1 // RUN: %clang_analyze_cc1 -analyzer-store=region -verify %s \ 2 // RUN: -analyzer-checker=core \ 3 // RUN: -analyzer-checker=alpha.deadcode.UnreachableCode \ 4 // RUN: -analyzer-checker=alpha.core.CastSize \ 5 // RUN: -analyzer-checker=unix \ 6 // RUN: -analyzer-checker=debug.ExprInspection 7 8 #include "Inputs/system-header-simulator.h" 9 10 void clang_analyzer_eval(int); 11 12 // Without -fms-compatibility, wchar_t isn't a builtin type. MSVC defines 13 // _WCHAR_T_DEFINED if wchar_t is available. Microsoft recommends that you use 14 // the builtin type: "Using the typedef version can cause portability 15 // problems", but we're ok here because we're not actually running anything. 16 // Also of note is this cryptic warning: "The wchar_t type is not supported 17 // when you compile C code". 18 // 19 // See the docs for more: 20 // https://msdn.microsoft.com/en-us/library/dh8che7s.aspx 21 #if !defined(_WCHAR_T_DEFINED) 22 // "Microsoft implements wchar_t as a two-byte unsigned value" 23 typedef unsigned short wchar_t; 24 #define _WCHAR_T_DEFINED 25 #endif // !defined(_WCHAR_T_DEFINED) 26 27 typedef __typeof(sizeof(int)) size_t; 28 void *malloc(size_t); 29 void *alloca(size_t); 30 void *valloc(size_t); 31 void free(void *); 32 void *realloc(void *ptr, size_t size); 33 void *reallocf(void *ptr, size_t size); 34 void *calloc(size_t nmemb, size_t size); 35 char *strdup(const char *s); 36 wchar_t *wcsdup(const wchar_t *s); 37 char *strndup(const char *s, size_t n); 38 int memcmp(const void *s1, const void *s2, size_t n); 39 40 // Windows variants 41 char *_strdup(const char *strSource); 42 wchar_t *_wcsdup(const wchar_t *strSource); 43 void *_alloca(size_t size); 44 45 void myfoo(int *p); 46 void myfooint(int p); 47 char *fooRetPtr(); 48 49 void f1() { 50 int *p = malloc(12); 51 return; // expected-warning{{Potential leak of memory pointed to by 'p'}} 52 } 53 54 void f2() { 55 int *p = malloc(12); 56 free(p); 57 free(p); // expected-warning{{Attempt to free released memory}} 58 } 59 60 void f2_realloc_0() { 61 int *p = malloc(12); 62 realloc(p,0); 63 realloc(p,0); // expected-warning{{Attempt to free released memory}} 64 } 65 66 void f2_realloc_1() { 67 int *p = malloc(12); 68 int *q = realloc(p,0); // no-warning 69 } 70 71 void reallocNotNullPtr(unsigned sizeIn) { 72 unsigned size = 12; 73 char *p = (char*)malloc(size); 74 if (p) { 75 char *q = (char*)realloc(p, sizeIn); 76 char x = *q; // expected-warning {{Potential leak of memory pointed to by 'q'}} 77 } 78 } 79 80 void allocaTest() { 81 int *p = alloca(sizeof(int)); 82 } // no warn 83 84 void winAllocaTest() { 85 int *p = _alloca(sizeof(int)); 86 } // no warn 87 88 void allocaBuiltinTest() { 89 int *p = __builtin_alloca(sizeof(int)); 90 } // no warn 91 92 int *realloctest1() { 93 int *q = malloc(12); 94 q = realloc(q, 20); 95 return q; // no warning - returning the allocated value 96 } 97 98 // p should be freed if realloc fails. 99 void reallocFails() { 100 char *p = malloc(12); 101 char *r = realloc(p, 12+1); 102 if (!r) { 103 free(p); 104 } else { 105 free(r); 106 } 107 } 108 109 void reallocSizeZero1() { 110 char *p = malloc(12); 111 char *r = realloc(p, 0); 112 if (!r) { 113 free(p); // expected-warning {{Attempt to free released memory}} 114 } else { 115 free(r); 116 } 117 } 118 119 void reallocSizeZero2() { 120 char *p = malloc(12); 121 char *r = realloc(p, 0); 122 if (!r) { 123 free(p); // expected-warning {{Attempt to free released memory}} 124 } else { 125 free(r); 126 } 127 free(p); // expected-warning {{Attempt to free released memory}} 128 } 129 130 void reallocSizeZero3() { 131 char *p = malloc(12); 132 char *r = realloc(p, 0); 133 free(r); 134 } 135 136 void reallocSizeZero4() { 137 char *r = realloc(0, 0); 138 free(r); 139 } 140 141 void reallocSizeZero5() { 142 char *r = realloc(0, 0); 143 } 144 145 void reallocPtrZero1() { 146 char *r = realloc(0, 12); 147 } // expected-warning {{Potential leak of memory pointed to by 'r'}} 148 149 void reallocPtrZero2() { 150 char *r = realloc(0, 12); 151 if (r) 152 free(r); 153 } 154 155 void reallocPtrZero3() { 156 char *r = realloc(0, 12); 157 free(r); 158 } 159 160 void reallocRadar6337483_1() { 161 char *buf = malloc(100); 162 buf = (char*)realloc(buf, 0x1000000); 163 if (!buf) { 164 return;// expected-warning {{Potential leak of memory pointed to by}} 165 } 166 free(buf); 167 } 168 169 void reallocRadar6337483_2() { 170 char *buf = malloc(100); 171 char *buf2 = (char*)realloc(buf, 0x1000000); 172 if (!buf2) { 173 ; 174 } else { 175 free(buf2); 176 } 177 } // expected-warning {{Potential leak of memory pointed to by}} 178 179 void reallocRadar6337483_3() { 180 char * buf = malloc(100); 181 char * tmp; 182 tmp = (char*)realloc(buf, 0x1000000); 183 if (!tmp) { 184 free(buf); 185 return; 186 } 187 buf = tmp; 188 free(buf); 189 } 190 191 void reallocRadar6337483_4() { 192 char *buf = malloc(100); 193 char *buf2 = (char*)realloc(buf, 0x1000000); 194 if (!buf2) { 195 return; // expected-warning {{Potential leak of memory pointed to by}} 196 } else { 197 free(buf2); 198 } 199 } 200 201 int *reallocfTest1() { 202 int *q = malloc(12); 203 q = reallocf(q, 20); 204 return q; // no warning - returning the allocated value 205 } 206 207 void reallocfRadar6337483_4() { 208 char *buf = malloc(100); 209 char *buf2 = (char*)reallocf(buf, 0x1000000); 210 if (!buf2) { 211 return; // no warning - reallocf frees even on failure 212 } else { 213 free(buf2); 214 } 215 } 216 217 void reallocfRadar6337483_3() { 218 char * buf = malloc(100); 219 char * tmp; 220 tmp = (char*)reallocf(buf, 0x1000000); 221 if (!tmp) { 222 free(buf); // expected-warning {{Attempt to free released memory}} 223 return; 224 } 225 buf = tmp; 226 free(buf); 227 } 228 229 void reallocfPtrZero1() { 230 char *r = reallocf(0, 12); 231 } // expected-warning {{Potential leak of memory pointed to by}} 232 233 //------------------- Check usage of zero-allocated memory --------------------- 234 void CheckUseZeroAllocatedNoWarn1() { 235 int *p = malloc(0); 236 free(p); // no warning 237 } 238 239 void CheckUseZeroAllocatedNoWarn2() { 240 int *p = alloca(0); // no warning 241 } 242 243 void CheckUseZeroWinAllocatedNoWarn2() { 244 int *p = _alloca(0); // no