1 //===-- dfsan.cc ----------------------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is a part of DataFlowSanitizer.
12 // This file defines the custom functions listed in done_abilist.txt.
13 //===----------------------------------------------------------------------===//
15 #include "sanitizer_common/sanitizer_common.h"
16 #include "sanitizer_common/sanitizer_internal_defs.h"
17 #include "sanitizer_common/sanitizer_linux.h"
19 #include "dfsan/dfsan.h"
21 #include <arpa/inet.h>
36 #include <sys/resource.h>
37 #include <sys/select.h>
40 #include <sys/types.h>
44 using namespace __dfsan
;
46 #define CALL_WEAK_INTERCEPTOR_HOOK(f, ...) \
51 #define DECLARE_WEAK_INTERCEPTOR_HOOK(f, ...) \
52 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void f(__VA_ARGS__);
55 SANITIZER_INTERFACE_ATTRIBUTE
int
56 __dfsw_stat(const char *path
, struct stat
*buf
, dfsan_label path_label
,
57 dfsan_label buf_label
, dfsan_label
*ret_label
) {
58 int ret
= stat(path
, buf
);
60 dfsan_set_label(0, buf
, sizeof(struct stat
));
65 SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw_fstat(int fd
, struct stat
*buf
,
67 dfsan_label buf_label
,
68 dfsan_label
*ret_label
) {
69 int ret
= fstat(fd
, buf
);
71 dfsan_set_label(0, buf
, sizeof(struct stat
));
76 SANITIZER_INTERFACE_ATTRIBUTE
char *__dfsw_strchr(const char *s
, int c
,
79 dfsan_label
*ret_label
) {
80 for (size_t i
= 0;; ++i
) {
81 if (s
[i
] == c
|| s
[i
] == 0) {
82 if (flags().strict_data_dependencies
) {
85 *ret_label
= dfsan_union(dfsan_read_label(s
, i
+ 1),
86 dfsan_union(s_label
, c_label
));
88 return s
[i
] == 0 ? nullptr : const_cast<char *>(s
+i
);
93 DECLARE_WEAK_INTERCEPTOR_HOOK(dfsan_weak_hook_memcmp
, uptr caller_pc
,
94 const void *s1
, const void *s2
, size_t n
,
95 dfsan_label s1_label
, dfsan_label s2_label
,
98 SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw_memcmp(const void *s1
, const void *s2
,
99 size_t n
, dfsan_label s1_label
,
100 dfsan_label s2_label
,
102 dfsan_label
*ret_label
) {
103 CALL_WEAK_INTERCEPTOR_HOOK(dfsan_weak_hook_memcmp
, GET_CALLER_PC(), s1
, s2
, n
,
104 s1_label
, s2_label
, n_label
);
105 const char *cs1
= (const char *) s1
, *cs2
= (const char *) s2
;
106 for (size_t i
= 0; i
!= n
; ++i
) {
107 if (cs1
[i
] != cs2
[i
]) {
108 if (flags().strict_data_dependencies
) {
111 *ret_label
= dfsan_union(dfsan_read_label(cs1
, i
+ 1),
112 dfsan_read_label(cs2
, i
+ 1));
114 return cs1
[i
] - cs2
[i
];
118 if (flags().strict_data_dependencies
) {
121 *ret_label
= dfsan_union(dfsan_read_label(cs1
, n
),
122 dfsan_read_label(cs2
, n
));
127 DECLARE_WEAK_INTERCEPTOR_HOOK(dfsan_weak_hook_strcmp
, uptr caller_pc
,
128 const char *s1
, const char *s2
,
129 dfsan_label s1_label
, dfsan_label s2_label
)
131 SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw_strcmp(const char *s1
, const char *s2
,
132 dfsan_label s1_label
,
133 dfsan_label s2_label
,
134 dfsan_label
*ret_label
) {
135 CALL_WEAK_INTERCEPTOR_HOOK(dfsan_weak_hook_strcmp
, GET_CALLER_PC(), s1
, s2
,
137 for (size_t i
= 0;; ++i
) {
138 if (s1
[i
] != s2
[i
] || s1
[i
] == 0 || s2
[i
] == 0) {
139 if (flags().strict_data_dependencies
) {
142 *ret_label
= dfsan_union(dfsan_read_label(s1
, i
+ 1),
143 dfsan_read_label(s2
, i
+ 1));
145 return s1
[i
] - s2
[i
];
151 SANITIZER_INTERFACE_ATTRIBUTE
int
152 __dfsw_strcasecmp(const char *s1
, const char *s2
, dfsan_label s1_label
,
153 dfsan_label s2_label
, dfsan_label
*ret_label
) {
154 for (size_t i
= 0;; ++i
) {
155 if (tolower(s1
[i
]) != tolower(s2
