From: Kostya Serebryany Date: Fri, 15 Feb 2013 12:00:24 +0000 (+0000) Subject: [asan] make asan work with 7fff8000 offset and prelink X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fd61b6f0c811a831c7b3fdbde4186b3975bbfef2;p=platform%2Fupstream%2Fllvm.git [asan] make asan work with 7fff8000 offset and prelink When prelink is installed in the system, prelink-ed libraries map between 0x003000000000 and 0x004000000000 thus occupying the shadow Gap, so we need so split the address space even further, like this: || [0x10007fff8000, 0x7fffffffffff] || HighMem || || [0x02008fff7000, 0x10007fff7fff] || HighShadow || || [0x004000000000, 0x02008fff6fff] || ShadowGap3 || || [0x003000000000, 0x003fffffffff] || MidMem || || [0x00087fff8000, 0x002fffffffff] || ShadowGap2 || || [0x00067fff8000, 0x00087fff7fff] || MidShadow || || [0x00008fff7000, 0x00067fff7fff] || ShadowGap || || [0x00007fff8000, 0x00008fff6fff] || LowShadow || || [0x000000000000, 0x00007fff7fff] || LowMem || Do it only if necessary. Also added a bit of profiling code to make sure that the mapping code is efficient. Added a lit test to simulate prelink-ed libraries. Unfortunately, this test does not work with binutils-gold linker. If gold is the default linker the test silently passes. Also replaced __has_feature(address_sanitizer) with __has_feature(address_sanitizer) || defined(__SANITIZE_ADDRESS__) in two places. Patch partially by Jakub Jelinek. llvm-svn: 175263 --- diff --git a/compiler-rt/include/sanitizer/asan_interface.h b/compiler-rt/include/sanitizer/asan_interface.h index 04794a4..8adf3f1 100644 --- a/compiler-rt/include/sanitizer/asan_interface.h +++ b/compiler-rt/include/sanitizer/asan_interface.h @@ -37,8 +37,8 @@ extern "C" { // (un)poison memory in the same memory region simultaneously. void __asan_unpoison_memory_region(void const volatile *addr, size_t size); - // User code should use macro instead of functions. -#if __has_feature(address_sanitizer) +// User code should use macros instead of functions. +#if __has_feature(address_sanitizer) || defined(__SANITIZE_ADDRESS__) #define ASAN_POISON_MEMORY_REGION(addr, size) \ __asan_poison_memory_region((addr), (size)) #define ASAN_UNPOISON_MEMORY_REGION(addr, size) \ diff --git a/compiler-rt/include/sanitizer/common_interface_defs.h b/compiler-rt/include/sanitizer/common_interface_defs.h index 238c30d..74e3b22 100644 --- a/compiler-rt/include/sanitizer/common_interface_defs.h +++ b/compiler-rt/include/sanitizer/common_interface_defs.h @@ -16,6 +16,11 @@ #include #include +// GCC does not understand __has_feature. +#if !defined(__has_feature) +# define __has_feature(x) 0 +#endif + #ifdef __cplusplus extern "C" { #endif diff --git a/compiler-rt/lib/asan/asan_internal.h b/compiler-rt/lib/asan/asan_internal.h index dfab3f0..b3b1fe7 100644 --- a/compiler-rt/lib/asan/asan_internal.h +++ b/compiler-rt/lib/asan/asan_internal.h @@ -54,7 +54,7 @@ #define ASAN_POSIX (ASAN_LINUX || ASAN_MAC) -#if __has_feature(address_sanitizer) +#if __has_feature(address_sanitizer) || defined(__SANITIZE_ADDRESS__) # error "The AddressSanitizer run-time should not be" " instrumented by AddressSanitizer" #endif diff --git a/compiler-rt/lib/asan/asan_mapping.h b/compiler-rt/lib/asan/asan_mapping.h index 3e7fc6b..12035e3 100644 --- a/compiler-rt/lib/asan/asan_mapping.h +++ b/compiler-rt/lib/asan/asan_mapping.h @@ -18,6 +18,37 @@ // The full explanation of the memory mapping could be found here: // http://code.google.com/p/address-sanitizer/wiki/AddressSanitizerAlgorithm +// +// Typical shadow mapping on Linux/x86_64 with SHADOW_OFFSET == 0x00007fff8000: +// || `[0x10007fff8000, 