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[ASan] Use debuginfo for symbolization.
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Hint: Looking here because your manual invocation of something in
'check-asan' broke? You need a new symbolizer (after D123538).

An upcoming patch will remove the internal metadata for global
variables. With D123534 and D123538, clang now emits DWARF debug info
for constant strings (the only global variable type it was missing), and
llvm-symbolizer is now able to symbolize all global variable addresses
(where previously it wouldn't give you the file:line information).

Move ASan's runtime over from the internal metadata to DWARF.

Differential Revision: https://reviews.llvm.org/D127552
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@hctim
hctim committed Jun 15, 2022
1 parent 2815bac commit f0ab8d9
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Showing 5 changed files with 51 additions and 35 deletions.
29 changes: 13 additions & 16 deletions compiler-rt/lib/asan/asan_globals.cpp
View file
Expand Up @@ -86,10 +86,11 @@ static void ReportGlobal(const Global &g, const char *prefix) {
"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);

DataInfo info;
Symbolizer::GetOrInit()->SymbolizeData(g.beg, &info);
if (info.line != 0) {
Report(" location: name=%s, %d\n", info.file, info.line);
}
}

Expand Down Expand Up @@ -295,19 +296,15 @@ void PrintGlobalNameIfASCII(InternalScopedString *str, const __asan_global &g) {
(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);
DataInfo info;
Symbolizer::GetOrInit()->SymbolizeData(g.beg, &info);

if (info.line != 0) {
str->append("%s:%d", info.file, info.line);
} else {
str->append("%s", g.module_name);
}
}

} // namespace __asan
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5 changes: 3 additions & 2 deletions compiler-rt/lib/asan/asan_interface_internal.h
View file
Expand Up @@ -53,8 +53,9 @@ extern "C" {
const char *module_name; // Module name as a C string. This pointer is a
// unique identifier of a module.
uptr has_dynamic_init; // Non-zero if the global has dynamic initializer.
__asan_global_source_location *location; // Source location of a global,
// or NULL if it is unknown.
uptr windows_padding; // TODO: Figure out how to remove this padding
// that's simply here to make the MSVC incremental
// linker happy...
uptr odr_indicator; // The address of the ODR indicator symbol.
};

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11 changes: 9 additions & 2 deletions compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp
View file
Expand Up @@ -363,14 +363,21 @@ void ParseSymbolizePCOutput(const char *str, SymbolizedStack *res) {
}
}

// Parses a two-line string in the following format:
// Parses a two- or three-line string in the following format:
// <symbol_name>
// <start_address> <size>
// Used by LLVMSymbolizer and InternalSymbolizer.
// <filename>:<column>
// Used by LLVMSymbolizer and InternalSymbolizer. LLVMSymbolizer added support
// for symbolizing the third line in D123538, but we support the older two-line
// information as well.
void ParseSymbolizeDataOutput(const char *str, DataInfo *info) {
str = ExtractToken(str, "\n", &info->name);
str = ExtractUptr(str, " ", &info->start);
str = ExtractUptr(str, "\n", &info->size);
// Note: If the third line isn't present, these calls will set info.{file,
// line} to empty strings.
str = ExtractToken(str, ":", &info->file);
str = ExtractUptr(str, "\n", &info->line);
}

static void ParseSymbolizeFrameOutput(const char *str,
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20 changes: 10 additions & 10 deletions compiler-rt/test/asan/TestCases/Linux/odr-violation.cpp
View file
Expand Up @@ -7,15 +7,15 @@
// pointers. This setting is not on by default because it's too expensive.
//
// Different size: detect a bug if detect_odr_violation>=1
// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib
// RUN: %clangxx_asan %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib
// RUN: %clangxx_asan -g %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=1 not %run %t-ODR-EXE 2>&1 | FileCheck %s
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t-ODR-EXE 2>&1 | FileCheck %s
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=0 %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 not %run %t-ODR-EXE 2>&1 | FileCheck %s
//
// Same size: report a bug only if detect_odr_violation>=2.
// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib -DSZ=100
// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib -DSZ=100
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=1 %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t-ODR-EXE 2>&1 | FileCheck %s
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 not %run %t-ODR-EXE 2>&1 | FileCheck %s
Expand All @@ -26,18 +26,18 @@
// RUN: rm -f %t.supp
//
// Use private aliases for global variables without indicator symbol.
// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias %s -o %dynamiclib -DSZ=100
// RUN: %clangxx_asan -mllvm -asan-use-private-alias %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias %s -o %dynamiclib -DSZ=100
// RUN: %clangxx_asan -g -mllvm -asan-use-private-alias %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED

// Use private aliases for global variables: use indicator symbol to detect ODR violation.
// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias -mllvm -asan-use-odr-indicator %s -o %dynamiclib -DSZ=100
// RUN: %clangxx_asan -mllvm -asan-use-private-alias -mllvm -asan-use-odr-indicator %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias -mllvm -asan-use-odr-indicator %s -o %dynamiclib -DSZ=100
// RUN: %clangxx_asan -g -mllvm -asan-use-private-alias -mllvm -asan-use-odr-indicator %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 not %run %t-ODR-EXE 2>&1 | FileCheck %s

