clang/test/Analysis/string.c

   1 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference \
   2 // RUN:   -analyzer-checker=core \
   3 // RUN:   -analyzer-checker=unix.cstring \
   4 // RUN:   -analyzer-checker=unix.Malloc \
   5 // RUN:   -analyzer-checker=alpha.unix.cstring \
   6 // RUN:   -analyzer-checker=debug.ExprInspection \
   7 // RUN:   -analyzer-config eagerly-assume=false
   8 //
   9 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference -DUSE_BUILTINS \
  10 // RUN:   -analyzer-checker=core \
  11 // RUN:   -analyzer-checker=unix.cstring \
  12 // RUN:   -analyzer-checker=unix.Malloc \
  13 // RUN:   -analyzer-checker=alpha.unix.cstring \
  14 // RUN:   -analyzer-checker=debug.ExprInspection \
  15 // RUN:   -analyzer-config eagerly-assume=false
  16 //
  17 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference -DVARIANT \
  18 // RUN:   -analyzer-checker=core \
  19 // RUN:   -analyzer-checker=unix.cstring \
  20 // RUN:   -analyzer-checker=unix.Malloc \
  21 // RUN:   -analyzer-checker=alpha.unix.cstring \
  22 // RUN:   -analyzer-checker=debug.ExprInspection \
  23 // RUN:   -analyzer-config eagerly-assume=false
  24 //
  25 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference \
  26 // RUN:   -DUSE_BUILTINS -DVARIANT \
  27 // RUN:   -analyzer-checker=core \
  28 // RUN:   -analyzer-checker=alpha.security.taint \
  29 // RUN:   -analyzer-checker=unix.cstring \
  30 // RUN:   -analyzer-checker=unix.Malloc \
  31 // RUN:   -analyzer-checker=alpha.unix.cstring \
  32 // RUN:   -analyzer-checker=debug.ExprInspection \
  33 // RUN:   -analyzer-config eagerly-assume=false
  34 //
  35 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference \
  36 // RUN:   -DSUPPRESS_OUT_OF_BOUND \
  37 // RUN:   -analyzer-checker=core \
  38 // RUN:   -analyzer-checker=unix.cstring \
  39 // RUN:   -analyzer-checker=unix.Malloc \
  40 // RUN:   -analyzer-checker=alpha.unix.cstring.BufferOverlap \
  41 // RUN:   -analyzer-checker=alpha.unix.cstring.NotNullTerminated \
  42 // RUN:   -analyzer-checker=debug.ExprInspection \
  43 // RUN:   -analyzer-config eagerly-assume=false
  44
  45 //===----------------------------------------------------------------------===
  46 // Declarations
  47 //===----------------------------------------------------------------------===
  48
  49 // Some functions are so similar to each other that they follow the same code
  50 // path, such as memcpy and __memcpy_chk, or memcmp and bcmp. If VARIANT is
  51 // defined, make sure to use the variants instead to make sure they are still
  52 // checked by the analyzer.
  53
  54 // Some functions are implemented as builtins. These should be #defined as
  55 // BUILTIN(f), which will prepend "__builtin_" if USE_BUILTINS is defined.
  56
  57 // Functions that have variants and are also available as builtins should be
  58 // declared carefully! See memcpy() for an example.
  59
  60 #ifdef USE_BUILTINS
  61 # define BUILTIN(f) __builtin_ ## f
  62 #else /* USE_BUILTINS */
  63 # define BUILTIN(f) f
  64 #endif /* USE_BUILTINS */
  65
  66 #define NULL 0
  67 typedef typeof(sizeof(int)) size_t;
  68
  69 void clang_analyzer_eval(int);
  70
  71 int scanf(const char *restrict format, ...);
  72 void *malloc(size_t);
  73 void free(void *);
  74 void *memcpy(void *restrict dest, const void *restrict src, size_t n);
  75
  76 //===----------------------------------------------------------------------===
  77 // strlen()
  78 //===----------------------------------------------------------------------===
  79
  80 #define strlen BUILTIN(strlen)
  81 size_t strlen(const char *s);
  82
  83 void strlen_constant0(void) {
  84   clang_analyzer_eval(strlen("123") == 3); // expected-warning{{TRUE}}
  85 }
  86
  87 void strlen_constant1(void) {
  88   const char *a = "123";
  89   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{TRUE}}
  90 }
  91
  92 void strlen_constant2(char x) {
  93   char a[] = "123";
  94   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{TRUE}}
  95
  96   a[0] = x;
  97   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{UNKNOWN}}
  98 }
  99
 100 const char *const global_str_ptr = "abcd";
 101 const char global_str_arr[] = "efgh";
 102 const char *global_non_const_ptr1 = "ijk";
 103 char *global_non_const_ptr2 = "lmn";
 104 char global_non_const_arr[] = "op";
 105
 106 void strlen_global_constant_ptr(void) {
 107   clang_analyzer_eval(strlen(global_str_ptr) == 4); // expected-warning{{TRUE}}
 108 }
 109
 110 void strlen_global_constant_arr(void) {
 111   clang_analyzer_eval(strlen(global_str_arr) == 4); // expected-warning{{TRUE}}
 112 }
 113
 114 void strlen_global_non_const_ptr(void) {
 115   clang_analyzer_eval(strlen(global_non_const_ptr1) == 3); // expected-warning{{UNKNOWN}}
 116   clang_analyzer_eval(strlen(global_non_const_ptr2) == 3); // expected-warning{{UNKNOWN}}
 117 }
 118
 119 void strlen_global_non_const_arr(void) {
 120   clang_analyzer_eval(strlen(global_non_const_arr) == 2); // expected-warning{{UNKNOWN}}
 121 }
 122
 123 size_t strlen_null(void) {
 124   return strlen(0); // expected-warning{{Null pointer passed as 1st argument to string length function}}
 125 }
 126
 127 size_t strlen_fn(void) {
 128   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}}
 129 }
 130
 131 size_t strlen_nonloc(void) {
 132 label:
 133   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}}
 134 }
 135
 136 void strlen_subregion(void) {
 137   struct two_strings { char a[2], b[2]; };
 138   extern void use_two_strings(struct two_strings *);
 139
 140   struct two_strings z;
 141   use_two_strings(&z);
 142
 143   size_t a = strlen(z.a);
 144   z.b[0] = 5;
 145   size_t b = strlen(z.a);
 146   if (a == 0)
 147     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
 148
 149   use_two_strings(&z);
 150
 151   size_t c = strlen(z.a);
 152   if (a == 0)
 153     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
 154 }
 155
 156 extern void use_string(char *);
 157 void strlen_argument(char *x) {
 158   size_t a = strlen(x);
 159   size_t b = strlen(x);
 160   if (a == 0)
 161     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
 162
 163   use_string(x);
 164
 165   size_t c = strlen(x);
 166   if (a == 0)
 167     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
 168 }
 169
 170 extern char global_str[];
 171 void strlen_global(void) {
 172   size_t a = strlen(global_str);
 173   size_t b = strlen(global_str);
 174   if (a == 0) {
 175     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
 176     // Make sure clang_analyzer_eval does not invalidate globals.
 177     clang_analyzer_eval(strlen(global_str) == 0); // expected-warning{{TRUE}}
 178   }
 179
 180   // Call a function with unknown effects, which should invalidate globals.
