master
1//===-- sanitizer_linux_libcdep.cpp ---------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file is shared between AddressSanitizer and ThreadSanitizer
10// run-time libraries and implements linux-specific functions from
11// sanitizer_libc.h.
12//===----------------------------------------------------------------------===//
13
14#include "sanitizer_platform.h"
15
16#if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \
17 SANITIZER_SOLARIS || SANITIZER_HAIKU
18
19# include "sanitizer_allocator_internal.h"
20# include "sanitizer_atomic.h"
21# include "sanitizer_common.h"
22# include "sanitizer_file.h"
23# include "sanitizer_flags.h"
24# include "sanitizer_getauxval.h"
25# include "sanitizer_glibc_version.h"
26# include "sanitizer_linux.h"
27# include "sanitizer_placement_new.h"
28# include "sanitizer_procmaps.h"
29# include "sanitizer_solaris.h"
30
31# if SANITIZER_HAIKU
32# define _DEFAULT_SOURCE
33# endif
34
35# if SANITIZER_NETBSD
36# // for __lwp_gettcb_fast() / __lwp_getprivate_fast()
37# define _RTLD_SOURCE
38# include <machine/mcontext.h>
39# undef _RTLD_SOURCE
40# include <sys/param.h>
41# if __NetBSD_Version__ >= 1099001200
42# include <machine/lwp_private.h>
43# endif
44# endif
45
46# include <dlfcn.h> // for dlsym()
47# include <link.h>
48# include <pthread.h>
49# include <signal.h>
50# include <sys/mman.h>
51# include <sys/resource.h>
52# include <syslog.h>
53
54# if SANITIZER_GLIBC
55# include <gnu/libc-version.h>
56# endif
57
58# if !defined(ElfW)
59# define ElfW(type) Elf_##type
60# endif
61
62# if SANITIZER_FREEBSD
63# include <pthread_np.h>
64# include <sys/auxv.h>
65# include <sys/sysctl.h>
66# define pthread_getattr_np pthread_attr_get_np
67// The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before
68// that, it was never implemented. So just define it to zero.
69# undef MAP_NORESERVE
70# define MAP_NORESERVE 0
71extern const Elf_Auxinfo *__elf_aux_vector __attribute__((weak));
72# endif
73
74# if SANITIZER_NETBSD
75# include <lwp.h>
76# include <sys/sysctl.h>
77# include <sys/tls.h>
78# endif
79
80# if SANITIZER_SOLARIS
81# include <stddef.h>
82# include <stdlib.h>
83# include <thread.h>
84# endif
85
86# if SANITIZER_HAIKU
87# include <kernel/OS.h>
88# include <sys/link_elf.h>
89# endif
90
91# if !SANITIZER_ANDROID
92# include <elf.h>
93# include <unistd.h>
94# endif
95
96namespace __sanitizer {
97
98SANITIZER_WEAK_ATTRIBUTE int real_sigaction(int signum, const void *act,
99 void *oldact);
100
101/* zig patch: use direct syscall for freebsd sigaction (sanitizer_linux.cpp) */
102# if !SANITIZER_FREEBSD
103int internal_sigaction(int signum, const void *act, void *oldact) {
104# if !SANITIZER_GO
105 if (&real_sigaction)
106 return real_sigaction(signum, act, oldact);
107# endif
108 return sigaction(signum, (const struct sigaction *)act,
109 (struct sigaction *)oldact);
110}
111# endif
112
113void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
114 uptr *stack_bottom) {
115 CHECK(stack_top);
116 CHECK(stack_bottom);
117 if (at_initialization) {
118 // This is the main thread. Libpthread may not be initialized yet.
119 struct rlimit rl;
120 CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
121
122 // Find the mapping that contains a stack variable.
123 MemoryMappingLayout proc_maps(/*cache_enabled*/ true);
124 if (proc_maps.Error()) {
125 *stack_top = *stack_bottom = 0;
126 return;
127 }
128 MemoryMappedSegment segment;
129 uptr prev_end = 0;
130 while (proc_maps.Next(&segment)) {
131 if ((uptr)&rl < segment.end)
132 break;
133 prev_end = segment.end;
134 }
135 CHECK((uptr)&rl >= segment.start && (uptr)&rl < segment.end);
136
137 // Get stacksize from rlimit, but clip it so that it does not overlap
138 // with other mappings.
139 uptr stacksize = rl.rlim_cur;
140 if (stacksize > segment.end - prev_end)
141 stacksize = segment.end - prev_end;
142 // When running with unlimited stack size, we still want to set some limit.
143 // The unlimited stack size is caused by 'ulimit -s unlimited'.
144 // Also, for some reason, GNU make spawns subprocesses with unlimited stack.
145 if (stacksize > kMaxThreadStackSize)
146 stacksize = kMaxThreadStackSize;
147 *stack_top = segment.end;
148 *stack_bottom = segment.end - stacksize;
149
150 uptr maxAddr = GetMaxUserVirtualAddress();
151 // Edge case: the stack mapping on some systems may be off-by-one e.g.,
152 // fffffffdf000-1000000000000 rw-p 00000000 00:00 0 [stack]
153 // instead of:
154 // fffffffdf000- ffffffffffff
155 // The out-of-range stack_top can result in an invalid shadow address
156 // calculation, since those usually assume the parameters are in range.
