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