 181   use_string(0);
 182
 183   size_t c = strlen(global_str);
 184   if (a == 0)
 185     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
 186 }
 187
 188 void strlen_indirect(char *x) {
 189   size_t a = strlen(x);
 190   char *p = x;
 191   char **p2 = &p;
 192   size_t b = strlen(x);
 193   if (a == 0)
 194     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
 195
 196   extern void use_string_ptr(char*const*);
 197   use_string_ptr(p2);
 198
 199   size_t c = strlen(x);
 200   if (a == 0)
 201     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
 202 }
 203
 204 void strlen_indirect2(char *x) {
 205   size_t a = strlen(x);
 206   char *p = x;
 207   char **p2 = &p;
 208   extern void use_string_ptr2(char**);
 209   use_string_ptr2(p2);
 210
 211   size_t c = strlen(x);
 212   if (a == 0)
 213     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
 214 }
 215
 216 void strlen_liveness(const char *x) {
 217   if (strlen(x) < 5)
 218     return;
 219   clang_analyzer_eval(strlen(x) < 5); // expected-warning{{FALSE}}
 220 }
 221
 222
 223 size_t strlenWrapper(const char *str) {
 224   return strlen(str);
 225 }
 226
 227 extern void invalidate(char *s);
 228
 229 void testStrlenCallee(void) {
 230   char str[42];
 231   invalidate(str);
 232   size_t lenBefore = strlenWrapper(str);
 233   invalidate(str);
 234   size_t lenAfter = strlenWrapper(str);
 235   clang_analyzer_eval(lenBefore == lenAfter); // expected-warning{{UNKNOWN}}
 236 }
 237
 238
 239 //===----------------------------------------------------------------------===
 240 // strnlen()
 241 //===----------------------------------------------------------------------===
 242
 243 size_t strnlen(const char *s, size_t maxlen);
 244
 245 void strnlen_constant0(void) {
 246   clang_analyzer_eval(strnlen("123", 10) == 3); // expected-warning{{TRUE}}
 247 }
 248
 249 void strnlen_constant1(void) {
 250   const char *a = "123";
 251   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{TRUE}}
 252 }
 253
 254 void strnlen_constant2(char x) {
 255   char a[] = "123";
 256   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{TRUE}}
 257   a[0] = x;
 258   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{UNKNOWN}}
 259 }
 260
 261 void strnlen_constant4(void) {
 262   clang_analyzer_eval(strnlen("123456", 3) == 3); // expected-warning{{TRUE}}
 263 }
 264
 265 void strnlen_constant5(void) {
 266   const char *a = "123456";
 267   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{TRUE}}
 268 }
 269
 270 void strnlen_constant6(char x) {
 271   char a[] = "123456";
 272   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{TRUE}}
 273   a[0] = x;
 274   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{UNKNOWN}}
 275 }
 276
 277 size_t strnlen_null(void) {
 278   return strnlen(0, 3); // expected-warning{{Null pointer passed as 1st argument to string length function}}
 279 }
 280
 281 size_t strnlen_fn(void) {
 282   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}}
 283 }
 284
 285 size_t strnlen_nonloc(void) {
 286 label:
 287   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}}
 288 }
 289
 290 void strnlen_zero(void) {
 291   clang_analyzer_eval(strnlen("abc", 0) == 0); // expected-warning{{TRUE}}
 292   clang_analyzer_eval(strnlen(NULL, 0) == 0); // expected-warning{{TRUE}}
 293 }
 294
 295 size_t strnlen_compound_literal(void) {
 296   // This used to crash because we don't model the string lengths of
 297   // compound literals.
 298   return strnlen((char[]) { 'a', 'b', 0 }, 1);
 299 }
 300
 301 size_t strnlen_unknown_limit(float f) {
 302   // This used to crash because we don't model the integer values of floats.
 303   return strnlen("abc", (int)f);
 304 }
 305
 306 void strnlen_is_not_strlen(char *x) {
 307   clang_analyzer_eval(strnlen(x, 10) == strlen(x)); // expected-warning{{UNKNOWN}}
 308 }
 309
 310 void strnlen_at_limit(char *x) {
 311   size_t len = strnlen(x, 10);
 312   clang_analyzer_eval(len <= 10); // expected-warning{{TRUE}}
 313   clang_analyzer_eval(len == 10); // expected-warning{{UNKNOWN}}
 314   clang_analyzer_eval(len < 10); // expected-warning{{UNKNOWN}}
 315 }
 316
 317 void strnlen_at_actual(size_t limit) {
 318   size_t len = strnlen("abc", limit);
 319   clang_analyzer_eval(len <= 3); // expected-warning{{TRUE}}
 320   // This is due to eager assertion in strnlen.
 321   if (limit == 0) {
 322     clang_analyzer_eval(len == 0); // expected-warning{{TRUE}}
 323   } else {
 324     clang_analyzer_eval(len == 3); // expected-warning{{UNKNOWN}}
 325     clang_analyzer_eval(len < 3); // expected-warning{{UNKNOWN}}
 326   }
 327 }
 328
 329 //===----------------------------------------------------------------------===
 330 // strcpy()
 331 //===----------------------------------------------------------------------===
 332
 333 #ifdef VARIANT
 334
 335 #define __strcpy_chk BUILTIN(__strcpy_chk)
 336 char *__strcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen);
 337
 338 #define strcpy(a,b) __strcpy_chk(a,b,(size_t)-1)
 339
 340 #else /* VARIANT */
 341
 342 #define strcpy BUILTIN(strcpy)
 343 char *strcpy(char *restrict s1, const char *restrict s2);
 344
 345 #endif /* VARIANT */
 346
 347
 348 void strcpy_null_dst(char *x) {
 349   strcpy(NULL, x); // expected-warning{{Null pointer passed as 1st argument to string copy function}}
 350 }
 351
 352 void strcpy_null_src(char *x) {
 353   strcpy(x, NULL); // expected-warning{{Null pointer passed as 2nd argument to string copy function}}
 354 }
 355
 356 void strcpy_fn(char *x) {
 357   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}}
 358 }
 359
 360 void strcpy_fn_const(char *x) {
 361   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}}
 362 }
 363
 364 extern int globalInt;
 365 void strcpy_effects(char *x, char *y) {
 366   char a = x[0];
 367   if (globalInt != 42)
 368     return;
 369
 370   clang_analyzer_eval(strcpy(x, y) == x); // expected-warning{{TRUE}}
 371   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}}
 372   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
 373   clang_analyzer_eval(globalInt == 42); // expected-warning{{TRUE}}
 374 }
 375
 376 #ifndef SUPPRESS_OUT_OF_BOUND
 377 void strcpy_overflow(char *y) {
 378   char x[4];
 379   if (strlen(y) == 4)
 380     strcpy(x, y); // expected-warning{{String copy function overflows the destination buffer}}
 381 }
 382 #endif
 383
 384 void strcpy_no_overflow(char *y) {
 385   char x[4];
 386   if (strlen(y) == 3)
 387     strcpy(x, y); // no-warning
 388 }
 389
 390 // PR37503
 391 void *get_void_ptr(void);
 392 char ***type_punned_ptr;
 393 void strcpy_no_assertion(char c) {
 394   *(unsigned char **)type_punned_ptr = (unsigned char *)(get_void_ptr());
 395   strcpy(**type_punned_ptr, &c); // no-crash
 396 }
 397
 398 // PR49007
 399 char f(char ***c, int *i) {
 400   *(void **)c = i + 1;
 401   return (**c)[0]; // no-crash
 402 }
 403
 404 //===----------------------------------------------------------------------===
 405 // stpcpy()
 406 //===----------------------------------------------------------------------===
 407
 408 #ifdef VARIANT
 409
 410 #define __stpcpy_chk BUILTIN(__stpcpy_chk)
 411 char *__stpcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen);
 412
 413 #define stpcpy(a,b) __stpcpy_chk(a,b,(size_t)-1)
 414
 415 #else /* VARIANT */
 416
 417 #define stpcpy BUILTIN(stpcpy)
