[compiler-rt] r218538 - [compiler-rt] recommit of r218481: ASan debugging API for report info extraction and locating addresses
Kuba Brecka
kuba.brecka at gmail.com
Fri Sep 26 12:15:33 PDT 2014
Author: kuba.brecka
Date: Fri Sep 26 14:15:32 2014
New Revision: 218538
URL: http://llvm.org/viewvc/llvm-project?rev=218538&view=rev
Log:
[compiler-rt] recommit of r218481: ASan debugging API for report info extraction and locating addresses
Reviewed at http://reviews.llvm.org/D4527
Fixed a test case failure on 32-bit Linux, I did right shift on intptr_t, instead it should have been uintptr_t.
Added:
compiler-rt/trunk/test/asan/TestCases/debug_locate.cc
compiler-rt/trunk/test/asan/TestCases/debug_report.cc
Modified:
compiler-rt/trunk/include/sanitizer/asan_interface.h
compiler-rt/trunk/lib/asan/asan_debugging.cc
compiler-rt/trunk/lib/asan/asan_globals.cc
compiler-rt/trunk/lib/asan/asan_interface_internal.h
compiler-rt/trunk/lib/asan/asan_report.cc
compiler-rt/trunk/lib/asan/asan_report.h
Modified: compiler-rt/trunk/include/sanitizer/asan_interface.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/include/sanitizer/asan_interface.h?rev=218538&r1=218537&r2=218538&view=diff
==============================================================================
--- compiler-rt/trunk/include/sanitizer/asan_interface.h (original)
+++ compiler-rt/trunk/include/sanitizer/asan_interface.h Fri Sep 26 14:15:32 2014
@@ -62,6 +62,32 @@ extern "C" {
// Print the description of addr (useful when debugging in gdb).
void __asan_describe_address(void *addr);
+ // Useful for calling from a debugger to get information about an ASan error.
+ // Returns 1 if an error has been (or is being) reported, otherwise returns 0.
+ int __asan_report_present();
+
+ // Useful for calling from a debugger to get information about an ASan error.
+ // If an error has been (or is being) reported, the following functions return
+ // the pc, bp, sp, address, access type (0 = read, 1 = write), access size and
+ // bug description (e.g. "heap-use-after-free"). Otherwise they return 0.
+ void *__asan_get_report_pc();
+ void *__asan_get_report_bp();
+ void *__asan_get_report_sp();
+ void *__asan_get_report_address();
+ int __asan_get_report_access_type();
+ size_t __asan_get_report_access_size();
+ const char *__asan_get_report_description();
+
+ // Useful for calling from the debugger to get information about a pointer.
+ // Returns the category of the given pointer as a constant string.
+ // Possible return values are "global", "stack", "stack-fake", "heap",
+ // "heap-invalid", "shadow-low", "shadow-gap", "shadow-high", "unknown".
+ // If global or stack, tries to also return the variable name, address and
+ // size. If heap, tries to return the chunk address and size. 'name' should
+ // point to an allocated buffer of size 'name_size'.
+ const char *__asan_locate_address(void *addr, char *name, size_t name_size,
+ void **region_address, size_t *region_size);
+
// Useful for calling from the debugger to get the allocation stack trace
// and thread ID for a heap address. Stores up to 'size' frames into 'trace',
// returns the number of stored frames or 0 on error.
