diff options
Diffstat (limited to 'lib/sanitizer_common/sanitizer_linux_libcdep.cc')
| -rw-r--r-- | lib/sanitizer_common/sanitizer_linux_libcdep.cc | 295 |
1 files changed, 184 insertions, 111 deletions
diff --git a/lib/sanitizer_common/sanitizer_linux_libcdep.cc b/lib/sanitizer_common/sanitizer_linux_libcdep.cc index 2940686f1275..4e09081e7f54 100644 --- a/lib/sanitizer_common/sanitizer_linux_libcdep.cc +++ b/lib/sanitizer_common/sanitizer_linux_libcdep.cc @@ -13,31 +13,68 @@ //===----------------------------------------------------------------------===// #include "sanitizer_platform.h" -#if SANITIZER_LINUX +#if SANITIZER_FREEBSD || SANITIZER_LINUX #include "sanitizer_common.h" #include "sanitizer_flags.h" +#include "sanitizer_freebsd.h" #include "sanitizer_linux.h" #include "sanitizer_placement_new.h" #include "sanitizer_procmaps.h" #include "sanitizer_stacktrace.h" +#include "sanitizer_atomic.h" +#include "sanitizer_symbolizer.h" + +#if SANITIZER_ANDROID || SANITIZER_FREEBSD +#include <dlfcn.h> // for dlsym() +#endif -#include <dlfcn.h> #include <pthread.h> -#include <sys/prctl.h> +#include <signal.h> #include <sys/resource.h> -#include <unwind.h> + +#if SANITIZER_FREEBSD +#include <pthread_np.h> +#include <osreldate.h> +#define pthread_getattr_np pthread_attr_get_np +#endif + +#if SANITIZER_LINUX +#include <sys/prctl.h> +#endif #if !SANITIZER_ANDROID #include <elf.h> #include <link.h> +#include <unistd.h> #endif namespace __sanitizer { +// This function is defined elsewhere if we intercepted pthread_attr_getstack. +extern "C" { +SANITIZER_WEAK_ATTRIBUTE int +real_pthread_attr_getstack(void *attr, void **addr, size_t *size); +} // extern "C" + +static int my_pthread_attr_getstack(void *attr, void **addr, size_t *size) { + if (real_pthread_attr_getstack) + return real_pthread_attr_getstack((pthread_attr_t *)attr, addr, size); + return pthread_attr_getstack((pthread_attr_t *)attr, addr, size); +} + +SANITIZER_WEAK_ATTRIBUTE int +real_sigaction(int signum, const void *act, void *oldact); + +int internal_sigaction(int signum, const void *act, void *oldact) { + if (real_sigaction) + return real_sigaction(signum, act, oldact); + return sigaction(signum, (const struct sigaction *)act, + (struct sigaction *)oldact); +} + void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top, uptr *stack_bottom) { - static const uptr kMaxThreadStackSize = 1 << 30; // 1Gb CHECK(stack_top); CHECK(stack_bottom); if (at_initialization) { @@ -71,10 +108,11 @@ void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top, return; } pthread_attr_t attr; + pthread_attr_init(&attr); CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0); uptr stacksize = 0; void *stackaddr = 0; - pthread_attr_getstack(&attr, &stackaddr, (size_t*)&stacksize); + my_pthread_attr_getstack(&attr, &stackaddr, (size_t*)&stacksize); pthread_attr_destroy(&attr); CHECK_LE(stacksize, kMaxThreadStackSize); // Sanity check. @@ -82,8 +120,6 @@ void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top, *stack_bottom = (uptr)stackaddr; } -// Does not compile for Go because dlsym() requires -ldl -#ifndef SANITIZER_GO bool SetEnv(const char *name, const char *value) { void *f = dlsym(RTLD_NEXT, "setenv"); if (f == 0) @@ -94,7 +130,6 @@ bool SetEnv(const char *name, const char *value) { internal_memcpy(&setenv_f, &f, sizeof(f)); return setenv_f(name, value, 1) == 0; } -#endif bool SanitizerSetThreadName(const char *name) { #ifdef PR_SET_NAME @@ -117,61 +152,9 @@ bool SanitizerGetThreadName(char *name, int max_len) { #endif } -#ifndef SANITIZER_GO -//------------------------- SlowUnwindStack ----------------------------------- -#ifdef __arm__ -#define UNWIND_STOP _URC_END_OF_STACK -#define UNWIND_CONTINUE _URC_NO_REASON -#else -#define UNWIND_STOP _URC_NORMAL_STOP -#define UNWIND_CONTINUE _URC_NO_REASON -#endif - -uptr Unwind_GetIP(struct _Unwind_Context *ctx) { -#ifdef __arm__ - uptr val; - _Unwind_VRS_Result res = _Unwind_VRS_Get(ctx, _UVRSC_CORE, - 15 /* r15 = PC */, _UVRSD_UINT32, &val); - CHECK(res == _UVRSR_OK && "_Unwind_VRS_Get failed"); - // Clear the Thumb bit. - return val & ~(uptr)1; -#else - return _Unwind_GetIP(ctx); -#endif -} - -struct UnwindTraceArg { - StackTrace *stack; - uptr max_depth; -}; - -_Unwind_Reason_Code Unwind_Trace(struct _Unwind_Context *ctx, void *param) { - UnwindTraceArg *arg = (UnwindTraceArg*)param; - CHECK_LT(arg->stack->size, arg->max_depth); - uptr pc = Unwind_GetIP(ctx); - arg->stack->trace[arg->stack->size++] = pc; - if (arg->stack->size == arg->max_depth) return UNWIND_STOP; - return UNWIND_CONTINUE; -} - -void StackTrace::SlowUnwindStack(uptr pc, uptr max_depth) { - size = 0; - if (max_depth == 0) - return; - UnwindTraceArg arg = {this, Min(max_depth + 1, kStackTraceMax)}; - _Unwind_Backtrace(Unwind_Trace, &arg); - // We need to pop a few frames so that pc is on top. - uptr to_pop = LocatePcInTrace(pc); - // trace[0] belongs to the current function so we always pop it. - if (to_pop == 0) - to_pop = 1; - PopStackFrames(to_pop); - trace[0] = pc; -} - -#endif // !SANITIZER_GO - +#if !SANITIZER_FREEBSD static uptr g_tls_size; +#endif #ifdef __i386__ # define DL_INTERNAL_FUNCTION __attribute__((regparm(3), stdcall)) @@ -180,7 +163,7 @@ static uptr g_tls_size; #endif void InitTlsSize() { -#if !defined(SANITIZER_GO) && !SANITIZER_ANDROID +#if !SANITIZER_FREEBSD && !SANITIZER_ANDROID typedef void (*get_tls_func)(size_t*, size_t*) DL_INTERNAL_FUNCTION; get_tls_func get_tls; void *get_tls_static_info_ptr = dlsym(RTLD_NEXT, "_dl_get_tls_static_info"); @@ -192,25 +175,48 @@ void InitTlsSize() { size_t tls_align = 0; get_tls(&tls_size, &tls_align); g_tls_size = tls_size; -#endif +#endif // !SANITIZER_FREEBSD && !SANITIZER_ANDROID } -uptr GetTlsSize() { - return g_tls_size; -} - -#if defined(__x86_64__) || defined(__i386__) +#if (defined(__x86_64__) || defined(__i386__)) && SANITIZER_LINUX // sizeof(struct thread) from glibc. -// There has been a report of this being different on glibc 2.11 and 2.13. We -// don't know when this change happened, so 2.14 is a conservative estimate. -#if __GLIBC_PREREQ(2, 14) -const uptr kThreadDescriptorSize = FIRST_32_SECOND_64(1216, 2304); -#else -const uptr kThreadDescriptorSize = FIRST_32_SECOND_64(1168, 2304); -#endif +static atomic_uintptr_t kThreadDescriptorSize; uptr ThreadDescriptorSize() { - return kThreadDescriptorSize; + uptr val = atomic_load(&kThreadDescriptorSize, memory_order_relaxed); + if (val) + return val; +#ifdef _CS_GNU_LIBC_VERSION + char buf[64]; + uptr len = confstr(_CS_GNU_LIBC_VERSION, buf, sizeof(buf)); + if (len < sizeof(buf) && internal_strncmp(buf, "glibc 2.", 8) == 0) { + char *end; + int minor = internal_simple_strtoll(buf + 8, &end, 10); + if (end != buf + 8 && (*end == '\0' || *end == '.')) { + /* sizeof(struct thread) values from various glibc versions. */ + if (SANITIZER_X32) + val = 1728; // Assume only one particular