 418 char *stpcpy(char *restrict s1, const char *restrict s2);
 419
 420 #endif /* VARIANT */
 421
 422
 423 void stpcpy_effect(char *x, char *y) {
 424   char a = x[0];
 425
 426   clang_analyzer_eval(stpcpy(x, y) == &x[strlen(y)]); // expected-warning{{TRUE}}
 427   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}}
 428   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
 429 }
 430
 431 #ifndef SUPPRESS_OUT_OF_BOUND
 432 void stpcpy_overflow(char *y) {
 433   char x[4];
 434   if (strlen(y) == 4)
 435     stpcpy(x, y); // expected-warning{{String copy function overflows the destination buffer}}
 436 }
 437 #endif
 438
 439 void stpcpy_no_overflow(char *y) {
 440   char x[4];
 441   if (strlen(y) == 3)
 442     stpcpy(x, y); // no-warning
 443 }
 444
 445 //===----------------------------------------------------------------------===
 446 // strcat()
 447 //===----------------------------------------------------------------------===
 448
 449 #ifdef VARIANT
 450
 451 #define __strcat_chk BUILTIN(__strcat_chk)
 452 char *__strcat_chk(char *restrict s1, const char *restrict s2, size_t destlen);
 453
 454 #define strcat(a,b) __strcat_chk(a,b,(size_t)-1)
 455
 456 #else /* VARIANT */
 457
 458 #define strcat BUILTIN(strcat)
 459 char *strcat(char *restrict s1, const char *restrict s2);
 460
 461 #endif /* VARIANT */
 462
 463
 464 void strcat_null_dst(char *x) {
 465   strcat(NULL, x); // expected-warning{{Null pointer passed as 1st argument to string concatenation function}}
 466 }
 467
 468 void strcat_null_src(char *x) {
 469   strcat(x, NULL); // expected-warning{{Null pointer passed as 2nd argument to string concatenation function}}
 470 }
 471
 472 void strcat_fn(char *x) {
 473   strcat(x, (char*)&strcat_fn); // expected-warning{{Argument to string concatenation function is the address of the function 'strcat_fn', which is not a null-terminated string}}
 474 }
 475
 476 void strcat_effects(char *y) {
 477   char x[8] = "123";
 478   size_t orig_len = strlen(x);
 479   char a = x[0];
 480
 481   if (strlen(y) != 4)
 482     return;
 483
 484   clang_analyzer_eval(strcat(x, y) == x); // expected-warning{{TRUE}}
 485   clang_analyzer_eval((int)strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}}
 486 }
 487
 488 #ifndef SUPPRESS_OUT_OF_BOUND
 489 void strcat_overflow_0(char *y) {
 490   char x[4] = "12";
 491   if (strlen(y) == 4)
 492     strcat(x, y); // expected-warning{{String concatenation function overflows the destination buffer}}
 493 }
 494
 495 void strcat_overflow_1(char *y) {
 496   char x[4] = "12";
 497   if (strlen(y) == 3)
 498     strcat(x, y); // expected-warning{{String concatenation function overflows the destination buffer}}
 499 }
 500
 501 void strcat_overflow_2(char *y) {
 502   char x[4] = "12";
 503   if (strlen(y) == 2)
 504     strcat(x, y); // expected-warning{{String concatenation function overflows the destination buffer}}
 505 }
 506 #endif
 507
 508 void strcat_no_overflow(char *y) {
 509   char x[5] = "12";
 510   if (strlen(y) == 2)
 511     strcat(x, y); // no-warning
 512 }
 513
 514 void strcat_symbolic_dst_length(char *dst) {
 515         strcat(dst, "1234");
 516   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
 517 }
 518
 519 void strcat_symbolic_dst_length_taint(char *dst) {
 520   scanf("%s", dst); // Taint data.
 521   strcat(dst, "1234");
 522   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
 523 }
 524
 525 void strcat_unknown_src_length(char *src, int offset) {
 526         char dst[8] = "1234";
 527         strcat(dst, &src[offset]);
 528   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
 529 }
 530
 531 // There is no strcat_unknown_dst_length because if we can't get a symbolic
 532 // length for the "before" strlen, we won't be able to set one for "after".
 533
 534 void strcat_too_big(char *dst, char *src) {
 535   // We assume this can never actually happen, so we don't get a warning.
 536         if (strlen(dst) != (((size_t)0) - 2))
 537                 return;
 538         if (strlen(src) != 2)
 539                 return;
 540         strcat(dst, src);
 541 }
 542
 543
 544 //===----------------------------------------------------------------------===
 545 // strncpy()
 546 //===----------------------------------------------------------------------===
 547
 548 #ifdef VARIANT
 549
 550 #define __strncpy_chk BUILTIN(__strncpy_chk)
 551 char *__strncpy_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen);
 552
 553 #define strncpy(a,b,n) __strncpy_chk(a,b,n,(size_t)-1)
 554
 555 #else /* VARIANT */
 556
 557 #define strncpy BUILTIN(strncpy)
 558 char *strncpy(char *restrict s1, const char *restrict s2, size_t n);
 559
 560 #endif /* VARIANT */
 561
 562
 563 void strncpy_null_dst(char *x) {
 564   strncpy(NULL, x, 5); // expected-warning{{Null pointer passed as 1st argument to string copy function}}
 565 }
 566
 567 void strncpy_null_src(char *x) {
 568   strncpy(x, NULL, 5); // expected-warning{{Null pointer passed as 2nd argument to string copy function}}
 569 }
 570
 571 void strncpy_fn(char *x) {
 572   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}}
 573 }
 574
 575 void strncpy_effects(char *x, char *y) {
 576   char a = x[0];
 577
 578   clang_analyzer_eval(strncpy(x, y, 5) == x); // expected-warning{{TRUE}}
 579   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{UNKNOWN}}
 580   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
 581 }
 582
 583 #ifndef SUPPRESS_OUT_OF_BOUND
 584 // Enabling the malloc checker enables some of the buffer-checking portions
 585 // of the C-string checker.
 586 void cstringchecker_bounds_nocrash(void) {
 587   char *p = malloc(2);
 588   strncpy(p, "AAA", sizeof("AAA"));
 589   // expected-warning@-1 {{String copy function overflows the destination buffer}}
 590   free(p);
 591 }
 592
 593 void strncpy_overflow(char *y) {
 594   char x[4];
 595   if (strlen(y) == 4)
 596     strncpy(x, y, 5);
 597     // expected-warning@-1 {{String copy function overflows the destination buffer}}
 598 #ifndef VARIANT
 599     // expected-warning@-3 {{size argument is too large; destination buffer has size 4, but size argument is 5}}
 600 #endif
 601 }
 602
 603 void strncpy_no_overflow(char *y) {
 604   char x[4];
 605   if (strlen(y) == 3)
 606     strncpy(x, y, 5);
 607     // expected-warning@-1 {{String copy function overflows the destination buffer}}
 608 #ifndef VARIANT
 609     // expected-warning@-3 {{size argument is too large; destination buffer has size 4, but size argument is 5}}
 610 #endif
 611 }
 612
 613 void strncpy_no_overflow2(char *y, int n) {
 614         if (n <= 4)
 615                 return;
 616
 617   char x[4];
 618   if (strlen(y) == 3)
 619     strncpy(x, y, n);
 620   // expected-warning@-1 {{String copy function overflows the destination buffer}}
 621 }
 622 #endif
 623
 624 void strncpy_truncate(char *y) {
 625   char x[4];
 626   if (strlen(y) == 4)
 627     strncpy(x, y, 3); // no-warning
 628 }
 629
 630 void strncpy_no_truncate(char *y) {
 631   char x[4];
 632   if (strlen(y) == 3)
 633     strncpy(x, y, 3); // no-warning
 634 }
 635
 636 void strncpy_exactly_matching_buffer(char *y) {
 637         char x[4];
 638         strncpy(x, y, 4); // no-warning
 639
 640         // strncpy does not null-terminate, so we have no idea what the strlen is
 641         // after this.
