DF-2664 / lz4_zero_input_fixed.c
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 | /* * DF-2664 — LZ4_decompress_safe() 1-byte OOB source read when inputSize==0 * + margin-discipline fuzz (negative proof for the rest of the * decoder on LP64). * * TARGET CODE (verbatim excerpt): sys/vfs/hammer2/hammer2_lz4.c:372-525 * The decompressor compiled here is byte-for-byte the logic of the in-tree * hammer2 LZ4 (upstream LZ4 r97, 2013-06-10) — same macros, same checks, * LZ4_ARCH64=1 (x86-64, the only DragonFly platform: pc64/vkernel64). * * TEST A (the finding): * LZ4_decompress_safe(source, dest, 0, outSize) — the very first * statement of the main loop is `token = *ip++;` * (hammer2_lz4.c:418) with NO preceding `ip < iend` check; the only * pre-loop guard is `outputSize==0` (hammer2_lz4.c:407). With * inputSize==0, iend==source, so the token fetch dereferences * source[0] — one byte past the declared input buffer. * * Proof layout: [ RW page | PROT_NONE guard ]; source = END of the RW * page. The token fetch reads the first byte of the guard page -> * SIGSEGV inside LZ4_decompress_safe. This violates the documented * contract at sys/vfs/hammer2/hammer2_lz4.h:62-65: * "This function is protected against any kind of buffer overflow * attemps (never writes outside of output buffer, and never reads * outside of input buffer)." * * In-kernel reachability (hammer2_strategy.c:198-205): an on-media LZ4 * block with compressed_size==0 passes the KKASSERT at :199 * ((uint32_t)0 <= bytes - 4) on INVARIANTS kernels and reaches * LZ4_decompress_safe(&data[4], ..., 0, b_bufsize). See trigger script. * * TEST A2 (control): inputSize==1, source={0x00} — the canonical "null" * LZ4 stream per upstream r96's comment ("A correctly formed * null-compressed LZ4 must have at least one byte (token=0)") decodes * cleanly to 0 bytes. Only the inputSize==0 case is broken. * * TEST B (negative proof / margin discipline): * 1,000,000+ randomized AND adversarially-structured LZ4 streams with * HONEST inputSize/outputSize, wrapped in PROT_NONE guard pages: * - source ends flush at a page boundary with a guard page after: * ANY read at iend[0] or beyond faults. * - dest page starts after a guard page (catches ref<dest class) and * carries a canary region [oend, page_end) checked after each run: * ANY write at oend[0] or beyond is detected (analysis bound: all * writes stay <= oend-1; wildcopy packets stop at oend-5..oend-1). * Result: zero faults => given honest sizes the r97 decoder is * memory-safe on LP64 (what DF-0805's caller fails to provide). * * Compile: cc -O2 -Wall -o lz4_zero_input_harness lz4_zero_input_harness.c * Run: ./lz4_zero_input_harness [fuzz_iterations] */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <signal.h> #include <setjmp.h> #include <sys/mman.h> #include <stdint.h> /* ===================================================================== * Verbatim excerpt of sys/vfs/hammer2/hammer2_lz4.c — decompression only. * ===================================================================== */ #define MEMORY_USAGE 14 #define LZ4_ARCH64 1 /* x86_64: pc64 + vkernel64 only */ #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L typedef uint8_t BYTE; typedef uint16_t U16; typedef uint32_t U32; typedef int32_t S32; typedef uint64_t U64; #else typedef unsigned char BYTE; typedef unsigned short U16; typedef unsigned int U32; typedef signed int S32; typedef unsigned long long U64; #endif #define _PACKED __attribute__ ((packed)) typedef struct _U16_S { U16 v; } _PACKED U16_S; typedef struct _U32_S { U32 v; } _PACKED U32_S; typedef struct _U64_S { U64 v; } _PACKED U64_S; #define A64(x) (((U64_S *)(x))->v) #define A32(x) (((U32_S *)(x))->v) #define A16(x) (((U16_S *)(x))->v) #define MINMATCH 4 #define COPYLENGTH 8 #define LASTLITERALS 5 #define MFLIMIT (COPYLENGTH+MINMATCH) #define ML_BITS 4 #define ML_MASK ((1U<<ML_BITS)-1) #define RUN_BITS (8-ML_BITS) #define RUN_MASK ((1U<<RUN_BITS)-1) #if LZ4_ARCH64 # define STEPSIZE 8 # define LZ4_COPYSTEP(s,d) A64(d) = A64(s); d+=8; s+=8; # define LZ4_COPYPACKET(s,d) LZ4_COPYSTEP(s,d) # define LZ4_SECURECOPY(s,d,e) if (d<e) LZ4_WILDCOPY(s,d,e) #else # define STEPSIZE 4 # define LZ4_COPYSTEP(s,d) A32(d) = A32(s); d+=4; s+=4; # define LZ4_COPYPACKET(s,d) LZ4_COPYSTEP(s,d); LZ4_COPYSTEP(s,d); # define LZ4_SECURECOPY LZ4_WILDCOPY #endif #define LZ4_WILDCOPY(s,d,e) do { LZ4_COPYPACKET(s,d) } while (d<e); #define LZ4_BLINDCOPY(s,d,l) { BYTE* e=(d)+(l); LZ4_WILDCOPY(s,d,e); d=e; } #define LZ4_READ_LITTLEENDIAN_16(d,s,p) { d = (s) - A16(p); } #define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) #if (GCC_VERSION >= 302) || defined(__clang__) # define expect(expr,value) (__builtin_expect ((expr),(value)) ) #else # define expect(expr,value) (expr) #endif #define likely(expr) expect((expr) != 0, 1) #define unlikely(expr) expect((expr) != 0, 0) typedef enum { noPrefix = 0, withPrefix = 1 } prefix64k_directive; typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } end_directive; typedef enum { full = 0, partial = 1 } exit_directive; /* Verbatim from sys/vfs/hammer2/hammer2_lz4.c:372-517 */ static inline int LZ4_decompress_generic( char* source, char* dest, int inputSize, int outputSize, int endOnInput, int prefix64k, int partialDecoding, int targetOutputSize) { BYTE* restrict ip = (BYTE*) source; BYTE* ref; BYTE* iend = ip + inputSize; BYTE* op = (BYTE*) dest; BYTE* oend = op + outputSize; BYTE* cpy; BYTE* oexit = op + targetOutputSize; size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; #if LZ4_ARCH64 size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3}; #endif if ((partialDecoding) && (oexit> oend-MFLIMIT)) oexit = oend-MFLIMIT; if unlikely(outputSize==0) goto _output_error; if ((endOnInput) && unlikely(inputSize==0)) goto _output_error; /* FIX DF-2664: r96/v1.9.4 guard */ while (1) { unsigned token; size_t length; token = *ip++; /* <-- hammer2_lz4.c:418 */ if ((length=(token>>ML_BITS)) == RUN_MASK) { unsigned s=255; while (((endOnInput)?ip<iend:1) && (s==255)) { s = *ip++; length += s; } } cpy = op+length; if (((endOnInput) && ((cpy>(partialDecoding?oexit:oend-MFLIMIT)) || (ip+length>iend-(2+1+LASTLITERALS))) ) || ((!endOnInput) && (cpy>oend-COPYLENGTH))) { if (partialDecoding) { if (cpy > oend) goto _output_error; if ((endOnInput) && (ip+length > iend)) goto _output_error; } else { if ((!endOnInput) && (cpy != oend)) goto _output_error; if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; } memcpy(op, ip, length); ip += length; op += length; break; } LZ4_WILDCOPY(ip, op, cpy); ip -= (op-cpy); op = cpy; LZ4_READ_LITTLEENDIAN_16(ref,cpy,ip); ip+=2; if ((prefix64k==noPrefix) && unlikely(ref < (BYTE*)dest)) goto _output_error; if ((length=(token&ML_MASK)) == ML_MASK) { while (endOnInput ? ip<iend-(LASTLITERALS+1) : 1) { unsigned s = *ip++; length += s; if (s==255) continue; break; } } if unlikely((op-ref)<STEPSIZE) { #if LZ4_ARCH64 size_t dec64 = dec64table[op-ref]; #else const size_t dec64 = 0; #endif op[0] = ref[0]; op[1] = ref[1]; op[2] = ref[2]; op[3] = ref[3]; op += 4, ref += 4; ref -= dec32table[op-ref]; A32(op) = A32(ref); op += STEPSIZE-4; ref -= dec64; } else { LZ4_COPYSTEP(ref,op); } cpy = op + length - (STEPSIZE-4); if unlikely(cpy>oend-(COPYLENGTH)-(STEPSIZE-4)) { if (cpy > oend-LASTLITERALS) goto _output_error; LZ4_SECURECOPY(ref, op, (oend-COPYLENGTH)); while(op<cpy) *op++=*ref++; op=cpy; continue; } LZ4_WILDCOPY(ref, op, cpy); op=cpy; } if (endOnInput) return (int) (((char*)op)-dest); else return (int) (((char*)ip)-source); _output_error: return (int) (-(((char*)ip)-source))-1; } /* Verbatim from sys/vfs/hammer2/hammer2_lz4.c:520-525 */ int LZ4_decompress_safe(char* source, char* dest, int inputSize, int maxOutputSize) { return LZ4_decompress_generic(source, dest, inputSize, maxOutputSize, endOnInputSize, noPrefix, full, 0); } /* ===================================================================== * Harness * ===================================================================== */ static sigjmp_buf jb; static volatile sig_atomic_t in_decoder; static void *fault_addr; static void segv_handler(int sig, siginfo_t *si, void *uc) { (void)sig; (void)uc; fault_addr = si->si_addr; in_decoder = 0; siglongjmp(jb, 1); } static size_t pagesz; int main(int argc, char **argv) { unsigned long fuzz_iters = 1000000; if (argc > 1) fuzz_iters = strtoul(argv[1], NULL, 0); pagesz = (size_t)sysconf(_SC_PAGESIZE); struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = segv_handler; sa.sa_flags = SA_SIGINFO; sigemptyset(&sa.sa_mask); sigaction(SIGSEGV, &sa, NULL); sigaction(SIGBUS, &sa, NULL); puts("[harness] DF-2664: LZ4_decompress_safe() token read with inputSize==0"); puts("[harness] decoder = verbatim sys/vfs/hammer2/hammer2_lz4.c (upstream LZ4 r97)"); /* * TEST A — the finding. * Map [ RW | GUARD ]; place a 64 KiB output buffer normally, and the * SOURCE at the very end of the RW page. inputSize = 0. */ { char *region = mmap(NULL, 2 * pagesz, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0); if (region == MAP_FAILED) { perror("mmap"); return 1; } if (mprotect(region + pagesz, pagesz, PROT_NONE) != 0) { perror("mprotect"); return 1; } char *src = region + pagesz; /* == end of RW page == iend */ char *dst = calloc(1, 65536); int r = -12345; puts("[A] calling LZ4_decompress_safe(src=end_of_page, dst, inputSize=0, 65536)"); in_decoder = 1; if (sigsetjmp(jb, 1) == 0) { r = LZ4_decompress_safe(src, dst, 0, 65536); in_decoder = 0; /* FIXED build: the r96/v1.9.4 guard must reject inputSize==0 * cleanly BEFORE the token fetch. */ printf("[A] returned %d WITHOUT faulting\n", r); if (r < 0) { printf("FIX VALIDATED - inputSize==0 cleanly rejected, no OOB read\n"); free(dst); munmap(region, 2*pagesz); goto test_a2; } else { printf("FIX FAILED - inputSize==0 accepted\n"); free(dst); munmap(region, 2*pagesz); return 1; } } printf("[A] SIGSEGV at %p while inside LZ4_decompress_safe()\n", fault_addr); printf("[A] faulting address == src (== iend): %p ; delta = %ld\n", (void *)src, (long)((char *)fault_addr - src)); puts("[A] -> LZ4_decompress_safe() dereferenced source[0] with inputSize==0:"); puts("[A] 1-byte OOB read past the declared input buffer."); puts("OOB READ CONFIRMED — DF-2664 (hammer2_lz4.c:418)"); free(dst); munmap(region, 2*pagesz); } /* * TEST A2 — control: the canonical 1-byte null stream works. */ test_a2: { char src[1] = { 0x00 }; char dst[256]; memset(dst, 0xA5, sizeof(dst)); int r = LZ4_decompress_safe(src, dst, 1, sizeof(dst)); printf("[A2] inputSize=1, token=0x00 -> return %d (expect 0)\n", r); if (r != 0) { puts("[A2] UNEXPECTED: canonical null stream failed"); return 1; } puts("[A2] control OK: with inputSize>=1 the same entry is well-behaved;"); puts("[A2] only inputSize==0 is broken (guard dropped in upstream r97)."); } /* * TEST B — margin-discipline fuzz (negative proof). * * src: [ GUARD | RW page(s) ] with the stream placed flush against * the final guard page: any read at iend[0..] faults. * dst: [ GUARD | RW page ] with canary in [oend, page_end): * any write at oend[0..] corrupts the canary; reads/writes * before dest fault on the leading guard page. */ { unsigned char *srcpages = mmap(NULL, 2 * pagesz, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0); unsigned char *dstpages = mmap(NULL, 2 * pagesz, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0); mprotect(srcpages, pagesz, PROT_NONE); /* guard BEFORE src region */ mprotect(dstpages, pagesz, PROT_NONE); /* guard BEFORE dst */ unsigned char *srcarea = srcpages + pagesz; /* one RW page */ unsigned char *dst = dstpages + pagesz; srandom(0xDF2664u); unsigned long i; unsigned long accepted = 0, rejected = 0; const size_t canary_off_min = 32; /* min canary size */ size_t max_in = pagesz - 8; /* stream must fit one page */ for (i = 0; i < fuzz_iters; i++) { size_t in; int outSize; /* --- generate input --- */ unsigned int mode = random() % 10; if (i < 16) { in = 1 + (i % 20); /* tiny streams first */ } else { in = 1 + (size_t)(random() % max_in); } outSize = 1 + (int)(random() % (pagesz - canary_off_min - 1)); if (i % 7 == 0) outSize = 1 + (int)(random() % 16); /* exercise tiny outputs */ unsigned char *p = srcarea + (pagesz - in); /* flush to end */ size_t n; if (mode == 0) { /* all 0xFF */ memset(p, 0xFF, in); } else if (mode == 1) { /* all zero */ memset(p, 0x00, in); } else if (mode <= 5) { /* structured */ n = 0; while (n < in) { unsigned litn, matn; unsigned tok; litn = random() % 20; matn = random() % 20; if (random() % 3 == 0) litn = RUN_MASK; if (random() % 3 == 0) matn = ML_MASK; tok = (litn << ML_BITS) | matn; if (n < in) p[n++] = tok; if (litn == RUN_MASK) { int k = random() % 4; while (k-- > 0 && n < in) p[n++] = (random()%5==0) ? random()%255 : 0xFF; if (n < in) p[n++] = random() % 255; } size_t litbytes = random() % 24; while (litbytes-- > 0 && n < in) p[n++] = random() % 255; /* offset */ if (n + 1 < in) { unsigned short off; switch (random() % 6) { case 0: off = 0; break; case 1: off = 1; break; case 2: off = 2; break; case 3: off = 7; break; case 4: off = 0xFFFF; break; default: off = (unsigned short)(random() % 512); } memcpy(p + n, &off, 2); n += 2; } if (matn == ML_MASK) { int k = random() % 4; while (k-- > 0 && n < in) p[n++] = 0xFF; if (n < in) p[n++] = random() % 255; } } } else { /* pure random */ for (n = 0; n < in; n++) p[n] = (unsigned char)(random() & 0xFF); } /* --- canary + run --- */ size_t canlen = pagesz - (size_t)outSize; memset(dst + outSize, 0xC3, canlen); /* canary after oend */ memset(dst, 0x5A, (size_t)outSize); /* poison output */ in_decoder = 1; if (sigsetjmp(jb, 1) != 0) { printf("[B] FAULT at iter %lu mode %u in=%zu out=%d addr=%p\n", i, mode, in, outSize, fault_addr); char path[128]; snprintf(path, sizeof(path), "/tmp/df2664_fault_input.bin"); FILE *f = fopen(path, "wb"); if (f) { fwrite(p, in, 1, f); fclose(f); } printf("[B] input dumped to %s\n", path); puts("FUZZ FAULT — decoder violated the guard/canary discipline!"); return 1; } int r = LZ4_decompress_safe((char *)p, (char *)dst, (int)in, outSize); in_decoder = 0; /* --- verify --- */ size_t j; for (j = 0; j < canlen; j++) { if (dst[outSize + j] != 0xC3) { printf("[B] CANARY CORRUPT at iter %lu: dst[%d]=%02x\n", i, outSize + (int)j, dst[outSize + j]); puts("WRITE PAST OEND — decoder wrote beyond outputSize!"); return 1; } } if (r > outSize || r < -(int)(in + 2)) { printf("[B] INSANE RETURN at iter %lu: r=%d in=%zu out=%d\n", i, r, in, outSize); return 1; } if (r < 0) rejected++; else accepted++; } printf("[B] %lu iterations: %lu decoded ok, %lu rejected, " "0 faults, 0 canary corruptions\n", fuzz_iters, accepted, rejected); puts("[B] NEGATIVE PROOF (breadth): with honest (inputSize,outputSize)"); puts("[B] the r97 decoder never reads past iend and never writes past