string.c revision 74c0d6988462c2cb882e7a8b8050fe119a5af56f
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 282void strcpy_effects(char *x, char *y) { 283 char a = x[0]; 284 285 clang_analyzer_eval(strcpy(x, y) == x); // expected-warning{{TRUE}} 286 clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}} 287 clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}} 288} 289 290void strcpy_overflow(char *y) { 291 char x[4]; 292 if (strlen(y) == 4) 293 strcpy(x, y); // expected-warning{{String copy function overflows destination buffer}} 294} 295 296void strcpy_no_overflow(char *y) { 297 char x[4]; 298 if (strlen(y) == 3) 299 strcpy(x, y); // no-warning 300} 301 302//===----------------------------------------------------------------------=== 303// stpcpy() 304//===----------------------------------------------------------------------=== 305 306#ifdef VARIANT 307 308#define __stpcpy_chk BUILTIN(__stpcpy_chk) 309char *__stpcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen); 310 311#define stpcpy(a,b) __stpcpy_chk(a,b,(size_t)-1) 312 313#else /* VARIANT */ 314 315#define stpcpy BUILTIN(stpcpy) 316char *stpcpy(char *restrict s1, const char *restrict s2); 317 318#endif /* VARIANT */ 319 320 321void stpcpy_effect(char *x, char *y) { 322 char a = x[0]; 323 324 clang_analyzer_eval(stpcpy(x, y) == &x[strlen(y)]); // expected-warning{{TRUE}} 325 clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}} 326 clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}} 327} 328 329void stpcpy_overflow(char *y) { 330 char x[4]; 331 if (strlen(y) == 4) 332 stpcpy(x, y); // expected-warning{{String copy function overflows destination buffer}} 333} 334 335void stpcpy_no_overflow(char *y) { 336 char x[4]; 337 if (strlen(y) == 3) 338 stpcpy(x, y); // no-warning 339} 340 341//===----------------------------------------------------------------------=== 342// strcat() 343//===----------------------------------------------------------------------=== 344 345#ifdef VARIANT 346 347#define __strcat_chk BUILTIN(__strcat_chk) 348char *__strcat_chk(char *restrict s1, const char *restrict s2, size_t destlen); 349 350#define strcat(a,b) __strcat_chk(a,b,(size_t)-1) 351 352#else /* VARIANT */ 353 354#define strcat BUILTIN(strcat) 355char *strcat(char *restrict s1, const char *restrict s2); 356 357#endif /* VARIANT */ 358 359 360void strcat_null_dst(char *x) { 361 strcat(NULL, x); // expected-warning{{Null pointer argument in call to string copy function}} 362} 363 364void strcat_null_src(char *x) { 365 strcat(x, NULL); // expected-warning{{Null pointer argument in call to string copy function}} 366} 367 368void strcat_fn(char *x) { 369 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}} 370} 371 372void strcat_effects(char *y) { 373 char x[8] = "123"; 374 size_t orig_len = strlen(x); 375 char a = x[0]; 376 377 if (strlen(y) != 4) 378 return; 379 380 clang_analyzer_eval(strcat(x, y) == x); // expected-warning{{TRUE}} 381 clang_analyzer_eval((int)strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}} 382} 383 384void strcat_overflow_0(char *y) { 385 char x[4] = "12"; 386 if (strlen(y) == 4) 387 strcat(x, y); // expected-warning{{String copy function overflows destination buffer}} 388} 389 390void strcat_overflow_1(char *y) { 391 char x[4] = "12"; 392 if (strlen(y) == 3) 393 strcat(x, y); // expected-warning{{String copy function overflows destination buffer}} 394} 395 396void strcat_overflow_2(char *y) { 397 char x[4] = "12"; 398 if (strlen(y) == 2) 399 strcat(x, y); // expected-warning{{String copy function overflows destination buffer}} 400} 401 402void strcat_no_overflow(char *y) { 403 char x[5] = "12"; 404 if (strlen(y) == 2) 405 strcat(x, y); // no-warning 406} 407 408void strcat_symbolic_dst_length(char *dst) { 409 