warning 245 } 246 247 248 void CheckUseZeroAllocatedNoWarn3() { 249 int *p = malloc(0); 250 int *q = realloc(p, 8); // no warning 251 free(q); 252 } 253 254 void CheckUseZeroAllocatedNoWarn4() { 255 int *p = realloc(0, 8); 256 *p = 1; // no warning 257 free(p); 258 } 259 260 void CheckUseZeroAllocated1() { 261 int *p = malloc(0); 262 *p = 1; // expected-warning {{Use of zero-allocated memory}} 263 free(p); 264 } 265 266 char CheckUseZeroAllocated2() { 267 char *p = alloca(0); 268 return *p; // expected-warning {{Use of zero-allocated memory}} 269 } 270 271 char CheckUseZeroWinAllocated2() { 272 char *p = _alloca(0); 273 return *p; // expected-warning {{Use of zero-allocated memory}} 274 } 275 276 void UseZeroAllocated(int *p) { 277 if (p) 278 *p = 7; // expected-warning {{Use of zero-allocated memory}} 279 } 280 void CheckUseZeroAllocated3() { 281 int *p = malloc(0); 282 UseZeroAllocated(p); 283 } 284 285 void f(char); 286 void CheckUseZeroAllocated4() { 287 char *p = valloc(0); 288 f(*p); // expected-warning {{Use of zero-allocated memory}} 289 free(p); 290 } 291 292 void CheckUseZeroAllocated5() { 293 int *p = calloc(0, 2); 294 *p = 1; // expected-warning {{Use of zero-allocated memory}} 295 free(p); 296 } 297 298 void CheckUseZeroAllocated6() { 299 int *p = calloc(2, 0); 300 *p = 1; // expected-warning {{Use of zero-allocated memory}} 301 free(p); 302 } 303 304 void CheckUseZeroAllocated7() { 305 int *p = realloc(0, 0); 306 *p = 1; // expected-warning {{Use of zero-allocated memory}} 307 free(p); 308 } 309 310 void CheckUseZeroAllocated8() { 311 int *p = malloc(8); 312 int *q = realloc(p, 0); 313 *q = 1; // expected-warning {{Use of zero-allocated memory}} 314 free(q); 315 } 316 317 void CheckUseZeroAllocated9() { 318 int *p = realloc(0, 0); 319 int *q = realloc(p, 0); 320 *q = 1; // expected-warning {{Use of zero-allocated memory}} 321 free(q); 322 } 323 324 void CheckUseZeroAllocatedPathNoWarn(_Bool b) { 325 int s = 0; 326 if (b) 327 s= 10; 328 329 char *p = malloc(s); 330 331 if (b) 332 *p = 1; // no warning 333 334 free(p); 335 } 336 337 void CheckUseZeroAllocatedPathWarn(_Bool b) { 338 int s = 10; 339 if (b) 340 s= 0; 341 342 char *p = malloc(s); 343 344 if (b) 345 *p = 1; // expected-warning {{Use of zero-allocated memory}} 346 347 free(p); 348 } 349 350 void CheckUseZeroReallocatedPathNoWarn(_Bool b) { 351 int s = 0; 352 if (b) 353 s= 10; 354 355 char *p = malloc(8); 356 char *q = realloc(p, s); 357 358 if (b) 359 *q = 1; // no warning 360 361 free(q); 362 } 363 364 void CheckUseZeroReallocatedPathWarn(_Bool b) { 365 int s = 10; 366 if (b) 367 s= 0; 368 369 char *p = malloc(8); 370 char *q = realloc(p, s); 371 372 if (b) 373 *q = 1; // expected-warning {{Use of zero-allocated memory}} 374 375 free(q); 376 } 377 378 // This case tests that storing malloc'ed memory to a static variable which is 379 // then returned is not leaked. In the absence of known contracts for functions 380 // or inter-procedural analysis, this is a conservative answer. 381 int *f3() { 382 static int *p = 0; 383 p = malloc(12); 384 return p; // no-warning 385 } 386 387 // This case tests that storing malloc'ed memory to a static global variable 388 // which is then returned is not leaked. In the absence of known contracts for 389 // functions or inter-procedural analysis, this is a conservative answer. 390 static int *p_f4 = 0; 391 int *f4() { 392 p_f4 = malloc(12); 393 return p_f4; // no-warning 394 } 395 396 int *f5() { 397 int *q = malloc(12); 398 q = realloc(q, 20); 399 return q; // no-warning 400 } 401 402 void f6() { 403 int *p = malloc(12); 404 if (!p) 405 return; // no-warning 406 else 407 free(p); 408 } 409 410 void f6_realloc() { 411 int *p = malloc(12); 412 if (!p) 413 return; // no-warning 414 else 415 realloc(p,0); 416 } 417 418 419 char *doit2(); 420 void pr6069() { 421 char *buf = doit2(); 422 free(buf); 423 } 424 425 void pr6293() { 426 free(0); 427 } 428 429 void f7() { 430 char *x = (char*) malloc(4); 431 free(x); 432 x[0] = 'a'; // expected-warning{{Use of memory after it is freed}} 433 } 434 435 void f8() { 436 char *x = (char*) malloc(4); 437 free(x); 438 char *y = strndup(x, 4); // expected-warning{{Use of memory after it is freed}} 439 } 440 441 void f7_realloc() { 442 char *x = (char*) malloc(4); 443 realloc(x,0); 444 x[0] = 'a'; // expected-warning{{Use of memory after it is freed}} 445 } 446 447 void PR6123() { 448 int *x = malloc(11); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 449 } 450 451 void PR7217() { 452 int *buf = malloc(2); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 453 buf[1] = 'c'; // not crash 454 } 455 456 void cast_emtpy_struct() { 457 struct st { 458 }; 459 460 struct st *s = malloc(sizeof(struct st)); // no-warning 461 free(s); 462 } 463 464 void cast_struct_1() { 465 struct st { 466 int i[100]; 467 char j[]; 468 }; 469 470 struct st *s = malloc(sizeof(struct st)); // no-warning 471 free(s); 472 } 473 474 void cast_struct_2() { 475 struct st { 476 int i[100]; 477 char j[0]; 478 }; 479 480 struct st *s = malloc(sizeof(struct st)); // no-warning 481 free(s); 482 } 483 484 void cast_struct_3() { 485 struct st { 486 int i[100]; 487 char j[1]; 488 }; 489 490 struct st *s = malloc(sizeof(struct st)); // no-warning 491 free(s); 492 } 493 494 void cast_struct_4() { 495 struct st { 496 int i[100]; 497 char j[2]; 498 }; 499 500 struct st *s = malloc(sizeof(struct st)); // no-warning 501 free(s); 502 } 503 504 void cast_struct_5() { 505 struct st { 506 char i[200]; 507 char j[1]; 508 }; 509 510 struct st *s = malloc(sizeof(struct st) - sizeof(char)); // no-warning 511 free(s); 512 } 513 514 void cast_struct_warn_1() { 515 struct st { 516 int i[100]; 517 char j[2]; 518 }; 519 520 struct st *s = malloc(sizeof(struct st) + 2); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 521 free(s); 522 } 523 524 void cast_struct_warn_2() { 525 struct st { 526 int i[100]; 527 char j[2]; 528 }; 529 530 struct st *s = malloc(2); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 531 free(s); 532 } 533 534 void cast_struct_flex_array_1() { 535 struct st { 536 int i[100]; 537 char j[]; 538 }; 539 540 struct st *s = malloc(sizeof(struct st) + 3); // no-warning 541 free(s); 