157 if (*stack_top == maxAddr + 1)
158 *stack_top = maxAddr;
159 else
160 CHECK_LE(*stack_top, maxAddr);
161
162 return;
163 }
164 uptr stacksize = 0;
165 void *stackaddr = nullptr;
166# if SANITIZER_SOLARIS
167 stack_t ss;
168 CHECK_EQ(thr_stksegment(&ss), 0);
169 stacksize = ss.ss_size;
170 stackaddr = (char *)ss.ss_sp - stacksize;
171# else // !SANITIZER_SOLARIS
172 pthread_attr_t attr;
173 pthread_attr_init(&attr);
174 CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0);
175 internal_pthread_attr_getstack(&attr, &stackaddr, &stacksize);
176 pthread_attr_destroy(&attr);
177# endif // SANITIZER_SOLARIS
178
179 *stack_top = (uptr)stackaddr + stacksize;
180 *stack_bottom = (uptr)stackaddr;
181}
182
183# if !SANITIZER_GO
184bool SetEnv(const char *name, const char *value) {
185 void *f = dlsym(RTLD_NEXT, "setenv");
186 if (!f)
187 return false;
188 typedef int (*setenv_ft)(const char *name, const char *value, int overwrite);
189 setenv_ft setenv_f;
190 CHECK_EQ(sizeof(setenv_f), sizeof(f));
191 internal_memcpy(&setenv_f, &f, sizeof(f));
192 return setenv_f(name, value, 1) == 0;
193}
194# endif
195
196// True if we can use dlpi_tls_data. glibc before 2.25 may leave NULL (BZ
197// #19826) so dlpi_tls_data cannot be used.
198//
199// musl before 1.2.3 and FreeBSD as of 12.2 incorrectly set dlpi_tls_data to
200// the TLS initialization image
201// https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=254774
202__attribute__((unused)) static int g_use_dlpi_tls_data;
203
204# if SANITIZER_GLIBC && !SANITIZER_GO
205static void GetGLibcVersion(int *major, int *minor, int *patch) {
206 const char *p = gnu_get_libc_version();
207 *major = internal_simple_strtoll(p, &p, 10);
208 // Caller does not expect anything else.
209 CHECK_EQ(*major, 2);
210 *minor = (*p == '.') ? internal_simple_strtoll(p + 1, &p, 10) : 0;
211 *patch = (*p == '.') ? internal_simple_strtoll(p + 1, &p, 10) : 0;
212}
213
214static uptr ThreadDescriptorSizeFallback() {
215# if defined(__x86_64__) || defined(__i386__) || defined(__arm__) || \
216 SANITIZER_RISCV64
217 int major;
218 int minor;
219 int patch;
220 GetGLibcVersion(&major, &minor, &patch);
221# endif
222
223# if defined(__x86_64__) || defined(__i386__) || defined(__arm__)
224 /* sizeof(struct pthread) values from various glibc versions. */
225 if (SANITIZER_X32)
226 return 1728; // Assume only one particular version for x32.
227 // For ARM sizeof(struct pthread) changed in Glibc 2.23.
228 if (SANITIZER_ARM)
229 return minor <= 22 ? 1120 : 1216;
230 if (minor <= 3)
231 return FIRST_32_SECOND_64(1104, 1696);
232 if (minor == 4)
233 return FIRST_32_SECOND_64(1120, 1728);
234 if (minor == 5)
235 return FIRST_32_SECOND_64(1136, 1728);
236 if (minor <= 9)
237 return FIRST_32_SECOND_64(1136, 1712);
238 if (minor == 10)
239 return FIRST_32_SECOND_64(1168, 1776);
240 if (minor == 11 || (minor == 12 && patch == 1))
241 return FIRST_32_SECOND_64(1168, 2288);
242 if (minor <= 14)
243 return FIRST_32_SECOND_64(1168, 2304);
244 if (minor < 32) // Unknown version
245 return FIRST_32_SECOND_64(1216, 2304);
246 // minor == 32
247 return FIRST_32_SECOND_64(1344, 2496);
248# endif
249
250# if SANITIZER_RISCV64
251 // TODO: consider adding an optional runtime check for an unknown (untested)
252 // glibc version
253 if (minor <= 28) // WARNING: the highest tested version is 2.29
254 return 1772; // no guarantees for this one
255 if (minor <= 31)
256 return 1772; // tested against glibc 2.29, 2.31
257 return 1936; // tested against glibc 2.32
258# endif
259
260# if defined(__s390__) || defined(__sparc__)
261 // The size of a prefix of TCB including pthread::{specific_1stblock,specific}
262 // suffices. Just return offsetof(struct pthread, specific_used), which hasn't
263 // changed since 2007-05. Technically this applies to i386/x86_64 as well but
264 // we call _dl_get_tls_static_info and need the precise size of struct
265 // pthread.
266 return FIRST_32_SECOND_64(524, 1552);
267# endif
268
269# if defined(__mips__)
270 // TODO(sagarthakur): add more values as per different glibc versions.
271 return FIRST_32_SECOND_64(1152, 1776);
272# endif
273
274# if SANITIZER_LOONGARCH64
275 return 1856; // from glibc 2.36
276# endif
277
278# if defined(__aarch64__)
279 // The sizeof (struct pthread) is the same from GLIBC 2.17 to 2.22.
280 return 1776;
281# endif
282
283# if defined(__powerpc64__)
284 return 1776; // from glibc.ppc64le 2.20-8.fc21
285# endif
286}
287# endif // SANITIZER_GLIBC && !SANITIZER_GO
288
289# if SANITIZER_FREEBSD && !SANITIZER_GO
290// FIXME: Implementation is very GLIBC specific, but it's used by FreeBSD.
291static uptr ThreadDescriptorSizeFallback() {
292# if defined(__s390__) || defined(__sparc__)
293 // The size of a prefix of TCB including pthread::{specific_1stblock,specific}
294 // suffices. Just return offsetof(struct pthread, specific_used), which hasn't
295 // changed since 2007-05. Technically this applies to i386/x86_64 as well but
296 // we call _dl_get_tls_static_info and need the precise size of struct
297 // pthread.