 642   clang_analyzer_eval(strlen(x) > 4); // expected-warning{{UNKNOWN}}
 643 }
 644
 645 void strncpy_zero(char *src) {
 646   char dst[] = "123";
 647   strncpy(dst, src, 0); // no-warning
 648 }
 649
 650 void strncpy_empty(void) {
 651   char dst[] = "123";
 652   char src[] = "";
 653   strncpy(dst, src, 4); // no-warning
 654 }
 655
 656 //===----------------------------------------------------------------------===
 657 // strncat()
 658 //===----------------------------------------------------------------------===
 659
 660 #ifdef VARIANT
 661
 662 #define __strncat_chk BUILTIN(__strncat_chk)
 663 char *__strncat_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen);
 664
 665 #define strncat(a,b,c) __strncat_chk(a,b,c, (size_t)-1)
 666
 667 #else /* VARIANT */
 668
 669 #define strncat BUILTIN(strncat)
 670 char *strncat(char *restrict s1, const char *restrict s2, size_t n);
 671
 672 #endif /* VARIANT */
 673
 674
 675 void strncat_null_dst(char *x) {
 676   strncat(NULL, x, 4); // expected-warning{{Null pointer passed as 1st argument to string concatenation function}}
 677 }
 678
 679 void strncat_null_src(char *x) {
 680   strncat(x, NULL, 4); // expected-warning{{Null pointer passed as 2nd argument to string concatenation function}}
 681 }
 682
 683 void strncat_fn(char *x) {
 684   strncat(x, (char*)&strncat_fn, 4); // expected-warning{{Argument to string concatenation function is the address of the function 'strncat_fn', which is not a null-terminated string}}
 685 }
 686
 687 void strncat_effects(char *y) {
 688   char x[8] = "123";
 689   size_t orig_len = strlen(x);
 690   char a = x[0];
 691
 692   if (strlen(y) != 4)
 693     return;
 694
 695   clang_analyzer_eval(strncat(x, y, strlen(y)) == x); // expected-warning{{TRUE}}
 696   clang_analyzer_eval(strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}}
 697 }
 698
 699 #ifndef SUPPRESS_OUT_OF_BOUND
 700 void strncat_overflow_0(char *y) {
 701   char x[4] = "12";
 702   if (strlen(y) == 4)
 703     strncat(x, y, strlen(y));
 704   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
 705 }
 706
 707 void strncat_overflow_1(char *y) {
 708   char x[4] = "12";
 709   if (strlen(y) == 3)
 710     strncat(x, y, strlen(y));
 711   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
 712 }
 713
 714 void strncat_overflow_2(char *y) {
 715   char x[4] = "12";
 716   if (strlen(y) == 2)
 717     strncat(x, y, strlen(y));
 718   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
 719 }
 720
 721 void strncat_overflow_3(char *y) {
 722   char x[4] = "12";
 723   if (strlen(y) == 4)
 724     strncat(x, y, 2);
 725   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
 726 }
 727 #endif
 728
 729 void strncat_no_overflow_1(char *y) {
 730   char x[5] = "12";
 731   if (strlen(y) == 2)
 732     strncat(x, y, strlen(y)); // no-warning
 733 }
 734
 735 void strncat_no_overflow_2(char *y) {
 736   char x[4] = "12";
 737   if (strlen(y) == 4)
 738     strncat(x, y, 1); // no-warning
 739 }
 740
 741 void strncat_symbolic_dst_length(char *dst) {
 742   strncat(dst, "1234", 5);
 743   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
 744 }
 745
 746 #ifndef SUPPRESS_OUT_OF_BOUND
 747 void strncat_symbolic_src_length(char *src) {
 748   char dst[8] = "1234";
 749   strncat(dst, src, 3);
 750   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
 751
 752   char dst2[8] = "1234";
 753   strncat(dst2, src, 4);
 754   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
 755 }
 756
 757 void strncat_unknown_src_length(char *src, int offset) {
 758   char dst[8] = "1234";
 759   strncat(dst, &src[offset], 3);
 760   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
 761
 762   char dst2[8] = "1234";
 763   strncat(dst2, &src[offset], 4);
 764   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
 765 }
 766 #endif
 767
 768 // There is no strncat_unknown_dst_length because if we can't get a symbolic
 769 // length for the "before" strlen, we won't be able to set one for "after".
 770
 771 void strncat_symbolic_limit(unsigned limit) {
 772   char dst[6] = "1234";
 773   char src[] = "567";
 774   strncat(dst, src, limit); // no-warning
 775
 776   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
 777   clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}}
 778 }
 779
 780 void strncat_unknown_limit(float limit) {
 781   char dst[6] = "1234";
 782   char src[] = "567";
 783   strncat(dst, src, (size_t)limit); // no-warning
 784
 785   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
 786   clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}}
 787 }
 788
 789 void strncat_too_big(char *dst, char *src) {
 790   // We assume this will never actually happen, so we don't get a warning.
 791   if (strlen(dst) != (((size_t)0) - 2))
 792     return;
 793   if (strlen(src) != 2)
 794     return;
 795   strncat(dst, src, 2);
 796 }
 797
 798 void strncat_zero(char *src) {
 799   char dst[] = "123";
 800   strncat(dst, src, 0); // no-warning
 801 }
 802
 803 void strncat_empty(void) {
 804   char dst[8] = "123";
 805   char src[] = "";
 806   strncat(dst, src, 4); // no-warning
 807 }
 808
 809 //===----------------------------------------------------------------------===
 810 // strcmp()
 811 //===----------------------------------------------------------------------===
 812
 813 #define strcmp BUILTIN(strcmp)
 814 int strcmp(const char * s1, const char * s2);
 815
 816 void strcmp_check_modelling(void) {
 817   char *x = "aa";
 818   char *y = "a";
 819   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
 820   clang_analyzer_eval(strcmp(x, y) <= 0); // expected-warning{{FALSE}}
 821   clang_analyzer_eval(strcmp(x, y) > 1); // expected-warning{{UNKNOWN}}
 822
 823   clang_analyzer_eval(strcmp(y, x) < 0); // expected-warning{{TRUE}}
 824   clang_analyzer_eval(strcmp(y, x) >= 0); // expected-warning{{FALSE}}
 825   clang_analyzer_eval(strcmp(y, x) < -1); // expected-warning{{UNKNOWN}}
 826 }
 827
 828 void strcmp_constant0(void) {
 829   clang_analyzer_eval(strcmp("123", "123") == 0); // expected-warning{{TRUE}}
 830 }
 831
 832 void strcmp_constant_and_var_0(void) {
 833   char *x = "123";
 834   clang_analyzer_eval(strcmp(x, "123") == 0); // expected-warning{{TRUE}}
 835 }
 836
 837 void strcmp_constant_and_var_1(void) {
 838   char *x = "123";
 839   clang_analyzer_eval(strcmp("123", x) == 0); // expected-warning{{TRUE}}
 840 }
 841
 842 void strcmp_0(void) {
 843   char *x = "123";
 844   char *y = "123";
 845   clang_analyzer_eval(strcmp(x, y) == 0); // expected-warning{{TRUE}}
 846 }
 847
 848 void strcmp_1(void) {
 849   char *x = "234";
 850   char *y = "123";
 851   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
 852 }
 853
 854 void strcmp_2(void) {
 855   char *x = "123";
 856   char *y = "234";
 857   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
 858 }
 859
 860 void strcmp_null_0(void) {
 861   char *x = NULL;
 862   char *y = "123";
 863   strcmp(x, y); // expected-warning{{Null pointer passed as 1st argument to string comparison function}}
 864 }
 865
 866 void strcmp_null_1(void) {
 867   char *x = "123";
 868   char *y = NULL;
 869   strcmp(x, y); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
 870 }
 871
 872 void strcmp_diff_length_0(void) {
 873   char *x = "12345";
 874   char *y = "234";
 875   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
 876 }
 877
 878 void strcmp_diff_length_1(void) {
 879   char *x = "123";
 880   char *y = "23456";
 881   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
 882 }
 883
 884 void strcmp_diff_length_2(void) {
 885   char *x = "12345";
 886   char *y = "123";
 887   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
 888 }
 889
 890 void strcmp_diff_length_3(void) {
 891   char *x = "123";
 892   char *y = "12345";
 893   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
 894 }
 895
 896 void strcmp_embedded_null (void) {
 897         clang_analyzer_eval(strcmp("\0z", "\0y") == 0); // expected-warning{{TRUE}}
 898 }
 899
 900 void strcmp_unknown_arg (char *unknown) {
 901         clang_analyzer_eval(strcmp(unknown, unknown) == 0); // expected-warning{{TRUE}}
 902 }
 903
 904 union argument {
 905    char *f;
 906 };
 907
 908 void function_pointer_cast_helper(char **a) {
 909   strcmp("Hi", *a); // PR24951 crash
 910 }
 911
 912 void strcmp_union_function_pointer_cast(union argument a) {
 913   void (*fPtr)(union argument *) = (void (*)(union argument *))function_pointer_cast_helper;
 914
 915   fPtr(&a);
 916 }
 917
 918 int strcmp_null_argument(char *a) {
 919   char *b = 0;
 920   // Do not warn about the first argument!