strcat(dst, "1234"); 410 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 411} 412 413void strcat_symbolic_dst_length_taint(char *dst) { 414 scanf("%s", dst); // Taint data. 415 strcat(dst, "1234"); 416 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 417} 418 419void strcat_unknown_src_length(char *src, int offset) { 420 char dst[8] = "1234"; 421 strcat(dst, &src[offset]); 422 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 423} 424 425// There is no strcat_unknown_dst_length because if we can't get a symbolic 426// length for the "before" strlen, we won't be able to set one for "after". 427 428void strcat_too_big(char *dst, char *src) { 429 if (strlen(dst) != (((size_t)0) - 2)) 430 return; 431 if (strlen(src) != 2) 432 return; 433 strcat(dst, src); // expected-warning{{This expression will create a string whose length is too big to be represented as a size_t}} 434} 435 436 437//===----------------------------------------------------------------------=== 438// strncpy() 439//===----------------------------------------------------------------------=== 440 441#ifdef VARIANT 442 443#define __strncpy_chk BUILTIN(__strncpy_chk) 444char *__strncpy_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen); 445 446#define strncpy(a,b,n) __strncpy_chk(a,b,n,(size_t)-1) 447 448#else /* VARIANT */ 449 450#define strncpy BUILTIN(strncpy) 451char *strncpy(char *restrict s1, const char *restrict s2, size_t n); 452 453#endif /* VARIANT */ 454 455 456void strncpy_null_dst(char *x) { 457 strncpy(NULL, x, 5); // expected-warning{{Null pointer argument in call to string copy function}} 458} 459 460void strncpy_null_src(char *x) { 461 strncpy(x, NULL, 5); // expected-warning{{Null pointer argument in call to string copy function}} 462} 463 464void strncpy_fn(char *x) { 465 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}} 466} 467 468void strncpy_effects(char *x, char *y) { 469 char a = x[0]; 470 471 clang_analyzer_eval(strncpy(x, y, 5) == x); // expected-warning{{TRUE}} 472 clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{UNKNOWN}} 473 clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}} 474} 475 476void strncpy_overflow(char *y) { 477 char x[4]; 478 if (strlen(y) == 4) 479 strncpy(x, y, 5); // expected-warning{{Size argument is greater than the length of the destination buffer}} 480} 481 482void strncpy_no_overflow(char *y) { 483 char x[4]; 484 if (strlen(y) == 3) 485 strncpy(x, y, 5); // expected-warning{{Size argument is greater than the length of the destination buffer}} 486} 487 488void strncpy_no_overflow2(char *y, int n) { 489 if (n <= 4) 490 return; 491 492 char x[4]; 493 if (strlen(y) == 3) 494 strncpy(x, y, n); // expected-warning{{Size argument is greater than the length of the destination buffer}} 495} 496 497void strncpy_truncate(char *y) { 498 char x[4]; 499 if (strlen(y) == 4) 500 strncpy(x, y, 3); // no-warning 501} 502 503void strncpy_no_truncate(char *y) { 504 char x[4]; 505 if (strlen(y) == 3) 506 strncpy(x, y, 3); // no-warning 507} 508 509void strncpy_exactly_matching_buffer(char *y) { 510 char x[4]; 511 strncpy(x, y, 4); // no-warning 512 513 // strncpy does not null-terminate, so we have no idea what the strlen is 514 // after this. 515 clang_analyzer_eval(strlen(x) > 4); // expected-warning{{UNKNOWN}} 516} 517 518void strncpy_zero(char *src) { 519 char dst[] = "123"; 520 strncpy(dst, src, 0); // no-warning 521} 522 523void strncpy_empty() { 524 char dst[] = "123"; 525 char src[] = ""; 526 strncpy(dst, src, 4); // no-warning 527} 528 529//===----------------------------------------------------------------------=== 530// strncat() 531//===----------------------------------------------------------------------=== 532 533#ifdef VARIANT 534 535#define __strncat_chk BUILTIN(__strncat_chk) 