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;
47 SANITIZER_INTERFACE_ATTRIBUTE int
48 __dfsw_stat(const char *path, struct stat *buf, dfsan_label path_label,
49 dfsan_label buf_label, dfsan_label *ret_label) {
50 int ret = stat(path, buf);
52 dfsan_set_label(0, buf, sizeof(struct stat));
57 SANITIZER_INTERFACE_ATTRIBUTE int __dfsw_fstat(int fd, struct stat *buf,
59 dfsan_label buf_label,
60 dfsan_label *ret_label) {
61 int ret = fstat(fd, buf);
63 dfsan_set_label(0, buf, sizeof(struct stat));
68 SANITIZER_INTERFACE_ATTRIBUTE char *__dfsw_strchr(const char *s, int c,
71 dfsan_label *ret_label) {
72 for (size_t i = 0;; ++i) {
73 if (s[i] == c || s[i] == 0) {
74 if (flags().strict_data_dependencies) {
77 *ret_label = dfsan_union(dfsan_read_label(s, i + 1),
78 dfsan_union(s_label, c_label));
80 return s[i] == 0 ? 0 : const_cast<char *>(s+i);
85 SANITIZER_INTERFACE_ATTRIBUTE int __dfsw_memcmp(const void *s1, const void *s2,
86 size_t n, dfsan_label s1_label,
89 dfsan_label *ret_label) {
90 const char *cs1 = (const char *) s1, *cs2 = (const char *) s2;
91 for (size_t i = 0; i != n; ++i) {
92 if (cs1[i] != cs2[i]) {
93 if (flags().strict_data_dependencies) {
96 *ret_label = dfsan_union(dfsan_read_label(cs1, i + 1),
97 dfsan_read_label(cs2, i + 1));
99 return cs1[i] - cs2[i];
103 if (flags().strict_data_dependencies) {
106 *ret_label = dfsan_union(dfsan_read_label(cs1, n),
107 dfsan_read_label(cs2, n));
112 SANITIZER_INTERFACE_ATTRIBUTE int __dfsw_strcmp(const char *s1, const char *s2,
113 dfsan_label s1_label,
114 dfsan_label s2_label,
115 dfsan_label *ret_label) {
116 for (size_t i = 0;; ++i) {
117 if (s1[i] != s2[i] || s1[i] == 0 || s2[i] == 0) {
118 if (flags().strict_data_dependencies) {
121 *ret_label = dfsan_union(dfsan_read_label(s1, i + 1),
122 dfsan_read_label(s2, i + 1));
124 return s1[i] - s2[i];
130 SANITIZER_INTERFACE_ATTRIBUTE int
131 __dfsw_strcasecmp(const char *s1, const char *s2, dfsan_label s1_label,
132 dfsan_label s2_label, dfsan_label *ret_label) {
133 for (size_t i = 0;; ++i) {
134 if (tolower(s1[i]) != tolower(s2[i]) || s1[i] == 0 || s2[i] == 0) {
135 if (flags().strict_data_dependencies) {
138 *ret_label = dfsan_union(dfsan_read_label(s1, i + 1),
139 dfsan_read_label(s2, i + 1));
141 return s1[i] - s2[i];
147 SANITIZER_INTERFACE_ATTRIBUTE int __dfsw_strncmp(const char *s1, const char *s2,
148 size_t n, dfsan_label s1_label,
149 dfsan_label s2_label,
151 dfsan_label *ret_label) {
157 for (size_t i = 0;; ++i) {
158 if (s1[i] != s2[i] || s1[i] == 0 || s2[i] == 0 || i == n - 1) {
159 if (flags().strict_data_dependencies) {
162 *ret_label = dfsan_union(dfsan_read_label(s1, i + 1),
163 dfsan_read_label(s2, i + 1));
165 return s1[i] - s2[i];
171 SANITIZER_INTERFACE_ATTRIBUTE int
172 __dfsw_strncasecmp(const char *s1, const char *s2, size_t n,
173 dfsan_label s1_label, dfsan_label s2_label,
174 dfsan_label n_label, dfsan_label *ret_label) {
180 for (size_t i = 0;; ++i) {
181 if (tolower(s1[i]) != tolower(s2[i]) || s1[i] == 0 || s2[i] == 0 ||
183 if (flags().strict_data_dependencies) {
186 *ret_label = dfsan_union(dfsan_read_label(s1, i + 1),
187 dfsan_read_label(s2, i + 1));
189 return s1[i] - s2[i];
