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authornkozlovskiy <nmk@ydb.tech>2023-10-11 19:11:46 +0300
committernkozlovskiy <nmk@ydb.tech>2023-10-11 19:33:28 +0300
commit61b3971447e473726d6cdb23fc298e457b4d973c (patch)
treee2a2a864bb7717f7ae6138f6a3194a254dd2c7bb /contrib/libs/clang14-rt/lib/asan/asan_globals.cpp
parenta674dc57d88d43c2e8e90a6084d5d2c988e0402c (diff)
downloadydb-61b3971447e473726d6cdb23fc298e457b4d973c.tar.gz
add sanitizers dependencies
Diffstat (limited to 'contrib/libs/clang14-rt/lib/asan/asan_globals.cpp')
-rw-r--r--contrib/libs/clang14-rt/lib/asan/asan_globals.cpp463
1 files changed, 463 insertions, 0 deletions
diff --git a/contrib/libs/clang14-rt/lib/asan/asan_globals.cpp b/contrib/libs/clang14-rt/lib/asan/asan_globals.cpp
new file mode 100644
index 0000000000..ecc2600f03
--- /dev/null
+++ b/contrib/libs/clang14-rt/lib/asan/asan_globals.cpp
@@ -0,0 +1,463 @@
+//===-- asan_globals.cpp --------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of AddressSanitizer, an address sanity checker.
+//
+// Handle globals.
+//===----------------------------------------------------------------------===//
+
+#include "asan_interceptors.h"
+#include "asan_internal.h"
+#include "asan_mapping.h"
+#include "asan_poisoning.h"
+#include "asan_report.h"
+#include "asan_stack.h"
+#include "asan_stats.h"
+#include "asan_suppressions.h"
+#include "asan_thread.h"
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_mutex.h"
+#include "sanitizer_common/sanitizer_placement_new.h"
+#include "sanitizer_common/sanitizer_stackdepot.h"
+#include "sanitizer_common/sanitizer_symbolizer.h"
+
+namespace __asan {
+
+typedef __asan_global Global;
+
+struct ListOfGlobals {
+ const Global *g;
+ ListOfGlobals *next;
+};
+
+static Mutex mu_for_globals;
+static LowLevelAllocator allocator_for_globals;
+static ListOfGlobals *list_of_all_globals;
+
+static const int kDynamicInitGlobalsInitialCapacity = 512;
+struct DynInitGlobal {
+ Global g;
+ bool initialized;
+};
+typedef InternalMmapVector<DynInitGlobal> VectorOfGlobals;
+// Lazy-initialized and never deleted.
+static VectorOfGlobals *dynamic_init_globals;
+
+// We want to remember where a certain range of globals was registered.
+struct GlobalRegistrationSite {
+ u32 stack_id;
+ Global *g_first, *g_last;
+};
+typedef InternalMmapVector<GlobalRegistrationSite> GlobalRegistrationSiteVector;
+static GlobalRegistrationSiteVector *global_registration_site_vector;
+
+ALWAYS_INLINE void PoisonShadowForGlobal(const Global *g, u8 value) {
+ FastPoisonShadow(g->beg, g->size_with_redzone, value);
+}
+
+ALWAYS_INLINE void PoisonRedZones(const Global &g) {
+ uptr aligned_size = RoundUpTo(g.size, ASAN_SHADOW_GRANULARITY);
+ FastPoisonShadow(g.beg + aligned_size, g.size_with_redzone - aligned_size,
+ kAsanGlobalRedzoneMagic);
+ if (g.size != aligned_size) {
+ FastPoisonShadowPartialRightRedzone(
+ g.beg + RoundDownTo(g.size, ASAN_SHADOW_GRANULARITY),
+ g.size % ASAN_SHADOW_GRANULARITY, ASAN_SHADOW_GRANULARITY,
+ kAsanGlobalRedzoneMagic);
+ }
+}
+
+const uptr kMinimalDistanceFromAnotherGlobal = 64;
+
+static bool IsAddressNearGlobal(uptr addr, const __asan_global &g) {
+ if (addr <= g.beg - kMinimalDistanceFromAnotherGlobal) return false;
+ if (addr >= g.beg + g.size_with_redzone) return false;
+ return true;
+}
+
+static void ReportGlobal(const Global &g, const char *prefix) {
+ Report(