298 return FIRST_32_SECOND_64(524, 1552);
299# endif
300
301# if defined(__mips__)
302 // TODO(sagarthakur): add more values as per different glibc versions.
303 return FIRST_32_SECOND_64(1152, 1776);
304# endif
305
306# if SANITIZER_LOONGARCH64
307 return 1856; // from glibc 2.36
308# endif
309
310# if defined(__aarch64__)
311 // The sizeof (struct pthread) is the same from GLIBC 2.17 to 2.22.
312 return 1776;
313# endif
314
315# if defined(__powerpc64__)
316 return 1776; // from glibc.ppc64le 2.20-8.fc21
317# endif
318
319 return 0;
320}
321# endif // SANITIZER_FREEBSD && !SANITIZER_GO
322
323# if (SANITIZER_FREEBSD || SANITIZER_GLIBC) && !SANITIZER_GO
324// On glibc x86_64, ThreadDescriptorSize() needs to be precise due to the usage
325// of g_tls_size. On other targets, ThreadDescriptorSize() is only used by lsan
326// to get the pointer to thread-specific data keys in the thread control block.
327// sizeof(struct pthread) from glibc.
328static uptr thread_descriptor_size;
329
330uptr ThreadDescriptorSize() { return thread_descriptor_size; }
331
332# if SANITIZER_GLIBC
333__attribute__((unused)) static size_t g_tls_size;
334# endif
335
336void InitTlsSize() {
337# if SANITIZER_GLIBC
338 int major, minor, patch;
339 GetGLibcVersion(&major, &minor, &patch);
340 g_use_dlpi_tls_data = major == 2 && minor >= 25;
341
342 if (major == 2 && minor >= 34) {
343 // _thread_db_sizeof_pthread is a GLIBC_PRIVATE symbol that is exported in
344 // glibc 2.34 and later.
345 if (unsigned *psizeof = static_cast<unsigned *>(
346 dlsym(RTLD_DEFAULT, "_thread_db_sizeof_pthread"))) {
347 thread_descriptor_size = *psizeof;
348 }
349 }
350
351# if defined(__aarch64__) || defined(__x86_64__) || \
352 defined(__powerpc64__) || defined(__loongarch__)
353 auto *get_tls_static_info = (void (*)(size_t *, size_t *))dlsym(
354 RTLD_DEFAULT, "_dl_get_tls_static_info");
355 size_t tls_align;
356 // Can be null if static link.
357 if (get_tls_static_info)
358 get_tls_static_info(&g_tls_size, &tls_align);
359# endif
360
361# endif // SANITIZER_GLIBC
362
363 if (!thread_descriptor_size)
364 thread_descriptor_size = ThreadDescriptorSizeFallback();
365}
366
367# if defined(__mips__) || defined(__powerpc64__) || SANITIZER_RISCV64 || \
368 SANITIZER_LOONGARCH64
369// TlsPreTcbSize includes size of struct pthread_descr and size of tcb
370// head structure. It lies before the static tls blocks.
371static uptr TlsPreTcbSize() {
372# if defined(__mips__)
373 const uptr kTcbHead = 16; // sizeof (tcbhead_t)
374# elif defined(__powerpc64__)
375 const uptr kTcbHead = 88; // sizeof (tcbhead_t)
376# elif SANITIZER_RISCV64
377 const uptr kTcbHead = 16; // sizeof (tcbhead_t)
378# elif SANITIZER_LOONGARCH64
379 const uptr kTcbHead = 16; // sizeof (tcbhead_t)
380# endif
381 const uptr kTlsAlign = 16;
382 const uptr kTlsPreTcbSize =
383 RoundUpTo(ThreadDescriptorSize() + kTcbHead, kTlsAlign);
384 return kTlsPreTcbSize;
385}
386# endif
387# else // (SANITIZER_FREEBSD || SANITIZER_GLIBC) && !SANITIZER_GO
388void InitTlsSize() {}
389uptr ThreadDescriptorSize() { return 0; }
390# endif // (SANITIZER_FREEBSD || SANITIZER_GLIBC) && !SANITIZER_GO
391
392# if (SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_SOLARIS) && \
393 !SANITIZER_ANDROID && !SANITIZER_GO
394namespace {
395struct TlsBlock {
396 uptr begin, end, align;
397 size_t tls_modid;
398 bool operator<(const TlsBlock &rhs) const { return begin < rhs.begin; }
399};
400} // namespace
401
402# ifdef __s390__
403extern "C" uptr __tls_get_offset(void *arg);
404
405static uptr TlsGetOffset(uptr ti_module, uptr ti_offset) {
406 // The __tls_get_offset ABI requires %r12 to point to GOT and %r2 to be an
407 // offset of a struct tls_index inside GOT. We don't possess either of the
408 // two, so violate the letter of the "ELF Handling For Thread-Local
409 // Storage" document and assume that the implementation just dereferences
410 // %r2 + %r12.
411 uptr tls_index[2] = {ti_module, ti_offset};
412 register uptr r2 asm("2") = 0;
413 register void *r12 asm("12") = tls_index;
414 asm("basr %%r14, %[__tls_get_offset]"
415 : "+r"(r2)
416 : [__tls_get_offset] "r"(__tls_get_offset), "r"(r12)
417 : "memory", "cc", "0", "1", "3", "4", "5", "14");
418 return r2;
419}
420# else
421extern "C" void *__tls_get_addr(size_t *);
422# endif
423
424static size_t main_tls_modid;
425
426static int CollectStaticTlsBlocks(struct dl_phdr_info *info, size_t size,
427 void *data) {
428 size_t tls_modid;
429# if SANITIZER_SOLARIS
430 // dlpi_tls_modid is only available since Solaris 11.4 SRU 10. Use
431 // dlinfo(RTLD_DI_LINKMAP) instead which works on all of Solaris 11.3,
432 // 11.4, and Illumos. The tlsmodid of the executable was changed to 1 in
433 // 11.4 to match other implementations.