[i
]) || s1
[i
] == 0 || s2
[i
] == 0) {
156 if (flags().strict_data_dependencies
) {
159 *ret_label
= dfsan_union(dfsan_read_label(s1
, i
+ 1),
160 dfsan_read_label(s2
, i
+ 1));
162 return s1
[i
] - s2
[i
];
168 DECLARE_WEAK_INTERCEPTOR_HOOK(dfsan_weak_hook_strncmp
, uptr caller_pc
,
169 const char *s1
, const char *s2
, size_t n
,
170 dfsan_label s1_label
, dfsan_label s2_label
,
173 SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw_strncmp(const char *s1
, const char *s2
,
174 size_t n
, dfsan_label s1_label
,
175 dfsan_label s2_label
,
177 dfsan_label
*ret_label
) {
183 CALL_WEAK_INTERCEPTOR_HOOK(dfsan_weak_hook_strncmp
, GET_CALLER_PC(), s1
, s2
,
184 n
, s1_label
, s2_label
, n_label
);
186 for (size_t i
= 0;; ++i
) {
187 if (s1
[i
] != s2
[i
] || s1
[i
] == 0 || s2
[i
] == 0 || i
== n
- 1) {
188 if (flags().strict_data_dependencies
) {
191 *ret_label
= dfsan_union(dfsan_read_label(s1
, i
+ 1),
192 dfsan_read_label(s2
, i
+ 1));
194 return s1
[i
] - s2
[i
];
200 SANITIZER_INTERFACE_ATTRIBUTE
int
201 __dfsw_strncasecmp(const char *s1
, const char *s2
, size_t n
,
202 dfsan_label s1_label
, dfsan_label s2_label
,
203 dfsan_label n_label
, dfsan_label
*ret_label
) {
209 for (size_t i
= 0;; ++i
) {
210 if (tolower(s1
[i
]) != tolower(s2
[i
]) || s1
[i
] == 0 || s2
[i
] == 0 ||
212 if (flags().strict_data_dependencies
) {
215 *ret_label
= dfsan_union(dfsan_read_label(s1
, i
+ 1),
216 dfsan_read_label(s2
, i
+ 1));
218 return s1
[i
] - s2
[i
];
224 SANITIZER_INTERFACE_ATTRIBUTE
void *__dfsw_calloc(size_t nmemb
, size_t size
,
225 dfsan_label nmemb_label
,
226 dfsan_label size_label
,
227 dfsan_label
*ret_label
) {
228 void *p
= calloc(nmemb
, size
);
229 dfsan_set_label(0, p
, nmemb
* size
);
234 SANITIZER_INTERFACE_ATTRIBUTE
size_t
235 __dfsw_strlen(const char *s
, dfsan_label s_label
, dfsan_label
*ret_label
) {
236 size_t ret
= strlen(s
);
237 if (flags().strict_data_dependencies
) {
240 *ret_label
= dfsan_read_label(s
, ret
+ 1);
246 static void *dfsan_memcpy(void *dest
, const void *src
, size_t n
) {
247 dfsan_label
*sdest
= shadow_for(dest
);
248 const dfsan_label
*ssrc
= shadow_for(src
);
249 internal_memcpy((void *)sdest
, (const void *)ssrc
, n
* sizeof(dfsan_label
));
250 return internal_memcpy(dest
, src
, n
);
253 static void dfsan_memset(void *s
, int c
, dfsan_label c_label
, size_t n
) {
254 internal_memset(s
, c
, n
);
255 dfsan_set_label(c_label
, s
, n
);
258 SANITIZER_INTERFACE_ATTRIBUTE
259 void *__dfsw_memcpy(void *dest
, const void *src
, size_t n
,
260 dfsan_label dest_label
, dfsan_label src_label
,
261 dfsan_label n_label
, dfsan_label
*ret_label
) {
262 *ret_label
= dest_label
;
263 return dfsan_memcpy(dest
, src
, n
);
266 SANITIZER_INTERFACE_ATTRIBUTE
267 void *__dfsw_memset(void *s
, int c
, size_t n
,
268 dfsan_label s_label
, dfsan_label c_label
,
269 dfsan_label n_label
, dfsan_label
*ret_label
) {
270 dfsan_memset(s
, c
, c_label
, n
);
271 *ret_label
= s_label
;
275 SANITIZER_INTERFACE_ATTRIBUTE
char *
276 __dfsw_strdup(const char *s
, dfsan_label s_label
, dfsan_label
*ret_label
) {
277 size_t len
= strlen(s
);
278 void *p
= malloc(len
+1);
279 dfsan_memcpy(p
, s
, len
+1);
281 return static_cast<char *>(p
);
284 SANITIZER_INTERFACE_ATTRIBUTE
char *
285 __dfsw_strncpy(char *s1
, const char *s2
, size_t n
, dfsan_label s1_label
,
286 dfsan_label s2_label
, dfsan_label n_label
,
287 dfsan_label
*ret_label
) {
288 size_t len
= strlen(s2
);
290 dfsan_memcpy(s1
, s2
, len
+1);
291 dfsan_memset(s1
+len