195 SANITIZER_INTERFACE_ATTRIBUTE void *__dfsw_calloc(size_t nmemb, size_t size,
196 dfsan_label nmemb_label,
197 dfsan_label size_label,
198 dfsan_label *ret_label) {
199 void *p = calloc(nmemb, size);
200 dfsan_set_label(0, p, nmemb * size);
205 SANITIZER_INTERFACE_ATTRIBUTE size_t
206 __dfsw_strlen(const char *s, dfsan_label s_label, dfsan_label *ret_label) {
207 size_t ret = strlen(s);
208 if (flags().strict_data_dependencies) {
211 *ret_label = dfsan_read_label(s, ret + 1);
217 static void *dfsan_memcpy(void *dest, const void *src, size_t n) {
218 dfsan_label *sdest = shadow_for(dest);
219 const dfsan_label *ssrc = shadow_for(src);
220 internal_memcpy((void *)sdest, (const void *)ssrc, n * sizeof(dfsan_label));
221 return internal_memcpy(dest, src, n);
224 static void dfsan_memset(void *s, int c, dfsan_label c_label, size_t n) {
225 internal_memset(s, c, n);
226 dfsan_set_label(c_label, s, n);
229 SANITIZER_INTERFACE_ATTRIBUTE
230 void *__dfsw_memcpy(void *dest, const void *src, size_t n,
231 dfsan_label dest_label, dfsan_label src_label,
232 dfsan_label n_label, dfsan_label *ret_label) {
233 *ret_label = dest_label;
234 return dfsan_memcpy(dest, src, n);
237 SANITIZER_INTERFACE_ATTRIBUTE
238 void *__dfsw_memset(void *s, int c, size_t n,
239 dfsan_label s_label, dfsan_label c_label,
240 dfsan_label n_label, dfsan_label *ret_label) {
241 dfsan_memset(s, c, c_label, n);
242 *ret_label = s_label;
246 SANITIZER_INTERFACE_ATTRIBUTE char *
247 __dfsw_strdup(const char *s, dfsan_label s_label, dfsan_label *ret_label) {
248 size_t len = strlen(s);
249 void *p = malloc(len+1);
250 dfsan_memcpy(p, s, len+1);
252 return static_cast<char *>(p);
255 SANITIZER_INTERFACE_ATTRIBUTE char *
256 __dfsw_strncpy(char *s1, const char *s2, size_t n, dfsan_label s1_label,
257 dfsan_label s2_label, dfsan_label n_label,
258 dfsan_label *ret_label) {
259 size_t len = strlen(s2);
261 dfsan_memcpy(s1, s2, len+1);
262 dfsan_memset(s1+len+1, 0, 0, n-len-1);
264 dfsan_memcpy(s1, s2, n);
267 *ret_label = s1_label;
271 SANITIZER_INTERFACE_ATTRIBUTE ssize_t
272 __dfsw_pread(int fd, void *buf, size_t count, off_t offset,
273 dfsan_label fd_label, dfsan_label buf_label,
274 dfsan_label count_label, dfsan_label offset_label,
275 dfsan_label *ret_label) {
276 ssize_t ret = pread(fd, buf, count, offset);
278 dfsan_set_label(0, buf, ret);
283 SANITIZER_INTERFACE_ATTRIBUTE ssize_t
284 __dfsw_read(int fd, void *buf, size_t count,
285 dfsan_label fd_label, dfsan_label buf_label,
286 dfsan_label count_label,
287 dfsan_label *ret_label) {
288 ssize_t ret = read(fd, buf, count);
290 dfsan_set_label(0, buf, ret);
295 SANITIZER_INTERFACE_ATTRIBUTE int __dfsw_clock_gettime(clockid_t clk_id,
297 dfsan_label clk_id_label,
298 dfsan_label tp_label,
299 dfsan_label *ret_label) {
300 int ret = clock_gettime(clk_id, tp);
302 dfsan_set_label(0, tp, sizeof(struct timespec));
307 static void unpoison(const void *ptr, uptr size) {
308 dfsan_set_label(0, const_cast<void *>(ptr), size);
311 // dlopen() ultimately calls mmap() down inside the loader, which generally
312 // doesn't participate in dynamic symbol resolution. Therefore we won't
313 // intercept its calls to mmap, and we have to hook it here.
