_alu_K(SRL, K); break; case BPF_ALU | BPF_MUL | BPF_X: /* A *= X; */ emit_alu_X(MUL); break; case BPF_ALU | BPF_MUL | BPF_K: /* A *= K */ emit_alu_K(MUL, K); break; case BPF_ALU | BPF_DIV | BPF_K: /* A /= K with K != 0*/ if (K == 1) break; emit_write_y(G0); /* The Sparc v8 architecture requires * three instructions between a %y * register write and the first use. */ emit_nop(); emit_nop(); emit_nop(); emit_alu_K(DIV, K); break; case BPF_ALU | BPF_DIV | BPF_X: /* A /= X; */ emit_cmpi(r_X, 0); if (pc_ret0 > 0) { t_offset = addrs[pc_ret0 - 1]; emit_branch(BE, t_offset + 20); emit_nop(); /* delay slot */ } else { emit_branch_off(BNE, 16); emit_nop(); emit_jump(cleanup_addr + 20); emit_clear(r_A); } emit_write_y(G0); /* The Sparc v8 architecture requires * three instructions between a %y * register write and the first use. */ emit_nop(); emit_nop(); emit_nop(); emit_alu_X(DIV); break; case BPF_ALU | BPF_NEG: emit_neg(); break; case BPF_RET | BPF_K: if (!K) { if (pc_ret0 == -1) pc_ret0 = i; emit_clear(r_A); } else { emit_loadimm(K, r_A); } fallthrough; case BPF_RET | BPF_A: if (seen_or_pass0) { if (i != flen - 1) { emit_jump(cleanup_addr); emit_nop(); break; } if (seen_or_pass0 & SEEN_MEM) { unsigned int sz = BASE_STACKFRAME; sz += BPF_MEMWORDS * sizeof(u32); emit_release_stack(sz); } } /* jmpl %r_saved_O7 + 8, %g0 */ emit_jmpl(r_saved_O7, 8, G0); emit_reg_move(r_A, O0); /* delay slot */ break; case BPF_MISC | BPF_TAX: seen |= SEEN_XREG; emit_reg_move(r_A, r_X); break; case BPF_MISC | BPF_TXA: seen |= SEEN_XREG; emit_reg_move(r_X, r_A); break; case BPF_ANC | SKF_AD_CPU: emit_load_cpu(r_A); break; case BPF_ANC | SKF_AD_PROTOCOL: emit_skb_load16(protocol, r_A); break; case BPF_ANC | SKF_AD_PKTTYPE: __emit_skb_load8(__pkt_type_offset, r_A); emit_andi(r_A, PKT_TYPE_MAX, r_A); emit_alu_K(SRL, 5); break; case BPF_ANC | SKF_AD_IFINDEX: emit_skb_loadptr(dev, r_A); emit_cmpi(r_A, 0); emit_branch(BE_PTR, cleanup_addr + 4); emit_nop(); emit_load32(r_A, struct net_device, ifindex, r_A); break; case BPF_ANC | SKF_AD_MARK: emit_skb_load32(mark, r_A); break; case BPF_ANC | SKF_AD_QUEUE: emit_skb_load16(queue_mapping, r_A); break; case BPF_ANC | SKF_AD_HATYPE: emit_skb_loadptr(dev, r_A); emit_cmpi(r_A, 0); emit_branch(BE_PTR, cleanup_addr + 4); emit_nop(); emit_load16(r_A, struct net_device, type, r_A); break; case BPF_ANC | SKF_AD_RXHASH: emit_skb_load32(hash, r_A); break; case BPF_ANC | SKF_AD_VLAN_TAG: emit_skb_load16(vlan_tci, r_A); break; case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT: emit_skb_load32(vlan_all, r_A); emit_cmpi(r_A, 0); emit_branch_off(BE, 12); emit_nop(); emit_loadimm(1, r_A); break; case BPF_LD | BPF_W | BPF_LEN: emit_skb_load32(len, r_A); break; case BPF_LDX | BPF_W | BPF_LEN: emit_skb_load32(len, r_X); break; case BPF_LD | BPF_IMM: emit_loadimm(K, r_A); break; case BPF_LDX | BPF_IMM: emit_loadimm(K, r_X); break; case BPF_LD | BPF_MEM: seen |= SEEN_MEM; emit_ldmem(K * 4, r_A); break; case BPF_LDX | BPF_MEM: seen |= SEEN_MEM | SEEN_XREG; emit_ldmem(K * 4, r_X); break; case BPF_ST: seen |= SEEN_MEM; emit_stmem(K * 4, r_A); break; case BPF_STX: seen |= SEEN_MEM | SEEN_XREG; emit_stmem(K * 4, r_X); break; #define CHOOSE_LOAD_FUNC(K, func) \ ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) case BPF_LD | BPF_W | BPF_ABS: func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_word); common_load: seen |= SEEN_DATAREF; emit_loadimm(K, r_OFF); emit_call(func); break; case