+1, 0, 0, n
-len
-1);
293 dfsan_memcpy(s1
, s2
, n
);
296 *ret_label
= s1_label
;
300 SANITIZER_INTERFACE_ATTRIBUTE ssize_t
301 __dfsw_pread(int fd
, void *buf
, size_t count
, off_t offset
,
302 dfsan_label fd_label
, dfsan_label buf_label
,
303 dfsan_label count_label
, dfsan_label offset_label
,
304 dfsan_label
*ret_label
) {
305 ssize_t ret
= pread(fd
, buf
, count
, offset
);
307 dfsan_set_label(0, buf
, ret
);
312 SANITIZER_INTERFACE_ATTRIBUTE ssize_t
313 __dfsw_read(int fd
, void *buf
, size_t count
,
314 dfsan_label fd_label
, dfsan_label buf_label
,
315 dfsan_label count_label
,
316 dfsan_label
*ret_label
) {
317 ssize_t ret
= read(fd
, buf
, count
);
319 dfsan_set_label(0, buf
, ret
);
324 SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw_clock_gettime(clockid_t clk_id
,
326 dfsan_label clk_id_label
,
327 dfsan_label tp_label
,
328 dfsan_label
*ret_label
) {
329 int ret
= clock_gettime(clk_id
, tp
);
331 dfsan_set_label(0, tp
, sizeof(struct timespec
));
336 static void unpoison(const void *ptr
, uptr size
) {
337 dfsan_set_label(0, const_cast<void *>(ptr
), size
);
340 // dlopen() ultimately calls mmap() down inside the loader, which generally
341 // doesn't participate in dynamic symbol resolution. Therefore we won't
342 // intercept its calls to mmap, and we have to hook it here.
343 SANITIZER_INTERFACE_ATTRIBUTE
void *
344 __dfsw_dlopen(const char *filename
, int flag
, dfsan_label filename_label
,
345 dfsan_label flag_label
, dfsan_label
*ret_label
) {
346 void *handle
= dlopen(filename
, flag
);
347 link_map
*map
= GET_LINK_MAP_BY_DLOPEN_HANDLE(handle
);
349 ForEachMappedRegion(map
, unpoison
);
354 struct pthread_create_info
{
355 void *(*start_routine_trampoline
)(void *, void *, dfsan_label
, dfsan_label
*);
360 static void *pthread_create_cb(void *p
) {
361 pthread_create_info
pci(*(pthread_create_info
*)p
);
363 dfsan_label ret_label
;
364 return pci
.start_routine_trampoline(pci
.start_routine
, pci
.arg
, 0,
368 SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw_pthread_create(
369 pthread_t
*thread
, const pthread_attr_t
*attr
,
370 void *(*start_routine_trampoline
)(void *, void *, dfsan_label
,
372 void *start_routine
, void *arg
, dfsan_label thread_label
,
373 dfsan_label attr_label
, dfsan_label start_routine_label
,
374 dfsan_label arg_label
, dfsan_label
*ret_label
) {
375 pthread_create_info
*pci
=
376 (pthread_create_info
*)malloc(sizeof(pthread_create_info
));
377 pci
->start_routine_trampoline
= start_routine_trampoline
;
378 pci
->start_routine
= start_routine
;
380 int rv
= pthread_create(thread
, attr
, pthread_create_cb
, (void *)pci
);
387 struct dl_iterate_phdr_info
{
388 int (*callback_trampoline
)(void *callback
, struct dl_phdr_info
*info
,
389 size_t size
, void *data
, dfsan_label info_label
,
390 dfsan_label size_label
, dfsan_label data_label
,
391 dfsan_label
*ret_label
);
396 int dl_iterate_phdr_cb(struct dl_phdr_info
*info
, size_t size
, void *data
) {
397 dl_iterate_phdr_info
*dipi
= (dl_iterate_phdr_info
*)data
;
398 dfsan_set_label(0, *info
);
399 dfsan_set_label(0, const_cast<char *>(info
->dlpi_name
),
400 strlen(info
->dlpi_name
) + 1);
402 0, const_cast<char *>(reinterpret_cast<const char *>(info
->dlpi_phdr
)),
403 sizeof(*info
->dlpi_phdr
) * info
->dlpi_phnum
);
404 dfsan_label ret_label
;
405 return dipi
->callback_trampoline(dipi
->callback
, info
, size
, dipi
->data
, 0, 0,
409 SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw_dl_iterate_phdr(
410 int (*callback_trampoline