 921   return strcmp(a, b); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
 922 }
 923
 924 //===----------------------------------------------------------------------===
 925 // strncmp()
 926 //===----------------------------------------------------------------------===
 927
 928 #define strncmp BUILTIN(strncmp)
 929 int strncmp(const char *s1, const char *s2, size_t n);
 930
 931 void strncmp_check_modelling(void) {
 932   char *x = "aa";
 933   char *y = "a";
 934   clang_analyzer_eval(strncmp(x, y, 2) > 0); // expected-warning{{TRUE}}
 935   clang_analyzer_eval(strncmp(x, y, 2) <= 0); // expected-warning{{FALSE}}
 936   clang_analyzer_eval(strncmp(x, y, 2) > 1); // expected-warning{{UNKNOWN}}
 937
 938   clang_analyzer_eval(strncmp(y, x, 2) < 0); // expected-warning{{TRUE}}
 939   clang_analyzer_eval(strncmp(y, x, 2) >= 0); // expected-warning{{FALSE}}
 940   clang_analyzer_eval(strncmp(y, x, 2) < -1); // expected-warning{{UNKNOWN}}
 941 }
 942
 943 void strncmp_constant0(void) {
 944   clang_analyzer_eval(strncmp("123", "123", 3) == 0); // expected-warning{{TRUE}}
 945 }
 946
 947 void strncmp_constant_and_var_0(void) {
 948   char *x = "123";
 949   clang_analyzer_eval(strncmp(x, "123", 3) == 0); // expected-warning{{TRUE}}
 950 }
 951
 952 void strncmp_constant_and_var_1(void) {
 953   char *x = "123";
 954   clang_analyzer_eval(strncmp("123", x, 3) == 0); // expected-warning{{TRUE}}
 955 }
 956
 957 void strncmp_0(void) {
 958   char *x = "123";
 959   char *y = "123";
 960   clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}}
 961 }
 962
 963 void strncmp_1(void) {
 964   char *x = "234";
 965   char *y = "123";
 966   clang_analyzer_eval(strncmp(x, y, 3) > 0); // expected-warning{{TRUE}}
 967 }
 968
 969 void strncmp_2(void) {
 970   char *x = "123";
 971   char *y = "234";
 972   clang_analyzer_eval(strncmp(x, y, 3) < 0); // expected-warning{{TRUE}}
 973 }
 974
 975 void strncmp_null_0(void) {
 976   char *x = NULL;
 977   char *y = "123";
 978   strncmp(x, y, 3); // expected-warning{{Null pointer passed as 1st argument to string comparison function}}
 979 }
 980
 981 void strncmp_null_1(void) {
 982   char *x = "123";
 983   char *y = NULL;
 984   strncmp(x, y, 3); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
 985 }
 986
 987 void strncmp_diff_length_0(void) {
 988   char *x = "12345";
 989   char *y = "234";
 990   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
 991 }
 992
 993 void strncmp_diff_length_1(void) {
 994   char *x = "123";
 995   char *y = "23456";
 996   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
 997 }
 998
 999 void strncmp_diff_length_2(void) {
1000   char *x = "12345";
1001   char *y = "123";
1002   clang_analyzer_eval(strncmp(x, y, 5) > 0); // expected-warning{{TRUE}}
1003 }
1004
1005 void strncmp_diff_length_3(void) {
1006   char *x = "123";
1007   char *y = "12345";
1008   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1009 }
1010
1011 void strncmp_diff_length_4(void) {
1012   char *x = "123";
1013   char *y = "12345";
1014   clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}}
1015 }
1016
1017 void strncmp_diff_length_5(void) {
1018   char *x = "012";
1019   char *y = "12345";
1020   clang_analyzer_eval(strncmp(x, y, 3) < 0); // expected-warning{{TRUE}}
1021 }
1022
1023 void strncmp_diff_length_6(void) {
1024   char *x = "234";
1025   char *y = "12345";
1026   clang_analyzer_eval(strncmp(x, y, 3) > 0); // expected-warning{{TRUE}}
1027 }
1028
1029 void strncmp_embedded_null (void) {
1030         clang_analyzer_eval(strncmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}}
1031 }
1032
1033 int strncmp_null_argument(char *a, size_t n) {
1034   char *b = 0;
1035   // Do not warn about the first argument!
1036   return strncmp(a, b, n); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1037 }
1038
1039 //===----------------------------------------------------------------------===
1040 // strcasecmp()
1041 //===----------------------------------------------------------------------===
1042
1043 #define strcasecmp BUILTIN(strcasecmp)
1044 int strcasecmp(const char *s1, const char *s2);
1045
1046 void strcasecmp_check_modelling(void) {
1047   char *x = "aa";
1048   char *y = "a";
1049   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
1050   clang_analyzer_eval(strcasecmp(x, y) <= 0); // expected-warning{{FALSE}}
1051   clang_analyzer_eval(strcasecmp(x, y) > 1); // expected-warning{{UNKNOWN}}
1052
1053   clang_analyzer_eval(strcasecmp(y, x) < 0); // expected-warning{{TRUE}}
1054   clang_analyzer_eval(strcasecmp(y, x) >= 0); // expected-warning{{FALSE}}
1055   clang_analyzer_eval(strcasecmp(y, x) < -1); // expected-warning{{UNKNOWN}}
1056 }
1057
1058 void strcasecmp_constant0(void) {
1059   clang_analyzer_eval(strcasecmp("abc", "Abc") == 0); // expected-warning{{TRUE}}
1060 }
1061
1062 void strcasecmp_constant_and_var_0(void) {
1063   char *x = "abc";
1064   clang_analyzer_eval(strcasecmp(x, "Abc") == 0); // expected-warning{{TRUE}}
1065 }
1066
1067 void strcasecmp_constant_and_var_1(void) {
1068   char *x = "abc";
1069   clang_analyzer_eval(strcasecmp("Abc", x) == 0); // expected-warning{{TRUE}}
1070 }
1071
1072 void strcasecmp_0(void) {
1073   char *x = "abc";
1074   char *y = "Abc";
1075   clang_analyzer_eval(strcasecmp(x, y) == 0); // expected-warning{{TRUE}}
1076 }
1077
1078 void strcasecmp_1(void) {
1079   char *x = "Bcd";
1080   char *y = "abc";
1081   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
1082 }
1083
1084 void strcasecmp_2(void) {
1085   char *x = "abc";
1086   char *y = "Bcd";
1087   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1088 }
1089
1090 void strcasecmp_null_0(void) {
1091   char *x = NULL;
1092   char *y = "123";
1093   strcasecmp(x, y); // expected-warning{{Null pointer passed as 1st argument to string comparison function}}
1094 }
1095
1096 void strcasecmp_null_1(void) {
1097   char *x = "123";
1098   char *y = NULL;
1099   strcasecmp(x, y); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1100 }
1101
1102 void strcasecmp_diff_length_0(void) {
1103   char *x = "abcde";
1104   char *y = "aBd";
1105   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1106 }
1107
1108 void strcasecmp_diff_length_1(void) {
1109   char *x = "abc";
1110   char *y = "aBdef";
1111   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1112 }
1113
1114 void strcasecmp_diff_length_2(void) {
1115   char *x = "aBcDe";
1116   char *y = "abc";
1117   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
1118 }
1119
1120 void strcasecmp_diff_length_3(void) {
1121   char *x = "aBc";
1122   char *y = "abcde";
1123   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1124 }
1125
1126 void strcasecmp_embedded_null (void) {
1127         clang_analyzer_eval(strcasecmp("ab\0zz", "ab\0yy") == 0); // expected-warning{{TRUE}}
1128 }
1129
1130 int strcasecmp_null_argument(char *a) {
1131   char *b = 0;
1132   // Do not warn about the first argument!