version for x32. + else if (minor <= 3) + val = FIRST_32_SECOND_64(1104, 1696); + else if (minor == 4) + val = FIRST_32_SECOND_64(1120, 1728); + else if (minor == 5) + val = FIRST_32_SECOND_64(1136, 1728); + else if (minor <= 9) + val = FIRST_32_SECOND_64(1136, 1712); + else if (minor == 10) + val = FIRST_32_SECOND_64(1168, 1776); + else if (minor <= 12) + val = FIRST_32_SECOND_64(1168, 2288); + else + val = FIRST_32_SECOND_64(1216, 2304); + } + if (val) + atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed); + return val; + } +#endif + return 0; } // The offset at which pointer to self is located in the thread descriptor. @@ -222,27 +228,79 @@ uptr ThreadSelfOffset() { uptr ThreadSelf() { uptr descr_addr; -#ifdef __i386__ +# if defined(__i386__) asm("mov %%gs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset)); -#else +# elif defined(__x86_64__) asm("mov %%fs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset)); -#endif +# else +# error "unsupported CPU arch" +# endif return descr_addr; } -#endif // defined(__x86_64__) || defined(__i386__) +#endif // (defined(__x86_64__) || defined(__i386__)) && SANITIZER_LINUX + +#if SANITIZER_FREEBSD +static void **ThreadSelfSegbase() { + void **segbase = 0; +# if defined(__i386__) + // sysarch(I386_GET_GSBASE, segbase); + __asm __volatile("mov %%gs:0, %0" : "=r" (segbase)); +# elif defined(__x86_64__) + // sysarch(AMD64_GET_FSBASE, segbase); + __asm __volatile("movq %%fs:0, %0" : "=r" (segbase)); +# else +# error "unsupported CPU arch for FreeBSD platform" +# endif + return segbase; +} -void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size, - uptr *tls_addr, uptr *tls_size) { -#ifndef SANITIZER_GO -#if defined(__x86_64__) || defined(__i386__) - *tls_addr = ThreadSelf(); - *tls_size = GetTlsSize(); - *tls_addr -= *tls_size; - *tls_addr += kThreadDescriptorSize; +uptr ThreadSelf() { + return (uptr)ThreadSelfSegbase()[2]; +} +#endif // SANITIZER_FREEBSD + +static void GetTls(uptr *addr, uptr *size) { +#if SANITIZER_LINUX +# if defined(__x86_64__) || defined(__i386__) + *addr = ThreadSelf(); + *size = GetTlsSize(); + *addr -= *size; + *addr += ThreadDescriptorSize(); +# else + *addr = 0; + *size = 0; +# endif +#elif SANITIZER_FREEBSD + void** segbase = ThreadSelfSegbase(); + *addr = 0; + *size = 0; + if (segbase != 0) { + // tcbalign = 16 + // tls_size = round(tls_static_space, tcbalign); + // dtv = segbase[1]; + // dtv[2] = segbase - tls_static_space; + void **dtv = (void**) segbase[1]; + *addr = (uptr) dtv[2]; + *size = (*addr == 0) ? 0 : ((uptr) segbase[0] - (uptr) dtv[2]); + } #else - *tls_addr = 0; - *tls_size = 0; +# error "Unknown OS" #endif +} + +uptr GetTlsSize() { +#if SANITIZER_FREEBSD + uptr addr, size; + GetTls(&addr, &size); + return size; +#else + return g_tls_size; +#endif +} + +void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size, + uptr *tls_addr, uptr *tls_size) { + GetTls(tls_addr, tls_size); uptr stack_top, stack_bottom; GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom); @@ -258,19 +316,13 @@ void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size, *tls_addr = *stk_addr + *stk_size; } } -#else // SANITIZER_GO - *stk_addr = 0; - *stk_size = 0; - *tls_addr = 0; - *tls_size = 0; -#endif // SANITIZER_GO } -void AdjustStackSizeLinux(void *attr_) { +void AdjustStackSize(void *attr_) { pthread_attr_t *attr = (pthread_attr_t *)attr_; uptr stackaddr = 0; size_t stacksize = 