string.c revision f8e2c06cea1548c437761cb65cfbf97d50a057a7
1// RUN: %clang_cc1 -analyze -analyzer-checker=core,unix.cstring,alpha.unix.cstring,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify %s 2// RUN: %clang_cc1 -analyze -DUSE_BUILTINS -analyzer-checker=core,unix.cstring,alpha.unix.cstring,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify %s 3// RUN: %clang_cc1 -analyze -DVARIANT -analyzer-checker=core,unix.cstring,alpha.unix.cstring,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify %s 4// RUN: %clang_cc1 -analyze -DUSE_BUILTINS -DVARIANT -analyzer-checker=alpha.security.taint,core,unix.cstring,alpha.unix.cstring,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify %s 5 6//===----------------------------------------------------------------------=== 7// Declarations 8//===----------------------------------------------------------------------=== 9 10// Some functions are so similar to each other that they follow the same code 11// path, such as memcpy and __memcpy_chk, or memcmp and bcmp. If VARIANT is 12// defined, make sure to use the variants instead to make sure they are still 13// checked by the analyzer. 14 15// Some functions are implemented as builtins. These should be #defined as 16// BUILTIN(f), which will prepend "__builtin_" if USE_BUILTINS is defined. 17 18// Functions that have variants and are also available as builtins should be 19// declared carefully! See memcpy() for an example. 20 21#ifdef USE_BUILTINS 22# define BUILTIN(f) __builtin_ ## f 23#else /* USE_BUILTINS */ 24# define BUILTIN(f) f 25#endif /* USE_BUILTINS */ 26 27#define NULL 0 28typedef typeof(sizeof(int)) size_t; 29 30void clang_analyzer_eval(int); 31 32int scanf(const char *restrict format, ...); 33 34//===----------------------------------------------------------------------=== 35// strlen() 36//===----------------------------------------------------------------------=== 37 38#define strlen BUILTIN(strlen) 39size_t strlen(const char *s); 40 41void strlen_constant0() { 42 clang_analyzer_eval(strlen("123") == 3); // expected-warning{{TRUE}} 43} 44 45void strlen_constant1() { 46 const char *a = "123"; 47 clang_analyzer_eval(strlen(a) == 3); // expected-warning{{TRUE}} 48} 49 50void strlen_constant2(char x) { 51 char a[] = "123"; 52 clang_analyzer_eval(strlen(a) == 3); // expected-warning{{TRUE}} 53 54 a[0] = x; 55 clang_analyzer_eval(strlen(a) == 3); // expected-warning{{UNKNOWN}} 56} 57 58size_t strlen_null() { 59 return strlen(0); // expected-warning{{Null pointer argument in call to string length function}} 60} 61 62size_t strlen_fn() { 63 return strlen((char*)&strlen_fn); // expected-warning{{Argument to string length function is the address of the function 'strlen_fn', which is not a null-terminated string}} 64} 65 66size_t strlen_nonloc() { 67label: 68 return strlen((char*)&&label); // expected-warning{{Argument to string length function is the address of the label 'label', which is not a null-terminated string}} 69} 70 71void strlen_subregion() { 72 struct two_strings { char a[2], b[2]; }; 73 extern void use_two_strings(struct two_strings *); 74 75 struct two_strings z; 76 use_two_strings(&z); 77 78 size_t a = strlen(z.a); 79 z.b[0] = 5; 80 size_t b = strlen(z.a); 81 if (a == 0) 82 clang_analyzer_eval(b == 0); // expected-warning{{TRUE}} 83 84 use_two_strings(&z); 85 86 size_t c = strlen(z.a); 87 if (a == 0) 88 clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}} 89} 90 91extern void use_string(char *); 92void strlen_argument(char *x) { 93 size_t a = strlen(x); 94 size_t b = strlen(x); 95 if (a == 0) 96 clang_analyzer_eval(b == 0); // expected-warning{{TRUE}} 97 98 use_string(x); 99 100 size_t c = strlen(x); 101 if (a == 0) 102 clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}} 103} 104 105extern char global_str[]; 106void strlen_global() { 107 size_t a = strlen(global_str); 108 size_t b = strlen(global_str); 109 if (a == 0) { 110 clang_analyzer_eval(b == 0); // expected-warning{{TRUE}} 111 // Make sure clang_analyzer_eval does not invalidate globals. 