314 SANITIZER_INTERFACE_ATTRIBUTE void *
315 __dfsw_dlopen(const char *filename, int flag, dfsan_label filename_label,
316 dfsan_label flag_label, dfsan_label *ret_label) {
317 link_map *map = (link_map *)dlopen(filename, flag);
319 ForEachMappedRegion(map, unpoison);
324 struct pthread_create_info {
325 void *(*start_routine_trampoline)(void *, void *, dfsan_label, dfsan_label *);
330 static void *pthread_create_cb(void *p) {
331 pthread_create_info pci(*(pthread_create_info *)p);
333 dfsan_label ret_label;
334 return pci.start_routine_trampoline(pci.start_routine, pci.arg, 0,
338 SANITIZER_INTERFACE_ATTRIBUTE int __dfsw_pthread_create(
339 pthread_t *thread, const pthread_attr_t *attr,
340 void *(*start_routine_trampoline)(void *, void *, dfsan_label,
342 void *start_routine, void *arg, dfsan_label thread_label,
343 dfsan_label attr_label, dfsan_label start_routine_label,
344 dfsan_label arg_label, dfsan_label *ret_label) {
345 pthread_create_info *pci =
346 (pthread_create_info *)malloc(sizeof(pthread_create_info));
347 pci->start_routine_trampoline = start_routine_trampoline;
348 pci->start_routine = start_routine;
350 int rv = pthread_create(thread, attr, pthread_create_cb, (void *)pci);
357 struct dl_iterate_phdr_info {
358 int (*callback_trampoline)(void *callback, struct dl_phdr_info *info,
359 size_t size, void *data, dfsan_label info_label,
360 dfsan_label size_label, dfsan_label data_label,
361 dfsan_label *ret_label);
366 int dl_iterate_phdr_cb(struct dl_phdr_info *info, size_t size, void *data) {
367 dl_iterate_phdr_info *dipi = (dl_iterate_phdr_info *)data;
368 dfsan_set_label(0, *info);
369 dfsan_set_label(0, const_cast<char *>(info->dlpi_name),
370 strlen(info->dlpi_name) + 1);
372 0, const_cast<char *>(reinterpret_cast<const char *>(info->dlpi_phdr)),
373 sizeof(*info->dlpi_phdr) * info->dlpi_phnum);
374 dfsan_label ret_label;
375 return dipi->callback_trampoline(dipi->callback, info, size, dipi->data, 0, 0,
379 SANITIZER_INTERFACE_ATTRIBUTE int __dfsw_dl_iterate_phdr(
380 int (*callback_trampoline)(void *callback, struct dl_phdr_info *info,
381 size_t size, void *data, dfsan_label info_label,
382 dfsan_label size_label, dfsan_label data_label,
383 dfsan_label *ret_label),
384 void *callback, void *data, dfsan_label callback_label,
385 dfsan_label data_label, dfsan_label *ret_label) {
386 dl_iterate_phdr_info dipi = { callback_trampoline, callback, data };
388 return dl_iterate_phdr(dl_iterate_phdr_cb, &dipi);
391 SANITIZER_INTERFACE_ATTRIBUTE
392 char *__dfsw_ctime_r(const time_t *timep, char *buf, dfsan_label timep_label,
393 dfsan_label buf_label, dfsan_label *ret_label) {
394 char *ret = ctime_r(timep, buf);
396 dfsan_set_label(dfsan_read_label(timep, sizeof(time_t)), buf,
398 *ret_label = buf_label;
405 SANITIZER_INTERFACE_ATTRIBUTE
406 char *__dfsw_fgets(char *s, int size, FILE *stream, dfsan_label s_label,
407 dfsan_label size_label, dfsan_label stream_label,
408 dfsan_label *ret_label) {
409 char *ret = fgets(s, size, stream);
411 dfsan_set_label(0, ret, strlen(ret) + 1);
412 *ret_label = s_label;
419 SANITIZER_INTERFACE_ATTRIBUTE
420 char *__dfsw_getcwd(char *buf, size_t size, dfsan_label buf_label,