434 if (size >= offsetof(dl_phdr_info_test, dlpi_tls_modid))
435 main_tls_modid = 1;
436 else
437 main_tls_modid = 0;
438 g_use_dlpi_tls_data = 0;
439 Rt_map *map;
440 dlinfo(RTLD_SELF, RTLD_DI_LINKMAP, &map);
441 tls_modid = map->rt_tlsmodid;
442# else
443 main_tls_modid = 1;
444 tls_modid = info->dlpi_tls_modid;
445# endif
446
447 if (tls_modid < main_tls_modid)
448 return 0;
449 uptr begin;
450# if !SANITIZER_SOLARIS
451 begin = (uptr)info->dlpi_tls_data;
452# endif
453 if (!g_use_dlpi_tls_data) {
454 // Call __tls_get_addr as a fallback. This forces TLS allocation on glibc
455 // and FreeBSD.
456# ifdef __s390__
457 begin = (uptr)__builtin_thread_pointer() + TlsGetOffset(tls_modid, 0);
458# else
459 size_t mod_and_off[2] = {tls_modid, 0};
460 begin = (uptr)__tls_get_addr(mod_and_off);
461# endif
462 }
463 for (unsigned i = 0; i != info->dlpi_phnum; ++i)
464 if (info->dlpi_phdr[i].p_type == PT_TLS) {
465 static_cast<InternalMmapVector<TlsBlock> *>(data)->push_back(
466 TlsBlock{begin, begin + info->dlpi_phdr[i].p_memsz,
467 info->dlpi_phdr[i].p_align, tls_modid});
468 break;
469 }
470 return 0;
471}
472
473__attribute__((unused)) static void GetStaticTlsBoundary(uptr *addr, uptr *size,
474 uptr *align) {
475 InternalMmapVector<TlsBlock> ranges;
476 dl_iterate_phdr(CollectStaticTlsBlocks, &ranges);
477 uptr len = ranges.size();
478 Sort(ranges.begin(), len);
479 // Find the range with tls_modid == main_tls_modid. For glibc, because
480 // libc.so uses PT_TLS, this module is guaranteed to exist and is one of
481 // the initially loaded modules.
482 uptr one = 0;
483 while (one != len && ranges[one].tls_modid != main_tls_modid) ++one;
484 if (one == len) {
485 // This may happen with musl if no module uses PT_TLS.
486 *addr = 0;
487 *size = 0;
488 *align = 1;
489 return;
490 }
491 // Find the maximum consecutive ranges. We consider two modules consecutive if
492 // the gap is smaller than the alignment of the latter range. The dynamic
493 // loader places static TLS blocks this way not to waste space.
494 uptr l = one;
495 *align = ranges[l].align;
496 while (l != 0 && ranges[l].begin < ranges[l - 1].end + ranges[l].align)
497 *align = Max(*align, ranges[--l].align);
498 uptr r = one + 1;
499 while (r != len && ranges[r].begin < ranges[r - 1].end + ranges[r].align)
500 *align = Max(*align, ranges[r++].align);
501 *addr = ranges[l].begin;
502 *size = ranges[r - 1].end - ranges[l].begin;
503}
504# endif // (x86_64 || i386 || mips || ...) && (SANITIZER_FREEBSD ||
505 // SANITIZER_LINUX) && !SANITIZER_ANDROID && !SANITIZER_GO
506
507# if SANITIZER_NETBSD
508static struct tls_tcb *ThreadSelfTlsTcb() {
509 struct tls_tcb *tcb = nullptr;
510# ifdef __HAVE___LWP_GETTCB_FAST
511 tcb = (struct tls_tcb *)__lwp_gettcb_fast();
512# elif defined(__HAVE___LWP_GETPRIVATE_FAST)
513 tcb = (struct tls_tcb *)__lwp_getprivate_fast();
514# endif
515 return tcb;
516}
517
518uptr ThreadSelf() { return (uptr)ThreadSelfTlsTcb()->tcb_pthread; }
519
520int GetSizeFromHdr(struct dl_phdr_info *info, size_t size, void *data) {
521 const Elf_Phdr *hdr = info->dlpi_phdr;
522 const Elf_Phdr *last_hdr = hdr + info->dlpi_phnum;
523
524 for (; hdr != last_hdr; ++hdr) {
525 if (hdr->p_type == PT_TLS && info->dlpi_tls_modid == 1) {
526 *(uptr *)data = hdr->p_memsz;
527 break;
528 }
529 }
530 return 0;
531}
532# endif // SANITIZER_NETBSD
533
534# if SANITIZER_ANDROID
535// Bionic provides this API since S.
536extern "C" SANITIZER_WEAK_ATTRIBUTE void __libc_get_static_tls_bounds(void **,
537 void **);
538# endif
539
540# if !SANITIZER_GO
541static void GetTls(uptr *addr, uptr *size) {
542# if SANITIZER_ANDROID
543 if (&__libc_get_static_tls_bounds) {
544 void *start_addr;
545 void *end_addr;
546 __libc_get_static_tls_bounds(&start_addr, &end_addr);
547 *addr = reinterpret_cast<uptr>(start_addr);
548 *size =
549 reinterpret_cast<uptr>(end_addr) - reinterpret_cast<uptr>(start_addr);
550 } else {
551 *addr = 0;
552 *size = 0;
553 }
554# elif SANITIZER_GLIBC && defined(__x86_64__)
555 // For aarch64 and x86-64, use an O(1) approach which requires relatively
556 // precise ThreadDescriptorSize. g_tls_size was initialized in InitTlsSize.