536char *__strncat_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen); 537 538#define strncat(a,b,c) __strncat_chk(a,b,c, (size_t)-1) 539 540#else /* VARIANT */ 541 542#define strncat BUILTIN(strncat) 543char *strncat(char *restrict s1, const char *restrict s2, size_t n); 544 545#endif /* VARIANT */ 546 547 548void strncat_null_dst(char *x) { 549 strncat(NULL, x, 4); // expected-warning{{Null pointer argument in call to string copy function}} 550} 551 552void strncat_null_src(char *x) { 553 strncat(x, NULL, 4); // expected-warning{{Null pointer argument in call to string copy function}} 554} 555 556void strncat_fn(char *x) { 557 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}} 558} 559 560void strncat_effects(char *y) { 561 char x[8] = "123"; 562 size_t orig_len = strlen(x); 563 char a = x[0]; 564 565 if (strlen(y) != 4) 566 return; 567 568 clang_analyzer_eval(strncat(x, y, strlen(y)) == x); // expected-warning{{TRUE}} 569 clang_analyzer_eval(strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}} 570} 571 572void strncat_overflow_0(char *y) { 573 char x[4] = "12"; 574 if (strlen(y) == 4) 575 strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 576} 577 578void strncat_overflow_1(char *y) { 579 char x[4] = "12"; 580 if (strlen(y) == 3) 581 strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 582} 583 584void strncat_overflow_2(char *y) { 585 char x[4] = "12"; 586 if (strlen(y) == 2) 587 strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 588} 589 590void strncat_overflow_3(char *y) { 591 char x[4] = "12"; 592 if (strlen(y) == 4) 593 strncat(x, y, 2); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 594} 595void strncat_no_overflow_1(char *y) { 596 char x[5] = "12"; 597 if (strlen(y) == 2) 598 strncat(x, y, strlen(y)); // no-warning 599} 600 601void strncat_no_overflow_2(char *y) { 602 char x[4] = "12"; 603 if (strlen(y) == 4) 604 strncat(x, y, 1); // no-warning 605} 606 607void strncat_symbolic_dst_length(char *dst) { 608 strncat(dst, "1234", 5); 609 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 610} 611 612void strncat_symbolic_src_length(char *src) { 613 char dst[8] = "1234"; 614 strncat(dst, src, 3); 615 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 616 617 char dst2[8] = "1234"; 618 strncat(dst2, src, 4); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 619} 620 621void strncat_unknown_src_length(char *src, int offset) { 622 char dst[8] = "1234"; 623 strncat(dst, &src[offset], 3); 624 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 625 626 char dst2[8] = "1234"; 627 strncat(dst2, &src[offset], 4); // expected-warning{{Size argument is greater than the free space in the destination buffer}} 628} 629 630// There is no strncat_unknown_dst_length because if we can't get a symbolic 631// length for the "before" strlen, we won't be able to set one for "after". 632 633void strncat_symbolic_limit(unsigned limit) { 634 char dst[6] = "1234"; 635 char src[] = "567"; 636 strncat(dst, src, limit); // no-warning 637 638 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 639 clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}} 640} 641 642void strncat_unknown_limit(float limit) { 643 char dst[6] = "1234"; 644 char src[] = "567"; 645 strncat(dst, src, (size_t)limit); // no-warning 646 647 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}} 648 clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}} 649} 650 651void strncat_too_big(char *dst, char *src) { 652 if (strlen(dst) != (((size_t)0) - 2)) 653 return; 654 if (strlen(src) != 2) 655 return; 656 strncat(dst, src, 2); // expected-warning{{This expression will create a string whose length is too big to be represented as a size_t}} 657} 658 659void strncat_zero(char *src) { 660 char dst[] = "123"; 