+ "%s Global[%p]: beg=%p size=%zu/%zu name=%s module=%s dyn_init=%zu "
+ "odr_indicator=%p\n",
+ prefix, (void *)&g, (void *)g.beg, g.size, g.size_with_redzone, g.name,
+ g.module_name, g.has_dynamic_init, (void *)g.odr_indicator);
+ if (g.location) {
+ Report(" location (%p): name=%s[%p], %d %d\n", (void *)g.location,
+ g.location->filename, (void *)g.location->filename,
+ g.location->line_no, g.location->column_no);
+ }
+}
+
+static u32 FindRegistrationSite(const Global *g) {
+ mu_for_globals.CheckLocked();
+ CHECK(global_registration_site_vector);
+ for (uptr i = 0, n = global_registration_site_vector->size(); i < n; i++) {
+ GlobalRegistrationSite &grs = (*global_registration_site_vector)[i];
+ if (g >= grs.g_first && g <= grs.g_last)
+ return grs.stack_id;
+ }
+ return 0;
+}
+
+int GetGlobalsForAddress(uptr addr, Global *globals, u32 *reg_sites,
+ int max_globals) {
+ if (!flags()->report_globals) return 0;
+ Lock lock(&mu_for_globals);
+ int res = 0;
+ for (ListOfGlobals *l = list_of_all_globals; l; l = l->next) {
+ const Global &g = *l->g;
+ if (flags()->report_globals >= 2)
+ ReportGlobal(g, "Search");
+ if (IsAddressNearGlobal(addr, g)) {
+ internal_memcpy(&globals[res], &g, sizeof(g));
+ if (reg_sites)
+ reg_sites[res] = FindRegistrationSite(&g);
+ res++;
+ if (res == max_globals)
+ break;
+ }
+ }
+ return res;
+}
+
+enum GlobalSymbolState {
+ UNREGISTERED = 0,
+ REGISTERED = 1
+};
+
+// Check ODR violation for given global G via special ODR indicator. We use
+// this method in case compiler instruments global variables through their
+// local aliases.
+static void CheckODRViolationViaIndicator(const Global *g) {
+ // Instrumentation requests to skip ODR check.
+ if (g->odr_indicator == UINTPTR_MAX)
+ return;
+ u8 *odr_indicator = reinterpret_cast<u8 *>(g->odr_indicator);
+ if (*odr_indicator == UNREGISTERED) {
+ *odr_indicator = REGISTERED;
+ return;
+ }
+ // If *odr_indicator is DEFINED, some module have already registered
+ // externally visible symbol with the same name. This is an ODR violation.
+ for (ListOfGlobals *l = list_of_all_globals; l; l = l->next) {
+ if (g->odr_indicator == l->g->odr_indicator &&
+ (flags()->detect_odr_violation >= 2 || g->size != l->g->size) &&
+ !IsODRViolationSuppressed(g->name))
+ ReportODRViolation(g, FindRegistrationSite(g),
+ l->g, FindRegistrationSite(l->g));
+ }
+}
+
+// Check ODR violation for given global G by checking if it's already poisoned.
+// We use this method in case compiler doesn't use private aliases for global
+// variables.
+static void CheckODRViolationViaPoisoning(const Global *g) {
+ if (__asan_region_is_poisoned(g->beg, g->size_with_redzone)) {
+ // This check may not be enough: if the first global is much larger
+ // the entire redzone of the second global may be within the first global.
+ for (ListOfGlobals *l = list_of_all_globals; l; l = l->next) {
+ if (g->beg == l->g->beg &&
+ (flags()->detect_odr_violation >= 2 || g->size != l->g->size) &&
+ !IsODRViolationSuppressed(g->name))
+ ReportODRViolation(g, FindRegistrationSite(g),
+ l->g, FindRegistrationSite(l->g));
+ }
+ }
+}
+
+// Clang provides two different ways for global variables protection:
+// it can poison the global itself or its private alias. In former
+// case we may poison same symbol multiple times, that can help us to
+// cheaply detect ODR violation: if we try to poison an already poisoned
+// global, we have ODR violation error.