Modified: compiler-rt/trunk/lib/asan/asan_debugging.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_debugging.cc?rev=218538&r1=218537&r2=218538&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_debugging.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_debugging.cc Fri Sep 26 14:15:32 2014
@@ -17,10 +17,70 @@
#include "asan_flags.h"
#include "asan_internal.h"
#include "asan_mapping.h"
+#include "asan_report.h"
#include "asan_thread.h"
namespace __asan {
+void GetInfoForStackVar(uptr addr, AddressDescription *descr, AsanThread *t) {
+ descr->name[0] = 0;
+ descr->region_address = 0;
+ descr->region_size = 0;
+ descr->region_kind = "stack";
+
+ uptr offset = 0;
+ uptr frame_pc = 0;
+ const char *frame_descr = t->GetFrameNameByAddr(addr, &offset, &frame_pc);
+ InternalMmapVector<StackVarDescr> vars(16);
+ if (!ParseFrameDescription(frame_descr, &vars)) {
+ return;
+ }
+
+ for (uptr i = 0; i < vars.size(); i++) {
+ if (offset <= vars[i].beg + vars[i].size) {
+ internal_strncat(descr->name, vars[i].name_pos,
+ Min(descr->name_size, vars[i].name_len));
+ descr->region_address = addr - (offset - vars[i].beg);
+ descr->region_size = vars[i].size;
+ return;
+ }
+ }
+}
+
+void GetInfoForHeapAddress(uptr addr, AddressDescription *descr) {
+ AsanChunkView chunk = FindHeapChunkByAddress(addr);
+
+ descr->name[0] = 0;
+ descr->region_address = 0;
+ descr->region_size = 0;
+
+ if (!chunk.IsValid()) {
+ descr->region_kind = "heap-invalid";
+ return;
+ }
+
+ descr->region_address = chunk.Beg();
+ descr->region_size = chunk.UsedSize();
+ descr->region_kind = "heap";
+}
+
+void AsanLocateAddress(uptr addr, AddressDescription *descr) {
+ if (DescribeAddressIfShadow(addr, descr, /* print */ false)) {
+ return;
+ }
+ if (GetInfoForAddressIfGlobal(addr, descr)) {
+ return;
+ }
+ asanThreadRegistry().Lock();
+ AsanThread *thread = FindThreadByStackAddress(addr);
+ asanThreadRegistry().Unlock();
+ if (thread) {
+ GetInfoForStackVar(addr, descr, thread);
+ return;
+ }
+ GetInfoForHeapAddress(addr, descr);
+}
+
uptr AsanGetStack(uptr addr, uptr *trace, uptr size, u32 *thread_id,
bool alloc_stack) {
AsanChunkView chunk = FindHeapChunkByAddress(addr);
@@ -56,6 +116,16 @@ uptr AsanGetStack(uptr addr, uptr *trace
using namespace __asan;
SANITIZER_INTERFACE_ATTRIBUTE
+const char *__asan_locate_address(uptr addr, char *name, uptr name_size,
+ uptr *region_address, uptr *region_size) {
+ AddressDescription descr = { name, name_size, 0, 0, 0 };
+ AsanLocateAddress(addr, &descr);
+ if (region_address) *region_address = descr.region_address;
+ if (region_size) *region_size = descr.region_size;
+ return descr.region_kind;
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
uptr __asan_get_alloc_stack(uptr addr, uptr *trace, uptr size, u32 *thread_id) {
return AsanGetStack(addr, trace, size, thread_id, /* alloc_stack */ true);
}
Modified: compiler-rt/trunk/lib/asan/asan_globals.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_globals.cc?rev=218538&r1=218537&r2=218538&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_globals.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_globals.cc Fri Sep 26 14:15:32 2014
@@ -71,6 +71,14 @@ ALWAYS_INLINE void PoisonRedZones(const
}
}
+const uptr kMinimalDistanceFromAnotherGlobal = 64;
+
+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\n",
prefix, &g, (void *)g.beg, g.size, g.size_with_redzone, g.name,
@@ -82,19 +90,45 @@ static void ReportGlobal(const Global &g
}
}
-bool DescribeAddressIfGlobal(uptr addr, uptr size) {
+static bool DescribeOrGetInfoIfGlobal(uptr addr, uptr size, bool print,
+ Global *output_global) {
if (!flags()->report_globals) return false;