)(void *callback
, struct dl_phdr_info
*info
,
411 size_t size
, void *data
, dfsan_label info_label
,
412 dfsan_label size_label
, dfsan_label data_label
,
413 dfsan_label
*ret_label
),
414 void *callback
, void *data
, dfsan_label callback_label
,
415 dfsan_label data_label
, dfsan_label
*ret_label
) {
416 dl_iterate_phdr_info dipi
= { callback_trampoline
, callback
, data
};
418 return dl_iterate_phdr(dl_iterate_phdr_cb
, &dipi
);
421 SANITIZER_INTERFACE_ATTRIBUTE
422 char *__dfsw_ctime_r(const time_t *timep
, char *buf
, dfsan_label timep_label
,
423 dfsan_label buf_label
, dfsan_label
*ret_label
) {
424 char *ret
= ctime_r(timep
, buf
);
426 dfsan_set_label(dfsan_read_label(timep
, sizeof(time_t)), buf
,
428 *ret_label
= buf_label
;
435 SANITIZER_INTERFACE_ATTRIBUTE
436 char *__dfsw_fgets(char *s
, int size
, FILE *stream
, dfsan_label s_label
,
437 dfsan_label size_label
, dfsan_label stream_label
,
438 dfsan_label
*ret_label
) {
439 char *ret
= fgets(s
, size
, stream
);
441 dfsan_set_label(0, ret
, strlen(ret
) + 1);
442 *ret_label
= s_label
;
449 SANITIZER_INTERFACE_ATTRIBUTE
450 char *__dfsw_getcwd(char *buf
, size_t size
, dfsan_label buf_label
,
451 dfsan_label size_label
, dfsan_label
*ret_label
) {
452 char *ret
= getcwd(buf
, size
);
454 dfsan_set_label(0, ret
, strlen(ret
) + 1);
455 *ret_label
= buf_label
;
462 SANITIZER_INTERFACE_ATTRIBUTE
463 char *__dfsw_get_current_dir_name(dfsan_label
*ret_label
) {
464 char *ret
= get_current_dir_name();
466 dfsan_set_label(0, ret
, strlen(ret
) + 1);
472 SANITIZER_INTERFACE_ATTRIBUTE
473 int __dfsw_gethostname(char *name
, size_t len
, dfsan_label name_label
,
474 dfsan_label len_label
, dfsan_label
*ret_label
) {
475 int ret
= gethostname(name
, len
);
477 dfsan_set_label(0, name
, strlen(name
) + 1);
483 SANITIZER_INTERFACE_ATTRIBUTE
484 int __dfsw_getrlimit(int resource
, struct rlimit
*rlim
,
485 dfsan_label resource_label
, dfsan_label rlim_label
,
486 dfsan_label
*ret_label
) {
487 int ret
= getrlimit(resource
, rlim
);
489 dfsan_set_label(0, rlim
, sizeof(struct rlimit
));
495 SANITIZER_INTERFACE_ATTRIBUTE
496 int __dfsw_getrusage(int who
, struct rusage
*usage
, dfsan_label who_label
,
497 dfsan_label usage_label
, dfsan_label
*ret_label
) {
498 int ret
= getrusage(who
, usage
);
500 dfsan_set_label(0, usage
, sizeof(struct rusage
));
506 SANITIZER_INTERFACE_ATTRIBUTE
507 char *__dfsw_strcpy(char *dest
, const char *src
, dfsan_label dst_label
,
508 dfsan_label src_label
, dfsan_label
*ret_label
) {
509 char *ret
= strcpy(dest
, src
);
511 internal_memcpy(shadow_for(dest
), shadow_for(src
),
512 sizeof(dfsan_label
) * (strlen(src
) + 1));
514 *ret_label
= dst_label
;
518 SANITIZER_INTERFACE_ATTRIBUTE
519 long int __dfsw_strtol(const char *nptr
, char **endptr
, int base
,
520 dfsan_label nptr_label
, dfsan_label endptr_label
,
521 dfsan_label base_label
, dfsan_label
*ret_label
) {
523 long int ret
= strtol(nptr
, &tmp_endptr
, base
);
525 *endptr
= tmp_endptr
;
527 if (tmp_endptr
> nptr
) {
528 // If *tmp_endptr is '\0' include its label as well.
529 *ret_label
= dfsan_union(
531 dfsan_read_label(nptr
, tmp_endptr
- nptr
+ (*tmp_endptr
? 0 : 1)));
538 SANITIZER_INTERFACE_ATTRIBUTE
539 double __dfsw_strtod(const char *nptr
, char **endptr
,
540 dfsan_label nptr_label
, dfsan_label endptr_label
,
541 dfsan_label
*ret_label
) {
543 double ret
= strtod(nptr
, &tmp_endptr
);
545 *endptr
= tmp_endptr
;
547 if (tmp_endptr
> nptr
) {
548 // If *tmp_endptr is '\0' include its label as well.