661 strncat(dst, src, 0); // no-warning 662} 663 664void strncat_empty() { 665 char dst[8] = "123"; 666 char src[] = ""; 667 strncat(dst, src, 4); // no-warning 668} 669 670//===----------------------------------------------------------------------=== 671// strcmp() 672//===----------------------------------------------------------------------=== 673 674#define strcmp BUILTIN(strcmp) 675int strcmp(const char * s1, const char * s2); 676 677void strcmp_constant0() { 678 clang_analyzer_eval(strcmp("123", "123") == 0); // expected-warning{{TRUE}} 679} 680 681void strcmp_constant_and_var_0() { 682 char *x = "123"; 683 clang_analyzer_eval(strcmp(x, "123") == 0); // expected-warning{{TRUE}} 684} 685 686void strcmp_constant_and_var_1() { 687 char *x = "123"; 688 clang_analyzer_eval(strcmp("123", x) == 0); // expected-warning{{TRUE}} 689} 690 691void strcmp_0() { 692 char *x = "123"; 693 char *y = "123"; 694 clang_analyzer_eval(strcmp(x, y) == 0); // expected-warning{{TRUE}} 695} 696 697void strcmp_1() { 698 char *x = "234"; 699 char *y = "123"; 700 clang_analyzer_eval(strcmp(x, y) == 1); // expected-warning{{TRUE}} 701} 702 703void strcmp_2() { 704 char *x = "123"; 705 char *y = "234"; 706 clang_analyzer_eval(strcmp(x, y) == -1); // expected-warning{{TRUE}} 707} 708 709void strcmp_null_0() { 710 char *x = NULL; 711 char *y = "123"; 712 strcmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}} 713} 714 715void strcmp_null_1() { 716 char *x = "123"; 717 char *y = NULL; 718 strcmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}} 719} 720 721void strcmp_diff_length_0() { 722 char *x = "12345"; 723 char *y = "234"; 724 clang_analyzer_eval(strcmp(x, y) == -1); // expected-warning{{TRUE}} 725} 726 727void strcmp_diff_length_1() { 728 char *x = "123"; 729 char *y = "23456"; 730 clang_analyzer_eval(strcmp(x, y) == -1); // expected-warning{{TRUE}} 731} 732 733void strcmp_diff_length_2() { 734 char *x = "12345"; 735 char *y = "123"; 736 clang_analyzer_eval(strcmp(x, y) == 1); // expected-warning{{TRUE}} 737} 738 739void strcmp_diff_length_3() { 740 char *x = "123"; 741 char *y = "12345"; 742 clang_analyzer_eval(strcmp(x, y) == -1); // expected-warning{{TRUE}} 743} 744 745void strcmp_embedded_null () { 746 clang_analyzer_eval(strcmp("\0z", "\0y") == 0); // expected-warning{{TRUE}} 747} 748 749void strcmp_unknown_arg (char *unknown) { 750 clang_analyzer_eval(strcmp(unknown, unknown) == 0); // expected-warning{{TRUE}} 751} 752 753//===----------------------------------------------------------------------=== 754// strncmp() 755//===----------------------------------------------------------------------=== 756 757#define strncmp BUILTIN(strncmp) 758int strncmp(const char *s1, const char *s2, size_t n); 759 760void strncmp_constant0() { 761 clang_analyzer_eval(strncmp("123", "123", 3) == 0); // expected-warning{{TRUE}} 762} 763 764void strncmp_constant_and_var_0() { 765 char *x = "123"; 766 clang_analyzer_eval(strncmp(x, "123", 3) == 0); // expected-warning{{TRUE}} 767} 768 769void strncmp_constant_and_var_1() { 770 char *x = "123"; 771 clang_analyzer_eval(strncmp("123", x, 3) == 0); // expected-warning{{TRUE}} 772} 773 774void strncmp_0() { 775 char *x = "123"; 776 char *y = "123"; 777 clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}} 778} 779 780void strncmp_1() { 781 char *x = "234"; 782 char *y = "123"; 783 clang_analyzer_eval(strncmp(x, y, 3) == 1); // expected-warning{{TRUE}} 784} 785 786void strncmp_2() { 787 char *x = "123"; 788 char *y = "234"; 789 clang_analyzer_eval(strncmp(x, y, 3) == -1); // expected-warning{{TRUE}} 790} 791 792void strncmp_null_0() { 793 char *x = NULL; 794 char *y = "123"; 795 strncmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}} 796} 797 798void strncmp_null_1() { 799 char *x = "123"; 