557# if SANITIZER_X32
558 asm("mov %%fs:8,%0" : "=r"(*addr));
559# else
560 asm("mov %%fs:16,%0" : "=r"(*addr));
561# endif
562 *size = g_tls_size;
563 *addr -= *size;
564 *addr += ThreadDescriptorSize();
565# elif SANITIZER_GLIBC && defined(__aarch64__)
566 *addr = reinterpret_cast<uptr>(__builtin_thread_pointer()) -
567 ThreadDescriptorSize();
568 *size = g_tls_size + ThreadDescriptorSize();
569# elif SANITIZER_GLIBC && defined(__loongarch__)
570# ifdef __clang__
571 *addr = reinterpret_cast<uptr>(__builtin_thread_pointer()) -
572 ThreadDescriptorSize();
573# else
574 asm("or %0,$tp,$zero" : "=r"(*addr));
575 *addr -= ThreadDescriptorSize();
576# endif
577 *size = g_tls_size + ThreadDescriptorSize();
578# elif SANITIZER_GLIBC && defined(__powerpc64__)
579 // Workaround for glibc<2.25(?). 2.27 is known to not need this.
580 uptr tp;
581 asm("addi %0,13,-0x7000" : "=r"(tp));
582 const uptr pre_tcb_size = TlsPreTcbSize();
583 *addr = tp - pre_tcb_size;
584 *size = g_tls_size + pre_tcb_size;
585# elif SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_SOLARIS
586 uptr align;
587 GetStaticTlsBoundary(addr, size, &align);
588# if defined(__x86_64__) || defined(__i386__) || defined(__s390__) || \
589 defined(__sparc__)
590 if (SANITIZER_GLIBC) {
591# if defined(__x86_64__) || defined(__i386__)
592 align = Max<uptr>(align, 64);
593# else
594 align = Max<uptr>(align, 16);
595# endif
596 }
597 const uptr tp = RoundUpTo(*addr + *size, align);
598
599 // lsan requires the range to additionally cover the static TLS surplus
600 // (elf/dl-tls.c defines 1664). Otherwise there may be false positives for
601 // allocations only referenced by tls in dynamically loaded modules.
602 if (SANITIZER_GLIBC)
603 *size += 1644;
604 else if (SANITIZER_FREEBSD)
605 *size += 128; // RTLD_STATIC_TLS_EXTRA
606
607 // Extend the range to include the thread control block. On glibc, lsan needs
608 // the range to include pthread::{specific_1stblock,specific} so that
609 // allocations only referenced by pthread_setspecific can be scanned. This may
610 // underestimate by at most TLS_TCB_ALIGN-1 bytes but it should be fine
611 // because the number of bytes after pthread::specific is larger.
612 *addr = tp - RoundUpTo(*size, align);
613 *size = tp - *addr + ThreadDescriptorSize();
614# else
615# if SANITIZER_GLIBC
616 *size += 1664;
617# elif SANITIZER_FREEBSD
618 *size += 128; // RTLD_STATIC_TLS_EXTRA
619# if defined(__mips__) || defined(__powerpc64__) || SANITIZER_RISCV64
620 const uptr pre_tcb_size = TlsPreTcbSize();
621 *addr -= pre_tcb_size;
622 *size += pre_tcb_size;
623# else
624 // arm and aarch64 reserve two words at TP, so this underestimates the range.
625 // However, this is sufficient for the purpose of finding the pointers to
626 // thread-specific data keys.
627 const uptr tcb_size = ThreadDescriptorSize();
628 *addr -= tcb_size;
629 *size += tcb_size;
630# endif
631# endif
632# endif
633# elif SANITIZER_NETBSD
634 struct tls_tcb *const tcb = ThreadSelfTlsTcb();
635 *addr = 0;
636 *size = 0;
637 if (tcb != 0) {
638 // Find size (p_memsz) of dlpi_tls_modid 1 (TLS block of the main program).
639 // ld.elf_so hardcodes the index 1.
640 dl_iterate_phdr(GetSizeFromHdr, size);
641
642 if (*size != 0) {
643 // The block has been found and tcb_dtv[1] contains the base address
644 *addr = (uptr)tcb->tcb_dtv[1];
645 }
646 }
647# elif SANITIZER_HAIKU
648# else
649# error "Unknown OS"
650# endif
651}
652# endif
653
654# if !SANITIZER_GO
655uptr GetTlsSize() {
656# if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \
657 SANITIZER_SOLARIS
658 uptr addr, size;
659 GetTls(&addr, &size);
660 return size;
661# else
662 return 0;
663# endif
664}
665# endif
666
667void GetThreadStackAndTls(bool main, uptr *stk_begin, uptr *stk_end,
668 uptr *tls_begin, uptr *tls_end) {
669# if SANITIZER_GO
670 // Stub implementation for Go.
671 *stk_begin = 0;
672 *stk_end = 0;
673 *tls_begin = 0;
674 *tls_end = 0;
675# else
676 uptr tls_addr = 0;
677 uptr tls_size = 0;
678 GetTls(&tls_addr, &tls_size);
679 *tls_begin = tls_addr;
680 *tls_end = tls_addr + tls_size;
681
682 uptr stack_top, stack_bottom;
683 GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
684 *stk_begin = stack_bottom;
685 *stk_end = stack_top;
686
687 if (!main) {
688 // If stack and tls intersect, make them non-intersecting.