542 } 543 544 void cast_struct_flex_array_2() { 545 struct st { 546 int i[100]; 547 char j[0]; 548 }; 549 550 struct st *s = malloc(sizeof(struct st) + 3); // no-warning 551 free(s); 552 } 553 554 void cast_struct_flex_array_3() { 555 struct st { 556 int i[100]; 557 char j[1]; 558 }; 559 560 struct st *s = malloc(sizeof(struct st) + 3); // no-warning 561 free(s); 562 } 563 564 void cast_struct_flex_array_4() { 565 struct foo { 566 char f[32]; 567 }; 568 struct st { 569 char i[100]; 570 struct foo data[]; 571 }; 572 573 struct st *s = malloc(sizeof(struct st) + 3 * sizeof(struct foo)); // no-warning 574 free(s); 575 } 576 577 void cast_struct_flex_array_5() { 578 struct foo { 579 char f[32]; 580 }; 581 struct st { 582 char i[100]; 583 struct foo data[0]; 584 }; 585 586 struct st *s = malloc(sizeof(struct st) + 3 * sizeof(struct foo)); // no-warning 587 free(s); 588 } 589 590 void cast_struct_flex_array_6() { 591 struct foo { 592 char f[32]; 593 }; 594 struct st { 595 char i[100]; 596 struct foo data[1]; 597 }; 598 599 struct st *s = malloc(sizeof(struct st) + 3 * sizeof(struct foo)); // no-warning 600 free(s); 601 } 602 603 void cast_struct_flex_array_warn_1() { 604 struct foo { 605 char f[32]; 606 }; 607 struct st { 608 char i[100]; 609 struct foo data[]; 610 }; 611 612 struct st *s = malloc(3 * sizeof(struct st) + 3 * sizeof(struct foo)); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 613 free(s); 614 } 615 616 void cast_struct_flex_array_warn_2() { 617 struct foo { 618 char f[32]; 619 }; 620 struct st { 621 char i[100]; 622 struct foo data[0]; 623 }; 624 625 struct st *s = malloc(3 * sizeof(struct st) + 3 * sizeof(struct foo)); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 626 free(s); 627 } 628 629 void cast_struct_flex_array_warn_3() { 630 struct foo { 631 char f[32]; 632 }; 633 struct st { 634 char i[100]; 635 struct foo data[1]; 636 }; 637 638 struct st *s = malloc(3 * sizeof(struct st) + 3 * sizeof(struct foo)); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 639 free(s); 640 } 641 642 void cast_struct_flex_array_warn_4() { 643 struct st { 644 int i[100]; 645 int j[]; 646 }; 647 648 struct st *s = malloc(sizeof(struct st) + 3); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 649 free(s); 650 } 651 652 void cast_struct_flex_array_warn_5() { 653 struct st { 654 int i[100]; 655 int j[0]; 656 }; 657 658 struct st *s = malloc(sizeof(struct st) + 3); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 659 free(s); 660 } 661 662 void cast_struct_flex_array_warn_6() { 663 struct st { 664 int i[100]; 665 int j[1]; 666 }; 667 668 struct st *s = malloc(sizeof(struct st) + 3); // expected-warning{{Cast a region whose size is not a multiple of the destination type size}} 669 free(s); 670 } 671 672 void mallocCastToVoid() { 673 void *p = malloc(2); 674 const void *cp = p; // not crash 675 free(p); 676 } 677 678 void mallocCastToFP() { 679 void *p = malloc(2); 680 void (*fp)() = p; // not crash 681 free(p); 682 } 683 684 // This tests that malloc() buffers are undefined by default 685 char mallocGarbage () { 686 char *buf = malloc(2); 687 char result = buf[1]; // expected-warning{{undefined}} 688 free(buf); 689 return result; 690 } 691 692 // This tests that calloc() buffers need to be freed 693 void callocNoFree () { 694 char *buf = calloc(2,2); 695 return; // expected-warning{{Potential leak of memory pointed to by 'buf'}} 696 } 697 698 // These test that calloc() buffers are zeroed by default 699 char callocZeroesGood () { 700 char *buf = calloc(2,2); 701 char result = buf[3]; // no-warning 702 if (buf[1] == 0) { 703 free(buf); 704 } 705 return result; // no-warning 706 } 707 708 char callocZeroesBad () { 709 char *buf = calloc(2,2); 710 char result = buf[3]; // no-warning 711 if (buf[1] != 0) { 712 free(buf); // expected-warning{{never executed}} 713 } 714 return result; // expected-warning{{Potential leak of memory pointed to by 'buf'}} 715 } 716 717 void nullFree() { 718 int *p = 0; 719 free(p); // no warning - a nop 720 } 721 722 void paramFree(int *p) { 723 myfoo(p); 724 free(p); // no warning 725 myfoo(p); // expected-warning {{Use of memory after it is freed}} 726 } 727 728 int* mallocEscapeRet() { 729 int *p = malloc(12); 730 return p; // no warning 731 } 732 733 void mallocEscapeFoo() { 734 int *p = malloc(12); 735 myfoo(p); 736 return; // no warning 737 } 738 739 void mallocEscapeFree() { 740 int *p = malloc(12); 741 myfoo(p); 742 free(p); 743 } 744 745 void mallocEscapeFreeFree() { 746 int *p = malloc(12); 747 myfoo(p); 748 free(p); 749 free(p); // expected-warning{{Attempt to free released memory}} 750 } 751 752 void mallocEscapeFreeUse() { 753 int *p = malloc(12); 754 myfoo(p); 755 free(p); 756 myfoo(p); // expected-warning{{Use of memory after it is freed}} 757 } 758 759 int *myalloc(); 760 void myalloc2(int **p); 761 762 void mallocEscapeFreeCustomAlloc() { 763 int *p = malloc(12); 764 myfoo(p); 765 free(p); 766 p = myalloc(); 767 free(p); // no warning 768 } 769 770 void mallocEscapeFreeCustomAlloc2() { 771 int *p = malloc(12); 772 myfoo(p); 773 free(p); 774 myalloc2(&p); 775 free(p); // no warning 776 } 777 778 void mallocBindFreeUse() { 779 int *x = malloc(12); 780 int *y = x; 781 free(y); 782 myfoo(x); // expected-warning{{Use of memory after it is freed}} 783 } 784 785 void mallocEscapeMalloc() { 786 int *p = malloc(12); 787 myfoo(p); 788 p = malloc(12); 789 } // expected-warning{{Potential leak of memory pointed to by}} 790 791 void mallocMalloc() { 792 int *p = malloc(12); 793 p = malloc(12); 794 } // expected-warning {{Potential leak of memory pointed to by}}\ 795 // expected-warning {{Potential leak of memory pointed to by}} 796 797 void mallocFreeMalloc() { 798 int *p = malloc(12); 799 free(p); 800 p = malloc(12); 801 free(p); 802 } 803 804 void mallocFreeUse_params() { 805 int *p = malloc(12); 806 free(p); 807 myfoo(p); //expected-warning{{Use of memory after it is freed}} 808 } 809 810 void mallocFreeUse_params2() { 811 int *p = malloc(12); 812 free(p); 813 myfooint(*p); //expected-warning{{Use of memory after it is freed}} 814 } 815 816 void mallocFailedOrNot() { 817 int *p = malloc(12); 818 if (!p) 819 free(p); 820 else 821 free(p); 822 } 823 824 