549 *ret_label
= dfsan_read_label(
551 tmp_endptr
- nptr
+ (*tmp_endptr
? 0 : 1));
558 SANITIZER_INTERFACE_ATTRIBUTE
559 long long int __dfsw_strtoll(const char *nptr
, char **endptr
, int base
,
560 dfsan_label nptr_label
, dfsan_label endptr_label
,
561 dfsan_label base_label
, dfsan_label
*ret_label
) {
563 long long int ret
= strtoll(nptr
, &tmp_endptr
, base
);
565 *endptr
= tmp_endptr
;
567 if (tmp_endptr
> nptr
) {
568 // If *tmp_endptr is '\0' include its label as well.
569 *ret_label
= dfsan_union(
571 dfsan_read_label(nptr
, tmp_endptr
- nptr
+ (*tmp_endptr
? 0 : 1)));
578 SANITIZER_INTERFACE_ATTRIBUTE
579 unsigned long int __dfsw_strtoul(const char *nptr
, char **endptr
, int base
,
580 dfsan_label nptr_label
, dfsan_label endptr_label
,
581 dfsan_label base_label
, dfsan_label
*ret_label
) {
583 unsigned long int ret
= strtoul(nptr
, &tmp_endptr
, base
);
585 *endptr
= tmp_endptr
;
587 if (tmp_endptr
> nptr
) {
588 // If *tmp_endptr is '\0' include its label as well.
589 *ret_label
= dfsan_union(
591 dfsan_read_label(nptr
, tmp_endptr
- nptr
+ (*tmp_endptr
? 0 : 1)));
598 SANITIZER_INTERFACE_ATTRIBUTE
599 long long unsigned int __dfsw_strtoull(const char *nptr
, char **endptr
,
600 dfsan_label nptr_label
,
601 int base
, dfsan_label endptr_label
,
602 dfsan_label base_label
,
603 dfsan_label
*ret_label
) {
605 long long unsigned int ret
= strtoull(nptr
, &tmp_endptr
, base
);
607 *endptr
= tmp_endptr
;
609 if (tmp_endptr
> nptr
) {
610 // If *tmp_endptr is '\0' include its label as well.
611 *ret_label
= dfsan_union(
613 dfsan_read_label(nptr
, tmp_endptr
- nptr
+ (*tmp_endptr
? 0 : 1)));
620 SANITIZER_INTERFACE_ATTRIBUTE
621 time_t __dfsw_time(time_t *t
, dfsan_label t_label
, dfsan_label
*ret_label
) {
622 time_t ret
= time(t
);
623 if (ret
!= (time_t) -1 && t
) {
624 dfsan_set_label(0, t
, sizeof(time_t));
630 SANITIZER_INTERFACE_ATTRIBUTE
631 int __dfsw_inet_pton(int af
, const char *src
, void *dst
, dfsan_label af_label
,
632 dfsan_label src_label
, dfsan_label dst_label
,
633 dfsan_label
*ret_label
) {
634 int ret
= inet_pton(af
, src
, dst
);
636 dfsan_set_label(dfsan_read_label(src
, strlen(src
) + 1), dst
,
637 af
== AF_INET
? sizeof(struct in_addr
) : sizeof(in6_addr
));
643 SANITIZER_INTERFACE_ATTRIBUTE
644 struct tm
*__dfsw_localtime_r(const time_t *timep
, struct tm
*result
,
645 dfsan_label timep_label
, dfsan_label result_label
,
646 dfsan_label
*ret_label
) {
647 struct tm
*ret
= localtime_r(timep
, result
);
649 dfsan_set_label(dfsan_read_label(timep
, sizeof(time_t)), result
,
651 *ret_label
= result_label
;
658 SANITIZER_INTERFACE_ATTRIBUTE
659 int __dfsw_getpwuid_r(id_t uid
, struct passwd
*pwd
,
660 char *buf
, size_t buflen
, struct passwd
**result
,
661 dfsan_label uid_label
, dfsan_label pwd_label
,
662 dfsan_label buf_label
, dfsan_label buflen_label
,
663 dfsan_label result_label
, dfsan_label
*ret_label
) {
664 // Store the data in pwd, the strings referenced from pwd in buf, and the
665 // address of pwd in *result. On failure, NULL is stored in *result.