1133   return strcasecmp(a, b); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1134 }
1135
1136 //===----------------------------------------------------------------------===
1137 // strncasecmp()
1138 //===----------------------------------------------------------------------===
1139
1140 #define strncasecmp BUILTIN(strncasecmp)
1141 int strncasecmp(const char *s1, const char *s2, size_t n);
1142
1143 void strncasecmp_check_modelling(void) {
1144   char *x = "aa";
1145   char *y = "a";
1146   clang_analyzer_eval(strncasecmp(x, y, 2) > 0); // expected-warning{{TRUE}}
1147   clang_analyzer_eval(strncasecmp(x, y, 2) <= 0); // expected-warning{{FALSE}}
1148   clang_analyzer_eval(strncasecmp(x, y, 2) > 1); // expected-warning{{UNKNOWN}}
1149
1150   clang_analyzer_eval(strncasecmp(y, x, 2) < 0); // expected-warning{{TRUE}}
1151   clang_analyzer_eval(strncasecmp(y, x, 2) >= 0); // expected-warning{{FALSE}}
1152   clang_analyzer_eval(strncasecmp(y, x, 2) < -1); // expected-warning{{UNKNOWN}}
1153 }
1154
1155 void strncasecmp_constant0(void) {
1156   clang_analyzer_eval(strncasecmp("abc", "Abc", 3) == 0); // expected-warning{{TRUE}}
1157 }
1158
1159 void strncasecmp_constant_and_var_0(void) {
1160   char *x = "abc";
1161   clang_analyzer_eval(strncasecmp(x, "Abc", 3) == 0); // expected-warning{{TRUE}}
1162 }
1163
1164 void strncasecmp_constant_and_var_1(void) {
1165   char *x = "abc";
1166   clang_analyzer_eval(strncasecmp("Abc", x, 3) == 0); // expected-warning{{TRUE}}
1167 }
1168
1169 void strncasecmp_0(void) {
1170   char *x = "abc";
1171   char *y = "Abc";
1172   clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}}
1173 }
1174
1175 void strncasecmp_1(void) {
1176   char *x = "Bcd";
1177   char *y = "abc";
1178   clang_analyzer_eval(strncasecmp(x, y, 3) > 0); // expected-warning{{TRUE}}
1179 }
1180
1181 void strncasecmp_2(void) {
1182   char *x = "abc";
1183   char *y = "Bcd";
1184   clang_analyzer_eval(strncasecmp(x, y, 3) < 0); // expected-warning{{TRUE}}
1185 }
1186
1187 void strncasecmp_null_0(void) {
1188   char *x = NULL;
1189   char *y = "123";
1190   strncasecmp(x, y, 3); // expected-warning{{Null pointer passed as 1st argument to string comparison function}}
1191 }
1192
1193 void strncasecmp_null_1(void) {
1194   char *x = "123";
1195   char *y = NULL;
1196   strncasecmp(x, y, 3); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1197 }
1198
1199 void strncasecmp_diff_length_0(void) {
1200   char *x = "abcde";
1201   char *y = "aBd";
1202   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1203 }
1204
1205 void strncasecmp_diff_length_1(void) {
1206   char *x = "abc";
1207   char *y = "aBdef";
1208   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1209 }
1210
1211 void strncasecmp_diff_length_2(void) {
1212   char *x = "aBcDe";
1213   char *y = "abc";
1214   clang_analyzer_eval(strncasecmp(x, y, 5) > 0); // expected-warning{{TRUE}}
1215 }
1216
1217 void strncasecmp_diff_length_3(void) {
1218   char *x = "aBc";
1219   char *y = "abcde";
1220   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1221 }
1222
1223 void strncasecmp_diff_length_4(void) {
1224   char *x = "abcde";
1225   char *y = "aBc";
1226   clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}}
1227 }
1228
1229 void strncasecmp_diff_length_5(void) {
1230   char *x = "abcde";
1231   char *y = "aBd";
1232   clang_analyzer_eval(strncasecmp(x, y, 3) < 0); // expected-warning{{TRUE}}
1233 }
1234
1235 void strncasecmp_diff_length_6(void) {
1236   char *x = "aBDe";
1237   char *y = "abc";
1238   clang_analyzer_eval(strncasecmp(x, y, 3) > 0); // expected-warning{{TRUE}}
1239 }
1240
1241 void strncasecmp_embedded_null (void) {
1242         clang_analyzer_eval(strncasecmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}}
1243 }
1244
1245 int strncasecmp_null_argument(char *a, size_t n) {
1246   char *b = 0;
1247   // Do not warn about the first argument!
1248   return strncasecmp(a, b, n); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1249 }
1250
1251 //===----------------------------------------------------------------------===
1252 // strsep()
1253 //===----------------------------------------------------------------------===
1254
1255 char *strsep(char ** restrict stringp, const char * restrict delim);
1256
1257 void strsep_null_delim(char *s) {
1258   strsep(&s, NULL); // expected-warning{{Null pointer passed as 2nd argument to strsep()}}
1259 }
1260
1261 void strsep_null_search(void) {
1262   strsep(NULL, ""); // expected-warning{{Null pointer passed as 1st argument to strsep()}}
1263 }
1264
1265 void strsep_return_original_pointer(char *s) {
1266   char *original = s;
1267   char *result = strsep(&s, ""); // no-warning
1268   clang_analyzer_eval(original == result); // expected-warning{{TRUE}}
1269 }
1270
1271 void strsep_null_string(void) {
1272   char *s = NULL;
1273   char *result = strsep(&s, ""); // no-warning
1274   clang_analyzer_eval(result == NULL); // expected-warning{{TRUE}}
1275 }
1276
1277 void strsep_changes_input_pointer(char *s) {
1278   char *original = s;
1279   strsep(&s, ""); // no-warning
1280   clang_analyzer_eval(s == original); // expected-warning{{UNKNOWN}}
1281   clang_analyzer_eval(s == NULL); // expected-warning{{UNKNOWN}}
1282
1283   // Check that the value is symbolic.
1284   if (s == NULL) {
1285     clang_analyzer_eval(s == NULL); // expected-warning{{TRUE}}
1286   }
1287 }
1288
1289 void strsep_changes_input_string(void) {
1290   char str[] = "abc";
1291
1292   clang_analyzer_eval(str[1] == 'b'); // expected-warning{{TRUE}}
1293
1294   char *s = str;
1295   strsep(&s, "b"); // no-warning
1296
1297   // The real strsep will change the first delimiter it finds into a NUL
1298   // character. For now, we just model the invalidation.