struct StructWithInt { 825 int g; 826 }; 827 828 int *mallocReturnFreed() { 829 int *p = malloc(12); 830 free(p); 831 return p; // expected-warning {{Use of memory after it is freed}} 832 } 833 834 int useAfterFreeStruct() { 835 struct StructWithInt *px= malloc(sizeof(struct StructWithInt)); 836 px->g = 5; 837 free(px); 838 return px->g; // expected-warning {{Use of memory after it is freed}} 839 } 840 841 void nonSymbolAsFirstArg(int *pp, struct StructWithInt *p); 842 843 void mallocEscapeFooNonSymbolArg() { 844 struct StructWithInt *p = malloc(sizeof(struct StructWithInt)); 845 nonSymbolAsFirstArg(&p->g, p); 846 return; // no warning 847 } 848 849 void mallocFailedOrNotLeak() { 850 int *p = malloc(12); 851 if (p == 0) 852 return; // no warning 853 else 854 return; // expected-warning {{Potential leak of memory pointed to by}} 855 } 856 857 void mallocAssignment() { 858 char *p = malloc(12); 859 p = fooRetPtr(); 860 } // expected-warning {{leak}} 861 862 int vallocTest() { 863 char *mem = valloc(12); 864 return 0; // expected-warning {{Potential leak of memory pointed to by}} 865 } 866 867 void vallocEscapeFreeUse() { 868 int *p = valloc(12); 869 myfoo(p); 870 free(p); 871 myfoo(p); // expected-warning{{Use of memory after it is freed}} 872 } 873 874 int *Gl; 875 struct GlStTy { 876 int *x; 877 }; 878 879 struct GlStTy GlS = {0}; 880 881 void GlobalFree() { 882 free(Gl); 883 } 884 885 void GlobalMalloc() { 886 Gl = malloc(12); 887 } 888 889 void GlobalStructMalloc() { 890 int *a = malloc(12); 891 GlS.x = a; 892 } 893 894 void GlobalStructMallocFree() { 895 int *a = malloc(12); 896 GlS.x = a; 897 free(GlS.x); 898 } 899 900 char *ArrayG[12]; 901 902 void globalArrayTest() { 903 char *p = (char*)malloc(12); 904 ArrayG[0] = p; 905 } 906 907 // Make sure that we properly handle a pointer stored into a local struct/array. 908 typedef struct _StructWithPtr { 909 int *memP; 910 } StructWithPtr; 911 912 static StructWithPtr arrOfStructs[10]; 913 914 void testMalloc() { 915 int *x = malloc(12); 916 StructWithPtr St; 917 St.memP = x; 918 arrOfStructs[0] = St; // no-warning 919 } 920 921 StructWithPtr testMalloc2() { 922 int *x = malloc(12); 923 StructWithPtr St; 924 St.memP = x; 925 return St; // no-warning 926 } 927 928 int *testMalloc3() { 929 int *x = malloc(12); 930 int *y = x; 931 return y; // no-warning 932 } 933 934 void testStructLeak() { 935 StructWithPtr St; 936 St.memP = malloc(12); 937 return; // expected-warning {{Potential leak of memory pointed to by 'St.memP'}} 938 } 939 940 void testElemRegion1() { 941 char *x = (void*)malloc(2); 942 int *ix = (int*)x; 943 free(&(x[0])); 944 } 945 946 void testElemRegion2(int **pp) { 947 int *p = malloc(12); 948 *pp = p; 949 free(pp[0]); 950 } 951 952 void testElemRegion3(int **pp) { 953 int *p = malloc(12); 954 *pp = p; 955 free(*pp); 956 } 957 // Region escape testing. 958 959 unsigned takePtrToPtr(int **p); 960 void PassTheAddrOfAllocatedData(int f) { 961 int *p = malloc(12); 962 // We don't know what happens after the call. Should stop tracking here. 963 if (takePtrToPtr(&p)) 964 f++; 965 free(p); // no warning 966 } 967 968 struct X { 969 int *p; 970 }; 971 unsigned takePtrToStruct(struct X *s); 972 int ** foo2(int *g, int f) { 973 int *p = malloc(12); 974 struct X *px= malloc(sizeof(struct X)); 975 px->p = p; 976 // We don't know what happens after this call. Should not track px nor p. 977 if (takePtrToStruct(px)) 978 f++; 979 free(p); 980 return 0; 981 } 982 983 struct X* RegInvalidationDetect1(struct X *s2) { 984 struct X *px= malloc(sizeof(struct X)); 985 px->p = 0; 986 px = s2; 987 return px; // expected-warning {{Potential leak of memory pointed to by}} 988 } 989 990 struct X* RegInvalidationGiveUp1() { 991 int *p = malloc(12); 992 struct X *px= malloc(sizeof(struct X)); 993 px->p = p; 994 return px; 995 } 996 997 int **RegInvalidationDetect2(int **pp) { 998 int *p = malloc(12); 999 pp = &p; 1000 pp++; 1001 return 0;// expected-warning {{Potential leak of memory pointed to by}} 1002 } 1003 1004 extern void exit(int) __attribute__ ((__noreturn__)); 1005 void mallocExit(int *g) { 1006 struct xx *p = malloc(12); 1007 if (g != 0) 1008 exit(1); 1009 free(p); 1010 return; 1011 } 1012 1013 extern void __assert_fail (__const char *__assertion, __const char *__file, 1014 unsigned int __line, __const char *__function) 1015 __attribute__ ((__noreturn__)); 1016 #define assert(expr) \ 1017 ((expr) ? (void)(0) : __assert_fail (#expr, __FILE__, __LINE__, __func__)) 1018 void mallocAssert(int *g) { 1019 struct xx *p = malloc(12); 1020 1021 assert(g != 0); 1022 free(p); 1023 return; 1024 } 1025 1026 void doNotInvalidateWhenPassedToSystemCalls(char *s) { 1027 char *p = malloc(12); 1028 strlen(p); 1029 strcpy(p, s); 1030 strcpy(s, p); 1031 strcpy(p, p); 1032 memcpy(p, s, 1); 1033 memcpy(s, p, 1); 1034 memcpy(p, p, 1); 1035 } // expected-warning {{leak}} 1036 1037 // Treat source buffer contents as escaped. 1038 void escapeSourceContents(char *s) { 1039 char *p = malloc(12); 1040 memcpy(s, &p, 12); // no warning 1041 1042 void *p1 = malloc(7); 1043 char *a; 1044 memcpy(&a, &p1, sizeof a); 1045 // FIXME: No warning due to limitations imposed by current modelling of 1046 // 'memcpy' (regions metadata is not copied). 1047 1048 int *ptrs[2]; 1049 int *allocated = (int *)malloc(4); 1050 memcpy(&ptrs[0], &allocated, sizeof(int *)); 1051 // FIXME: No warning due to limitations imposed by current modelling of 1052 // 'memcpy' (regions metadata is not copied). 