0x7fffffffffff]` || HighMem || +// || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow || +// || `[0x00008fff7000, 0x02008fff6fff]` || ShadowGap || +// || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow || +// || `[0x000000000000, 0x00007fff7fff]` || LowMem || +// +// When SHADOW_OFFSET is zero (-pie): +// || `[0x100000000000, 0x7fffffffffff]` || HighMem || +// || `[0x020000000000, 0x0fffffffffff]` || HighShadow || +// || `[0x000000040000, 0x01ffffffffff]` || ShadowGap || +// +// Special case when something is already mapped between +// 0x003000000000 and 0x004000000000 (e.g. when prelink is installed): +// || `[0x10007fff8000, 0x7fffffffffff]` || HighMem || +// || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow || +// || `[0x004000000000, 0x02008fff6fff]` || ShadowGap3 || +// || `[0x003000000000, 0x003fffffffff]` || MidMem || +// || `[0x00087fff8000, 0x002fffffffff]` || ShadowGap2 || +// || `[0x00067fff8000, 0x00087fff7fff]` || MidShadow || +// || `[0x00008fff7000, 0x00067fff7fff]` || ShadowGap || +// || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow || +// || `[0x000000000000, 0x00007fff7fff]` || LowMem || +// +// Default Linux/i386 mapping: +// || `[0x40000000, 0xffffffff]` || HighMem || +// || `[0x28000000, 0x3fffffff]` || HighShadow || +// || `[0x24000000, 0x27ffffff]` || ShadowGap || +// || `[0x20000000, 0x23ffffff]` || LowShadow || +// || `[0x00000000, 0x1fffffff]` || LowMem || #if ASAN_FLEXIBLE_MAPPING_AND_OFFSET == 1 extern SANITIZER_INTERFACE_ATTRIBUTE uptr __asan_mapping_scale; @@ -61,49 +92,105 @@ extern SANITIZER_INTERFACE_ATTRIBUTE uptr __asan_mapping_offset; #define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg) #define kHighShadowEnd MEM_TO_SHADOW(kHighMemEnd) +# define kMidShadowBeg MEM_TO_SHADOW(kMidMemBeg) +# define kMidShadowEnd MEM_TO_SHADOW(kMidMemEnd) + // With the zero shadow base we can not actually map pages starting from 0. // This constant is somewhat arbitrary. #define kZeroBaseShadowStart (1 << 18) #define kShadowGapBeg (kLowShadowEnd ? kLowShadowEnd + 1 \ : kZeroBaseShadowStart) -#define kShadowGapEnd (kHighShadowBeg - 1) +#define kShadowGapEnd ((kMidMemBeg ? kMidShadowBeg : kHighShadowBeg) - 1) + +#define kShadowGap2Beg (kMidMemBeg ? kMidShadowEnd + 1 : 0) +#define kShadowGap2End (kMidMemBeg ? kMidMemBeg - 1 : 0) + +#define kShadowGap3Beg (kMidMemBeg ? kMidMemEnd + 1 : 0) +#define kShadowGap3End (kMidMemBeg ? kHighShadowBeg - 1 : 0) + +#define DO_ASAN_MAPPING_PROFILE 0 // Set to 1 to profile the functions below. + +#if DO_ASAN_MAPPING_PROFILE +# define PROFILE_ASAN_MAPPING() AsanMappingProfile[__LINE__]++; +#else +# define PROFILE_ASAN_MAPPING() +#endif + +// If 1, all shadow boundaries are constants. +// Don't set to 1 other than for testing. +#define ASAN_FIXED_MAPPING 0 namespace __asan { +extern uptr AsanMappingProfile[]; + +#if ASAN_FIXED_MAPPING +// Fixed mapping for 64-bit Linux. Mostly used for performance comparison +// with non-fixed mapping. As of r175253 (Feb 2013) the performance +// difference between fixed and non-fixed mapping is below the noise level. +static uptr kHighMemEnd = 0x7fffffffffffULL; +static uptr kMidMemBeg = 0x3000000000ULL; +static uptr kMidMemEnd = 0x3fffffffffULL; +#else SANITIZER_INTERFACE_ATTRIBUTE -extern uptr kHighMemEnd; // Initialized in __asan_init. +extern uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; // Initialized in __asan_init. +#endif static inline bool AddrIsInLowMem(uptr a) { + PROFILE_ASAN_MAPPING(); return a < kLowMemEnd; } static inline bool AddrIsInLowShadow(uptr a) { + PROFILE_ASAN_MAPPING(); return a >= kLowShadowBeg && a <= kLowShadowEnd; } static inline bool AddrIsInHighMem(uptr a) { + PROFILE_ASAN_MAPPING(); return a >= kHighMemBeg && a <= kHighMemEnd; } +static inline bool AddrIsInMidMem(uptr a) { + PROFILE_ASAN_MAPPING(); + return kMidMemBeg && a >= kMidMemBeg && a <= kMidMemEnd; +} + static inline bool AddrIsInMem(uptr a) { - return AddrIsInLowMem(a) || AddrIsInHighMem(a); + PROFILE_ASAN_MAPPING(); + return AddrIsInLowMem(a) || AddrIsInMidMem(a) || AddrIsInHighMem(a); } static inline uptr MemToShadow(uptr p) { + PROFILE_ASAN_MAPPING(); CHECK(AddrIsInMem(p)); return MEM_TO_SHADOW(p); } static inline bool AddrIsInHighShadow(uptr a) { - return a >= kHighShadowBeg && a <= kHighMemEnd; + PROFILE_ASAN_MAPPING(); + return a >= kHighShadowBeg && a <= kHighMemEnd; +} + +static inline bool AddrIsInMidShadow(uptr a) { + PROFILE_ASAN_MAPPING(); + return kMidMemBeg && a >= kMidShadowBeg && a <= kMidMemEnd; } static inline bool AddrIsInShadow(uptr a) { - return AddrIsInLowShadow(a) || AddrIsInHighShadow(a); + PROFILE_ASAN_MAPPING(); + return AddrIsInLowShadow(a) || AddrIsInMidShadow(a) || AddrIsInHighShadow(a); } static inline bool AddrIsInShadowGap(uptr a) { + PROFILE_ASAN_MAPPING(); + if (kMidMemBeg) { + if (a <= kShadowGapEnd) + return SHADOW_OFFSET == 0 || a >= kShadowGapBeg; + return (a >= kShadowGap2Beg && a <= kShadowGap2End) || + (a >= kShadowGap3Beg && a <= kShadowGap3End); + } // In zero-based shadow mode we treat addresses near zero as addresses // in shadow gap as well. if (SHADOW_OFFSET == 0) @@ -112,10 +199,12 @@ static inline bool AddrIsInShadowGap(uptr a) { } static inline bool AddrIsAlignedByGranularity(uptr a) { + PROFILE_ASAN_MAPPING(); return (a & (SHADOW_GRANULARITY - 1)) == 0; } static inline bool AddressIsPoisoned(uptr a) { + PROFILE_ASAN_MAPPING(); const uptr kAccessSize = 1; u8 *shadow_address = (u8*)MemToShadow(a); s8 shadow_value = *shadow_address; @@ -127,6 +216,9 @@ static inline bool AddressIsPoisoned(uptr a) { return false; } +// Must be after all calls to PROFILE_ASAN_MAPPING(). +static const uptr kAsanMappingProfileSize = __LINE__; + } // namespace __asan #endif // ASAN_MAPPING_H diff --git a/compiler-rt/lib/asan/asan_rtl.cc b/compiler-rt/lib/asan/asan_rtl.cc index 292a36b..6d91e6d 100644 --- a/compiler-rt/lib/asan/asan_rtl.cc +++ b/compiler-rt/lib/asan/asan_rtl.cc @@ -27,6 +27,8 @@ namespace __asan { +uptr AsanMappingProfile[kAsanMappingProfileSize]; + static void AsanDie() { static atomic_uint32_t num_calls; if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) { @@ -37,8 +39,14 @@ static void AsanDie() { Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying); SleepForSeconds(flags()->sleep_before_dying); } - if (flags()->unmap_shadow_on_exit) - UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg); + if (flags()->unmap_shadow_on_exit) { + if (kMidMemBeg) { + UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg); + UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd); + } else { + UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg); + } + } if (death_callback) death_callback(); if (flags()->abort_on_error) @@ -163,7 +171,10 @@ void InitializeFlags(Flags *f, const char *env) { int asan_inited; bool asan_init_is_running; void (*death_callback)(void); -uptr kHighMemEnd; + +#if !ASAN_FIXED_MAPPING +uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; +#endif // -------------------------- Misc ---------------- {{{1 void ShowStatsAndAbort() { @@ -261,9 +272,15 @@ static NOINLINE void force_interface_symbols() { static void asan_atexit() { Printf("AddressSanitizer exit stats:\n"); __asan_print_accumulated_stats(); + // Print