421 dfsan_label size_label, dfsan_label *ret_label) {
422 char *ret = getcwd(buf, size);
424 dfsan_set_label(0, ret, strlen(ret) + 1);
425 *ret_label = buf_label;
432 SANITIZER_INTERFACE_ATTRIBUTE
433 char *__dfsw_get_current_dir_name(dfsan_label *ret_label) {
434 char *ret = get_current_dir_name();
436 dfsan_set_label(0, ret, strlen(ret) + 1);
442 SANITIZER_INTERFACE_ATTRIBUTE
443 int __dfsw_gethostname(char *name, size_t len, dfsan_label name_label,
444 dfsan_label len_label, dfsan_label *ret_label) {
445 int ret = gethostname(name, len);
447 dfsan_set_label(0, name, strlen(name) + 1);
453 SANITIZER_INTERFACE_ATTRIBUTE
454 int __dfsw_getrlimit(int resource, struct rlimit *rlim,
455 dfsan_label resource_label, dfsan_label rlim_label,
456 dfsan_label *ret_label) {
457 int ret = getrlimit(resource, rlim);
459 dfsan_set_label(0, rlim, sizeof(struct rlimit));
465 SANITIZER_INTERFACE_ATTRIBUTE
466 int __dfsw_getrusage(int who, struct rusage *usage, dfsan_label who_label,
467 dfsan_label usage_label, dfsan_label *ret_label) {
468 int ret = getrusage(who, usage);
470 dfsan_set_label(0, usage, sizeof(struct rusage));
476 SANITIZER_INTERFACE_ATTRIBUTE
477 char *__dfsw_strcpy(char *dest, const char *src, dfsan_label dst_label,
478 dfsan_label src_label, dfsan_label *ret_label) {
479 char *ret = strcpy(dest, src);
481 internal_memcpy(shadow_for(dest), shadow_for(src),
482 sizeof(dfsan_label) * (strlen(src) + 1));
484 *ret_label = dst_label;
488 SANITIZER_INTERFACE_ATTRIBUTE
489 long int __dfsw_strtol(const char *nptr, char **endptr, int base,
490 dfsan_label nptr_label, dfsan_label endptr_label,
491 dfsan_label base_label, dfsan_label *ret_label) {
493 long int ret = strtol(nptr, &tmp_endptr, base);
495 *endptr = tmp_endptr;
497 if (tmp_endptr > nptr) {
498 // If *tmp_endptr is '\0' include its label as well.
499 *ret_label = dfsan_union(
501 dfsan_read_label(nptr, tmp_endptr - nptr + (*tmp_endptr ? 0 : 1)));
508 SANITIZER_INTERFACE_ATTRIBUTE
509 double __dfsw_strtod(const char *nptr, char **endptr,
510 dfsan_label nptr_label, dfsan_label endptr_label,
511 dfsan_label *ret_label) {
513 double ret = strtod(nptr, &tmp_endptr);
515 *endptr = tmp_endptr;
517 if (tmp_endptr > nptr) {
518 // If *tmp_endptr is '\0' include its label as well.
519 *ret_label = dfsan_read_label(
521 tmp_endptr - nptr + (*tmp_endptr ? 0 : 1));
528 SANITIZER_INTERFACE_ATTRIBUTE
529 long long int __dfsw_strtoll(const char *nptr, char **endptr, int base,
530 dfsan_label nptr_label, dfsan_label endptr_label,
531 dfsan_label base_label, dfsan_label *ret_label) {
533 long long int ret = strtoll(nptr, &tmp_endptr, base);
535 *endptr = tmp_endptr;
537 if (tmp_endptr > nptr) {
538 // If *tmp_endptr is '\0' include its label as well.
539 *ret_label = dfsan_union(
541 dfsan_read_label(nptr, tmp_endptr - nptr + (*tmp_endptr ? 0 : 1)));
548 SANITIZER_INTERFACE_ATTRIBUTE
549 unsigned long int __dfsw_strtoul(const char *nptr, char **endptr, int base,
550 dfsan_label nptr_label, dfsan_label endptr_label,
551 dfsan_label base_label, dfsan_label *ret_label) {
553 unsigned long int ret = strtoul(nptr, &tmp_endptr, base);
555 *endptr = tmp_endptr;
557 if (tmp_endptr > nptr) {
558 // If *tmp_endptr is '\0' include its label as well.