689 if (*tls_begin > *stk_begin && *tls_begin < *stk_end) {
690 if (*stk_end < *tls_end)
691 *tls_end = *stk_end;
692 *stk_end = *tls_begin;
693 }
694 }
695# endif
696}
697
698# if !SANITIZER_FREEBSD
699typedef ElfW(Phdr) Elf_Phdr;
700# endif
701
702struct DlIteratePhdrData {
703 InternalMmapVectorNoCtor<LoadedModule> *modules;
704 bool first;
705};
706
707static int AddModuleSegments(const char *module_name, dl_phdr_info *info,
708 InternalMmapVectorNoCtor<LoadedModule> *modules) {
709 if (module_name[0] == '\0')
710 return 0;
711 LoadedModule cur_module;
712 cur_module.set(module_name, info->dlpi_addr);
713 for (int i = 0; i < (int)info->dlpi_phnum; i++) {
714 const Elf_Phdr *phdr = &info->dlpi_phdr[i];
715 if (phdr->p_type == PT_LOAD) {
716 uptr cur_beg = info->dlpi_addr + phdr->p_vaddr;
717 uptr cur_end = cur_beg + phdr->p_memsz;
718# if SANITIZER_HAIKU
719 bool executable = phdr->p_flags & PF_EXECUTE;
720 bool writable = phdr->p_flags & PF_WRITE;
721# else
722 bool executable = phdr->p_flags & PF_X;
723 bool writable = phdr->p_flags & PF_W;
724# endif
725 cur_module.addAddressRange(cur_beg, cur_end, executable, writable);
726 } else if (phdr->p_type == PT_NOTE) {
727# ifdef NT_GNU_BUILD_ID
728 uptr off = 0;
729 while (off + sizeof(ElfW(Nhdr)) < phdr->p_memsz) {
730 auto *nhdr = reinterpret_cast<const ElfW(Nhdr) *>(info->dlpi_addr +
731 phdr->p_vaddr + off);
732 constexpr auto kGnuNamesz = 4; // "GNU" with NUL-byte.
733 static_assert(kGnuNamesz % 4 == 0, "kGnuNameSize is aligned to 4.");
734 if (nhdr->n_type == NT_GNU_BUILD_ID && nhdr->n_namesz == kGnuNamesz) {
735 if (off + sizeof(ElfW(Nhdr)) + nhdr->n_namesz + nhdr->n_descsz >
736 phdr->p_memsz) {
737 // Something is very wrong, bail out instead of reading potentially
738 // arbitrary memory.
739 break;
740 }
741 const char *name =
742 reinterpret_cast<const char *>(nhdr) + sizeof(*nhdr);
743 if (internal_memcmp(name, "GNU", 3) == 0) {
744 const char *value = reinterpret_cast<const char *>(nhdr) +
745 sizeof(*nhdr) + kGnuNamesz;
746 cur_module.setUuid(value, nhdr->n_descsz);
747 break;
748 }
749 }
750 off += sizeof(*nhdr) + RoundUpTo(nhdr->n_namesz, 4) +
751 RoundUpTo(nhdr->n_descsz, 4);
752 }
753# endif
754 }
755 }
756 modules->push_back(cur_module);
757 return 0;
758}
759
760static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
761 DlIteratePhdrData *data = (DlIteratePhdrData *)arg;
762 if (data->first) {
763 InternalMmapVector<char> module_name(kMaxPathLength);
764 data->first = false;
765 // First module is the binary itself.
766 ReadBinaryNameCached(module_name.data(), module_name.size());
767 return AddModuleSegments(module_name.data(), info, data->modules);
768 }
769
770 if (info->dlpi_name)
771 return AddModuleSegments(info->dlpi_name, info, data->modules);
772
773 return 0;
774}
775
776void ListOfModules::init() {
777 clearOrInit();
778 DlIteratePhdrData data = {&modules_, true};
779 dl_iterate_phdr(dl_iterate_phdr_cb, &data);
780}
781
782void ListOfModules::fallbackInit() { clear(); }
783
784// getrusage does not give us the current RSS, only the max RSS.
785// Still, this is better than nothing if /proc/self/statm is not available
786// for some reason, e.g. due to a sandbox.
787static uptr GetRSSFromGetrusage() {
788 struct rusage usage;
789 if (getrusage(RUSAGE_SELF, &usage)) // Failed, probably due to a sandbox.
790 return 0;
791 return usage.ru_maxrss << 10; // ru_maxrss is in Kb.
792}
793
794uptr GetRSS() {
795 if (!common_flags()->can_use_proc_maps_statm)
796 return GetRSSFromGetrusage();
797 fd_t fd = OpenFile("/proc/self/statm", RdOnly);
798 if (fd == kInvalidFd)
799 return GetRSSFromGetrusage();
800 char buf[64];
801 uptr len = internal_read(fd, buf, sizeof(buf) - 1);
802 internal_close(fd);
803 if ((sptr)len <= 0)
804 return 0;
805 buf[len] = 0;
806 // The format of the file is:
807 // 1084 89 69 11 0 79 0
808 // We need the second number which is RSS in pages.
809 char *pos = buf;
810 // Skip the first number.
811 while (*pos >= '0' && *pos <= '9') pos++;
812 // Skip whitespaces.
813 while (!(*pos >= '0' && *pos <= '9') && *pos != 0) pos++;
814 // Read the number.
815 uptr rss = 0;
816 while (*pos >= '0' && *pos <= '9') rss = rss * 10 + *pos++ - '0';
817 return rss * GetPageSizeCached();
818}
819
820// sysconf(_SC_NPROCESSORS_{CONF,ONLN}) cannot be used on most platforms as
821// they allocate memory.