BPF_LD | BPF_H | BPF_ABS: func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_half); goto common_load; case BPF_LD | BPF_B | BPF_ABS: func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte); goto common_load; case BPF_LDX | BPF_B | BPF_MSH: func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte_msh); goto common_load; case BPF_LD | BPF_W | BPF_IND: func = bpf_jit_load_word; common_load_ind: seen |= SEEN_DATAREF | SEEN_XREG; if (K) { if (is_simm13(K)) { emit_addi(r_X, K, r_OFF); } else { emit_loadimm(K, r_TMP); emit_add(r_X, r_TMP, r_OFF); } } else { emit_reg_move(r_X, r_OFF); } emit_call(func); break; case BPF_LD | BPF_H | BPF_IND: func = bpf_jit_load_half; goto common_load_ind; case BPF_LD | BPF_B | BPF_IND: func = bpf_jit_load_byte; goto common_load_ind; case BPF_JMP | BPF_JA: emit_jump(addrs[i + K]); emit_nop(); break; #define COND_SEL(CODE, TOP, FOP) \ case CODE: \ t_op = TOP; \ f_op = FOP; \ goto cond_branch COND_SEL(BPF_JMP | BPF_JGT | BPF_K, BGU, BLEU); COND_SEL(BPF_JMP | BPF_JGE | BPF_K, BGEU, BLU); COND_SEL(BPF_JMP | BPF_JEQ | BPF_K, BE, BNE); COND_SEL(BPF_JMP | BPF_JSET | BPF_K, BNE, BE); COND_SEL(BPF_JMP | BPF_JGT | BPF_X, BGU, BLEU); COND_SEL(BPF_JMP | BPF_JGE | BPF_X, BGEU, BLU); COND_SEL(BPF_JMP | BPF_JEQ | BPF_X, BE, BNE); COND_SEL(BPF_JMP | BPF_JSET | BPF_X, BNE, BE); cond_branch: f_offset = addrs[i + filter[i].jf]; t_offset = addrs[i + filter[i].jt]; /* same targets, can avoid doing the test :) */ if (filter[i].jt == filter[i].jf) { emit_jump(t_offset); emit_nop(); break; } switch (code) { case BPF_JMP | BPF_JGT | BPF_X: case BPF_JMP | BPF_JGE | BPF_X: case BPF_JMP | BPF_JEQ | BPF_X: seen |= SEEN_XREG; emit_cmp(r_A, r_X); break; case BPF_JMP | BPF_JSET | BPF_X: seen |= SEEN_XREG; emit_btst(r_A, r_X); break; case BPF_JMP | BPF_JEQ | BPF_K: case BPF_JMP | BPF_JGT | BPF_K: case BPF_JMP | BPF_JGE | BPF_K: if (is_simm13(K)) { emit_cmpi(r_A, K); } else { emit_loadimm(K, r_TMP); emit_cmp(r_A, r_TMP); } break; case BPF_JMP | BPF_JSET | BPF_K: if (is_simm13(K)) { emit_btsti(r_A, K); } else { emit_loadimm(K, r_TMP); emit_btst(r_A, r_TMP); } break; } if (filter[i].jt != 0) { if (filter[i].jf) t_offset += 8; emit_branch(t_op, t_offset); emit_nop(); /* delay slot */ if (filter[i].jf) { emit_jump(f_offset); emit_nop(); } break; } emit_branch(f_op, f_offset); emit_nop(); /* delay slot */ break; default: /* hmm, too complex filter, give up with jit compiler */ goto out; } ilen = (void *) prog - (void *) temp; if (image) { if (unlikely(proglen + ilen > oldproglen)) { pr_err("bpb_jit_compile fatal error\n"); kfree(addrs); execmem_free(image); return; } memcpy(image + proglen, temp, ilen); } proglen += ilen; addrs[i] = proglen; prog = temp; } /* last bpf instruction is always a RET : * use it to give the cleanup instruction(s) addr */ cleanup_addr = proglen - 8; /* jmpl; mov r_A,%o0; */ if (seen_or_pass0 & SEEN_MEM) cleanup_addr -= 4; /* add %sp, X, %sp; */ if (image) { if (proglen != oldproglen) pr_err("bpb_jit_compile proglen=%u != oldproglen=%u\n", proglen, oldproglen); break; } if (proglen == oldproglen) { image = execmem_alloc(EXECMEM_BPF, proglen); if (!image) goto out; } oldproglen = proglen; } if (bpf_jit_enable > 1) bpf_jit_dump(flen, proglen, pass + 1, image); if (image) { fp->bpf_func = (void *)image; fp->jited = 1; } out: kfree(addrs); return; } void bpf_jit_free(struct bpf_prog *fp) { if (fp->jited) execmem_free(fp->bpf_func); bpf_prog_unlock_free(fp); } |