559 *ret_label = dfsan_union(
561 dfsan_read_label(nptr, tmp_endptr - nptr + (*tmp_endptr ? 0 : 1)));
568 SANITIZER_INTERFACE_ATTRIBUTE
569 long long unsigned int __dfsw_strtoull(const char *nptr, char **endptr,
570 dfsan_label nptr_label,
571 int base, dfsan_label endptr_label,
572 dfsan_label base_label,
573 dfsan_label *ret_label) {
575 long long unsigned int ret = strtoull(nptr, &tmp_endptr, base);
577 *endptr = tmp_endptr;
579 if (tmp_endptr > nptr) {
580 // If *tmp_endptr is '\0' include its label as well.
581 *ret_label = dfsan_union(
583 dfsan_read_label(nptr, tmp_endptr - nptr + (*tmp_endptr ? 0 : 1)));
590 SANITIZER_INTERFACE_ATTRIBUTE
591 time_t __dfsw_time(time_t *t, dfsan_label t_label, dfsan_label *ret_label) {
592 time_t ret = time(t);
593 if (ret != (time_t) -1 && t) {
594 dfsan_set_label(0, t, sizeof(time_t));
600 SANITIZER_INTERFACE_ATTRIBUTE
601 int __dfsw_inet_pton(int af, const char *src, void *dst, dfsan_label af_label,
602 dfsan_label src_label, dfsan_label dst_label,
603 dfsan_label *ret_label) {
604 int ret = inet_pton(af, src, dst);
606 dfsan_set_label(dfsan_read_label(src, strlen(src) + 1), dst,
607 af == AF_INET ? sizeof(struct in_addr) : sizeof(in6_addr));
613 SANITIZER_INTERFACE_ATTRIBUTE
614 struct tm *__dfsw_localtime_r(const time_t *timep, struct tm *result,
615 dfsan_label timep_label, dfsan_label result_label,
616 dfsan_label *ret_label) {
617 struct tm *ret = localtime_r(timep, result);
619 dfsan_set_label(dfsan_read_label(timep, sizeof(time_t)), result,
621 *ret_label = result_label;
628 SANITIZER_INTERFACE_ATTRIBUTE
629 int __dfsw_getpwuid_r(id_t uid, struct passwd *pwd,
630 char *buf, size_t buflen, struct passwd **result,
631 dfsan_label uid_label, dfsan_label pwd_label,
632 dfsan_label buf_label, dfsan_label buflen_label,
633 dfsan_label result_label, dfsan_label *ret_label) {
634 // Store the data in pwd, the strings referenced from pwd in buf, and the
635 // address of pwd in *result. On failure, NULL is stored in *result.
636 int ret = getpwuid_r(uid, pwd, buf, buflen, result);
638 dfsan_set_label(0, pwd, sizeof(struct passwd));
639 dfsan_set_label(0, buf, strlen(buf) + 1);
642 dfsan_set_label(0, result, sizeof(struct passwd*));
646 SANITIZER_INTERFACE_ATTRIBUTE
647 int __dfsw_poll(struct pollfd *fds, nfds_t nfds, int timeout,
648 dfsan_label dfs_label, dfsan_label nfds_label,
649 dfsan_label timeout_label, dfsan_label *ret_label) {
650 int ret = poll(fds, nfds, timeout);
652 for (; nfds > 0; --nfds) {
653 dfsan_set_label(0, &fds[nfds - 1].revents, sizeof(fds[nfds - 1].revents));
660 SANITIZER_INTERFACE_ATTRIBUTE
661 int __dfsw_select(int nfds, fd_set *readfds, fd_set *writefds,
662 fd_set *exceptfds, struct timeval *timeout,
663 dfsan_label nfds_label, dfsan_label readfds_label,
664 dfsan_label writefds_label, dfsan_label exceptfds_label,
665 dfsan_label timeout_label, dfsan_label *ret_label) {
666 int ret = select(nfds, readfds, writefds, exceptfds, timeout);