1299   clang_analyzer_eval(str[1] == 'b'); // expected-warning{{UNKNOWN}}
1300 }
1301
1302 //===----------------------------------------------------------------------===
1303 // memset() / explicit_bzero() / bzero()
1304 //===----------------------------------------------------------------------===
1305
1306 void *memset(void *dest, int ch, size_t count);
1307
1308 void bzero(void *dst, size_t count);
1309 void explicit_bzero(void *dest, size_t count);
1310
1311 void *malloc(size_t size);
1312 void free(void *);
1313
1314 void memset1_char_array_null(void) {
1315   char str[] = "abcd";
1316   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1317   memset(str, '\0', 2);
1318   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1319 }
1320
1321 void memset2_char_array_null(void) {
1322   char str[] = "abcd";
1323   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1324   memset(str, '\0', strlen(str) + 1);
1325   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1326   clang_analyzer_eval(str[2] == 0);      // expected-warning{{TRUE}}
1327 }
1328
1329 void memset3_char_malloc_null(void) {
1330   char *str = (char *)malloc(10 * sizeof(char));
1331   memset(str + 1, '\0', 8);
1332   clang_analyzer_eval(str[1] == 0); // expected-warning{{UNKNOWN}}
1333   free(str);
1334 }
1335
1336 void memset4_char_malloc_null(void) {
1337   char *str = (char *)malloc(10 * sizeof(char));
1338   //void *str = malloc(10 * sizeof(char));
1339   memset(str, '\0', 10);
1340   clang_analyzer_eval(str[1] == 0);      // expected-warning{{TRUE}}
1341   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1342   free(str);
1343 }
1344
1345 #ifdef SUPPRESS_OUT_OF_BOUND
1346 void memset5_char_malloc_overflow_null(void) {
1347   char *str = (char *)malloc(10 * sizeof(char));
1348   memset(str, '\0', 12);
1349   clang_analyzer_eval(str[1] == 0); // expected-warning{{UNKNOWN}}
1350   free(str);
1351 }
1352 #endif
1353
1354 void memset6_char_array_nonnull(void) {
1355   char str[] = "abcd";
1356   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1357   memset(str, '0', 2);
1358   clang_analyzer_eval(str[0] == 'a');    // expected-warning{{UNKNOWN}}
1359   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{UNKNOWN}}
1360 }
1361
1362 #ifdef SUPPRESS_OUT_OF_BOUND
1363 void memset8_char_array_nonnull(void) {
1364   char str[5] = "abcd";
1365   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1366   memset(str, '0', 10); // expected-warning{{'memset' will always overflow; destination buffer has size 5, but size argument is 10}}
1367   clang_analyzer_eval(str[0] != '0');     // expected-warning{{UNKNOWN}}
1368   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1369   clang_analyzer_eval(strlen(str) < 10);  // expected-warning{{FALSE}}
1370 }
1371 #endif
1372
1373 struct POD_memset {
1374   int num;
1375   char c;
1376 };
1377
1378 void memset10_struct(void) {
1379   struct POD_memset pod;
1380   char *str = (char *)&pod;
1381   pod.num = 1;
1382   pod.c = 1;
1383   clang_analyzer_eval(pod.num == 0); // expected-warning{{FALSE}}
1384   memset(str, 0, sizeof(struct POD_memset));
1385   clang_analyzer_eval(pod.num == 0); // expected-warning{{TRUE}}
1386 }
1387
1388 #ifdef SUPPRESS_OUT_OF_BOUND
1389 void memset11_struct_field(void) {
1390   struct POD_memset pod;
1391   pod.num = 1;
1392   pod.c = '1';
1393   memset(&pod.num, 0, sizeof(struct POD_memset));
1394
1395   clang_analyzer_eval(pod.num == 0);  // expected-warning{{TRUE}}
1396   clang_analyzer_eval(pod.c == '\0'); // expected-warning{{TRUE}}
1397 }
1398
1399 void memset12_struct_field(void) {
1400   struct POD_memset pod;
1401   pod.num = 1;
1402   pod.c = '1';
1403   memset(&pod.c, 0, sizeof(struct POD_memset)); // expected-warning {{'memset' will always overflow; destination buffer has size 4, but size argument is 8}}
1404   clang_analyzer_eval(pod.num == 0); // expected-warning{{UNKNOWN}}
1405   clang_analyzer_eval(pod.c == 0);   // expected-warning{{UNKNOWN}}
1406 }
1407
1408 union U_memset {
1409   int i;
1410   double d;
1411   char c;
1412 };
1413
1414 void memset13_union_field(void) {
1415   union U_memset u;
1416   u.i = 5;
1417   memset(&u.i, '\0', sizeof(union U_memset));
1418   // Note: This should be TRUE, analyzer can't handle union perfectly now.
1419   clang_analyzer_eval(u.d == 0); // expected-warning{{UNKNOWN}}
1420 }
1421 #endif
1422
1423 void memset14_region_cast(void) {
1424   char *str = (char *)malloc(10 * sizeof(int));
1425   int *array = (int *)str;
1426   memset(array, 0, 10 * sizeof(int));
1427   clang_analyzer_eval(str[10] == '\0');            // expected-warning{{TRUE}}
1428   clang_analyzer_eval(strlen((char *)array) == 0); // expected-warning{{TRUE}}
1429   clang_analyzer_eval(strlen(str) == 0);           // expected-warning{{TRUE}}
1430   free(str);
1431 }
1432
1433 void memset15_region_cast(void) {
1434   char *str = (char *)malloc(10 * sizeof(int));
1435   int *array = (int *)str;
1436   memset(array, 0, 5 * sizeof(int));
1437   clang_analyzer_eval(str[10] == '\0');            // expected-warning{{UNKNOWN}}
1438   clang_analyzer_eval(strlen((char *)array) == 0); // expected-warning{{TRUE}}
1439   clang_analyzer_eval(strlen(str) == 0);           // expected-warning{{TRUE}}
1440   free(str);
1441 }
1442
1443 int memset20_scalar(void) {
1444   int *x = malloc(sizeof(int));
1445   *x = 10;
1446   memset(x, 0, sizeof(int));
1447   int num = 1 / *x; // expected-warning{{Division by zero}}
1448   free(x);
1449   return num;
1450 }
1451
1452 int memset21_scalar(void) {
1453   int *x = malloc(sizeof(int));
1454   memset(x, 0, 1);
1455   int num = 1 / *x;
1456   free(x);
1457   return num;
1458 }
1459
1460 void memset22_array(void) {
1461   int array[] = {1, 2, 3, 4, 5, 6, 7, 8, 9};
1462   clang_analyzer_eval(array[1] == 2); // expected-warning{{TRUE}}
1463   memset(array, 0, sizeof(array));
1464   clang_analyzer_eval(array[1] == 0); // expected-warning{{TRUE}}
1465 }
1466
1467 void memset23_array_pod_object(void) {
1468   struct POD_memset array[10];
1469   array[1].num = 10;
1470   array[1].c = 'c';
1471   clang_analyzer_eval(array[1].num == 10); // expected-warning{{TRUE}}
1472   memset(&array[1], 0, sizeof(struct POD_memset));
1473   clang_analyzer_eval(array[1].num == 0); // expected-warning{{UNKNOWN}}
1474 }
1475
1476 void memset24_array_pod_object(void) {
1477   struct POD_memset array[10];
1478   array[1].num = 10;
1479   array[1].c = 'c';
1480   clang_analyzer_eval(array[1].num == 10); // expected-warning{{TRUE}}
1481   memset(array, 0, sizeof(array));
1482   clang_analyzer_eval(array[1].num == 0); // expected-warning{{TRUE}}
1483 }
1484
1485 void memset25_symbol(char c) {
1486   char array[10] = {1};
1487   if (c != 0)
1488     return;
1489
1490   memset(array, c, 10);
1491
1492   clang_analyzer_eval(strlen(array) == 0); // expected-warning{{TRUE}}
1493   clang_analyzer_eval(array[4] == 0); // expected-warning{{TRUE}}
1494 }
1495
1496 void memset26_upper_UCHAR_MAX(void) {
1497   char array[10] = {1};
1498
1499   memset(array, 1024, 10);
1500
1501   clang_analyzer_eval(strlen(array) == 0); // expected-warning{{TRUE}}
1502   clang_analyzer_eval(array[4] == 0); // expected-warning{{TRUE}}
1503 }
1504
1505 void bzero1_null(void) {
1506   char *a = NULL;
1507
1508   bzero(a, 10); // expected-warning{{Null pointer passed as 1st argument to memory clearance function}}
1509 }
1510
1511 void bzero2_char_array_null(void) {
1512   char str[] = "abcd";
1513   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1514   bzero(str, 2);
1515   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1516 }
1517
1518 void bzero3_char_ptr_null(void) {
1519   char *str = "abcd";
1520   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1521   bzero(str + 2, 2);
1522   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{FALSE}}
1523 }
1524
1525 void explicit_bzero1_null(void) {
1526   char *a = NULL;
1527
1528   explicit_bzero(a, 10); // expected-warning{{Null pointer passed as 1st argument to memory clearance function}}
1529 }
1530
1531 void explicit_bzero2_clear_mypassword(void) {
1532   char passwd[7] = "passwd";
1533
1534   explicit_bzero(passwd, sizeof(passwd)); // no-warning
1535
1536   clang_analyzer_eval(strlen(passwd) == 0); // expected-warning{{TRUE}}
1537   clang_analyzer_eval(passwd[0] == '\0'); // expected-warning{{TRUE}}
1538 }
1539
1540 void explicit_bzero3_out_ofbound(void) {
1541   char *privkey = (char *)malloc(7);
1542   const char newprivkey[10] = "mysafekey";
1543
1544   strcpy(privkey, "random");
1545   explicit_bzero(privkey, sizeof(newprivkey));
1546 #ifndef SUPPRESS_OUT_OF_BOUND
1547   // expected-warning@-2 {{Memory clearance function overflows the destination buffer}}
1548 #endif
1549   clang_analyzer_eval(privkey[0] == '\0');
1550 #ifdef SUPPRESS_OUT_OF_BOUND
1551   // expected-warning@-2 {{UNKNOWN}}
1552 #endif
1553   free(privkey);
1554 }
1555
1556 //===----------------------------------------------------------------------===
1557 // FIXMEs
1558 //===----------------------------------------------------------------------===
1559
1560 // The analyzer_eval call below should evaluate to true. We are being too
1561 // aggressive in marking the (length of) src symbol dead. The length of dst
1562 // depends on src. This could be explicitly specified in the checker or the
1563 // logic for handling MetadataSymbol in SymbolManager needs to change.