112 clang_analyzer_eval(strlen(global_str) == 0); // expected-warning{{TRUE}} 113 } 114 115 // Call a function with unknown effects, which should invalidate globals. 116 use_string(0); 117 118 size_t c = strlen(global_str); 119 if (a == 0) 120 clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}} 121} 122 123void strlen_indirect(char *x) { 124 size_t a = strlen(x); 125 char *p = x; 126 char **p2 = &p; 127 size_t b = strlen(x); 128 if (a == 0) 129 clang_analyzer_eval(b == 0); // expected-warning{{TRUE}} 130 131 extern void use_string_ptr(char*const*); 132 use_string_ptr(p2); 133 134 size_t c = strlen(x); 135 if (a == 0) 136 clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}} 137} 138 139void strlen_indirect2(char *x) { 140 size_t a = strlen(x); 141 char *p = x; 142 char **p2 = &p; 143 extern void use_string_ptr2(char**); 144 use_string_ptr2(p2); 145 146 size_t c = strlen(x); 147 if (a == 0) 148 clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}} 149} 150 151void strlen_liveness(const char *x) { 152 if (strlen(x) < 5) 153 return; 154 clang_analyzer_eval(strlen(x) < 5); // expected-warning{{FALSE}} 155} 156 157//===----------------------------------------------------------------------=== 158// strnlen() 159//===----------------------------------------------------------------------=== 160 161size_t strnlen(const char *s, size_t maxlen); 162 163void strnlen_constant0() { 164 clang_analyzer_eval(strnlen("123", 10) == 3); // expected-warning{{TRUE}} 165} 166 167void strnlen_constant1() { 168 const char *a = "123"; 169 clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{TRUE}} 170} 171 172void strnlen_constant2(char x) { 173 char a[] = "123"; 174 clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{TRUE}} 175 a[0] = x; 176 clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{UNKNOWN}} 177} 178 179void strnlen_constant4() { 180 clang_analyzer_eval(strnlen("123456", 3) == 3); // expected-warning{{TRUE}} 181} 182 183void strnlen_constant5() { 184 const char *a = "123456"; 185 clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{TRUE}} 186} 187 188void strnlen_constant6(char x) { 189 char a[] = "123456"; 190 clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{TRUE}} 191 a[0] = x; 192 clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{UNKNOWN}} 193} 194 195size_t strnlen_null() { 196 return strnlen(0, 3); // expected-warning{{Null pointer argument in call to string length function}} 197} 198 199size_t strnlen_fn() { 200 return strnlen((char*)&strlen_fn, 3); // expected-warning{{Argument to string length function is the address of the function 'strlen_fn', which is not a null-terminated string}} 201} 202 203size_t strnlen_nonloc() { 204label: 205 return strnlen((char*)&&label, 3); // expected-warning{{Argument to string length function is the address of the label 'label', which is not a null-terminated string}} 206} 207 208void strnlen_zero() { 209 clang_analyzer_eval(strnlen("abc", 0) == 0); // expected-warning{{TRUE}} 210 clang_analyzer_eval(strnlen(NULL, 0) == 0); // expected-warning{{TRUE}} 211} 212 213size_t strnlen_compound_literal() { 214 // This used to crash because we don't model the string lengths of 215 // compound literals. 216 return strnlen((char[]) { 'a', 'b', 0 }, 1); 217} 218 219size_t strnlen_unknown_limit(float f) { 220 // This used to crash because we don't model the integer values of floats. 221 return strnlen("abc", (int)f); 222} 223 224void strnlen_is_not_strlen(char *x) { 225 clang_analyzer_eval(strnlen(x, 10) == strlen(x)); // expected-warning{{UNKNOWN}} 226} 227 228void strnlen_at_limit(char *x) { 229 size_t len = strnlen(x, 10); 230 clang_analyzer_eval(len <= 10); // expected-warning{{TRUE}} 231 clang_analyzer_eval(len == 10); // expected-warning{{UNKNOWN}} 232 clang_analyzer_eval(len < 10); // expected-warning{{UNKNOWN}} 233} 234 235void strnlen_at_actual(size_t limit) { 236 size_t len = strnlen("abc", limit); 237 clang_analyzer_eval(len <= 3); // expected-warning{{TRUE}} 238 // This is due to eager assertion in strnlen. 