667 // Clear everything (also on error) since their content is either set or
670 dfsan_set_label(0, readfds, sizeof(fd_set));
673 dfsan_set_label(0, writefds, sizeof(fd_set));
676 dfsan_set_label(0, exceptfds, sizeof(fd_set));
678 dfsan_set_label(0, timeout, sizeof(struct timeval));
683 SANITIZER_INTERFACE_ATTRIBUTE
684 int __dfsw_sched_getaffinity(pid_t pid, size_t cpusetsize, cpu_set_t *mask,
685 dfsan_label pid_label,
686 dfsan_label cpusetsize_label,
687 dfsan_label mask_label, dfsan_label *ret_label) {
688 int ret = sched_getaffinity(pid, cpusetsize, mask);
690 dfsan_set_label(0, mask, cpusetsize);
696 SANITIZER_INTERFACE_ATTRIBUTE
697 int __dfsw_sigemptyset(sigset_t *set, dfsan_label set_label,
698 dfsan_label *ret_label) {
699 int ret = sigemptyset(set);
700 dfsan_set_label(0, set, sizeof(sigset_t));
704 SANITIZER_INTERFACE_ATTRIBUTE
705 int __dfsw_sigaction(int signum, const struct sigaction *act,
706 struct sigaction *oldact, dfsan_label signum_label,
707 dfsan_label act_label, dfsan_label oldact_label,
708 dfsan_label *ret_label) {
709 int ret = sigaction(signum, act, oldact);
711 dfsan_set_label(0, oldact, sizeof(struct sigaction));
717 SANITIZER_INTERFACE_ATTRIBUTE
718 int __dfsw_gettimeofday(struct timeval *tv, struct timezone *tz,
719 dfsan_label tv_label, dfsan_label tz_label,
720 dfsan_label *ret_label) {
721 int ret = gettimeofday(tv, tz);
723 dfsan_set_label(0, tv, sizeof(struct timeval));
726 dfsan_set_label(0, tz, sizeof(struct timezone));
732 SANITIZER_INTERFACE_ATTRIBUTE void *__dfsw_memchr(void *s, int c, size_t n,
736 dfsan_label *ret_label) {
737 void *ret = memchr(s, c, n);
738 if (flags().strict_data_dependencies) {
739 *ret_label = ret ? s_label : 0;
742 ret ? reinterpret_cast<char *>(ret) - reinterpret_cast<char *>(s) + 1
745 dfsan_union(dfsan_read_label(s, len), dfsan_union(s_label, c_label));
750 SANITIZER_INTERFACE_ATTRIBUTE char *__dfsw_strrchr(char *s, int c,
753 dfsan_label *ret_label) {
754 char *ret = strrchr(s, c);
755 if (flags().strict_data_dependencies) {
756 *ret_label = ret ? s_label : 0;
759 dfsan_union(dfsan_read_label(s, strlen(s) + 1),
760 dfsan_union(s_label, c_label));
766 SANITIZER_INTERFACE_ATTRIBUTE char *__dfsw_strstr(char *haystack, char *needle,
767 dfsan_label haystack_label,
768 dfsan_label needle_label,
769 dfsan_label *ret_label) {
770 char *ret = strstr(haystack, needle);
771 if (flags().strict_data_dependencies) {
772 *ret_label = ret ? haystack_label : 0;
774 size_t len = ret ? ret + strlen(needle) - haystack : strlen(haystack) + 1;
776 dfsan_union(dfsan_read_label(haystack, len),
777 dfsan_union(dfsan_read_label(needle, strlen(needle) + 1),
778 dfsan_union(haystack_label, needle_label)));
784 SANITIZER_INTERFACE_ATTRIBUTE int __dfsw_nanosleep(const struct timespec *req,
785 struct timespec *rem,
786 dfsan_label req_label,
787 dfsan_label rem_label,
788 dfsan_label *ret_label) {
789 int ret = nanosleep(req, rem);
792 // Interrupted by a signal, rem is filled with the remaining time.