1564 void strcat_symbolic_src_length(char *src) {
1565         char dst[8] = "1234";
1566         strcat(dst, src);
1567   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{UNKNOWN}}
1568 }
1569
1570
1571 // The analyzer_eval call below should evaluate to true. Most likely the same
1572 // issue as the test above.
1573 void strncpy_exactly_matching_buffer2(char *y) {
1574         if (strlen(y) >= 4)
1575                 return;
1576
1577         char x[4];
1578         strncpy(x, y, 4); // no-warning
1579
1580         // This time, we know that y fits in x anyway.
1581   clang_analyzer_eval(strlen(x) <= 3); // expected-warning{{UNKNOWN}}
1582 }
1583
1584 void memset7_char_array_nonnull(void) {
1585   char str[5] = "abcd";
1586   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1587   memset(str, '0', 5);
1588   // FIXME: This should be TRUE.
1589   clang_analyzer_eval(str[0] == '0');    // expected-warning{{UNKNOWN}}
1590   clang_analyzer_eval(strlen(str) >= 5); // expected-warning{{TRUE}}
1591 }
1592
1593 void memset16_region_cast(void) {
1594   char *str = (char *)malloc(10 * sizeof(int));
1595   int *array = (int *)str;
1596   memset(array, '0', 10 * sizeof(int));
1597   // FIXME: This should be TRUE.
1598   clang_analyzer_eval(str[10] == '0');                            // expected-warning{{UNKNOWN}}
1599   clang_analyzer_eval(strlen((char *)array) >= 10 * sizeof(int)); // expected-warning{{TRUE}}
1600   clang_analyzer_eval(strlen(str) >= 10 * sizeof(int));           // expected-warning{{TRUE}}
1601   free(str);
1602 }
1603
1604 #ifdef SUPPRESS_OUT_OF_BOUND
1605 void memset17_region_cast(void) {
1606   char *str = (char *)malloc(10 * sizeof(int));
1607   int *array = (int *)str;
1608   memset(array, '0', 12 * sizeof(int));
1609   clang_analyzer_eval(str[10] == '0');                            // expected-warning{{UNKNOWN}}
1610   clang_analyzer_eval(strlen((char *)array) >= 12 * sizeof(int)); // expected-warning{{TRUE}}
1611   clang_analyzer_eval(strlen(str) >= 12 * sizeof(int));           // expected-warning{{TRUE}}
1612   free(str);
1613 }
1614
1615 void memset18_memset_multiple_times(void) {
1616   char *str = (char *)malloc(10 * sizeof(char));
1617   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1618
1619   memset(str + 2, '\0', 10 * sizeof(char));
1620   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1621   clang_analyzer_eval(str[1] == '\0');   // expected-warning{{UNKNOWN}}
1622
1623   memset(str, '0', 10 * sizeof(char));
1624   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1625   // FIXME: This should be TRUE.
1626   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1627
1628   free(str);
1629 }
1630
1631 void memset19_memset_multiple_times(void) {
1632   char *str = (char *)malloc(10 * sizeof(char));
1633   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1634
1635   memset(str, '0', 10 * sizeof(char));
1636   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1637   // FIXME: This should be TRUE.
1638   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1639
1640   memset(str + 2, '\0', 10 * sizeof(char));
1641   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{UNKNOWN}}
1642   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1643
1644   free(str);
1645 }
1646 #endif
1647
1648 // The analyzer does not support binding a symbol with default binding.
1649 void memset27_symbol(char c) {
1650   char array[10] = {0};
1651   if (c < 10)
1652     return;
1653
1654   memset(array, c, 10);
1655
1656   clang_analyzer_eval(strlen(array) >= 10); // expected-warning{{TRUE}}
1657   // FIXME: This should be TRUE.
1658   clang_analyzer_eval(array[4] >= 10); // expected-warning{{UNKNOWN}}
1659 }
1660
1661 void memset28(void) {
1662   short x;
1663   memset(&x, 1, sizeof(short));
1664   // This should be true.
1665   clang_analyzer_eval(x == 0x101); // expected-warning{{UNKNOWN}}
1666 }
1667
1668 void memset29_plain_int_zero(void) {
1669   short x;
1670   memset(&x, 0, sizeof(short));
1671   clang_analyzer_eval(x == 0); // expected-warning{{TRUE}}
1672 }
1673
1674 void test_memset_chk(void) {
1675   int x;
1676   __builtin___memset_chk(&x, 0, sizeof(x), __builtin_object_size(&x, 0));
1677   clang_analyzer_eval(x == 0); // expected-warning{{TRUE}}
1678 }
1679
1680 #ifndef SUPPRESS_OUT_OF_BOUND
1681 void strcpy_no_overflow_2(char *y) {
1682   char x[3];
1683   // FIXME: string literal modeling does not account for embedded NULLs.
1684   //        This case should not elicit a warning, but does.
1685   //        See discussion at https://reviews.llvm.org/D129269
1686   strcpy(x, "12\0"); // expected-warning{{String copy function overflows the destination buffer}}
1687 }
1688 #else
1689 void strcpy_no_overflow_2(char *y) {
1690   char x[3];
1691   strcpy(x, "12\0");
1692 }
1693 #endif
1694
1695 #ifndef SUPPRESS_OUT_OF_BOUND
1696 void testStrcpyDestinationWritableFirstByte(void) {
1697   char dst[10];
1698   char *p = dst - 8;
1699   strcpy(p, "src"); // expected-warning {{String copy function overflows the destination buffer}}
1700 }
1701
1702 void CWE124_Buffer_Underwrite__malloc_char_cpy() {
1703   char * dataBuffer = (char *)malloc(100*sizeof(char));
1704   if (dataBuffer == NULL) return;
1705   memset(dataBuffer, 'A', 100-1);
1706   dataBuffer[100-1] = '\0';
1707   char * data = dataBuffer - 8;
1708   char source[100];
1709   memset(source, 'C', 100-1); // fill with 'C's
1710   source[100-1] = '\0'; // null terminate
1711   strcpy(data, source); // expected-warning {{String copy function overflows the destination buffer}}
1712   free(dataBuffer);
1713 }
1714 #endif
1715
1716 #ifndef SUPPRESS_OUT_OF_BOUND
1717 void testStrncpyDestinationWritableFirstByte(void) {
1718   char source[100];
1719   use_string(source); // escape
1720   char buf[100];
1721   char *p = buf - 8;
1722   strncpy(p, source, 100-1); // expected-warning {{String copy function overflows the destination buffer}}
1723 }
1724
1725 void CWE124_Buffer_Underwrite__malloc_char_ncpy() {
1726   char * dataBuffer = (char *)malloc(100*sizeof(char));
1727   if (dataBuffer == 0) return;
1728   memset(dataBuffer, 'A', 100-1);
1729   dataBuffer[100-1] = '\0';
1730   char *data = dataBuffer - 8;
1731
1732   char source[100];
1733   memset(source, 'C', 100-1); // fill with 'C's
1734   source[100-1] = '\0'; // null terminate
1735   strncpy(data, source, 100-1); // expected-warning {{String copy function overflows the destination buffer}}
1736   data[100-1] = '\0'; // null terminate
1737   free(dataBuffer);
1738 }
1739 #endif
1740
1741 #ifndef SUPPRESS_OUT_OF_BOUND
1742 void CWE124_Buffer_Underwrite__malloc_char_memcpy() {
1743   char * dataBuffer = (char *)malloc(100*sizeof(char));
1744   if (dataBuffer == NULL) return;
1745   memset(dataBuffer, 'A', 100-1);
1746   dataBuffer[100-1] = '\0';
1747   char *data = dataBuffer - 8;
1748
1749   char source[100];
1750   memset(source, 'C', 100-1); // fill with 'C's
1751   source[100-1] = '\0'; // null terminate
1752
1753   memcpy(data, source, 100*sizeof(char)); // expected-warning {{Memory copy function overflows the destination buffer}}
1754   data[100-1] = '\0';
1755   free(dataBuffer);
1756 }
1757 #endif