BlockingMutexLock lock(&mu_for_globals);
bool res = false;
for (ListOfGlobals *l = list_of_all_globals; l; l = l->next) {
const Global &g = *l->g;
- if (flags()->report_globals >= 2)
- ReportGlobal(g, "Search");
- res |= DescribeAddressRelativeToGlobal(addr, size, g);
+ if (print) {
+ if (flags()->report_globals >= 2)
+ ReportGlobal(g, "Search");
+ res |= DescribeAddressRelativeToGlobal(addr, size, g);
+ } else {
+ if (IsAddressNearGlobal(addr, g)) {
+ CHECK(output_global);
+ *output_global = g;
+ return true;
+ }
+ }
}
return res;
}
+bool DescribeAddressIfGlobal(uptr addr, uptr size) {
+ return DescribeOrGetInfoIfGlobal(addr, size, /* print */ true,
+ /* output_global */ nullptr);
+}
+
+bool GetInfoForAddressIfGlobal(uptr addr, AddressDescription *descr) {
+ Global g = {};
+ if (DescribeOrGetInfoIfGlobal(addr, /* size */ 1, /* print */ false, &g)) {
+ internal_strncpy(descr->name, g.name, descr->name_size);
+ descr->region_address = g.beg;
+ descr->region_size = g.size;
+ descr->region_kind = "global";
+ return true;
+ }
+ return false;
+}
+
u32 FindRegistrationSite(const Global *g) {
CHECK(global_registration_site_vector);
for (uptr i = 0, n = global_registration_site_vector->size(); i < n; i++) {
Modified: compiler-rt/trunk/lib/asan/asan_interface_internal.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_interface_internal.h?rev=218538&r1=218537&r2=218538&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_interface_internal.h (original)
+++ compiler-rt/trunk/lib/asan/asan_interface_internal.h Fri Sep 26 14:15:32 2014
@@ -91,6 +91,28 @@ extern "C" {
void __asan_describe_address(uptr addr);
SANITIZER_INTERFACE_ATTRIBUTE
+ int __asan_report_present();
+
+ SANITIZER_INTERFACE_ATTRIBUTE
+ uptr __asan_get_report_pc();
+ SANITIZER_INTERFACE_ATTRIBUTE
+ uptr __asan_get_report_bp();
+ SANITIZER_INTERFACE_ATTRIBUTE
+ uptr __asan_get_report_sp();
+ SANITIZER_INTERFACE_ATTRIBUTE
+ uptr __asan_get_report_address();
+ SANITIZER_INTERFACE_ATTRIBUTE
+ int __asan_get_report_access_type();
+ SANITIZER_INTERFACE_ATTRIBUTE
+ uptr __asan_get_report_access_size();
+ SANITIZER_INTERFACE_ATTRIBUTE
+ const char * __asan_get_report_description();
+
+ SANITIZER_INTERFACE_ATTRIBUTE
+ const char * __asan_locate_address(uptr addr, char *name, uptr name_size,
+ uptr *region_address, uptr *region_size);
+
+ SANITIZER_INTERFACE_ATTRIBUTE
uptr __asan_get_alloc_stack(uptr addr, uptr *trace, uptr size,
u32 *thread_id);
Modified: compiler-rt/trunk/lib/asan/asan_report.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_report.cc?rev=218538&r1=218537&r2=218538&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_report.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_report.cc Fri Sep 26 14:15:32 2014
@@ -31,6 +31,19 @@ static char *error_message_buffer = 0;
static uptr error_message_buffer_pos = 0;
static uptr error_message_buffer_size = 0;
+struct ReportData {
+ uptr pc;
+ uptr sp;
+ uptr bp;
+ uptr addr;
+ bool is_write;
+ uptr access_size;
+ const char *description;
+};
+
+static bool report_happened = false;
+static ReportData report_data = {};
+
void AppendToErrorMessageBuffer(const char *buffer) {
if (error_message_buffer) {
uptr length = internal_strlen(buffer);
@@ -262,9 +275,7 @@ static void PrintGlobalLocation(Internal
bool DescribeAddressRelativeToGlobal(uptr addr, uptr size,
const __asan_global &g) {
- static const uptr kMinimalDistanceFromAnotherGlobal = 64;
- if (addr <= g.beg - kMinimalDistanceFromAnotherGlobal) return false;
- if (addr >= g.beg + g.size_with_redzone) return false;
+ if (!IsAddressNearGlobal(addr, g)) return false;
InternalScopedString str(4096);
Decorator d;
str.append("%s", d.Location());