822u32 GetNumberOfCPUs() {
823# if SANITIZER_FREEBSD || SANITIZER_NETBSD
824 u32 ncpu;
825 int req[2];
826 uptr len = sizeof(ncpu);
827 req[0] = CTL_HW;
828# ifdef HW_NCPUONLINE
829 req[1] = HW_NCPUONLINE;
830# else
831 req[1] = HW_NCPU;
832# endif
833 CHECK_EQ(internal_sysctl(req, 2, &ncpu, &len, NULL, 0), 0);
834 return ncpu;
835# elif SANITIZER_HAIKU
836 system_info info;
837 get_system_info(&info);
838 return info.cpu_count;
839# elif SANITIZER_SOLARIS
840 return sysconf(_SC_NPROCESSORS_ONLN);
841# else
842 cpu_set_t CPUs;
843 CHECK_EQ(sched_getaffinity(0, sizeof(cpu_set_t), &CPUs), 0);
844 return CPU_COUNT(&CPUs);
845# endif
846}
847
848# if SANITIZER_LINUX
849
850# if SANITIZER_ANDROID
851static atomic_uint8_t android_log_initialized;
852
853void AndroidLogInit() {
854 openlog(GetProcessName(), 0, LOG_USER);
855 atomic_store(&android_log_initialized, 1, memory_order_release);
856}
857
858static bool ShouldLogAfterPrintf() {
859 return atomic_load(&android_log_initialized, memory_order_acquire);
860}
861
862extern "C" SANITIZER_WEAK_ATTRIBUTE int async_safe_write_log(int pri,
863 const char *tag,
864 const char *msg);
865extern "C" SANITIZER_WEAK_ATTRIBUTE int __android_log_write(int prio,
866 const char *tag,
867 const char *msg);
868
869// ANDROID_LOG_INFO is 4, but can't be resolved at runtime.
870# define SANITIZER_ANDROID_LOG_INFO 4
871
872// async_safe_write_log is a new public version of __libc_write_log that is
873// used behind syslog. It is preferable to syslog as it will not do any dynamic
874// memory allocation or formatting.
875// If the function is not available, syslog is preferred for L+ (it was broken
876// pre-L) as __android_log_write triggers a racey behavior with the strncpy
877// interceptor. Fallback to __android_log_write pre-L.
878void WriteOneLineToSyslog(const char *s) {
879 if (&async_safe_write_log) {
880 async_safe_write_log(SANITIZER_ANDROID_LOG_INFO, GetProcessName(), s);
881 } else {
882 syslog(LOG_INFO, "%s", s);
883 }
884}
885
886extern "C" SANITIZER_WEAK_ATTRIBUTE void android_set_abort_message(
887 const char *);
888
889void SetAbortMessage(const char *str) {
890 if (&android_set_abort_message)
891 android_set_abort_message(str);
892}
893# else
894void AndroidLogInit() {}
895
896static bool ShouldLogAfterPrintf() { return true; }
897
898void WriteOneLineToSyslog(const char *s) { syslog(LOG_INFO, "%s", s); }
899
900void SetAbortMessage(const char *str) {}
901# endif // SANITIZER_ANDROID
902
903void LogMessageOnPrintf(const char *str) {
904 if (common_flags()->log_to_syslog && ShouldLogAfterPrintf())
905 WriteToSyslog(str);
906}
907
908# endif // SANITIZER_LINUX
909
910# if SANITIZER_GLIBC && !SANITIZER_GO
911// glibc crashes when using clock_gettime from a preinit_array function as the
912// vDSO function pointers haven't been initialized yet. __progname is
913// initialized after the vDSO function pointers, so if it exists, is not null
914// and is not empty, we can use clock_gettime.
915extern "C" SANITIZER_WEAK_ATTRIBUTE char *__progname;
916inline bool CanUseVDSO() { return &__progname && __progname && *__progname; }
917
918// MonotonicNanoTime is a timing function that can leverage the vDSO by calling
919// clock_gettime. real_clock_gettime only exists if clock_gettime is
920// intercepted, so define it weakly and use it if available.
921extern "C" SANITIZER_WEAK_ATTRIBUTE int real_clock_gettime(u32 clk_id,
922 void *tp);
923u64 MonotonicNanoTime() {
924 timespec ts;
925 if (CanUseVDSO()) {
926 if (&real_clock_gettime)
927 real_clock_gettime(CLOCK_MONOTONIC, &ts);
928 else
929 clock_gettime(CLOCK_MONOTONIC, &ts);
930 } else {
931 internal_clock_gettime(CLOCK_MONOTONIC, &ts);
932 }
933 return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
934}
935# else
936// Non-glibc & Go always use the regular function.
937u64 MonotonicNanoTime() {
938 timespec ts;
939 clock_gettime(CLOCK_MONOTONIC, &ts);
940 return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
941}
942# endif // SANITIZER_GLIBC && !SANITIZER_GO
943
944void ReExec() {
945 const char *pathname = "/proc/self/exe";
946
947# if SANITIZER_FREEBSD
948 for (const auto *aux = __elf_aux_vector; aux->a_type != AT_NULL; aux++) {
949 if (aux->a_type == AT_EXECPATH) {
950 pathname = static_cast<const char *>(aux->a_un.a_ptr);
951 break;
952 }
953 }
954# elif SANITIZER_NETBSD
955 static const int name[] = {
956 CTL_KERN,
957 KERN_PROC_ARGS,
958 -1,
959 KERN_PROC_PATHNAME,
960 };
961 char path[400];
962 uptr len;
963
964 len = sizeof(path);
965 if (internal_sysctl(name, ARRAY_SIZE(name), path, &len, NULL, 0) != -1)
966 pathname = path;
967# elif SANITIZER_SOLARIS
968 pathname = getexecname();
969 CHECK_NE(pathname, NULL);
970# elif SANITIZER_USE_GETAUXVAL
971 // Calling execve with /proc/self/exe sets that as $EXEC_ORIGIN. Binaries that
972 // rely on that will fail to load shared libraries. Query AT_EXECFN instead.