666 int ret
= getpwuid_r(uid
, pwd
, buf
, buflen
, result
);
668 dfsan_set_label(0, pwd
, sizeof(struct passwd
));
669 dfsan_set_label(0, buf
, strlen(buf
) + 1);
672 dfsan_set_label(0, result
, sizeof(struct passwd
*));
676 SANITIZER_INTERFACE_ATTRIBUTE
677 int __dfsw_poll(struct pollfd
*fds
, nfds_t nfds
, int timeout
,
678 dfsan_label dfs_label
, dfsan_label nfds_label
,
679 dfsan_label timeout_label
, dfsan_label
*ret_label
) {
680 int ret
= poll(fds
, nfds
, timeout
);
682 for (; nfds
> 0; --nfds
) {
683 dfsan_set_label(0, &fds
[nfds
- 1].revents
, sizeof(fds
[nfds
- 1].revents
));
690 SANITIZER_INTERFACE_ATTRIBUTE
691 int __dfsw_select(int nfds
, fd_set
*readfds
, fd_set
*writefds
,
692 fd_set
*exceptfds
, struct timeval
*timeout
,
693 dfsan_label nfds_label
, dfsan_label readfds_label
,
694 dfsan_label writefds_label
, dfsan_label exceptfds_label
,
695 dfsan_label timeout_label
, dfsan_label
*ret_label
) {
696 int ret
= select(nfds
, readfds
, writefds
, exceptfds
, timeout
);
697 // Clear everything (also on error) since their content is either set or
700 dfsan_set_label(0, readfds
, sizeof(fd_set
));
703 dfsan_set_label(0, writefds
, sizeof(fd_set
));
706 dfsan_set_label(0, exceptfds
, sizeof(fd_set
));
708 dfsan_set_label(0, timeout
, sizeof(struct timeval
));
713 SANITIZER_INTERFACE_ATTRIBUTE
714 int __dfsw_sched_getaffinity(pid_t pid
, size_t cpusetsize
, cpu_set_t
*mask
,
715 dfsan_label pid_label
,
716 dfsan_label cpusetsize_label
,
717 dfsan_label mask_label
, dfsan_label
*ret_label
) {
718 int ret
= sched_getaffinity(pid
, cpusetsize
, mask
);
720 dfsan_set_label(0, mask
, cpusetsize
);
726 SANITIZER_INTERFACE_ATTRIBUTE
727 int __dfsw_sigemptyset(sigset_t
*set
, dfsan_label set_label
,
728 dfsan_label
*ret_label
) {
729 int ret
= sigemptyset(set
);
730 dfsan_set_label(0, set
, sizeof(sigset_t
));
734 SANITIZER_INTERFACE_ATTRIBUTE
735 int __dfsw_sigaction(int signum
, const struct sigaction
*act
,
736 struct sigaction
*oldact
, dfsan_label signum_label
,
737 dfsan_label act_label
, dfsan_label oldact_label
,
738 dfsan_label
*ret_label
) {
739 int ret
= sigaction(signum
, act
, oldact
);
741 dfsan_set_label(0, oldact
, sizeof(struct sigaction
));
747 SANITIZER_INTERFACE_ATTRIBUTE
748 int __dfsw_gettimeofday(struct timeval
*tv
, struct timezone
*tz
,
749 dfsan_label tv_label
, dfsan_label tz_label
,
750 dfsan_label
*ret_label
) {
751 int ret
= gettimeofday(tv
, tz
);
753 dfsan_set_label(0, tv
, sizeof(struct timeval
));
756 dfsan_set_label(0, tz
, sizeof(struct timezone
));
762 SANITIZER_INTERFACE_ATTRIBUTE
void *__dfsw_memchr(void *s
, int c
, size_t n
,
766 dfsan_label
*ret_label
) {
767 void *ret
= memchr(s
, c
, n
);
768 if (flags().strict_data_dependencies
) {
769 *ret_label
= ret
? s_label
: 0;
772 ret
? reinterpret_cast<char *>(ret
) - reinterpret_cast<char *>(s
) + 1
775 dfsan_union(dfsan_read_label(s
, len
), dfsan_union(s_label
, c_label
));
780 SANITIZER_INTERFACE_ATTRIBUTE
char *__dfsw_strrchr(char *s
, int c
,
783 dfsan_label
*ret_label
) {
784 char *ret
= strrchr(s
, c
);
785 if (flags().strict_data_dependencies
) {
786 *ret_label
= ret
? s_label
: 0;
789 dfsan_union(dfsan_read_label(s
, strlen(s
) + 1),
790 dfsan_union(s_label
, c_label
));
796 SANITIZER_INTERFACE_ATTRIBUTE
char *__dfsw_strstr(char *haystack
, char *needle
,
797 dfsan_label haystack_label
,
798 dfsan_label needle_label
,
799 dfsan_label
*ret_label
) {
800 char *ret
= strstr(haystack
, needle
);
801 if (flags().strict_data_dependencies
) {
802 *ret_label
= ret
? haystack_label
: 0;
804 size_t len
= ret
? ret
+ strlen(needle
) - haystack
: strlen(haystack
) + 1;
806 dfsan_union(dfsan_read_label(haystack
, len
),
807 dfsan_union(dfsan_read_label(needle
, strlen(needle
) + 1),
808 dfsan_union(haystack_label
, needle_label
)));
814 SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw_nanosleep(const struct timespec
*req
,
815 struct timespec
*rem
,
816 dfsan_label req_label
,
817 dfsan_label rem_label
,
818 dfsan_label
*ret_label
) {
819 int ret
= nanosleep(req
, rem
);
822 // Interrupted by a signal, rem is filled with the remaining time.