@@ -290,21 +301,20 @@ bool DescribeAddressRelativeToGlobal(upt
return true;
}
-bool DescribeAddressIfShadow(uptr addr) {
+bool DescribeAddressIfShadow(uptr addr, AddressDescription *descr, bool print) {
if (AddrIsInMem(addr))
return false;
- static const char kAddrInShadowReport[] =
- "Address %p is located in the %s.\n";
- if (AddrIsInShadowGap(addr)) {
- Printf(kAddrInShadowReport, addr, "shadow gap area");
- return true;
- }
- if (AddrIsInHighShadow(addr)) {
- Printf(kAddrInShadowReport, addr, "high shadow area");
- return true;
- }
- if (AddrIsInLowShadow(addr)) {
- Printf(kAddrInShadowReport, addr, "low shadow area");
+ const char *area_type = nullptr;
+ if (AddrIsInShadowGap(addr)) area_type = "shadow gap";
+ else if (AddrIsInHighShadow(addr)) area_type = "high shadow";
+ else if (AddrIsInLowShadow(addr)) area_type = "low shadow";
+ if (area_type != nullptr) {
+ if (print) {
+ Printf("Address %p is located in the %s area.\n", addr, area_type);
+ } else {
+ CHECK(descr);
+ descr->region_kind = area_type;
+ }
return true;
}
CHECK(0 && "Address is not in memory and not in shadow?");
@@ -582,7 +592,7 @@ void DescribeThread(AsanThreadContext *c
// immediately after printing error report.
class ScopedInErrorReport {
public:
- ScopedInErrorReport() {
+ explicit ScopedInErrorReport(ReportData *report = nullptr) {
static atomic_uint32_t num_calls;
static u32 reporting_thread_tid;
if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
@@ -602,6 +612,8 @@ class ScopedInErrorReport {
// Die() to bypass any additional checks.
internal__exit(flags()->exitcode);
}
+ if (report) report_data = *report;
+ report_happened = true;
ASAN_ON_ERROR();
// Make sure the registry and sanitizer report mutexes are locked while
// we're printing an error report.
@@ -922,8 +934,6 @@ using namespace __asan; // NOLINT
void __asan_report_error(uptr pc, uptr bp, uptr sp, uptr addr, int is_write,
uptr access_size) {
- ScopedInErrorReport in_report;
-
// Determine the error type.
const char *bug_descr = "unknown-crash";
if (AddrIsInMem(addr)) {
@@ -971,6 +981,11 @@ void __asan_report_error(uptr pc, uptr b
break;
}
}
+
+ ReportData report = { pc, sp, bp, addr, (bool)is_write, access_size,
+ bug_descr };
+ ScopedInErrorReport in_report(&report);
+
Decorator d;
Printf("%s", d.Warning());
Report("ERROR: AddressSanitizer: %s on address "
@@ -1012,6 +1027,38 @@ void __asan_describe_address(uptr addr)
asanThreadRegistry().Unlock();
}
+int __asan_report_present() {
+ return report_happened ? 1 : 0;
+}
+
+uptr __asan_get_report_pc() {
+ return report_data.pc;
+}
+
+uptr __asan_get_report_bp() {
+ return report_data.bp;
+}
+
+uptr __asan_get_report_sp() {
+ return report_data.sp;
+}
+
+uptr __asan_get_report_address() {
+ return report_data.addr;
+}
+
+int __asan_get_report_access_type() {
+ return report_data.is_write ? 1 : 0;
+}
+
+uptr __asan_get_report_access_size() {
+ return report_data.access_size;
+}
+
+const char *__asan_get_report_description() {
+ return report_data.description;
+}
+
extern "C" {
SANITIZER_INTERFACE_ATTRIBUTE
void __sanitizer_ptr_sub(void *a, void *b) {
Modified: compiler-rt/trunk/lib/asan/asan_report.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_report.h?rev=218538&r1=218537&r2=218538&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_report.h (original)
+++ compiler-rt/trunk/lib/asan/asan_report.h Fri Sep 26 14:15:32 2014
@@ -25,13 +25,24 @@ struct StackVarDescr {
uptr name_len;
};
+struct AddressDescription {
+ char *name;
+ uptr name_size;
+ uptr region_address;
+ uptr region_size;
+ const char *region_kind;
+};
+
// The following functions prints address description depending
// on the memory type (shadow/heap/stack/global).