AsanMappingProfile. + for (uptr i = 0; i < kAsanMappingProfileSize; i++) { + if (AsanMappingProfile[i] == 0) continue; + Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]); + } } static void InitializeHighMemEnd() { +#if !ASAN_FIXED_MAPPING #if SANITIZER_WORDSIZE == 64 # if defined(__powerpc64__) // FIXME: @@ -279,6 +296,58 @@ static void InitializeHighMemEnd() { #else // SANITIZER_WORDSIZE == 32 kHighMemEnd = (1ULL << 32) - 1; // 0xffffffff; #endif // SANITIZER_WORDSIZE +#endif // !ASAN_FIXED_MAPPING +} + +static void ProtectGap(uptr a, uptr size) { + CHECK_EQ(a, (uptr)Mprotect(a, size)); +} + +static void PrintAddressSpaceLayout() { + Printf("|| `[%p, %p]` || HighMem ||\n", + (void*)kHighMemBeg, (void*)kHighMemEnd); + Printf("|| `[%p, %p]` || HighShadow ||\n", + (void*)kHighShadowBeg, (void*)kHighShadowEnd); + if (kMidMemBeg) { + Printf("|| `[%p, %p]` || ShadowGap3 ||\n", + (void*)kShadowGap3Beg, (void*)kShadowGap3End); + Printf("|| `[%p, %p]` || MidMem ||\n", + (void*)kMidMemBeg, (void*)kMidMemEnd); + Printf("|| `[%p, %p]` || ShadowGap2 ||\n", + (void*)kShadowGap2Beg, (void*)kShadowGap2End); + Printf("|| `[%p, %p]` || MidShadow ||\n", + (void*)kMidShadowBeg, (void*)kMidShadowEnd); + } + Printf("|| `[%p, %p]` || ShadowGap ||\n", + (void*)kShadowGapBeg, (void*)kShadowGapEnd); + if (kLowShadowBeg) { + Printf("|| `[%p, %p]` || LowShadow ||\n", + (void*)kLowShadowBeg, (void*)kLowShadowEnd); + Printf("|| `[%p, %p]` || LowMem ||\n", + (void*)kLowMemBeg, (void*)kLowMemEnd); + } + Printf("MemToShadow(shadow): %p %p %p %p", + (void*)MEM_TO_SHADOW(kLowShadowBeg), + (void*)MEM_TO_SHADOW(kLowShadowEnd), + (void*)MEM_TO_SHADOW(kHighShadowBeg), + (void*)MEM_TO_SHADOW(kHighShadowEnd)); + if (kMidMemBeg) { + Printf(" %p %p", + (void*)MEM_TO_SHADOW(kMidShadowBeg), + (void*)MEM_TO_SHADOW(kMidShadowEnd)); + } + Printf("\n"); + Printf("red_zone=%zu\n", (uptr)flags()->redzone); + Printf("malloc_context_size=%zu\n", (uptr)flags()->malloc_context_size); + + Printf("SHADOW_SCALE: %zx\n", (uptr)SHADOW_SCALE); + Printf("SHADOW_GRANULARITY: %zx\n", (uptr)SHADOW_GRANULARITY); + Printf("SHADOW_OFFSET: %zx\n", (uptr)SHADOW_OFFSET); + CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7); + if (kMidMemBeg) + CHECK(kMidShadowBeg > kLowShadowEnd && + kMidMemBeg > kMidShadowEnd && + kHighShadowBeg > kMidMemEnd); } } // namespace __asan @@ -354,49 +423,48 @@ void __asan_init() { ReplaceSystemMalloc(); ReplaceOperatorsNewAndDelete(); - if (flags()->verbosity) { - Printf("|| `[%p, %p]` || HighMem ||\n", - (void*)kHighMemBeg, (void*)kHighMemEnd); - Printf("|| `[%p, %p]` || HighShadow ||\n", - (void*)kHighShadowBeg, (void*)kHighShadowEnd); - Printf("|| `[%p, %p]` || ShadowGap ||\n", - (void*)kShadowGapBeg, (void*)kShadowGapEnd); - Printf("|| `[%p, %p]` || LowShadow ||\n", - (void*)kLowShadowBeg, (void*)kLowShadowEnd); - Printf("|| `[%p, %p]` || LowMem ||\n", - (void*)kLowMemBeg, (void*)kLowMemEnd); - Printf("MemToShadow(shadow): %p %p %p %p\n", - (void*)MEM_TO_SHADOW(kLowShadowBeg), - (void*)MEM_TO_SHADOW(kLowShadowEnd), - (void*)MEM_TO_SHADOW(kHighShadowBeg), - (void*)MEM_TO_SHADOW(kHighShadowEnd)); - Printf("red_zone=%zu\n", (uptr)flags()->redzone); - Printf("malloc_context_size=%zu\n", (uptr)flags()->malloc_context_size); - - Printf("SHADOW_SCALE: %zx\n", (uptr)SHADOW_SCALE); - Printf("SHADOW_GRANULARITY: %zx\n", (uptr)SHADOW_GRANULARITY); - Printf("SHADOW_OFFSET: %zx\n", (uptr)SHADOW_OFFSET); - CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7); + uptr shadow_start = kLowShadowBeg; + if (kLowShadowBeg) shadow_start -= GetMmapGranularity(); + uptr shadow_end = kHighShadowEnd; + bool full_shadow_is_available = + MemoryRangeIsAvailable(shadow_start, shadow_end); + +#if ASAN_LINUX && defined(__x86_64__) && !ASAN_FIXED_MAPPING + if (!full_shadow_is_available) { + kMidMemBeg = kLowMemEnd < 0x3000000000ULL ? 