+// In latter case, we poison each symbol exactly once, so we use special
+// indicator symbol to perform similar check.
+// In either case, compiler provides a special odr_indicator field to Global
+// structure, that can contain two kinds of values:
+// 1) Non-zero value. In this case, odr_indicator is an address of
+// corresponding indicator variable for given global.
+// 2) Zero. This means that we don't use private aliases for global variables
+// and can freely check ODR violation with the first method.
+//
+// This routine chooses between two different methods of ODR violation
+// detection.
+static inline bool UseODRIndicator(const Global *g) {
+ return g->odr_indicator > 0;
+}
+
+// Register a global variable.
+// This function may be called more than once for every global
+// so we store the globals in a map.
+static void RegisterGlobal(const Global *g) {
+ CHECK(asan_inited);
+ if (flags()->report_globals >= 2)
+ ReportGlobal(*g, "Added");
+ CHECK(flags()->report_globals);
+ CHECK(AddrIsInMem(g->beg));
+ if (!AddrIsAlignedByGranularity(g->beg)) {
+ Report("The following global variable is not properly aligned.\n");
+ Report("This may happen if another global with the same name\n");
+ Report("resides in another non-instrumented module.\n");
+ Report("Or the global comes from a C file built w/o -fno-common.\n");
+ Report("In either case this is likely an ODR violation bug,\n");
+ Report("but AddressSanitizer can not provide more details.\n");
+ ReportODRViolation(g, FindRegistrationSite(g), g, FindRegistrationSite(g));
+ CHECK(AddrIsAlignedByGranularity(g->beg));
+ }
+ CHECK(AddrIsAlignedByGranularity(g->size_with_redzone));
+ if (flags()->detect_odr_violation) {
+ // Try detecting ODR (One Definition Rule) violation, i.e. the situation
+ // where two globals with the same name are defined in different modules.
+ if (UseODRIndicator(g))
+ CheckODRViolationViaIndicator(g);
+ else
+ CheckODRViolationViaPoisoning(g);
+ }
+ if (CanPoisonMemory())
+ PoisonRedZones(*g);
+ ListOfGlobals *l = new(allocator_for_globals) ListOfGlobals;
+ l->g = g;
+ l->next = list_of_all_globals;
+ list_of_all_globals = l;
+ if (g->has_dynamic_init) {
+ if (!dynamic_init_globals) {
+ dynamic_init_globals = new (allocator_for_globals) VectorOfGlobals;
+ dynamic_init_globals->reserve(kDynamicInitGlobalsInitialCapacity);
+ }
+ DynInitGlobal dyn_global = { *g, false };
+ dynamic_init_globals->push_back(dyn_global);
+ }
+}
+
+static void UnregisterGlobal(const Global *g) {
+ CHECK(asan_inited);
+ if (flags()->report_globals >= 2)
+ ReportGlobal(*g, "Removed");
+ CHECK(flags()->report_globals);
+ CHECK(AddrIsInMem(g->beg));
+ CHECK(AddrIsAlignedByGranularity(g->beg));
+ CHECK(AddrIsAlignedByGranularity(g->size_with_redzone));
+ if (CanPoisonMemory())
+ PoisonShadowForGlobal(g, 0);
+ // We unpoison the shadow memory for the global but we do not remove it from
+ // the list because that would require O(n^2) time with the current list
+ // implementation. It might not be worth doing anyway.
+
+ // Release ODR indicator.
+ if (UseODRIndicator(g) && g->odr_indicator != UINTPTR_MAX) {
+ u8 *odr_indicator = reinterpret_cast<u8 *>(g->odr_indicator);
+ *odr_indicator = UNREGISTERED;
+ }
+}
+
+void StopInitOrderChecking() {
+ Lock lock(&mu_for_globals);
+ if (!flags()->check_initialization_order || !dynamic_init_globals)
+ return;
+ flags()->check_initialization_order = false;
+ for (uptr i = 0, n = dynamic_init_globals->size(); i < n; ++i) {
+ DynInitGlobal &dyn_g = (*dynamic_init_globals)[i];
+ const Global *g = &dyn_g.g;
+ // Unpoison the whole global.
+ PoisonShadowForGlobal(g, 0);
+ // Poison redzones back.