823 dfsan_set_label(0, rem
, sizeof(struct timespec
));
828 SANITIZER_INTERFACE_ATTRIBUTE
int
829 __dfsw_socketpair(int domain
, int type
, int protocol
, int sv
[2],
830 dfsan_label domain_label
, dfsan_label type_label
,
831 dfsan_label protocol_label
, dfsan_label sv_label
,
832 dfsan_label
*ret_label
) {
833 int ret
= socketpair(domain
, type
, protocol
, sv
);
836 dfsan_set_label(0, sv
, sizeof(*sv
) * 2);
841 // Type of the trampoline function passed to the custom version of
842 // dfsan_set_write_callback.
843 typedef void (*write_trampoline_t
)(
845 int fd
, const void *buf
, ssize_t count
,
846 dfsan_label fd_label
, dfsan_label buf_label
, dfsan_label count_label
);
848 // Calls to dfsan_set_write_callback() set the values in this struct.
849 // Calls to the custom version of write() read (and invoke) them.
851 write_trampoline_t write_callback_trampoline
= nullptr;
852 void *write_callback
= nullptr;
853 } write_callback_info
;
855 SANITIZER_INTERFACE_ATTRIBUTE
void
856 __dfsw_dfsan_set_write_callback(
857 write_trampoline_t write_callback_trampoline
,
858 void *write_callback
,
859 dfsan_label write_callback_label
,
860 dfsan_label
*ret_label
) {
861 write_callback_info
.write_callback_trampoline
= write_callback_trampoline
;
862 write_callback_info
.write_callback
= write_callback
;
865 SANITIZER_INTERFACE_ATTRIBUTE
int
866 __dfsw_write(int fd
, const void *buf
, size_t count
,
867 dfsan_label fd_label
, dfsan_label buf_label
,
868 dfsan_label count_label
, dfsan_label
*ret_label
) {
869 if (write_callback_info
.write_callback
) {
870 write_callback_info
.write_callback_trampoline(
871 write_callback_info
.write_callback
,
873 fd_label
, buf_label
, count_label
);
877 return write(fd
, buf
, count
);
879 } // namespace __dfsan
881 // Type used to extract a dfsan_label with va_arg()
882 typedef int dfsan_label_va
;
884 // Formats a chunk either a constant string or a single format directive (e.g.,
887 Formatter(char *str_
, const char *fmt_
, size_t size_
)
888 : str(str_
), str_off(0), size(size_
), fmt_start(fmt_
), fmt_cur(fmt_
),
892 char *tmp_fmt
= build_format_string();
894 snprintf(str
+ str_off
, str_off
< size
? size
- str_off
: 0, tmp_fmt
,
895 0 /* used only to avoid warnings */);
900 template <typename T
> int format(T arg
) {
901 char *tmp_fmt
= build_format_string();
904 retval
= snprintf(str
+ str_off
, str_off
< size
? size
- str_off
: 0,
905 tmp_fmt
, width
, arg
);
907 retval
= snprintf(str
+ str_off
, str_off
< size
? size
- str_off
: 0,
914 char *build_format_string() {
915 size_t fmt_size
= fmt_cur
- fmt_start
+ 1;
916 char *new_fmt
= (char *)malloc(fmt_size
+ 1);
918 internal_memcpy(new_fmt
, fmt_start
, fmt_size
);
919 new_fmt
[fmt_size
] = '\0';
923 char *str_cur() { return str
+ str_off
; }
925 size_t num_written_bytes(int retval
) {
930 size_t num_avail
= str_off
< size
? size
- str_off
: 0;
931 if (num_avail
== 0) {
935 size_t num_written
= retval
;
936 // A return value of {v,}snprintf of size or more means that the output was
938 if (num_written
>= num_avail
) {
939 num_written
-= num_avail
;
948 const char *fmt_start
;
953 // Formats the input and propagates the input labels to the output. The output
954 // is stored in 'str'. 'size' bounds the number of output bytes. 'format' and
955 // 'ap' are the format string and the list of arguments for formatting. Returns
956 // the return value vsnprintf would return.