void DescribeHeapAddress(uptr addr, uptr access_size);
bool DescribeAddressIfGlobal(uptr addr, uptr access_size);
bool DescribeAddressRelativeToGlobal(uptr addr, uptr access_size,
const __asan_global &g);
-bool DescribeAddressIfShadow(uptr addr);
+bool IsAddressNearGlobal(uptr addr, const __asan_global &g);
+bool GetInfoForAddressIfGlobal(uptr addr, AddressDescription *descr);
+bool DescribeAddressIfShadow(uptr addr, AddressDescription *descr = nullptr,
+ bool print = true);
bool ParseFrameDescription(const char *frame_descr,
InternalMmapVector<StackVarDescr> *vars);
bool DescribeAddressIfStack(uptr addr, uptr access_size);
Added: compiler-rt/trunk/test/asan/TestCases/debug_locate.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/asan/TestCases/debug_locate.cc?rev=218538&view=auto
==============================================================================
--- compiler-rt/trunk/test/asan/TestCases/debug_locate.cc (added)
+++ compiler-rt/trunk/test/asan/TestCases/debug_locate.cc Fri Sep 26 14:15:32 2014
@@ -0,0 +1,80 @@
+// Checks the ASan memory address type debugging API, makes sure it returns
+// the correct memory type for heap, stack, global and shadow addresses and
+// that it correctly finds out which region (and name and size) the address
+// belongs to.
+// RUN: %clangxx_asan -O0 %s -o %t && %run %t 2>&1
+
+#include <assert.h>
+#include <sanitizer/asan_interface.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+int global_var;
+
+int main() {
+ int local_var;
+ char *heap_ptr = (char *)malloc(10);
+
+ char name[100];
+ void *region_address;
+ size_t region_size;
+ const char *type;
+
+ type = __asan_locate_address(&global_var, name, 100,
+ ®ion_address, ®ion_size);
+ assert(0 == strcmp(name, "global_var"));
+ assert(0 == strcmp(type, "global"));
+ assert(region_address == &global_var);
+ assert(region_size == sizeof(global_var));
+
+ type = __asan_locate_address((char *)(&global_var)+1, name, 100,
+ ®ion_address, ®ion_size);
+ assert(0 == strcmp(name, "global_var"));
+ assert(0 == strcmp(type, "global"));
+ assert(region_address == &global_var);
+ assert(region_size == sizeof(global_var));
+
+ type = __asan_locate_address(&local_var, name, 100,
+ ®ion_address, ®ion_size);
+ assert(0 == strcmp(name, "local_var"));
+ assert(0 == strcmp(type, "stack"));
+ assert(region_address == &local_var);
+ assert(region_size == sizeof(local_var));
+
+ type = __asan_locate_address((char *)(&local_var)+1, name, 100,
+ ®ion_address, ®ion_size);
+ assert(0 == strcmp(name, "local_var"));
+ assert(0 == strcmp(type, "stack"));
+ assert(region_address == &local_var);
+ assert(region_size == sizeof(local_var));
+
+ type = __asan_locate_address(heap_ptr, name, 100,
+ ®ion_address, ®ion_size);
+ assert(0 == strcmp(type, "heap"));
+ assert(region_address == heap_ptr);
+ assert(10 == region_size);
+
+ type = __asan_locate_address(heap_ptr+1, name, 100,