+ PoisonRedZones(*g);
+ }
+}
+
+static bool IsASCII(unsigned char c) { return /*0x00 <= c &&*/ c <= 0x7F; }
+
+const char *MaybeDemangleGlobalName(const char *name) {
+ // We can spoil names of globals with C linkage, so use an heuristic
+ // approach to check if the name should be demangled.
+ bool should_demangle = false;
+ if (name[0] == '_' && name[1] == 'Z')
+ should_demangle = true;
+ else if (SANITIZER_WINDOWS && name[0] == '\01' && name[1] == '?')
+ should_demangle = true;
+
+ return should_demangle ? Symbolizer::GetOrInit()->Demangle(name) : name;
+}
+
+// Check if the global is a zero-terminated ASCII string. If so, print it.
+void PrintGlobalNameIfASCII(InternalScopedString *str, const __asan_global &g) {
+ for (uptr p = g.beg; p < g.beg + g.size - 1; p++) {
+ unsigned char c = *(unsigned char *)p;
+ if (c == '\0' || !IsASCII(c)) return;
+ }
+ if (*(char *)(g.beg + g.size - 1) != '\0') return;
+ str->append(" '%s' is ascii string '%s'\n", MaybeDemangleGlobalName(g.name),
+ (char *)g.beg);
+}
+
+static const char *GlobalFilename(const __asan_global &g) {
+ const char *res = g.module_name;
+ // Prefer the filename from source location, if is available.
+ if (g.location) res = g.location->filename;
+ CHECK(res);
+ return res;
+}
+
+void PrintGlobalLocation(InternalScopedString *str, const __asan_global &g) {
+ str->append("%s", GlobalFilename(g));
+ if (!g.location) return;
+ if (g.location->line_no) str->append(":%d", g.location->line_no);
+ if (g.location->column_no) str->append(":%d", g.location->column_no);
+}
+
+} // namespace __asan
+
+// ---------------------- Interface ---------------- {{{1
+using namespace __asan;
+
+// Apply __asan_register_globals to all globals found in the same loaded
+// executable or shared library as `flag'. The flag tracks whether globals have
+// already been registered or not for this image.
+void __asan_register_image_globals(uptr *flag) {
+ if (*flag)
+ return;
+ AsanApplyToGlobals(__asan_register_globals, flag);
+ *flag = 1;
+}
+
+// This mirrors __asan_register_image_globals.
+void __asan_unregister_image_globals(uptr *flag) {
+ if (!*flag)
+ return;
+ AsanApplyToGlobals(__asan_unregister_globals, flag);
+ *flag = 0;
+}
+
+void __asan_register_elf_globals(uptr *flag, void *start, void *stop) {
+ if (*flag) return;
+ if (!start) return;
+ CHECK_EQ(0, ((uptr)stop - (uptr)start) % sizeof(__asan_global));
+ __asan_global *globals_start = (__asan_global*)start;
+ __asan_global *globals_stop = (__asan_global*)stop;
+ __asan_register_globals(globals_start, globals_stop - globals_start);
+ *flag = 1;
+}
+
+void __asan_unregister_elf_globals(uptr *flag, void *start, void *stop) {
+ if (!*flag) return;
+ if (!start) return;
+ CHECK_EQ(0, ((uptr)stop - (uptr)start) % sizeof(__asan_global));
+ __asan_global *globals_start = (__asan_global*)start;
+ __asan_global *globals_stop = (__asan_global*)stop;
+ __asan_unregister_globals(globals_start, globals_stop - globals_start);
+ *flag = 0;
+}
+
+// Register an array of globals.
+void __asan_register_globals(__asan_global *globals, uptr n) {
+ if (!flags()->report_globals) return;
+ GET_STACK_TRACE_MALLOC;
+ u32 stack_id = StackDepotPut(stack);
+ Lock lock(&mu_for_globals);
+ if (!global_registration_site_vector) {
+ global_registration_site_vector =
+ new (allocator_for_globals) GlobalRegistrationSiteVector;
+ global_registration_site_vector->reserve(128);
+ }
+ GlobalRegistrationSite site = {stack_id, &globals[0], &globals[n - 1]};
+ global_registration_site_vector->push_back(site);
+ if (flags()->report_globals >= 2) {
+ PRINT_CURRENT_STACK();
+ Printf("=== ID %d; %p %p\n", stack_id, (void *)&globals[0],
+ (void *)&globals[n - 1]);
+ }
+ for (uptr i = 0; i < n; i++) {
+ if (SANITIZER_WINDOWS && globals[i].beg == 0) {
+ // The MSVC incremental linker may pad globals out to 256 bytes. As long
+ // as __asan_global is less than 256 bytes large and its size is a power
+ // of two, we can skip over the padding.