0x3000000000ULL : 0; + kMidMemEnd = kLowMemEnd < 0x3000000000ULL ? 0x3fffffffffULL : 0; } +#endif + + if (flags()->verbosity) + PrintAddressSpaceLayout(); if (flags()->disable_core) { DisableCoreDumper(); } - uptr shadow_start = kLowShadowBeg; - if (kLowShadowBeg > 0) shadow_start -= GetMmapGranularity(); - uptr shadow_end = kHighShadowEnd; - if (MemoryRangeIsAvailable(shadow_start, shadow_end)) { - if (kLowShadowBeg != kLowShadowEnd) { - // mmap the low shadow plus at least one page. - ReserveShadowMemoryRange(kLowShadowBeg - GetMmapGranularity(), - kLowShadowEnd); - } + if (full_shadow_is_available) { + // mmap the low shadow plus at least one page at the left. + if (kLowShadowBeg) + ReserveShadowMemoryRange(shadow_start, kLowShadowEnd); + // mmap the high shadow. + ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd); + // protect the gap. + ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1); + } else if (kMidMemBeg && + MemoryRangeIsAvailable(shadow_start, kMidMemBeg - 1) && + MemoryRangeIsAvailable(kMidMemEnd + 1, shadow_end)) { + CHECK(kLowShadowBeg != kLowShadowEnd); + // mmap the low shadow plus at least one page at the left. + ReserveShadowMemoryRange(shadow_start, kLowShadowEnd); + // mmap the mid shadow. + ReserveShadowMemoryRange(kMidShadowBeg, kMidShadowEnd); // mmap the high shadow. ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd); - // protect the gap - void *prot = Mprotect(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1); - CHECK(prot == (void*)kShadowGapBeg); + // protect the gaps. + ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1); + ProtectGap(kShadowGap2Beg, kShadowGap2End - kShadowGap2Beg + 1); + ProtectGap(kShadowGap3Beg, kShadowGap3End - kShadowGap3Beg + 1); } else { Report("Shadow memory range interleaves with an existing memory mapping. " "ASan cannot proceed correctly. ABORTING.\n"); diff --git a/compiler-rt/lib/asan/lit_tests/Linux/asan_prelink_test.cc b/compiler-rt/lib/asan/lit_tests/Linux/asan_prelink_test.cc new file mode 100644 index 0000000..de329fb --- /dev/null +++ b/compiler-rt/lib/asan/lit_tests/Linux/asan_prelink_test.cc @@ -0,0 +1,25 @@ +// Test if asan works with prelink. +// It does not actually use prelink, but relies on ld's flag -Ttext-segment. +// This flag is not present in GNU gold, so if the link command line fails +// we just exit 0. +// +// RUN: %clangxx_asan -m64 -c %s -o %t.o +// RUN: %clangxx_asan -m64 -DBUILD_SO=1 -fPIC -shared %s -o %t.so -Wl,-Ttext-segment=0x3600000000 || exit 0 +// RUN: %clangxx_asan -m64 %t.o %t.so -Wl,-R. -o %t +// RUN: ASAN_OPTIONS=verbosity=1 %t 2>&1 | FileCheck %s +#if BUILD_SO +int G; +int *getG() { + return &G; +} +#else +#include +extern int *getG(); +int main(int argc, char **argv) { + long p = (long)getG(); + printf("SO mapped at %lx\n", p & ~0xffffffffUL); + *getG() = 0; +} +#endif +// CHECK: 0x003000000000, 0x003fffffffff{{.*}} MidMem +// CHECK: SO mapped at 3600000000 diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h b/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h index af53395..083761b 100644 --- a/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h +++ b/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h @@ -31,7 +31,7 @@ # define SANITIZER_SUPPORTS_WEAK_HOOKS 0 #endif -// __has_feature +// GCC does not understand __has_feature #if !defined(__has_feature) # define __has_feature(x) 0 #endif