239 if (limit == 0) { 240 clang_analyzer_eval(len == 0); // expected-warning{{TRUE}} 241 } else { 242 clang_analyzer_eval(len == 3); // expected-warning{{UNKNOWN}} 243 clang_analyzer_eval(len < 3); // expected-warning{{UNKNOWN}} 244 } 245} 246 247//===----------------------------------------------------------------------=== 248// strcpy() 249//===----------------------------------------------------------------------=== 250 251#ifdef VARIANT 252 253#define __strcpy_chk BUILTIN(__strcpy_chk) 254char *__strcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen); 255 256#define strcpy(a,b) __strcpy_chk(a,b,(size_t)-1) 257 258#else /* VARIANT */ 259 260#define strcpy BUILTIN(strcpy) 261char *strcpy(char *restrict s1, const char *restrict s2); 262 263#endif /* VARIANT */ 264 265 266void strcpy_null_dst(char *x) { 267 strcpy(NULL, x); // expected-warning{{Null pointer argument in call to string copy function}} 268} 269 270void strcpy_null_src(char *x) { 271 strcpy(x, NULL); // expected-warning{{Null pointer argument in call to string copy function}} 272} 273 274void strcpy_fn(char *x) { 275 strcpy(x, (char*)&strcpy_fn); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}} 276} 277 278void strcpy_fn_const(char *x) { 279 strcpy(x, (const char*)&strcpy_fn); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}} 280} 281 282extern int globalInt; 283void strcpy_effects(char *x, char *y) { 284 char a = x[0]; 285 if (globalInt != 42) 286 return; 287 288 clang_analyzer_eval(strcpy(x, y) == x); // expected-warning{{TRUE}} 289 clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}} 290 clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}} 291 clang_analyzer_eval(globalInt == 42); // expected-warning{{TRUE}} 292} 293 294void strcpy_overflow(char *y) { 295 char x[4]; 296 if (strlen(y) == 4) 297 strcpy(x, y); // expected-warning{{String copy function overflows destination buffer}} 298} 299 300void strcpy_no_overflow(char *y) { 301 char x[4]; 302 if (strlen(y) == 3) 303 strcpy(x, y); // no-warning 304} 305 306//===----------------------------------------------------------------------=== 307// stpcpy() 308//===----------------------------------------------------------------------=== 309 310#ifdef VARIANT 311 312#define __stpcpy_chk BUILTIN(__stpcpy_chk) 313char *__stpcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen); 314 315#define stpcpy(a,b) __stpcpy_chk(a,b,(size_t)-1) 316 317#else /* VARIANT */ 318 319#define stpcpy BUILTIN(stpcpy) 320char *stpcpy(char *restrict s1, const char *restrict s2); 321 322#endif /* VARIANT */ 323 324 325void stpcpy_effect(char *x, char *y) { 326 char a = x[0]; 327 328 clang_analyzer_eval(stpcpy(x, y) == &x[strlen(y)]); // expected-warning{{TRUE}} 329 clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}} 330 clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}} 331} 332 333void stpcpy_overflow(char *y) { 334 char x[4]; 335 if (strlen(y) == 4) 336 stpcpy(x, y); // expected-warning{{String copy function overflows destination buffer}} 337} 338 339void stpcpy_no_overflow(char *y) { 340 char x[4]; 341 if (strlen(y) == 3) 342 stpcpy(x, y); // no-warning 343} 344 345//===----------------------------------------------------------------------=== 346// strcat() 347//===----------------------------------------------------------------------=== 348 349#ifdef VARIANT 350 351#define __strcat_chk BUILTIN(__strcat_chk) 352char *__strcat_chk(char *restrict s1, const char *restrict s2, size_t destlen); 353 354#define strcat(a,b) __strcat_chk(a,b,(size_t)-1) 355 356#else /* VARIANT */ 357 358#define strcat BUILTIN(strcat) 359char *strcat(char *restrict s1, const char *restrict s2); 360 361#endif /* VARIANT */ 362 363 364void strcat_null_dst(char *x) { 365 strcat(NULL, x); // expected-warning{{Null pointer argument in call to string copy function}} 366} 367 368void strcat_null_src(char *x) { 369 strcat(x, NULL); // expected-warning{{Null pointer argument in call to string copy function}} 370} 371 372void strcat_fn(char *x) { 373 