0; - pthread_attr_getstack(attr, (void**)&stackaddr, &stacksize); + my_pthread_attr_getstack(attr, (void**)&stackaddr, &stacksize); // GLibC will return (0 - stacksize) as the stack address in the case when // stacksize is set, but stackaddr is not. bool stack_set = (stackaddr != 0) && (stackaddr + stacksize != 0); @@ -278,10 +330,11 @@ void AdjustStackSizeLinux(void *attr_) { const uptr minstacksize = GetTlsSize() + 128*1024; if (stacksize < minstacksize) { if (!stack_set) { - if (common_flags()->verbosity && stacksize != 0) - Printf("Sanitizer: increasing stacksize %zu->%zu\n", stacksize, - minstacksize); - pthread_attr_setstacksize(attr, minstacksize); + if (stacksize != 0) { + VPrintf(1, "Sanitizer: increasing stacksize %zu->%zu\n", stacksize, + minstacksize); + pthread_attr_setstacksize(attr, minstacksize); + } } else { Printf("Sanitizer: pre-allocated stack size is insufficient: " "%zu < %zu\n", stacksize, minstacksize); @@ -293,10 +346,17 @@ void AdjustStackSizeLinux(void *attr_) { #if SANITIZER_ANDROID uptr GetListOfModules(LoadedModule *modules, uptr max_modules, string_predicate_t filter) { - return 0; + MemoryMappingLayout memory_mapping(false); + return memory_mapping.DumpListOfModules(modules, max_modules, filter); } #else // SANITIZER_ANDROID +# if !SANITIZER_FREEBSD typedef ElfW(Phdr) Elf_Phdr; +# elif SANITIZER_WORDSIZE == 32 && __FreeBSD_version <= 902001 // v9.2 +# define Elf_Phdr XElf32_Phdr +# define dl_phdr_info xdl_phdr_info +# define dl_iterate_phdr(c, b) xdl_iterate_phdr((c), (b)) +# endif struct DlIteratePhdrData { LoadedModule *modules; @@ -310,16 +370,15 @@ static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) { DlIteratePhdrData *data = (DlIteratePhdrData*)arg; if (data->current_n == data->max_n) return 0; - InternalScopedBuffer<char> module_name(kMaxPathLength); - module_name.data()[0] = '\0'; + InternalScopedString module_name(kMaxPathLength); if (data->first) { data->first = false; // First module is the binary itself. ReadBinaryName(module_name.data(), module_name.size()); } else if (info->dlpi_name) { - internal_strncpy(module_name.data(), info->dlpi_name, module_name.size()); + module_name.append("%s", info->dlpi_name); } - if (module_name.data()[0] == '\0') + if (module_name[0] == '\0') return 0; if (data->filter && !data->filter(module_name.data())) return 0; @@ -332,7 +391,8 @@ static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) { if (phdr->p_type == PT_LOAD) { uptr cur_beg = info->dlpi_addr + phdr->p_vaddr; uptr cur_end = cur_beg + phdr->p_memsz; - cur_module->addAddressRange(cur_beg, cur_end); + bool executable = phdr->p_flags & PF_X; + cur_module->addAddressRange(cur_beg, cur_end, executable); } } return 0; @@ -347,6 +407,19 @@ uptr GetListOfModules(LoadedModule *modules, uptr max_modules, } #endif // SANITIZER_ANDROID +void PrepareForSandboxing(__sanitizer_sandbox_arguments *args) { + // Some kinds of sandboxes may forbid filesystem access, so we won't be able + // to read the file mappings from /proc/self/maps. Luckily, neither the + // process will be able to load additional libraries, so it's fine to use the + // cached mappings. + MemoryMappingLayout::CacheMemoryMappings(); + // Same for /proc/self/exe in the symbolizer. +#if !SANITIZER_GO + Symbolizer::GetOrInit()->PrepareForSandboxing(); + CovPrepareForSandboxing(args); +#endif +} + } // namespace __sanitizer -#endif // SANITIZER_LINUX +#endif // SANITIZER_FREEBSD || SANITIZER_LINUX |