+ static_assert(
+ sizeof(__asan_global) < 256 &&
+ (sizeof(__asan_global) & (sizeof(__asan_global) - 1)) == 0,
+ "sizeof(__asan_global) incompatible with incremental linker padding");
+ // If these are padding bytes, the rest of the global should be zero.
+ CHECK(globals[i].size == 0 && globals[i].size_with_redzone == 0 &&
+ globals[i].name == nullptr && globals[i].module_name == nullptr &&
+ globals[i].odr_indicator == 0);
+ continue;
+ }
+ RegisterGlobal(&globals[i]);
+ }
+
+ // Poison the metadata. It should not be accessible to user code.
+ PoisonShadow(reinterpret_cast<uptr>(globals), n * sizeof(__asan_global),
+ kAsanGlobalRedzoneMagic);
+}
+
+// Unregister an array of globals.
+// We must do this when a shared objects gets dlclosed.
+void __asan_unregister_globals(__asan_global *globals, uptr n) {
+ if (!flags()->report_globals) return;
+ Lock lock(&mu_for_globals);
+ for (uptr i = 0; i < n; i++) {
+ if (SANITIZER_WINDOWS && globals[i].beg == 0) {
+ // Skip globals that look like padding from the MSVC incremental linker.
+ // See comment in __asan_register_globals.
+ continue;
+ }
+ UnregisterGlobal(&globals[i]);
+ }
+
+ // Unpoison the metadata.
+ PoisonShadow(reinterpret_cast<uptr>(globals), n * sizeof(__asan_global), 0);
+}
+
+// This method runs immediately prior to dynamic initialization in each TU,
+// when all dynamically initialized globals are unpoisoned. This method
+// poisons all global variables not defined in this TU, so that a dynamic
+// initializer can only touch global variables in the same TU.
+void __asan_before_dynamic_init(const char *module_name) {
+ if (!flags()->check_initialization_order ||
+ !CanPoisonMemory() ||
+ !dynamic_init_globals)
+ return;
+ bool strict_init_order = flags()->strict_init_order;
+ CHECK(module_name);
+ CHECK(asan_inited);
+ Lock lock(&mu_for_globals);
+ if (flags()->report_globals >= 3)
+ Printf("DynInitPoison module: %s\n", module_name);
+ for (uptr i = 0, n = dynamic_init_globals->size(); i < n; ++i) {
+ DynInitGlobal &dyn_g = (*dynamic_init_globals)[i];
+ const Global *g = &dyn_g.g;
+ if (dyn_g.initialized)
+ continue;
+ if (g->module_name != module_name)
+ PoisonShadowForGlobal(g, kAsanInitializationOrderMagic);
+ else if (!strict_init_order)
+ dyn_g.initialized = true;
+ }
+}
+
+// This method runs immediately after dynamic initialization in each TU, when
+// all dynamically initialized globals except for those defined in the current
+// TU are poisoned. It simply unpoisons all dynamically initialized globals.
+void __asan_after_dynamic_init() {
+ if (!flags()->check_initialization_order ||
+ !CanPoisonMemory() ||
+ !dynamic_init_globals)
+ return;
+ CHECK(asan_inited);
+ Lock lock(&mu_for_globals);
+ // FIXME: Optionally report that we're unpoisoning globals from a module.
+ for (uptr i = 0, n = dynamic_init_globals->size(); i < n; ++i) {
+ DynInitGlobal &dyn_g = (*dynamic_init_globals)[i];
+ const Global *g = &dyn_g.g;
+ if (!dyn_g.initialized) {
+ // Unpoison the whole global.
+ PoisonShadowForGlobal(g, 0);
+ // Poison redzones back.
+ PoisonRedZones(*g);
+ }
+ }
+}