strcat(x, (char*)&strcat_fn); // expected-warning{{Argument to string copy function is the address of the function 'strcat_fn', which is not a null-terminated string}} 374} 375 376void strcat_effects(char *y) { 377 char x[8] = "123"; 378 size_t orig_len = strlen(x); 379 char a = x[0]; 380 381 if (strlen(y) != 4) 382 return; 383 384 clang_analyzer_eval(strcat(x, y) == x); // expected-warning{{TRUE}} 385 clang_analyzer_eval((int)strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}} 386} 387 388void strcat_overflow_0(char *y) { 389 char x[4] = "12"; 390 if (strlen(y) == 4) 391 strcat(x, y); // expected-warning{{String copy function overflows destination buffer}} 392} 393 394void strcat_overflow_1(char *y) { 395 char x[4] = "12"; 396 if (strlen(y) == 3) 397 strcat(x, y); // expected-warning{{String copy function overflows destination buffer}} 398} 399 400void strcat_overflow_2(char *y) { 401 char x[4] = "12"; 402 if (strlen(y) == 2) 403 strcat(x, y); // expected-warning{{String copy function overflows destination buffer}} 404} 405 406void strcat_no_overflow(char *y) { 407 char x[5] = "12"; 408 if (strlen(y) == 2) 409 strcat(x, y); // no-warning 410} 411 412void strcat_symbolic_dst_length(char *dst) { 413 strcat(dst, "1234"); 414 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 415} 416 417void strcat_symbolic_dst_length_taint(char *dst) { 418 scanf("%s", dst); // Taint data. 419 strcat(dst, "1234"); 420 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 421} 422 423void strcat_unknown_src_length(char *src, int offset) { 424 char dst[8] = "1234"; 425 strcat(dst, &src[offset]); 426 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 427} 428 429// There is no strcat_unknown_dst_length because if we can't get a symbolic 430// length for the "before" strlen, we won't be able to set one for "after". 431 432void strcat_too_big(char *dst, char *src) { 433 if (strlen(dst) != (((size_t)0) - 2)) 434 return; 435 if (strlen(src) != 2) 436 return; 437 strcat(dst, src); // expected-warning{{This expression will create a string whose length is too big to be represented as a size_t}} 438} 439 440 441//===----------------------------------------------------------------------=== 442// strncpy() 443//===----------------------------------------------------------------------=== 444 445#ifdef VARIANT 446 447#define __strncpy_chk BUILTIN(__strncpy_chk) 448char *__strncpy_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen); 449 450#define strncpy(a,b,n) __strncpy_chk(a,b,n,(size_t)-1) 451 452#else /* VARIANT */ 453 454#define strncpy BUILTIN(strncpy) 455char *strncpy(char *restrict s1, const char *restrict s2, size_t n); 456 457#endif /* VARIANT */ 458 459 460void strncpy_null_dst(char *x) { 461 strncpy(NULL, x, 5); // expected-warning{{Null pointer argument in call to string copy function}} 462} 463 464void strncpy_null_src(char *x) { 465 strncpy(x, NULL, 5); // expected-warning{{Null pointer argument in call to string copy function}} 466} 467 468void strncpy_fn(char *x) { 469 strncpy(x, (char*)&strcpy_fn, 5); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}} 470} 471 472void strncpy_effects(char *x, char *y) { 473 char a = x[0]; 474 475 clang_analyzer_eval(strncpy(x, y, 5) == x); // expected-warning{{TRUE}} 476 clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{UNKNOWN}} 477 clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}} 478} 479 480void strncpy_overflow(char *y) { 481 char x[4]; 482 if (strlen(y) == 4) 483 strncpy(x, y, 5); // expected-warning{{Size argument is greater than the length of the destination buffer}} 484} 485 486void strncpy_no_overflow(char *y) { 487 char x[4]; 488 if (strlen(y) == 3) 489 strncpy(x, y, 5); // expected-warning{{Size argument is greater than the length of the destination buffer}} 490} 491 492void strncpy_no_overflow2(char *y, int n) { 493 if (n <= 4) 494 return; 495 496 char x[4]; 497 if (strlen(y) == 3) 498 strncpy(x, y, n); // expected-warning{{Size argument is greater than the length of the destination buffer}} 499} 500 501void strncpy_truncate(char *y) { 502 char x[4]; 503 if (strlen(y) == 4) 504 strncpy(x, y, 3); // no-warning 505} 506 507void strncpy_no_truncate(char *y) { 508 char x[4]; 509 if (strlen(y) == 3) 510 strncpy(x, y, 3); // no-warning 511} 512 513void strncpy_exactly_matching_buffer(char *y) { 514 char x[4]; 515 strncpy(x, y, 4); // no-warning 516 517 // strncpy does not null-terminate, so we have no idea what the strlen is 518 // after this. 519 clang_analyzer_eval(strlen(x) > 4); // expected-warning{{UNKNOWN}} 520} 521 522void strncpy_zero(char *src) { 523 char dst[] = "123"; 524 strncpy(dst, src, 0); // no-warning 525} 526 527void strncpy_empty() { 528 char dst[] = "123"; 529 char src[] = ""; 530 strncpy(dst, src, 4); // no-warning 531} 532 533//===----------------------------------------------------------------------=== 534// strncat() 535//===----------------------------------------------------------------------=== 536 537#ifdef VARIANT 538 539#define __strncat_chk BUILTIN(__strncat_chk) 540char *__strncat_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen); 541 542#define strncat(a,b,c) __strncat_chk(a,b,c, (size_t)-1) 543 544#else /* VARIANT */ 545 546#define strncat BUILTIN(strncat) 547char *strncat(char *restrict s1, const char *restrict s2, size_t n); 548 549#endif /* VARIANT */ 550 551 552void strncat_null_dst(char *x) { 553 strncat(NULL, x, 4); // expected-warning{{Null pointer argument in call to string copy function}} 554} 555 556void strncat_null_src(char *x) { 557 strncat(x, NULL, 4); // expected-warning{{Null pointer argument in call to string copy function}} 558} 559 560void strncat_fn(char *x) { 561 strncat(x, (char*)&strncat_fn, 4); // expected-warning{{Argument to string copy function is the address of the function 'strncat_fn', which is not a null-terminated string}} 562} 563 564void strncat_effects(char *y) { 565 char x[8] = "123"; 566 size_t orig_len = strlen(x); 567 char a = x[0]; 568 569 if (strlen(y) != 4) 570 return; 571 572 clang_analyzer_eval(strncat(x, y, strlen(y)) == x); // expected-warning{{TRUE}} 573 clang_analyzer_eval(strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}} 574} 575 576void strncat_overflow_0(char *y) { 577 char x[4] = "12"; 578 if (strlen(y) == 4) 579 strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 580} 581 582void strncat_overflow_1(char *y) { 583 char x[4] = "12"; 584 if (strlen(y) == 3) 585 strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 586} 587 588void strncat_overflow_2(char *y) { 589 char x[4] = "12"; 590 if (strlen(y) == 2) 591 strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 592} 593 594void strncat_overflow_3(char *y) { 595 char x[4] = "12"; 596 if (strlen(y) == 4) 597 strncat(x, y, 2); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 598} 599void strncat_no_overflow_1(char *y) { 600 char x[5] = "12"; 601 if (strlen(y) == 2) 602 strncat(x, y, strlen(y)); // no-warning 603} 604 605void strncat_no_overflow_2(char *y) { 606 char x[4] = "12"; 607 if (strlen(y) == 4) 608 strncat(x, y, 1); // no-warning 609} 610 611void strncat_symbolic_dst_length(char *dst) { 612 strncat(dst, "1234", 5); 613 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 614} 615 616void strncat_symbolic_src_length(char *src) { 617 char dst[8] = "1234"; 618 strncat(dst, src, 3); 619 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 620 621 char dst2[8] = "1234"; 622 strncat(dst2, src, 4); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 623} 624 625void strncat_unknown_src_length(char *src, int offset) { 626 char dst[8] = "1234"; 627 strncat(dst, &src[offset], 3); 628 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 629 630 char dst2[8] = "1234"; 631 strncat(dst2, &src[offset], 4); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 632} 633 634// There is no strncat_unknown_dst_length because if we can't get a symbolic 635// length for the "before" strlen, we won't be able to set one for "after". 