1053 } 1054 1055 void invalidateDestinationContents() { 1056 int *null = 0; 1057 int *p = (int *)malloc(4); 1058 memcpy(&p, &null, sizeof(int *)); 1059 1060 int *ptrs1[2]; // expected-warning {{Potential leak of memory pointed to by}} 1061 ptrs1[0] = (int *)malloc(4); 1062 memcpy(ptrs1, &null, sizeof(int *)); 1063 1064 int *ptrs2[2]; // expected-warning {{Potential memory leak}} 1065 ptrs2[0] = (int *)malloc(4); 1066 memcpy(&ptrs2[1], &null, sizeof(int *)); 1067 1068 int *ptrs3[2]; // expected-warning {{Potential memory leak}} 1069 ptrs3[0] = (int *)malloc(4); 1070 memcpy(&ptrs3[0], &null, sizeof(int *)); 1071 } // expected-warning {{Potential memory leak}} 1072 1073 // Rely on the CString checker evaluation of the strcpy API to convey that the result of strcpy is equal to p. 1074 void symbolLostWithStrcpy(char *s) { 1075 char *p = malloc(12); 1076 p = strcpy(p, s); 1077 free(p); 1078 } 1079 1080 1081 // The same test as the one above, but with what is actually generated on a mac. 1082 static __inline char * 1083 __inline_strcpy_chk (char *restrict __dest, const char *restrict __src) 1084 { 1085 return __builtin___strcpy_chk (__dest, __src, __builtin_object_size (__dest, 2 > 1)); 1086 } 1087 1088 void symbolLostWithStrcpy_InlineStrcpyVersion(char *s) { 1089 char *p = malloc(12); 1090 p = ((__builtin_object_size (p, 0) != (size_t) -1) ? __builtin___strcpy_chk (p, s, __builtin_object_size (p, 2 > 1)) : __inline_strcpy_chk (p, s)); 1091 free(p); 1092 } 1093 1094 // Here we are returning a pointer one past the allocated value. An idiom which 1095 // can be used for implementing special malloc. The correct uses of this might 1096 // be rare enough so that we could keep this as a warning. 1097 static void *specialMalloc(int n){ 1098 int *p; 1099 p = malloc( n+8 ); 1100 if( p ){ 1101 p[0] = n; 1102 p++; 1103 } 1104 return p; 1105 } 1106 1107 // Potentially, the user could free the struct by performing pointer arithmetic on the return value. 1108 // This is a variation of the specialMalloc issue, though probably would be more rare in correct code. 1109 int *specialMallocWithStruct() { 1110 struct StructWithInt *px= malloc(sizeof(struct StructWithInt)); 1111 return &(px->g); 1112 } 1113 1114 // Test various allocation/deallocation functions. 1115 void testStrdup(const char *s, unsigned validIndex) { 1116 char *s2 = strdup(s); 1117 s2[validIndex + 1] = 'b'; 1118 } // expected-warning {{Potential leak of memory pointed to by}} 1119 1120 void testWinStrdup(const char *s, unsigned validIndex) { 1121 char *s2 = _strdup(s); 1122 s2[validIndex + 1] = 'b'; 1123 } // expected-warning {{Potential leak of memory pointed to by}} 1124 1125 void testWcsdup(const wchar_t *s, unsigned validIndex) { 1126 wchar_t *s2 = wcsdup(s); 1127 s2[validIndex + 1] = 'b'; 1128 } // expected-warning {{Potential leak of memory pointed to by}} 1129 1130 void testWinWcsdup(const wchar_t *s, unsigned validIndex) { 1131 wchar_t *s2 = _wcsdup(s); 1132 s2[validIndex + 1] = 'b'; 1133 } // expected-warning {{Potential leak of memory pointed to by}} 1134 1135 int testStrndup(const char *s, unsigned validIndex, unsigned size) { 1136 char *s2 = strndup(s, size); 1137 s2 [validIndex + 1] = 'b'; 1138 if (s2[validIndex] != 'a') 1139 return 0; 1140 else 1141 return 1;// expected-warning {{Potential leak of memory pointed to by}} 1142 } 1143 1144 void testStrdupContentIsDefined(const char *s, unsigned validIndex) { 1145 char *s2 = strdup(s); 1146 char result = s2[1];// no warning 1147 free(s2); 1148 } 1149 1150 void testWinStrdupContentIsDefined(const char *s, unsigned validIndex) { 1151 char *s2 = _strdup(s); 1152 char result = s2[1];// no warning 1153 free(s2); 1154 } 1155 1156 void testWcsdupContentIsDefined(const wchar_t *s, unsigned validIndex) { 1157 wchar_t *s2 = wcsdup(s); 1158 wchar_t result = s2[1];// no warning 1159 free(s2); 1160 } 1161 1162 void testWinWcsdupContentIsDefined(const wchar_t *s, unsigned validIndex) { 1163 wchar_t *s2 = _wcsdup(s); 1164 wchar_t result = s2[1];// no warning 1165 free(s2); 1166 } 1167 1168 // ---------------------------------------------------------------------------- 1169 // Test the system library functions to which the pointer can escape. 1170 // This tests false positive suppression. 1171 1172 // For now, we assume memory passed to pthread_specific escapes. 1173 // TODO: We could check that if a new pthread binding is set, the existing 1174 // binding must be freed; otherwise, a memory leak can occur. 1175 void testPthereadSpecificEscape(pthread_key_t key) { 1176 void *buf = malloc(12); 1177 pthread_setspecific(key, buf); // no warning 1178 } 1179 1180 // PR12101: Test funopen(). 1181 static int releasePtr(void *_ctx) { 1182 free(_ctx); 1183 return 0; 1184 } 1185 FILE *useFunOpen() { 1186 void *ctx = malloc(sizeof(int)); 1187 FILE *f = funopen(ctx, 0, 0, 0, releasePtr); // no warning 1188 if (f == 0) { 1189 free(ctx); 1190 } 1191 return f; 1192 } 1193 FILE *useFunOpenNoReleaseFunction() { 1194 void *ctx = malloc(sizeof(int)); 1195 FILE *f = funopen(ctx, 0, 0, 0, 0); 1196 if (f == 0) { 1197 free(ctx); 1198 } 1199 return f; // expected-warning{{leak}} 1200 } 1201 1202 static int readNothing(void *_ctx, char *buf, int size) { 1203 return 0; 1204 } 1205 FILE *useFunOpenReadNoRelease() { 1206 void *ctx = malloc(sizeof(int)); 1207 FILE *f = funopen(ctx, readNothing, 0, 0, 0); 1208 if (f == 0) { 1209 free(ctx); 1210 } 1211 return f; // expected-warning{{leak}} 1212 } 1213 1214 // Test setbuf, setvbuf. 1215 int my_main_no_warning() { 1216 char *p = malloc(100); 1217 setvbuf(stdout, p, 0, 100); 1218 return 0; 1219 } 1220 int my_main_no_warning2() { 1221 char *p = malloc(100); 1222 setbuf(__stdoutp, p); 1223 return 0; 1224 } 1225 int my_main_warn(FILE *f) { 1226 char *p = malloc(100); 1227 setvbuf(f, p, 0, 100); 1228 return 0;// expected-warning {{leak}} 1229 } 1230 1231 // <rdar://problem/10978247>. 1232 // some people use stack allocated memory as an optimization to avoid 1233 // a heap allocation for small work sizes. This tests the analyzer's 1234 // understanding that the malloc'ed memory is not the same as stackBuffer. 1235 void radar10978247(int myValueSize) { 1236 char stackBuffer[128]; 1237 char *buffer; 1238 1239 if (myValueSize <= sizeof(stackBuffer)) 1240 buffer = stackBuffer; 1241 else 1242 buffer = malloc(myValueSize); 1243 1244 // do stuff with the buffer 1245 if (buffer != stackBuffer) 1246 free(buffer); 1247 } 1248 1249 void radar10978247_positive(int myValueSize) { 1250 char stackBuffer[128]; 1251 char *buffer; 1252 1253 if (myValueSize <= sizeof(stackBuffer)) 1254 buffer = stackBuffer; 1255 else 1256 buffer = malloc(myValueSize); 1257 1258 // do stuff with the buffer 1259 if (buffer == stackBuffer) 1260 return; 1261 else 1262 return; // expected-warning {{leak}} 1263 } 1264 // <rdar://problem/11269741> Previously this triggered a false positive 1265 // because malloc() is known to return uninitialized memory and the binding 1266 // of 'o' to 'p->n' was not getting propertly handled. Now we report a leak. 1267 struct rdar11269741_a_t { 1268 struct rdar11269741_b_t { 1269 int m; 1270 } n; 1271 }; 1272 1273 int rdar11269741(struct rdar11269741_b_t o) 1274 { 1275 struct rdar11269741_a_t *p = (struct rdar11269741_a_t *) malloc(sizeof(*p)); 1276 p->n = o; 1277 return p->n.m; // expected-warning {{leak}} 1278 } 1279 1280 // Pointer arithmetic, returning an ElementRegion. 