793 dfsan_set_label(0, rem, sizeof(struct timespec));
798 SANITIZER_INTERFACE_ATTRIBUTE int
799 __dfsw_socketpair(int domain, int type, int protocol, int sv[2],
800 dfsan_label domain_label, dfsan_label type_label,
801 dfsan_label protocol_label, dfsan_label sv_label,
802 dfsan_label *ret_label) {
803 int ret = socketpair(domain, type, protocol, sv);
806 dfsan_set_label(0, sv, sizeof(*sv) * 2);
811 // Type of the trampoline function passed to the custom version of
812 // dfsan_set_write_callback.
813 typedef void (*write_trampoline_t)(
815 int fd, const void *buf, ssize_t count,
816 dfsan_label fd_label, dfsan_label buf_label, dfsan_label count_label);
818 // Calls to dfsan_set_write_callback() set the values in this struct.
819 // Calls to the custom version of write() read (and invoke) them.
821 write_trampoline_t write_callback_trampoline = NULL;
822 void *write_callback = NULL;
823 } write_callback_info;
825 SANITIZER_INTERFACE_ATTRIBUTE void
826 __dfsw_dfsan_set_write_callback(
827 write_trampoline_t write_callback_trampoline,
828 void *write_callback,
829 dfsan_label write_callback_label,
830 dfsan_label *ret_label) {
831 write_callback_info.write_callback_trampoline = write_callback_trampoline;
832 write_callback_info.write_callback = write_callback;
835 SANITIZER_INTERFACE_ATTRIBUTE int
836 __dfsw_write(int fd, const void *buf, size_t count,
837 dfsan_label fd_label, dfsan_label buf_label,
838 dfsan_label count_label, dfsan_label *ret_label) {
839 if (write_callback_info.write_callback != NULL) {
840 write_callback_info.write_callback_trampoline(
841 write_callback_info.write_callback,
843 fd_label, buf_label, count_label);
847 return write(fd, buf, count);
850 // Type used to extract a dfsan_label with va_arg()
851 typedef int dfsan_label_va;
853 // A chunk of data representing the output of formatting either a constant
854 // string or a single format directive.
856 // Address of the beginning of the formatted string
858 // Size of the formatted string
861 // Type of DFSan label (depends on the format directive)
863 // Constant string, no argument and thus no label
865 // Label for an argument of '%n'
867 // Label for a '%s' argument
869 // Label for any other type of argument
873 // Value of the argument (if label_type == STRING)
877 // Formats the input. The output is stored in 'str' starting from offset
878 // 'off'. The format directive is represented by the first 'format_size' bytes
879 // of 'format'. If 'has_size' is true, 'size' bounds the number of output
880 // bytes. Returns the return value of the vsnprintf call used to format the
882 static int format_chunk(char *str, size_t off, bool has_size, size_t size,
883 const char *format, size_t format_size, ...) {
884 char *chunk_format = (char *) malloc(format_size + 1);
885 assert(chunk_format);
886 internal_memcpy(chunk_format, format, format_size);
887 chunk_format[format_size] = '\0';
890 va_start(ap, format_size);
893 r = vsnprintf(str + off, off < size ? size - off : 0, chunk_format, ap);
895 r = vsprintf(str + off, chunk_format, ap);
903 // Formats the input and propagates the input labels to the output. The output
904 // is stored in 'str'. If 'has_size' is true, 'size' bounds the number of
905 // output bytes. 'format' and 'ap' are the format string and the list of
906 // arguments for formatting. Returns the return value vsnprintf would return.
908 // The function tokenizes the format string in chunks representing either a
909 // constant string or a single format directive (e.g., '%.3f') and formats each
910 // chunk independently into the output string. This approach allows to figure
911 // out which bytes of the output string depends on which argument and thus to
912 // propagate labels more precisely.
913 static int format_buffer(char *str, bool has_size, size_t size,
914 const char *format, dfsan_label *va_labels,
915 dfsan_label *ret_label, va_list ap) {
916 InternalMmapVector<Chunk> chunks(8);
920 chunks.push_back(Chunk());
921 Chunk& chunk = chunks.back();
922 chunk.ptr = str + off;
927 if (*format != '%') {
928 // Ordinary character. Consume all the characters until a '%' or the end
930 size_t format_size = 0;
931 for (; *format && *format != '%'; ++format, ++format_size) {}
932 status = format_chunk(str, off, has_size, size, format - format_size,
934 chunk.label_type = Chunk::NONE;
936 // Conversion directive. Consume all the characters until a conversion
937 // specifier or the end of the string.