// Same as above but with clang switches.
// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared -fsanitize-address-use-odr-indicator %s -o %dynamiclib -DSZ=100
// RUN: %clangxx_asan -fsanitize-address-use-odr-indicator %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared -fsanitize-address-use-odr-indicator %s -o %dynamiclib -DSZ=100
// RUN: %clangxx_asan -g -fsanitize-address-use-odr-indicator %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 not %run %t-ODR-EXE 2>&1 | FileCheck %s

// GNU driver doesn't handle .so files properly.
Expand All @@ -55,7 +55,7 @@ namespace foo { char G[SZ]; }
#include <stdio.h>
namespace foo { char G[100]; }
// CHECK: ERROR: AddressSanitizer: odr-violation
// CHECK: size=100 'foo::G' {{.*}}odr-violation.cpp:[[@LINE-2]]:22
// CHECK: size=100 'foo::G' {{.*}}odr-violation.cpp:[[@LINE-2]]
// CHECK: size={{4|100}} 'foo::G'
int main(int argc, char **argv) {
printf("PASS: %p\n", &foo::G);
Expand Down
21 changes: 16 additions & 5 deletions compiler-rt/test/asan/TestCases/global-location.cpp
View file
@@ -1,21 +1,30 @@
// RUN: %clangxx_asan -O2 %s -o %t
// RUN: %clangxx_asan -g -O2 %s -o %t
// RUN: not %run %t g 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=GLOB
// RUN: not %run %t c 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CLASS_STATIC
// RUN: not %run %t f 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=FUNC_STATIC
// RUN: not %run %t l 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=LITERAL

// RUN: %clangxx_asan -O2 %s -o %t
// RUN: llvm-strip -s %t
// RUN: not %run %t g 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=GLOB-NO-G
// RUN: not %run %t c 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CLASS_STATIC-NO-G
// RUN: not %run %t f 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=FUNC_STATIC-NO-G
// RUN: not %run %t l 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=LITERAL-NO-G

// CHECK: AddressSanitizer: global-buffer-overflow

#include <string.h>

struct C {
static int array[10];
// CLASS_STATIC: 0x{{.*}} is located 4 bytes to the right of global variable 'C::array' defined in '{{.*}}global-location.cpp:[[@LINE-1]]' {{.*}} of size 40
// CLASS_STATIC-NO-G: 0x{{.*}} is located 4 bytes to the right of global variable 'C::array' defined in '{{.*}}global-location.cpp' {{.*}} of size 40
};

int global[10];
// GLOB: 0x{{.*}} is located 4 bytes to the right of global variable 'global' defined in '{{.*}}global-location.cpp:[[@LINE-1]]:5' {{.*}} of size 40
// GLOB: 0x{{.*}} is located 4 bytes to the right of global variable 'global' defined in '{{.*}}global-location.cpp:[[@LINE-1]]' {{.*}} of size 40
// GLOB-NO-G: 0x{{.*}} is located 4 bytes to the right of global variable 'global' defined in '{{.*}}global-location.cpp' {{.*}} of size 40
int C::array[10];
// CLASS_STATIC: 0x{{.*}} is located 4 bytes to the right of global variable 'C::array' defined in '{{.*}}global-location.cpp:[[@LINE-1]]:8' {{.*}} of size 40

int main(int argc, char **argv) {
int one = argc - 1;
Expand All @@ -24,12 +33,14 @@ int main(int argc, char **argv) {
case 'c': return C::array[one * 11];
case 'f':
static int array[10];
// FUNC_STATIC: 0x{{.*}} is located 4 bytes to the right of global variable 'array' defined in '{{.*}}global-location.cpp:[[@LINE-1]]:16' {{.*}} of size 40
// FUNC_STATIC: 0x{{.*}} is located 4 bytes to the right of global variable 'array' defined in '{{.*}}global-location.cpp:[[@LINE-1]]' {{.*}} of size 40
// FUNC_STATIC-NO-G: 0x{{.*}} is located 4 bytes to the right of global variable 'array' defined in '{{.*}}global-location.cpp' {{.*}} of size 40
memset(array, 0, 10);
return array[one * 11];
case 'l':
const char *str = "0123456789";
// LITERAL: 0x{{.*}} is located 0 bytes to the right of global variable {{.*}} defined in '{{.*}}global-location.cpp:[[@LINE-1]]:23' {{.*}} of size 11
// LITERAL: 0x{{.*}} is located 0 bytes to the right of global variable {{.*}} defined in '{{.*}}global-location.cpp:[[@LINE-1]]' {{.*}} of size 11
// LITERAL-NO-G: 0x{{.*}} is located 0 bytes to the right of global variable {{.*}} defined in '{{.*}}global-location.cpp' {{.*}} of size 11
return str[one * 11];
}
return 0;
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