1281 void *radar11329382(unsigned bl) { 1282 void *ptr = malloc (16); 1283 ptr = ptr + (2 - bl); 1284 return ptr; // no warning 1285 } 1286 1287 void __assert_rtn(const char *, const char *, int, const char *) __attribute__((__noreturn__)); 1288 int strcmp(const char *, const char *); 1289 char *a (void); 1290 void radar11270219(void) { 1291 char *x = a(), *y = a(); 1292 (__builtin_expect(!(x && y), 0) ? __assert_rtn(__func__, "/Users/zaks/tmp/ex.c", 24, "x && y") : (void)0); 1293 strcmp(x, y); // no warning 1294 } 1295 1296 void radar_11358224_test_double_assign_ints_positive_2() 1297 { 1298 void *ptr = malloc(16); 1299 ptr = ptr; 1300 } // expected-warning {{leak}} 1301 1302 // Assume that functions which take a function pointer can free memory even if 1303 // they are defined in system headers and take the const pointer to the 1304 // allocated memory. (radar://11160612) 1305 int const_ptr_and_callback(int, const char*, int n, void(*)(void*)); 1306 void r11160612_1() { 1307 char *x = malloc(12); 1308 const_ptr_and_callback(0, x, 12, free); // no - warning 1309 } 1310 1311 // Null is passed as callback. 1312 void r11160612_2() { 1313 char *x = malloc(12); 1314 const_ptr_and_callback(0, x, 12, 0); 1315 } // expected-warning {{leak}} 1316 1317 // Callback is passed to a function defined in a system header. 1318 void r11160612_4() { 1319 char *x = malloc(12); 1320 sqlite3_bind_text_my(0, x, 12, free); // no - warning 1321 } 1322 1323 // Passing callbacks in a struct. 1324 void r11160612_5(StWithCallback St) { 1325 void *x = malloc(12); 1326 dealocateMemWhenDoneByVal(x, St); 1327 } 1328 void r11160612_6(StWithCallback St) { 1329 void *x = malloc(12); 1330 dealocateMemWhenDoneByRef(&St, x); 1331 } 1332 1333 int mySub(int, int); 1334 int myAdd(int, int); 1335 int fPtr(unsigned cond, int x) { 1336 return (cond ? mySub : myAdd)(x, x); 1337 } 1338 1339 // Test anti-aliasing. 1340 1341 void dependsOnValueOfPtr(int *g, unsigned f) { 1342 int *p; 1343 1344 if (f) { 1345 p = g; 1346 } else { 1347 p = malloc(12); 1348 } 1349 1350 if (p != g) 1351 free(p); 1352 else 1353 return; // no warning 1354 return; 1355 } 1356 1357 int CMPRegionHeapToStack() { 1358 int x = 0; 1359 int *x1 = malloc(8); 1360 int *x2 = &x; 1361 clang_analyzer_eval(x1 == x2); // expected-warning{{FALSE}} 1362 free(x1); 1363 return x; 1364 } 1365 1366 int CMPRegionHeapToHeap2() { 1367 int x = 0; 1368 int *x1 = malloc(8); 1369 int *x2 = malloc(8); 1370 int *x4 = x1; 1371 int *x5 = x2; 1372 clang_analyzer_eval(x4 == x5); // expected-warning{{FALSE}} 1373 free(x1); 1374 free(x2); 1375 return x; 1376 } 1377 1378 int CMPRegionHeapToHeap() { 1379 int x = 0; 1380 int *x1 = malloc(8); 1381 int *x4 = x1; 1382 if (x1 == x4) { 1383 free(x1); 1384 return 5/x; // expected-warning{{Division by zero}} 1385 } 1386 return x;// expected-warning{{This statement is never executed}} 1387 } 1388 1389 int HeapAssignment() { 1390 int m = 0; 1391 int *x = malloc(4); 1392 int *y = x; 1393 *x = 5; 1394 clang_analyzer_eval(*x != *y); // expected-warning{{FALSE}} 1395 free(x); 1396 return 0; 1397 } 1398 1399 int *retPtr(); 1400 int *retPtrMightAlias(int *x); 1401 int cmpHeapAllocationToUnknown() { 1402 int zero = 0; 1403 int *yBefore = retPtr(); 1404 int *m = malloc(8); 1405 int *yAfter = retPtrMightAlias(m); 1406 clang_analyzer_eval(yBefore == m); // expected-warning{{FALSE}} 1407 clang_analyzer_eval(yAfter == m); // expected-warning{{FALSE}} 1408 free(m); 1409 return 0; 1410 } 1411 1412 void localArrayTest() { 1413 char *p = (char*)malloc(12); 1414 char *ArrayL[12]; 1415 ArrayL[0] = p; 1416 } // expected-warning {{leak}} 1417 1418 void localStructTest() { 1419 StructWithPtr St; 1420 StructWithPtr *pSt = &St; 1421 pSt->memP = malloc(12); 1422 } // expected-warning{{Potential leak of memory pointed to by}} 1423 1424 #ifdef __INTPTR_TYPE__ 1425 // Test double assignment through integers. 1426 typedef __INTPTR_TYPE__ intptr_t; 1427 typedef unsigned __INTPTR_TYPE__ uintptr_t; 1428 1429 static intptr_t glob; 1430 void test_double_assign_ints() 1431 { 1432 void *ptr = malloc (16); // no-warning 1433 glob = (intptr_t)(uintptr_t)ptr; 1434 } 1435 1436 void test_double_assign_ints_positive() 1437 { 1438 void *ptr = malloc(16); 1439 (void*)(intptr_t)(uintptr_t)ptr; // expected-warning {{unused}} 1440 } // expected-warning {{leak}} 1441 #endif 1442 1443 void testCGContextNoLeak() 1444 { 1445 void *ptr = malloc(16); 1446 CGContextRef context = CGBitmapContextCreate(ptr); 1447 1448 // Because you can get the data back out like this, even much later, 1449 // CGBitmapContextCreate is one of our "stop-tracking" exceptions. 1450 free(CGBitmapContextGetData(context)); 1451 } 1452 1453 void testCGContextLeak() 1454 { 1455 void *ptr = malloc(16); 1456 CGContextRef context = CGBitmapContextCreate(ptr); 1457 // However, this time we're just leaking the data, because the context 1458 // object doesn't escape and it hasn't been freed in this function. 1459 } 1460 1461 // Allow xpc context to escape. radar://11635258 1462 // TODO: Would be great if we checked that the finalize_connection_context actually releases it. 1463 static void finalize_connection_context(void *ctx) { 1464 int *context = ctx; 1465 free(context); 1466 } 1467 void foo (xpc_connection_t peer) { 1468 int *ctx = calloc(1, sizeof(int)); 1469 xpc_connection_set_context(peer, ctx); 1470 xpc_connection_set_finalizer_f(peer, finalize_connection_context); 1471 xpc_connection_resume(peer); 1472 } 1473 1474 // Make sure we catch errors when we free in a function which does not allocate memory. 