973 pathname = reinterpret_cast<const char *>(getauxval(AT_EXECFN));
974# endif
975
976 uptr rv = internal_execve(pathname, GetArgv(), GetEnviron());
977 int rverrno;
978 CHECK_EQ(internal_iserror(rv, &rverrno), true);
979 Printf("execve failed, errno %d\n", rverrno);
980 Die();
981}
982
983void UnmapFromTo(uptr from, uptr to) {
984 if (to == from)
985 return;
986 CHECK(to >= from);
987 uptr res = internal_munmap(reinterpret_cast<void *>(from), to - from);
988 if (UNLIKELY(internal_iserror(res))) {
989 Report("ERROR: %s failed to unmap 0x%zx (%zd) bytes at address %p\n",
990 SanitizerToolName, to - from, to - from, (void *)from);
991 CHECK("unable to unmap" && 0);
992 }
993}
994
995uptr MapDynamicShadow(uptr shadow_size_bytes, uptr shadow_scale,
996 uptr min_shadow_base_alignment, UNUSED uptr &high_mem_end,
997 uptr granularity) {
998 const uptr alignment =
999 Max<uptr>(granularity << shadow_scale, 1ULL << min_shadow_base_alignment);
1000 const uptr left_padding =
1001 Max<uptr>(granularity, 1ULL << min_shadow_base_alignment);
1002
1003 const uptr shadow_size = RoundUpTo(shadow_size_bytes, granularity);
1004 const uptr map_size = shadow_size + left_padding + alignment;
1005
1006 const uptr map_start = (uptr)MmapNoAccess(map_size);
1007 CHECK_NE(map_start, ~(uptr)0);
1008
1009 const uptr shadow_start = RoundUpTo(map_start + left_padding, alignment);
1010
1011 UnmapFromTo(map_start, shadow_start - left_padding);
1012 UnmapFromTo(shadow_start + shadow_size, map_start + map_size);
1013
1014 return shadow_start;
1015}
1016
1017static uptr MmapSharedNoReserve(uptr addr, uptr size) {
1018 return internal_mmap(
1019 reinterpret_cast<void *>(addr), size, PROT_READ | PROT_WRITE,
1020 MAP_FIXED | MAP_SHARED | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
1021}
1022
1023static uptr MremapCreateAlias(uptr base_addr, uptr alias_addr,
1024 uptr alias_size) {
1025# if SANITIZER_LINUX
1026 return internal_mremap(reinterpret_cast<void *>(base_addr), 0, alias_size,
1027 MREMAP_MAYMOVE | MREMAP_FIXED,
1028 reinterpret_cast<void *>(alias_addr));
1029# else
1030 CHECK(false && "mremap is not supported outside of Linux");
1031 return 0;
1032# endif
1033}
1034
1035static void CreateAliases(uptr start_addr, uptr alias_size, uptr num_aliases) {
1036 uptr total_size = alias_size * num_aliases;
1037 uptr mapped = MmapSharedNoReserve(start_addr, total_size);
1038 CHECK_EQ(mapped, start_addr);
1039
1040 for (uptr i = 1; i < num_aliases; ++i) {
1041 uptr alias_addr = start_addr + i * alias_size;
1042 CHECK_EQ(MremapCreateAlias(start_addr, alias_addr, alias_size), alias_addr);
1043 }
1044}
1045
1046uptr MapDynamicShadowAndAliases(uptr shadow_size, uptr alias_size,
1047 uptr num_aliases, uptr ring_buffer_size) {
1048 CHECK_EQ(alias_size & (alias_size - 1), 0);
1049 CHECK_EQ(num_aliases & (num_aliases - 1), 0);
1050 CHECK_EQ(ring_buffer_size & (ring_buffer_size - 1), 0);
1051
1052 const uptr granularity = GetMmapGranularity();
1053 shadow_size = RoundUpTo(shadow_size, granularity);
1054 CHECK_EQ(shadow_size & (shadow_size - 1), 0);
1055
1056 const uptr alias_region_size = alias_size * num_aliases;
1057 const uptr alignment =
1058 2 * Max(Max(shadow_size, alias_region_size), ring_buffer_size);
1059 const uptr left_padding = ring_buffer_size;
1060
1061 const uptr right_size = alignment;
1062 const uptr map_size = left_padding + 2 * alignment;
1063
1064 const uptr map_start = reinterpret_cast<uptr>(MmapNoAccess(map_size));
1065 CHECK_NE(map_start, static_cast<uptr>(-1));
1066 const uptr right_start = RoundUpTo(map_start + left_padding, alignment);
1067
1068 UnmapFromTo(map_start, right_start - left_padding);
1069 UnmapFromTo(right_start + right_size, map_start + map_size);
1070
1071 CreateAliases(right_start + right_size / 2, alias_size, num_aliases);
1072
1073 return right_start;
1074}
1075
1076void InitializePlatformCommonFlags(CommonFlags *cf) {
1077# if SANITIZER_ANDROID
1078 if (&__libc_get_static_tls_bounds == nullptr)
1079 cf->detect_leaks = false;
1080# endif
1081}
1082
1083} // namespace __sanitizer
1084
1085#endif