958 // The function tokenizes the format string in chunks representing either a
959 // constant string or a single format directive (e.g., '%.3f') and formats each
960 // chunk independently into the output string. This approach allows to figure
961 // out which bytes of the output string depends on which argument and thus to
962 // propagate labels more precisely.
964 // WARNING: This implementation does not support conversion specifiers with
965 // positional arguments.
966 static int format_buffer(char *str
, size_t size
, const char *fmt
,
967 dfsan_label
*va_labels
, dfsan_label
*ret_label
,
969 Formatter
formatter(str
, fmt
, size
);
971 while (*formatter
.fmt_cur
) {
972 formatter
.fmt_start
= formatter
.fmt_cur
;
973 formatter
.width
= -1;
976 if (*formatter
.fmt_cur
!= '%') {
977 // Ordinary character. Consume all the characters until a '%' or the end
979 for (; *(formatter
.fmt_cur
+ 1) && *(formatter
.fmt_cur
+ 1) != '%';
980 ++formatter
.fmt_cur
) {}
981 retval
= formatter
.format();
982 dfsan_set_label(0, formatter
.str_cur(),
983 formatter
.num_written_bytes(retval
));
985 // Conversion directive. Consume all the characters until a conversion
986 // specifier or the end of the string.
987 bool end_fmt
= false;
988 for (; *formatter
.fmt_cur
&& !end_fmt
; ) {
989 switch (*++formatter
.fmt_cur
) {
996 switch (*(formatter
.fmt_cur
- 1)) {
998 // Also covers the 'hh' case (since the size of the arg is still
1000 retval
= formatter
.format(va_arg(ap
, int));
1003 if (formatter
.fmt_cur
- formatter
.fmt_start
>= 2 &&
1004 *(formatter
.fmt_cur
- 2) == 'l') {
1005 retval
= formatter
.format(va_arg(ap
, long long int));
1007 retval
= formatter
.format(va_arg(ap
, long int));
1011 retval
= formatter
.format(va_arg(ap
, long long int));
1014 retval
= formatter
.format(va_arg(ap
, intmax_t));
1018 retval
= formatter
.format(va_arg(ap
, size_t));
1021 retval
= formatter
.format(va_arg(ap
, int));
1023 dfsan_set_label(*va_labels
++, formatter
.str_cur(),
1024 formatter
.num_written_bytes(retval
));
1036 if (*(formatter
.fmt_cur
- 1) == 'L') {
1037 retval
= formatter
.format(va_arg(ap
, long double));
1039 retval
= formatter
.format(va_arg(ap
, double));
1041 dfsan_set_label(*va_labels
++, formatter
.str_cur(),
1042 formatter
.num_written_bytes(retval
));
1047 retval
= formatter
.format(va_arg(ap
, int));
1048 dfsan_set_label(*va_labels
++, formatter
.str_cur(),
1049 formatter
.num_written_bytes(retval
));
1054 char *arg
= va_arg(ap
, char *);
1055 retval
= formatter
.format(arg
);
1057 internal_memcpy(shadow_for(formatter
.str_cur()), shadow_for(arg
),
1058 sizeof(dfsan_label
) *
1059 formatter
.num_written_bytes(retval
));
1065 retval
= formatter
.format(va_arg(ap
, void *));
1066 dfsan_set_label(*va_labels
++, formatter
.str_cur(),
1067 formatter
.num_written_bytes(retval
));
1072 int *ptr
= va_arg(ap
, int *);
1073 *ptr
= (int)formatter
.str_off
;
1075 dfsan_set_label(0, ptr
, sizeof(ptr
));
1081 retval
= formatter
.format();
1082 dfsan_set_label(0, formatter
.str_cur(),
1083 formatter
.num_written_bytes(retval
));
1088 formatter
.width
= va_arg(ap
, int);
1102 formatter
.fmt_cur
++;
1103 formatter
.str_off
+= retval
;
1108 // Number of bytes written in total.
1109 return formatter
.str_off
;
1113 SANITIZER_INTERFACE_ATTRIBUTE
1114 int __dfsw_sprintf(char *str
, const char *format
, dfsan_label str_label
,
1115 dfsan_label format_label
, dfsan_label
*va_labels
,
1116 dfsan_label
*ret_label
, ...) {
1118 va_start(ap
, ret_label
);
1119 int ret
= format_buffer(str
, ~0ul, format
, va_labels
, ret_label
, ap
);
1124 SANITIZER_INTERFACE_ATTRIBUTE
1125 int __dfsw_snprintf(char *str
, size_t size
, const char *format
,
1126 dfsan_label str_label
, dfsan_label size_label
,
1127 dfsan_label format_label
, dfsan_label
*va_labels
,
1128 dfsan_label
*ret_label
, ...) {
1130 va_start(ap
, ret_label
);
1131 int ret
= format_buffer(str
, size
, format
, va_labels
, ret_label
, ap
);