1475 void freeButNoMalloc(int *p, int x){ 1476 if (x) { 1477 free(p); 1478 //user forgot a return here. 1479 } 1480 free(p); // expected-warning {{Attempt to free released memory}} 1481 } 1482 1483 struct HasPtr { 1484 char *p; 1485 }; 1486 1487 char* reallocButNoMalloc(struct HasPtr *a, int c, int size) { 1488 int *s; 1489 char *b = realloc(a->p, size); 1490 char *m = realloc(a->p, size); // expected-warning {{Attempt to free released memory}} 1491 // We don't expect a use-after-free for a->P here because the warning above 1492 // is a sink. 1493 return a->p; // no-warning 1494 } 1495 1496 // We should not warn in this case since the caller will presumably free a->p in all cases. 1497 int reallocButNoMallocPR13674(struct HasPtr *a, int c, int size) { 1498 int *s; 1499 char *b = realloc(a->p, size); 1500 if (b == 0) 1501 return -1; 1502 a->p = b; 1503 return 0; 1504 } 1505 1506 // Test realloc with no visible malloc. 1507 void *test(void *ptr) { 1508 void *newPtr = realloc(ptr, 4); 1509 if (newPtr == 0) { 1510 if (ptr) 1511 free(ptr); // no-warning 1512 } 1513 return newPtr; 1514 } 1515 1516 1517 char *testLeakWithinReturn(char *str) { 1518 return strdup(strdup(str)); // expected-warning{{leak}} 1519 } 1520 1521 char *testWinLeakWithinReturn(char *str) { 1522 return _strdup(_strdup(str)); // expected-warning{{leak}} 1523 } 1524 1525 wchar_t *testWinWideLeakWithinReturn(wchar_t *str) { 1526 return _wcsdup(_wcsdup(str)); // expected-warning{{leak}} 1527 } 1528 1529 void passConstPtr(const char * ptr); 1530 1531 void testPassConstPointer() { 1532 char * string = malloc(sizeof(char)*10); 1533 passConstPtr(string); 1534 return; // expected-warning {{leak}} 1535 } 1536 1537 void testPassConstPointerIndirectly() { 1538 char *p = malloc(1); 1539 p++; 1540 memcmp(p, p, sizeof(&p)); 1541 return; // expected-warning {{leak}} 1542 } 1543 1544 void testPassConstPointerIndirectlyStruct() { 1545 struct HasPtr hp; 1546 hp.p = malloc(10); 1547 memcmp(&hp, &hp, sizeof(hp)); 1548 return; // expected-warning {{Potential leak of memory pointed to by 'hp.p'}} 1549 } 1550 1551 void testPassToSystemHeaderFunctionIndirectlyStruct() { 1552 SomeStruct ss; 1553 ss.p = malloc(1); 1554 fakeSystemHeaderCall(&ss); // invalidates ss, making ss.p unreachable 1555 // Technically a false negative here -- we know the system function won't free 1556 // ss.p, but nothing else will either! 1557 } // no-warning 1558 1559 void testPassToSystemHeaderFunctionIndirectlyStructFree() { 1560 SomeStruct ss; 1561 ss.p = malloc(1); 1562 fakeSystemHeaderCall(&ss); // invalidates ss, making ss.p unreachable 1563 free(ss.p); 1564 } // no-warning 1565 1566 void testPassToSystemHeaderFunctionIndirectlyArray() { 1567 int *p[1]; 1568 p[0] = malloc(sizeof(int)); 1569 fakeSystemHeaderCallIntPtr(p); // invalidates p, making p[0] unreachable 1570 // Technically a false negative here -- we know the system function won't free 1571 // p[0], but nothing else will either! 1572 } // no-warning 1573 1574 void testPassToSystemHeaderFunctionIndirectlyArrayFree() { 1575 int *p[1]; 1576 p[0] = malloc(sizeof(int)); 1577 fakeSystemHeaderCallIntPtr(p); // invalidates p, making p[0] unreachable 1578 free(p[0]); 1579 } // no-warning 1580 1581 int *testOffsetAllocate(size_t size) { 1582 int *memoryBlock = (int *)malloc(size + sizeof(int)); 1583 return &memoryBlock[1]; // no-warning 1584 } 1585 1586 void testOffsetDeallocate(int *memoryBlock) { 1587 free(&memoryBlock[-1]); // no-warning 1588 } 1589 1590 void testOffsetOfRegionFreed() { 1591 __int64_t * array = malloc(sizeof(__int64_t)*2); 1592 array += 1; 1593 free(&array[0]); // expected-warning{{Argument to free() is offset by 8 bytes from the start of memory allocated by malloc()}} 1594 } 1595 1596 void testOffsetOfRegionFreed2() { 1597 __int64_t *p = malloc(sizeof(__int64_t)*2); 1598 p += 1; 1599 free(p); // expected-warning{{Argument to free() is offset by 8 bytes from the start of memory allocated by malloc()}} 1600 } 1601 1602 void testOffsetOfRegionFreed3() { 1603 char *r = malloc(sizeof(char)); 1604 r = r - 10; 1605 free(r); // expected-warning {{Argument to free() is offset by -10 bytes from the start of memory allocated by malloc()}} 1606 } 1607 1608 void testOffsetOfRegionFreedAfterFunctionCall() { 1609 int *p = malloc(sizeof(int)*2); 1610 p += 1; 1611 myfoo(p); 1612 free(p); // expected-warning{{Argument to free() is offset by 4 bytes from the start of memory allocated by malloc()}} 1613 } 1614 1615 void testFixManipulatedPointerBeforeFree() { 1616 int * array = malloc(sizeof(int)*2); 1617 array += 1; 1618 free(&array[-1]); // no-warning 1619 } 1620 1621 void testFixManipulatedPointerBeforeFree2() { 1622 char *r = malloc(sizeof(char)); 1623 r = r + 10; 1624 free(r-10); // no-warning 1625 } 1626 1627 void freeOffsetPointerPassedToFunction() { 1628 __int64_t *p = malloc(sizeof(__int64_t)*2); 1629 p[1] = 0; 1630 p += 1; 1631 myfooint(*p); // not passing the pointer, only a value pointed by pointer 1632 free(p); // expected-warning {{Argument to free() is offset by 8 bytes from the start of memory allocated by malloc()}} 1633 } 1634 1635 int arbitraryInt(); 1636 void freeUnknownOffsetPointer() { 1637 char *r = malloc(sizeof(char)); 1638 r = r + arbitraryInt(); // unable to reason about what the offset might be 1639 free(r); // no-warning 1640 } 1641 1642 void testFreeNonMallocPointerWithNoOffset() { 1643 char c; 1644 char *r = &c; 1645 r = r + 10; 1646 free(r-10); // expected-warning {{Argument to free() is the address of the local variable 'c', which is not memory allocated by malloc()}} 1647 } 1648 1649 void testFreeNonMallocPointerWithOffset() { 1650 char c; 1651 char *r = &c; 1652 free(r+1); // expected-warning {{Argument to free() is the address of the local variable 'c', which is not memory allocated by malloc()}} 1653 } 1654 1655 void testOffsetZeroDoubleFree() { 1656 int *array = malloc(sizeof(int)*2); 1657 int *p = &array[0]; 1658 free(p); 1659 free(&array[0]); // expected-warning{{Attempt to free released memory}} 1660 } 1661 1662 void testOffsetPassedToStrlen() { 1663 char * string = malloc(sizeof(char)*10); 1664 string += 1; 1665 int length = strlen(string); // expected-warning {{Potential leak of memory pointed to by 'string'}} 1666 } 1667 1668 void testOffsetPassedToStrlenThenFree() { 1669 char * string = malloc(sizeof(char)*10); 1670 string += 1; 1671 int length = strlen(string); 1672 