800 char *y = NULL; 801 strncmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}} 802} 803 804void strncmp_diff_length_0() { 805 char *x = "12345"; 806 char *y = "234"; 807 clang_analyzer_eval(strncmp(x, y, 5) == -1); // expected-warning{{TRUE}} 808} 809 810void strncmp_diff_length_1() { 811 char *x = "123"; 812 char *y = "23456"; 813 clang_analyzer_eval(strncmp(x, y, 5) == -1); // expected-warning{{TRUE}} 814} 815 816void strncmp_diff_length_2() { 817 char *x = "12345"; 818 char *y = "123"; 819 clang_analyzer_eval(strncmp(x, y, 5) == 1); // expected-warning{{TRUE}} 820} 821 822void strncmp_diff_length_3() { 823 char *x = "123"; 824 char *y = "12345"; 825 clang_analyzer_eval(strncmp(x, y, 5) == -1); // expected-warning{{TRUE}} 826} 827 828void strncmp_diff_length_4() { 829 char *x = "123"; 830 char *y = "12345"; 831 clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}} 832} 833 834void strncmp_diff_length_5() { 835 char *x = "012"; 836 char *y = "12345"; 837 clang_analyzer_eval(strncmp(x, y, 3) == -1); // expected-warning{{TRUE}} 838} 839 840void strncmp_diff_length_6() { 841 char *x = "234"; 842 char *y = "12345"; 843 clang_analyzer_eval(strncmp(x, y, 3) == 1); // expected-warning{{TRUE}} 844} 845 846void strncmp_embedded_null () { 847 clang_analyzer_eval(strncmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}} 848} 849 850//===----------------------------------------------------------------------=== 851// strcasecmp() 852//===----------------------------------------------------------------------=== 853 854#define strcasecmp BUILTIN(strcasecmp) 855int strcasecmp(const char *s1, const char *s2); 856 857void strcasecmp_constant0() { 858 clang_analyzer_eval(strcasecmp("abc", "Abc") == 0); // expected-warning{{TRUE}} 859} 860 861void strcasecmp_constant_and_var_0() { 862 char *x = "abc"; 863 clang_analyzer_eval(strcasecmp(x, "Abc") == 0); // expected-warning{{TRUE}} 864} 865 866void strcasecmp_constant_and_var_1() { 867 char *x = "abc"; 868 clang_analyzer_eval(strcasecmp("Abc", x) == 0); // expected-warning{{TRUE}} 869} 870 871void strcasecmp_0() { 872 char *x = "abc"; 873 char *y = "Abc"; 874 clang_analyzer_eval(strcasecmp(x, y) == 0); // expected-warning{{TRUE}} 875} 876 877void strcasecmp_1() { 878 char *x = "Bcd"; 879 char *y = "abc"; 880 clang_analyzer_eval(strcasecmp(x, y) == 1); // expected-warning{{TRUE}} 881} 882 883void strcasecmp_2() { 884 char *x = "abc"; 885 char *y = "Bcd"; 886 clang_analyzer_eval(strcasecmp(x, y) == -1); // expected-warning{{TRUE}} 887} 888 889void strcasecmp_null_0() { 890 char *x = NULL; 891 char *y = "123"; 892 strcasecmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}} 893} 894 895void strcasecmp_null_1() { 896 char *x = "123"; 897 char *y = NULL; 898 strcasecmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}} 899} 900 901void strcasecmp_diff_length_0() { 902 char *x = "abcde"; 903 char *y = "aBd"; 904 clang_analyzer_eval(strcasecmp(x, y) == -1); // expected-warning{{TRUE}} 905} 906 907void strcasecmp_diff_length_1() { 908 char *x = "abc"; 909 char *y = "aBdef"; 910 clang_analyzer_eval(strcasecmp(x, y) == -1); // expected-warning{{TRUE}} 911} 912 913void strcasecmp_diff_length_2() { 914 char *x = "aBcDe"; 915 char *y = "abc"; 916 clang_analyzer_eval(strcasecmp(x, y) == 1); // expected-warning{{TRUE}} 917} 918 919void strcasecmp_diff_length_3() { 920 char *x = "aBc"; 921 char *y = "abcde"; 922 clang_analyzer_eval(strcasecmp(x, y) == -1); // expected-warning{{TRUE}} 923} 924 925void strcasecmp_embedded_null () { 926 clang_analyzer_eval(strcasecmp("ab\0zz", "ab\0yy") == 0); // expected-warning{{TRUE}} 927} 928 929//===----------------------------------------------------------------------=== 930// strncasecmp() 931//===----------------------------------------------------------------------=== 