636 637void strncat_symbolic_limit(unsigned limit) { 638 char dst[6] = "1234"; 639 char src[] = "567"; 640 strncat(dst, src, limit); // no-warning 641 642 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 643 clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}} 644} 645 646void strncat_unknown_limit(float limit) { 647 char dst[6] = "1234"; 648 char src[] = "567"; 649 strncat(dst, src, (size_t)limit); // no-warning 650 651 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 652 clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}} 653} 654 655void strncat_too_big(char *dst, char *src) { 656 if (strlen(dst) != (((size_t)0) - 2)) 657 return; 658 if (strlen(src) != 2) 659 return; 660 strncat(dst, src, 2); // expected-warning{{This expression will create a string whose length is too big to be represented as a size_t}} 661} 662 663void strncat_zero(char *src) { 664 char dst[] = "123"; 665 strncat(dst, src, 0); // no-warning 666} 667 668void strncat_empty() { 669 char dst[8] = "123"; 670 char src[] = ""; 671 strncat(dst, src, 4); // no-warning 672} 673 674//===----------------------------------------------------------------------=== 675// strcmp() 676//===----------------------------------------------------------------------=== 677 678#define strcmp BUILTIN(strcmp) 679int strcmp(const char * s1, const char * s2); 680 681void strcmp_constant0() { 682 clang_analyzer_eval(strcmp("123", "123") == 0); // expected-warning{{TRUE}} 683} 684 685void strcmp_constant_and_var_0() { 686 char *x = "123"; 687 clang_analyzer_eval(strcmp(x, "123") == 0); // expected-warning{{TRUE}} 688} 689 690void strcmp_constant_and_var_1() { 691 char *x = "123"; 692 clang_analyzer_eval(strcmp("123", x) == 0); // expected-warning{{TRUE}} 693} 694 695void strcmp_0() { 696 char *x = "123"; 697 char *y = "123"; 698 clang_analyzer_eval(strcmp(x, y) == 0); // expected-warning{{TRUE}} 699} 700 701void strcmp_1() { 702 char *x = "234"; 703 char *y = "123"; 704 clang_analyzer_eval(strcmp(x, y) == 1); // expected-warning{{TRUE}} 705} 706 707void strcmp_2() { 708 char *x = "123"; 709 char *y = "234"; 710 clang_analyzer_eval(strcmp(x, y) == -1); // expected-warning{{TRUE}} 711} 712 713void strcmp_null_0() { 714 char *x = NULL; 715 char *y = "123"; 716 strcmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}} 717} 718 719void strcmp_null_1() { 720 char *x = "123"; 721 char *y = NULL; 722 strcmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}} 723} 724 725void strcmp_diff_length_0() { 726 char *x = "12345"; 727 char *y = "234"; 728 clang_analyzer_eval(strcmp(x, y) == -1); // expected-warning{{TRUE}} 729} 730 731void strcmp_diff_length_1() { 732 char *x = "123"; 733 char *y = "23456"; 734 clang_analyzer_eval(strcmp(x, y) == -1); // expected-warning{{TRUE}} 735} 736 737void strcmp_diff_length_2() { 738 char *x = "12345"; 739 char *y = "123"; 740 clang_analyzer_eval(strcmp(x, y) == 1); // expected-warning{{TRUE}} 741} 742 743void strcmp_diff_length_3() { 744 char *x = "123"; 745 char *y = "12345"; 746 clang_analyzer_eval(strcmp(x, y) == -1); // expected-warning{{TRUE}} 747} 748 749void strcmp_embedded_null () { 750 clang_analyzer_eval(strcmp("\0z", "\0y") == 0); // expected-warning{{TRUE}} 751} 752 753void strcmp_unknown_arg (char *unknown) { 754 clang_analyzer_eval(strcmp(unknown, unknown) == 0); // expected-warning{{TRUE}} 755} 756 757//===----------------------------------------------------------------------=== 758// strncmp() 759//===----------------------------------------------------------------------=== 760 761#define strncmp BUILTIN(strncmp) 762int strncmp(const char *s1, const char *s2, size_t n); 763 764void strncmp_constant0() { 765 clang_analyzer_eval(strncmp("123", "123", 3) == 0); // expected-warning{{TRUE}} 766} 767 768void strncmp_constant_and_var_0() { 769 char *x = "123"; 770 clang_analyzer_eval(strncmp(x, "123", 3) == 0); // expected-warning{{TRUE}} 771} 772 773void strncmp_constant_and_var_1() { 774 char *x = "123"; 775 clang_analyzer_eval(strncmp("123", x, 3) == 0); // expected-warning{{TRUE}} 776} 777 778void strncmp_0() { 779 char *x = "123"; 780 char *y = "123"; 781 clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}} 782} 783 784void strncmp_1() { 785 char *x = "234"; 786 char *y = "123"; 787 clang_analyzer_eval(strncmp(x, y, 3) == 1); // expected-warning{{TRUE}} 788} 789 790void strncmp_2() { 791 char *x = "123"; 792 char *y = "234"; 793 clang_analyzer_eval(strncmp(x, y, 3) == -1); // expected-warning{{TRUE}} 794} 795 796void strncmp_null_0() { 797 char *x = NULL; 798 char *y = "123"; 799 strncmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}} 800} 801 802void strncmp_null_1() { 803 char *x = "123"; 804 char *y = NULL; 805 strncmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}} 806} 807 808void strncmp_diff_length_0() { 809 char *x = "12345"; 810 char *y = "234"; 811 clang_analyzer_eval(strncmp(x, y, 5) == -1); // expected-warning{{TRUE}} 812} 813 814void strncmp_diff_length_1() { 815 char *x = "123"; 816 char *y = "23456"; 817 clang_analyzer_eval(strncmp(x, y, 5) == -1); // expected-warning{{TRUE}} 818} 819 820void strncmp_diff_length_2() { 821 char *x = "12345"; 822 char *y = "123"; 823 clang_analyzer_eval(strncmp(x, y, 5) == 1); // expected-warning{{TRUE}} 824} 825 826void strncmp_diff_length_3() { 827 char *x = "123"; 828 char *y = "12345"; 829 clang_analyzer_eval(strncmp(x, y, 5) == -1); // expected-warning{{TRUE}} 830} 831 832void strncmp_diff_length_4() { 833 char *x = "123"; 834 char *y = "12345"; 835 clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}} 836} 837 838void strncmp_diff_length_5() { 839 char *x = "012"; 840 char *y = "12345"; 841 clang_analyzer_eval(strncmp(x, y, 3) == -1); // expected-warning{{TRUE}} 842} 843 844void strncmp_diff_length_6() { 845 char *x = "234"; 846 char *y = "12345"; 847 clang_analyzer_eval(strncmp(x, y, 3) == 1); // expected-warning{{TRUE}} 848} 849 850void strncmp_embedded_null () { 851 clang_analyzer_eval(strncmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}} 852} 853 854//===----------------------------------------------------------------------=== 855// strcasecmp() 856//===----------------------------------------------------------------------=== 857 858#define strcasecmp BUILTIN(strcasecmp) 859int strcasecmp(const char *s1, const char *s2); 860 861void strcasecmp_constant0() { 862 clang_analyzer_eval(strcasecmp("abc", "Abc") == 0); // expected-warning{{TRUE}} 863} 864 865void strcasecmp_constant_and_var_0() { 866 char *x = "abc"; 867 clang_analyzer_eval(strcasecmp(x, "Abc") == 0); // expected-warning{{TRUE}} 868} 869 870void strcasecmp_constant_and_var_1() { 871 char *x = "abc"; 872 clang_analyzer_eval(strcasecmp("Abc", x) == 0); // expected-warning{{TRUE}} 873} 874 875void strcasecmp_0() { 876 char *x = "abc"; 877 char *y = "Abc"; 878 clang_analyzer_eval(strcasecmp(x, y) == 0); // expected-warning{{TRUE}} 879} 880 881void strcasecmp_1() { 882 char *x = "Bcd"; 883 char *y = "abc"; 884 clang_analyzer_eval(strcasecmp(x, y) == 1); // expected-warning{{TRUE}} 885} 886 887void strcasecmp_2() { 888 char *x = "abc"; 889 char *y = "Bcd"; 890 clang_analyzer_eval(strcasecmp(x, y) == -1); // expected-warning{{TRUE}} 891} 892 893void strcasecmp_null_0() { 894 char *x = NULL; 895 char *y = "123"; 896 strcasecmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}} 897} 898 899void strcasecmp_null_1() { 900 char *x = "123"; 901 char *y = NULL; 902 strcasecmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}} 903} 904 905void strcasecmp_diff_length_0() { 906 char *x = "abcde"; 907 char *y = "aBd"; 908 clang_analyzer_eval(strcasecmp(x, y) == -1); // expected-warning{{TRUE}} 909} 910 911void strcasecmp_diff_length_1() { 912 char *x = "abc"; 913 char *y = "aBdef"; 914 clang_analyzer_eval(strcasecmp(x, y) == -1); // expected-warning{{TRUE}} 915} 916 917void strcasecmp_diff_length_2() { 918 char *x = "aBcDe"; 919 char *y = "abc"; 920 clang_analyzer_eval(strcasecmp(x, y) == 1); // expected-warning{{TRUE}} 921} 922 923void strcasecmp_diff_length_3() { 924 char *x = "aBc"; 925 char *y = "abcde"; 926 clang_analyzer_eval(strcasecmp(x, y) == -1); // expected-warning{{TRUE}} 927} 928 929void strcasecmp_embedded_null () { 930 clang_analyzer_eval(strcasecmp("ab\0zz", "ab\0yy") == 0); // expected-warning{{TRUE}} 931} 932 933//===----------------------------------------------------------------------=== 934// strncasecmp() 935//===----------------------------------------------------------------------=== 936 937#define strncasecmp BUILTIN(strncasecmp) 938int strncasecmp(const char *s1, const char *s2, size_t n); 939 940void strncasecmp_constant0() { 941 clang_analyzer_eval(strncasecmp("abc", "Abc", 3) == 0); // expected-warning{{TRUE}} 942} 943 944void strncasecmp_constant_and_var_0() { 945 char *x = "abc"; 946 clang_analyzer_eval(strncasecmp(x, "Abc", 3) == 0); // expected-warning{{TRUE}} 947} 948 949void strncasecmp_constant_and_var_1() { 950 char *x = "abc"; 951 clang_analyzer_eval(strncasecmp("Abc", x, 3) == 0); // expected-warning{{TRUE}} 952} 953 954void strncasecmp_0() { 955 char *x = "abc"; 956 char *y = "Abc"; 957 clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}} 958} 959 960void strncasecmp_1() { 961 char *x = "Bcd"; 962 char *y = "abc"; 963 clang_analyzer_eval(strncasecmp(x, y, 3) == 1); // expected-warning{{TRUE}} 964} 965 966void strncasecmp_2() { 967 char *x = "abc"; 968 char *y = "Bcd"; 969 clang_analyzer_eval(strncasecmp(x, y, 3) == -1); // expected-warning{{TRUE}} 970} 971 972void strncasecmp_null_0() { 973 char *x = NULL; 974 char *y = "123"; 975 strncasecmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}} 976} 977 978void strncasecmp_null_1() { 979 char *x = "123"; 980 char *y = NULL; 981 strncasecmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}} 982} 983 984void strncasecmp_diff_length_0() { 985 char *x = "abcde"; 986 char *y = "aBd"; 987 clang_analyzer_eval(strncasecmp(x, y, 5) == -1); // expected-warning{{TRUE}} 988} 989 990void strncasecmp_diff_length_1() { 991 char *x = "abc"; 992 char *y = "aBdef"; 993 clang_analyzer_eval(strncasecmp(x, y, 5) == -1); // expected-warning{{TRUE}} 994} 995 996void strncasecmp_diff_length_2() { 997 char *x = "aBcDe"; 998 char *y = "abc"; 999 clang_analyzer_eval(strncasecmp(x, y, 5) == 1); // expected-warning{{TRUE}} 1000} 1001 1002void strncasecmp_diff_length_3() { 1003 char *x = "aBc"; 1004 char *y = "abcde"; 1005 clang_analyzer_eval(strncasecmp(x, y, 5) == -1); // expected-warning{{TRUE}} 1006} 1007 1008void strncasecmp_diff_length_4() { 1009 char *x = "abcde"; 1010 char *y = "aBc"; 1011 clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}} 1012} 1013 1014void strncasecmp_diff_length_5() { 1015 char *x = "abcde"; 1016 char *y = "aBd"; 1017 clang_analyzer_eval(strncasecmp(x, y, 3) == -1); // expected-warning{{TRUE}} 1018} 1019 1020void strncasecmp_diff_length_6() { 1021 char *x = "aBDe"; 1022 char *y = "abc"; 1023 clang_analyzer_eval(strncasecmp(x, y, 3) == 1); // expected-warning{{TRUE}} 1024} 1025 1026void strncasecmp_embedded_null () { 1027 clang_analyzer_eval(strncasecmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}} 1028} 1029 1030//===----------------------------------------------------------------------=== 1031// FIXMEs 1032//===----------------------------------------------------------------------=== 1033 1034// The analyzer_eval call below should evaluate to true. We are being too 1035// aggressive in marking the (length of) src symbol dead. The length of dst 1036// depends on src. This could be explicitely specified in the checker or the 1037// logic for handling MetadataSymbol in SymbolManager needs to change. 1038void strcat_symbolic_src_length(char *src) { 1039 char dst[8] = "1234"; 1040 strcat(dst, src); 1041 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{UNKNOWN}} 1042} 1043 1044// The analyzer_eval call below should evaluate to true. Most likely the same 1045// issue as the test above. 1046void strncpy_exactly_matching_buffer2(char *y) { 1047 if (strlen(y) >= 4) 1048 return; 1049 1050 char x[4]; 1051 strncpy(x, y, 4); // no-warning 1052 1053 // This time, we know that y fits in x anyway. 1054 clang_analyzer_eval(strlen(x) <= 3); // expected-warning{{UNKNOWN}} 1055} 1056