free(string); // expected-warning {{Argument to free() is offset by 1 byte from the start of memory allocated by malloc()}} 1673 } 1674 1675 void testOffsetPassedAsConst() { 1676 char * string = malloc(sizeof(char)*10); 1677 string += 1; 1678 passConstPtr(string); 1679 free(string); // expected-warning {{Argument to free() is offset by 1 byte from the start of memory allocated by malloc()}} 1680 } 1681 1682 char **_vectorSegments; 1683 int _nVectorSegments; 1684 1685 void poolFreeC(void* s) { 1686 free(s); // no-warning 1687 } 1688 void freeMemory() { 1689 while (_nVectorSegments) { 1690 poolFreeC(_vectorSegments[_nVectorSegments++]); 1691 } 1692 } 1693 1694 // PR16730 1695 void testReallocEscaped(void **memory) { 1696 *memory = malloc(47); 1697 char *new_memory = realloc(*memory, 47); 1698 if (new_memory != 0) { 1699 *memory = new_memory; 1700 } 1701 } 1702 1703 // PR16558 1704 void *smallocNoWarn(size_t size) { 1705 if (size == 0) { 1706 return malloc(1); // this branch is never called 1707 } 1708 else { 1709 return malloc(size); 1710 } 1711 } 1712 1713 char *dupstrNoWarn(const char *s) { 1714 const int len = strlen(s); 1715 char *p = (char*) smallocNoWarn(len + 1); 1716 strcpy(p, s); // no-warning 1717 return p; 1718 } 1719 1720 void *smallocWarn(size_t size) { 1721 if (size == 2) { 1722 return malloc(1); 1723 } 1724 else { 1725 return malloc(size); 1726 } 1727 } 1728 1729 int *radar15580979() { 1730 int *data = (int *)malloc(32); 1731 int *p = data ?: (int*)malloc(32); // no warning 1732 return p; 1733 } 1734 1735 // Some data structures may hold onto the pointer and free it later. 1736 void testEscapeThroughSystemCallTakingVoidPointer1(void *queue) { 1737 int *data = (int *)malloc(32); 1738 fake_insque(queue, data); // no warning 1739 } 1740 1741 void testEscapeThroughSystemCallTakingVoidPointer2(fake_rb_tree_t *rbt) { 1742 int *data = (int *)malloc(32); 1743 fake_rb_tree_init(rbt, data); 1744 } //expected-warning{{Potential leak}} 1745 1746 void testEscapeThroughSystemCallTakingVoidPointer3(fake_rb_tree_t *rbt) { 1747 int *data = (int *)malloc(32); 1748 fake_rb_tree_init(rbt, data); 1749 fake_rb_tree_insert_node(rbt, data); // no warning 1750 } 1751 1752 struct IntAndPtr { 1753 int x; 1754 int *p; 1755 }; 1756 1757 void constEscape(const void *ptr); 1758 1759 void testConstEscapeThroughAnotherField() { 1760 struct IntAndPtr s; 1761 s.p = malloc(sizeof(int)); 1762 constEscape(&(s.x)); // could free s->p! 1763 } // no-warning 1764 1765 // PR15623 1766 int testNoCheckerDataPropogationFromLogicalOpOperandToOpResult(void) { 1767 char *param = malloc(10); 1768 char *value = malloc(10); 1769 int ok = (param && value); 1770 free(param); 1771 free(value); 1772 // Previously we ended up with 'Use of memory after it is freed' on return. 1773 return ok; // no warning 1774 } 1775 1776 void (*fnptr)(int); 1777 void freeIndirectFunctionPtr() { 1778 void *p = (void *)fnptr; 1779 free(p); // expected-warning {{Argument to free() is a function pointer}} 1780 } 1781 1782 void freeFunctionPtr() { 1783 free((void *)fnptr); // expected-warning {{Argument to free() is a function pointer}} 1784 } 1785 1786 void allocateSomeMemory(void *offendingParameter, void **ptr) { 1787 *ptr = malloc(1); 1788 } 1789 1790 void testNoCrashOnOffendingParameter() { 1791 // "extern" is necessary to avoid unrelated warnings 1792 // on passing uninitialized value. 1793 extern void *offendingParameter; 1794 void* ptr; 1795 allocateSomeMemory(offendingParameter, &ptr); 1796 } // expected-warning {{Potential leak of memory pointed to by 'ptr'}} 1797 1798 1799 // Test a false positive caused by a bug in liveness analysis. 1800 struct A { 1801 int *buf; 1802 }; 1803 struct B { 1804 struct A *a; 1805 }; 1806 void livenessBugRealloc(struct A *a) { 1807 a->buf = realloc(a->buf, sizeof(int)); // no-warning 1808 } 1809 void testLivenessBug(struct B *in_b) { 1810 struct B *b = in_b; 1811 livenessBugRealloc(b->a); 1812 ((void) 0); // An attempt to trick liveness analysis. 1813 livenessBugRealloc(b->a); 1814 } 1815 1816 struct ListInfo { 1817 struct ListInfo *next; 1818 }; 1819 1820 struct ConcreteListItem { 1821 struct ListInfo li; 1822 int i; 1823 }; 1824 1825 void list_add(struct ListInfo *list, struct ListInfo *item); 1826 1827 void testCStyleListItems(struct ListInfo *list) { 1828 struct ConcreteListItem *x = malloc(sizeof(struct ConcreteListItem)); 1829 list_add(list, &x->li); // will free 'x'. 1830 } 1831 1832 // MEM34-C. Only free memory allocated dynamically 1833 // Second non-compliant example. 1834 // https://wiki.sei.cmu.edu/confluence/display/c/MEM34-C.+Only+free+memory+allocated+dynamically 1835 enum { BUFSIZE = 256 }; 1836 1837 void MEM34_C(void) { 1838 char buf[BUFSIZE]; 1839 char *p = (char *)realloc(buf, 2 * BUFSIZE); 1840 // expected-warning@-1{{Argument to realloc() is the address of the local \ 1841 variable 'buf', which is not memory allocated by malloc() [unix.Malloc]}} 1842 if (p == NULL) { 1843 /* Handle error */ 1844 } 1845 } 1846 1847 (*crash_a)(); // expected-warning{{type specifier missing}} 1848 // A CallEvent without a corresponding FunctionDecl. 1849 crash_b() { crash_a(); } // no-crash 1850 // expected-warning@-1{{type specifier missing}} expected-warning@-1{{non-void}} 1851 1852 long *global_a; 1853 void realloc_crash() { 1854 long *c = global_a; 1855 c--; 1856 realloc(c, 8); // no-crash 1857 } // expected-warning{{Potential memory leak [unix.Malloc]}} 1858 1859 // ---------------------------------------------------------------------------- 1860 // False negatives. 1861 1862 void testMallocWithParam(int **p) { 1863 *p = (int*) malloc(sizeof(int)); 1864 *p = 0; // FIXME: should warn here 1865 } 1866 1867 void testMallocWithParam_2(int **p) { 1868 *p = (int*) malloc(sizeof(int)); // no-warning 1869 } 1870 1871 void testPassToSystemHeaderFunctionIndirectly() { 1872 int *p = malloc(4); 1873 p++; 1874 fakeSystemHeaderCallInt(p); 1875 // FIXME: This is a leak: if we think a system function won't free p, it 1876 // won't free (p-1) either. 1877 } 1878 1879 void testMallocIntoMalloc() { 1880 StructWithPtr *s = malloc(sizeof(StructWithPtr)); 1881 s->memP = malloc(sizeof(int)); 1882 free(s); 1883 } // FIXME: should warn here 1884