oend."); /* * TEST C — depth fuzz: generate *valid-shaped* streams (small * literal runs + in-window offsets + short matches, ending with * an exact final literal run) so the decoder walks MANY loop * iterations deep into match-copy/overlap machinery, then mutate * a few bytes (or truncate) to land near-valid inputs exactly on * the margin arithmetic (oend-5/-8/-12, iend-6/-8 boundaries). */ { unsigned long accepted2 = 0, rejected2 = 0, mutated = 0; unsigned char *gen = calloc(1, pagesz); for (i = 0; i < fuzz_iters; i++) { size_t g = 0; size_t outpos = 0; /* simulated output position */ size_t maxg = 64 + (size_t)(random() % (max_in - 64)); int outSize2 = 64 + (int)(random() % (pagesz - canary_off_min - 64)); while (g + 16 < maxg) { unsigned lit = random() % 30; unsigned mat = random() % 18; unsigned tok = ((lit < RUN_MASK ? lit : RUN_MASK) << ML_BITS) | (mat < ML_MASK ? mat : ML_MASK); gen[g++] = tok; if (lit >= RUN_MASK) { /* ext bytes */ unsigned e = random() % 3; while (e-- > 0 && g + 4 < maxg) gen[g++] = 0xFF; if (g + 4 < maxg) gen[g++] = random() % 200; lit += 255 * (random() % 2); } while (lit-- > 0 && g + 4 < maxg) gen[g++] = random() & 0xFF; outpos += (tok >> ML_BITS); /* offset within simulated output window (0 allowed) */ size_t offmax = outpos ? outpos : (tok >> ML_BITS); unsigned short off = (unsigned short)(random() % (offmax ? (offmax > 4096 ? 4096 : offmax) : 1)); if (random() % 11 == 0) off = 0; if (random() % 9 == 0) off = 1 + random() % 8; /* overlap d=1..8 */ if (g + 2 < maxg) { gen[g++] = off & 0xFF; gen[g++] = off >> 8; } if ((tok & ML_MASK) == ML_MASK) { unsigned e = random() % 3; while (e-- > 0 && g + 4 < maxg) gen[g++] = 0xFF; if (g + 4 < maxg) gen[g++] = random() % 200; } outpos += (tok & ML_MASK); } /* final literal run consuming the rest exactly */ { size_t rem = maxg - g; if (rem > 5 && rem < pagesz) { unsigned tokrun = (rem < RUN_MASK ? rem : RUN_MASK); gen[g++] = tokrun << ML_BITS; size_t r2 = rem; if (rem >= RUN_MASK) { r2 -= RUN_MASK; while (r2 >= 255 && g + 300 < pagesz) { gen[g++] = 0xFF; r2 -= 255; } gen[g++] = r2; r2 = 0; } while (r2-- > 0 && g < pagesz) gen[g++] = random() & 0xFF; } } if (g > max_in) g = max_in; /* mutation */ if (random() % 2) { mutated++; int nm = 1 + random() % 3; while (nm-- > 0 && g > 1) gen[random() % g] = random() & 0xFF; if (random() % 4 == 0 && g > 2) g = 1 + random() % g; /* truncate */ } size_t in2 = g; unsigned char *p2 = srcarea + (pagesz - in2); memmove(p2, gen, in2); size_t canlen2 = pagesz - (size_t)outSize2; memset(dst + outSize2, 0xC3, canlen2); memset(dst, 0x5A, (size_t)outSize2); in_decoder = 1; if (sigsetjmp(jb, 1) != 0) { printf("[C] FAULT at iter %lu in=%zu out=%d addr=%p\n", i, in2, outSize2, fault_addr); FILE *f = fopen("/tmp/df2664_fault_input.bin", "wb"); if (f) { fwrite(p2, in2, 1, f); fclose(f); } puts("FUZZ FAULT — decoder violated the guard/canary discipline!"); return 1; } int r = LZ4_decompress_safe((char *)p2, (char *)dst, (int)in2, outSize2); in_decoder = 0; for (size_t j2 = 0; j2 < canlen2; j2++) { if (dst[outSize2 + j2] != 0xC3) { printf("[C] CANARY CORRUPT at iter %lu dst[%d]=%02x\n", i, outSize2 + (int)j2, dst[outSize2 + j2]); puts("WRITE PAST OEND!"); return 1; } } if (r > outSize2 || r < -(int)(in2 + 2)) { printf("[C] INSANE RETURN iter %lu r=%d in=%zu out=%d\n", i, r, in2, outSize2); return 1; } if (r < 0) rejected2++; else accepted2++; } printf("[C] %lu valid-shaped/mutated iterations (%lu mutated): " "%lu decoded ok, %lu rejected, 0 faults, 0 canary corruptions\n", fuzz_iters, mutated, accepted2, rejected2); puts("[C] NEGATIVE PROOF (depth): deep-parsing streams also stay in bounds."); free(gen); } } puts("DONE"); return 0; } |