1 //===-- asan_linux.cc -----------------------------------------------------===//
3 // This file is distributed under the University of Illinois Open Source
4 // License. See LICENSE.TXT for details.
6 //===----------------------------------------------------------------------===//
8 // This file is a part of AddressSanitizer, an address sanity checker.
10 // Linux-specific details.
11 //===----------------------------------------------------------------------===//
13 #include "sanitizer_common/sanitizer_platform.h"
14 #if SANITIZER_FREEBSD || SANITIZER_LINUX
16 #include "asan_interceptors.h"
17 #include "asan_internal.h"
18 #include "asan_thread.h"
19 #include "sanitizer_common/sanitizer_flags.h"
20 #include "sanitizer_common/sanitizer_freebsd.h"
21 #include "sanitizer_common/sanitizer_libc.h"
22 #include "sanitizer_common/sanitizer_procmaps.h"
25 #include <sys/resource.h>
27 #include <sys/syscall.h>
28 #include <sys/types.h>
37 #include <sys/link_elf.h>
40 #if SANITIZER_ANDROID || SANITIZER_FREEBSD
42 extern "C" void* _DYNAMIC
;
44 #include <sys/ucontext.h>
48 // x86-64 FreeBSD 9.2 and older define 'ucontext_t' incorrectly in
50 #if SANITIZER_FREEBSD && (SANITIZER_WORDSIZE == 32) && \
51 __FreeBSD_version <= 902001 // v9.2
52 #define ucontext_t xucontext_t
56 ASAN_RT_VERSION_UNDEFINED
= 0,
57 ASAN_RT_VERSION_DYNAMIC
,
58 ASAN_RT_VERSION_STATIC
,
61 // FIXME: perhaps also store abi version here?
63 SANITIZER_INTERFACE_ATTRIBUTE
64 asan_rt_version_t __asan_rt_version
;
69 void InitializePlatformInterceptors() {}
70 void InitializePlatformExceptionHandlers() {}
72 void *AsanDoesNotSupportStaticLinkage() {
73 // This will fail to link with -static.
74 return &_DYNAMIC
; // defined in link.h
77 void AsanApplyToGlobals(globals_op_fptr op
, const void *needle
) {
82 // FIXME: should we do anything for Android?
83 void AsanCheckDynamicRTPrereqs() {}
84 void AsanCheckIncompatibleRT() {}
86 static int FindFirstDSOCallback(struct dl_phdr_info
*info
, size_t size
,
88 // Continue until the first dynamic library is found
89 if (!info
->dlpi_name
|| info
->dlpi_name
[0] == 0)
93 if (internal_strncmp(info
->dlpi_name
, "linux-", sizeof("linux-") - 1) == 0)
96 *(const char **)data
= info
->dlpi_name
;
100 static bool IsDynamicRTName(const char *libname
) {
101 return internal_strstr(libname
, "libclang_rt.asan") ||
102 internal_strstr(libname
, "libasan.so");
105 static void ReportIncompatibleRT() {
106 Report("Your application is linked against incompatible ASan runtimes.\n");
110 void AsanCheckDynamicRTPrereqs() {
114 // Ensure that dynamic RT is the first DSO in the list
115 const char *first_dso_name
= nullptr;
116 dl_iterate_phdr(FindFirstDSOCallback
, &first_dso_name
);
117 if (first_dso_name
&& !IsDynamicRTName(first_dso_name
)) {
118 Report("ASan runtime does not come first in initial library list; "
119 "you should either link runtime to your application or "
120 "manually preload it with LD_PRELOAD.\n");
125 void AsanCheckIncompatibleRT() {
127 if (__asan_rt_version
== ASAN_RT_VERSION_UNDEFINED
) {
128 __asan_rt_version
= ASAN_RT_VERSION_DYNAMIC
;
129 } else if (__asan_rt_version
!= ASAN_RT_VERSION_DYNAMIC
) {
130 ReportIncompatibleRT();
133 if (__asan_rt_version
== ASAN_RT_VERSION_UNDEFINED
) {
134 // Ensure that dynamic runtime is not present. We should detect it
135 // as early as possible, otherwise ASan interceptors could bind to
136 // the functions in dynamic ASan runtime instead of the functions in
137 // system libraries, causing crashes later in ASan initialization.
138 MemoryMappingLayout
proc_maps(/*cache_enabled*/true);
140 while (proc_maps
.Next(nullptr, nullptr, nullptr, filename
,
141 sizeof(filename
), nullptr)) {
142 if (IsDynamicRTName(filename
)) {
143 Report("Your application is linked against "
144 "incompatible ASan runtimes.\n");
148 __asan_rt_version
= ASAN_RT_VERSION_STATIC
;
149 } else if (__asan_rt_version
!= ASAN_RT_VERSION_STATIC
) {
150 ReportIncompatibleRT();
154 #endif // SANITIZER_ANDROID
156 #if !SANITIZER_ANDROID
157 void ReadContextStack(void *context
, uptr
*stack
, uptr
*ssize
) {
158 ucontext_t
*ucp
= (ucontext_t
*)context
;
159 *stack
= (uptr
)ucp
->uc_stack
.ss_sp
;
160 *ssize
= ucp
->uc_stack
.ss_size
;
163 void ReadContextStack(void *context
, uptr
*stack
, uptr
*ssize
) {
168 void *AsanDlSymNext(const char *sym
) {
169 return dlsym(RTLD_NEXT
, sym
);
172 } // namespace __asan
174 #endif // SANITIZER_FREEBSD || SANITIZER_LINUX