932 933#define strncasecmp BUILTIN(strncasecmp) 934int strncasecmp(const char *s1, const char *s2, size_t n); 935 936void strncasecmp_constant0() { 937 clang_analyzer_eval(strncasecmp("abc", "Abc", 3) == 0); // expected-warning{{TRUE}} 938} 939 940void strncasecmp_constant_and_var_0() { 941 char *x = "abc"; 942 clang_analyzer_eval(strncasecmp(x, "Abc", 3) == 0); // expected-warning{{TRUE}} 943} 944 945void strncasecmp_constant_and_var_1() { 946 char *x = "abc"; 947 clang_analyzer_eval(strncasecmp("Abc", x, 3) == 0); // expected-warning{{TRUE}} 948} 949 950void strncasecmp_0() { 951 char *x = "abc"; 952 char *y = "Abc"; 953 clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}} 954} 955 956void strncasecmp_1() { 957 char *x = "Bcd"; 958 char *y = "abc"; 959 clang_analyzer_eval(strncasecmp(x, y, 3) == 1); // expected-warning{{TRUE}} 960} 961 962void strncasecmp_2() { 963 char *x = "abc"; 964 char *y = "Bcd"; 965 clang_analyzer_eval(strncasecmp(x, y, 3) == -1); // expected-warning{{TRUE}} 966} 967 968void strncasecmp_null_0() { 969 char *x = NULL; 970 char *y = "123"; 971 strncasecmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}} 972} 973 974void strncasecmp_null_1() { 975 char *x = "123"; 976 char *y = NULL; 977 strncasecmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}} 978} 979 980void strncasecmp_diff_length_0() { 981 char *x = "abcde"; 982 char *y = "aBd"; 983 clang_analyzer_eval(strncasecmp(x, y, 5) == -1); // expected-warning{{TRUE}} 984} 985 986void strncasecmp_diff_length_1() { 987 char *x = "abc"; 988 char *y = "aBdef"; 989 clang_analyzer_eval(strncasecmp(x, y, 5) == -1); // expected-warning{{TRUE}} 990} 991 992void strncasecmp_diff_length_2() { 993 char *x = "aBcDe"; 994 char *y = "abc"; 995 clang_analyzer_eval(strncasecmp(x, y, 5) == 1); // expected-warning{{TRUE}} 996} 997 998void strncasecmp_diff_length_3() { 999 char *x = "aBc"; 1000 char *y = "abcde"; 1001 clang_analyzer_eval(strncasecmp(x, y, 5) == -1); // expected-warning{{TRUE}} 1002} 1003 1004void strncasecmp_diff_length_4() { 1005 char *x = "abcde"; 1006 char *y = "aBc"; 1007 clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}} 1008} 1009 1010void strncasecmp_diff_length_5() { 1011 char *x = "abcde"; 1012 char *y = "aBd"; 1013 clang_analyzer_eval(strncasecmp(x, y, 3) == -1); // expected-warning{{TRUE}} 1014} 1015 1016void strncasecmp_diff_length_6() { 1017 char *x = "aBDe"; 1018 char *y = "abc"; 1019 clang_analyzer_eval(strncasecmp(x, y, 3) == 1); // expected-warning{{TRUE}} 1020} 1021 1022void strncasecmp_embedded_null () { 1023 clang_analyzer_eval(strncasecmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}} 1024} 1025 1026//===----------------------------------------------------------------------=== 1027// FIXMEs 1028//===----------------------------------------------------------------------=== 1029 1030// The analyzer_eval call below should evaluate to true. We are being too 1031// aggressive in marking the (length of) src symbol dead. The length of dst 1032// depends on src. This could be explicitely specified in the checker or the 1033// logic for handling MetadataSymbol in SymbolManager needs to change. 1034void strcat_symbolic_src_length(char *src) { 1035 char dst[8] = "1234"; 1036 strcat(dst, src); 1037 clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{UNKNOWN}} 1038} 1039 1040// The analyzer_eval call below should evaluate to true. Most likely the same 1041// issue as the test above. 1042void strncpy_exactly_matching_buffer2(char *y) { 1043 if (strlen(y) >= 4) 1044 return; 1045 1046 char x[4]; 1047 strncpy(x, y, 4); // no-warning 1048 1049 // This time, we know that y fits in x anyway. 1050 clang_analyzer_eval(strlen(x) <= 3); // expected-warning{{UNKNOWN}} 1051} 1052