+ ®ion_address, ®ion_size);
+ assert(0 == strcmp(type, "heap"));
+ assert(region_address == heap_ptr);
+ assert(10 == region_size);
+
+ size_t shadow_scale;
+ size_t shadow_offset;
+ __asan_get_shadow_mapping(&shadow_scale, &shadow_offset);
+
+ uintptr_t shadow_ptr = (((uintptr_t)heap_ptr) >> shadow_scale)
+ + shadow_offset;
+ type = __asan_locate_address((void *)shadow_ptr, NULL, 0, NULL, NULL);
+ assert((0 == strcmp(type, "high shadow")) || 0 == strcmp(type, "low shadow"));
+
+ uintptr_t shadow_gap = (shadow_ptr >> shadow_scale) + shadow_offset;
+ type = __asan_locate_address((void *)shadow_gap, NULL, 0, NULL, NULL);
+ assert(0 == strcmp(type, "shadow gap"));
+
+ free(heap_ptr);
+
+ return 0;
+}
Added: compiler-rt/trunk/test/asan/TestCases/debug_report.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/asan/TestCases/debug_report.cc?rev=218538&view=auto
==============================================================================
--- compiler-rt/trunk/test/asan/TestCases/debug_report.cc (added)
+++ compiler-rt/trunk/test/asan/TestCases/debug_report.cc Fri Sep 26 14:15:32 2014
@@ -0,0 +1,48 @@
+// Checks that the ASan debugging API for getting report information
+// returns correct values.
+// RUN: %clangxx_asan -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s
+
+#include <sanitizer/asan_interface.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int main() {
+ char *heap_ptr = (char *)malloc(10);
+ free(heap_ptr);
+ int present = __asan_report_present();
+ fprintf(stderr, "%s\n", (present == 0) ? "no report" : "");
+ // CHECK: no report
+ heap_ptr[0] = 'A'; // BOOM
+ return 0;
+}
+
+void __asan_on_error() {
+ int present = __asan_report_present();
+ void *pc = __asan_get_report_pc();
+ void *bp = __asan_get_report_bp();
+ void *sp = __asan_get_report_sp();
+ void *addr = __asan_get_report_address();
+ int is_write = __asan_get_report_access_type();
+ size_t access_size = __asan_get_report_access_size();
+ const char *description = __asan_get_report_description();
+
+ fprintf(stderr, "%s\n", (present == 1) ? "report" : "");
+ // CHECK: report
+ fprintf(stderr, "pc: %p\n", pc);
+ // CHECK: pc: 0x[[PC:[0-9a-f]+]]
+ fprintf(stderr, "bp: %p\n", bp);
+ // CHECK: bp: 0x[[BP:[0-9a-f]+]]
+ fprintf(stderr, "sp: %p\n", sp);
+ // CHECK: sp: 0x[[SP:[0-9a-f]+]]
+ fprintf(stderr, "addr: %p\n", addr);
+ // CHECK: addr: 0x[[ADDR:[0-9a-f]+]]
+ fprintf(stderr, "type: %s\n", (is_write ? "write" : "read"));
+ // CHECK: type: write
+ fprintf(stderr, "access_size: %ld\n", access_size);
+ // CHECK: access_size: 1
+ fprintf(stderr, "description: %s\n", description);
+ // CHECK: description: heap-use-after-free
+}
+
+// CHECK: AddressSanitizer: heap-use-after-free on address {{0x0*}}[[ADDR]] at pc {{0x0*}}[[PC]] bp {{0x0*}}[[BP]] sp {{0x0*}}[[SP]]
+// CHECK: WRITE of size 1 at {{0x0*}}[[ADDR]] thread T0
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