938 bool end_format = false;
939 #define FORMAT_CHUNK(t) \
940 format_chunk(str, off, has_size, size, format - format_size, \
941 format_size + 1, va_arg(ap, t))
943 for (size_t format_size = 1; *++format && !end_format; ++format_size) {
951 switch (*(format - 1)) {
953 // Also covers the 'hh' case (since the size of the arg is still
955 status = FORMAT_CHUNK(int);
958 if (format_size >= 2 && *(format - 2) == 'l') {
959 status = FORMAT_CHUNK(long long int);
961 status = FORMAT_CHUNK(long int);
965 status = FORMAT_CHUNK(long long int);
968 status = FORMAT_CHUNK(intmax_t);
971 status = FORMAT_CHUNK(size_t);
974 status = FORMAT_CHUNK(size_t);
977 status = FORMAT_CHUNK(int);
979 chunk.label_type = Chunk::NUMERIC;
991 if (*(format - 1) == 'L') {
992 status = FORMAT_CHUNK(long double);
994 status = FORMAT_CHUNK(double);
996 chunk.label_type = Chunk::NUMERIC;
1001 status = FORMAT_CHUNK(int);
1002 chunk.label_type = Chunk::NUMERIC;
1007 chunk.arg = va_arg(ap, char *);
1009 format_chunk(str, off, has_size, size,
1010 format - format_size, format_size + 1,
1012 chunk.label_type = Chunk::STRING;
1017 status = FORMAT_CHUNK(void *);
1018 chunk.label_type = Chunk::NUMERIC;
1023 *(va_arg(ap, int *)) = (int)off;
1024 chunk.label_type = Chunk::IGNORED;
1029 status = format_chunk(str, off, has_size, size,
1030 format - format_size, format_size + 1);
1031 chunk.label_type = Chunk::NONE;
1046 // A return value of {v,}snprintf of size or more means that the output was
1050 size_t ustatus = (size_t) status;
1051 chunk.size = ustatus >= (size - off) ?
1052 ustatus - (size - off) : ustatus;
1057 chunk.size = status;
1062 // TODO(martignlo): Decide how to combine labels (e.g., whether to ignore or
1063 // not the label of the format string).
1065 // Label each output chunk according to the label supplied as argument to the
1066 // function. We need to go through all the chunks and arguments even if the
1067 // string was only partially printed ({v,}snprintf case).
1068 for (size_t i = 0; i < chunks.size(); ++i) {
1069 const Chunk& chunk = chunks[i];
1070 void *chunk_ptr = const_cast<char *>(chunk.ptr);
1072 switch (chunk.label_type) {
1074 dfsan_set_label(0, chunk_ptr, chunk.size);
1076 case Chunk::IGNORED:
1078 dfsan_set_label(0, chunk_ptr, chunk.size);
1080 case Chunk::NUMERIC: {
1081 dfsan_label label = *va_labels++;
1082 dfsan_set_label(label, chunk_ptr, chunk.size);
1085 case Chunk::STRING: {
1086 // Consume the label of the pointer to the string
1088 internal_memcpy(shadow_for(chunk_ptr),
1089 shadow_for(chunk.arg),
1090 sizeof(dfsan_label) * (strlen(chunk.arg)));
1098 // Number of bytes written in total.
1102 SANITIZER_INTERFACE_ATTRIBUTE
1103 int __dfsw_sprintf(char *str, const char *format, dfsan_label str_label,
1104 dfsan_label format_label, dfsan_label *va_labels,
1105 dfsan_label *ret_label, ...) {
1107 va_start(ap, ret_label);
1108 int ret = format_buffer(str, false, 0, format, va_labels, ret_label, ap);
1113 SANITIZER_INTERFACE_ATTRIBUTE
1114 int __dfsw_snprintf(char *str, size_t size, const char *format,
1115 dfsan_label str_label, dfsan_label size_label,
1116 dfsan_label format_label, dfsan_label *va_labels,
1117 dfsan_label *ret_label, ...) {
1119 va_start(ap, ret_label);
1120 int ret = format_buffer(str, true, size, format, va_labels, ret_label, ap);