blob: 256f7648c4cb9d41d5e5e07aa7b55a421ace600a [file] [log] [blame]
// Copyright (c) 2010, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com>
// stackwalker_arm_unittest.cc: Unit tests for StackwalkerARM class.
#include <string.h>
#include <string>
#include <vector>
#include "breakpad_googletest_includes.h"
#include "common/test_assembler.h"
#include "common/using_std_string.h"
#include "google_breakpad/common/minidump_format.h"
#include "google_breakpad/processor/basic_source_line_resolver.h"
#include "google_breakpad/processor/call_stack.h"
#include "google_breakpad/processor/code_module.h"
#include "google_breakpad/processor/source_line_resolver_interface.h"
#include "google_breakpad/processor/stack_frame_cpu.h"
#include "processor/stackwalker_unittest_utils.h"
#include "processor/stackwalker_arm.h"
#include "processor/windows_frame_info.h"
using google_breakpad::BasicSourceLineResolver;
using google_breakpad::CallStack;
using google_breakpad::CodeModule;
using google_breakpad::StackFrameSymbolizer;
using google_breakpad::StackFrame;
using google_breakpad::StackFrameARM;
using google_breakpad::Stackwalker;
using google_breakpad::StackwalkerARM;
using google_breakpad::SystemInfo;
using google_breakpad::WindowsFrameInfo;
using google_breakpad::test_assembler::kLittleEndian;
using google_breakpad::test_assembler::Label;
using google_breakpad::test_assembler::Section;
using std::vector;
using testing::_;
using testing::AnyNumber;
using testing::DoAll;
using testing::Return;
using testing::SetArgumentPointee;
using testing::Test;
class StackwalkerARMFixture {
public:
StackwalkerARMFixture()
: stack_section(kLittleEndian),
// Give the two modules reasonable standard locations and names
// for tests to play with.
module1(0x40000000, 0x10000, "module1", "version1"),
module2(0x50000000, 0x10000, "module2", "version2") {
// Identify the system as a Linux system.
system_info.os = "Linux";
system_info.os_short = "linux";
system_info.os_version = "Lugubrious Labrador";
system_info.cpu = "arm";
system_info.cpu_info = "";
// Put distinctive values in the raw CPU context.
BrandContext(&raw_context);
// Create some modules with some stock debugging information.
modules.Add(&module1);
modules.Add(&module2);
// By default, none of the modules have symbol info; call
// SetModuleSymbols to override this.
EXPECT_CALL(supplier, GetCStringSymbolData(_, _, _, _, _))
.WillRepeatedly(Return(MockSymbolSupplier::NOT_FOUND));
// Avoid GMOCK WARNING "Uninteresting mock function call - returning
// directly" for FreeSymbolData().
EXPECT_CALL(supplier, FreeSymbolData(_)).Times(AnyNumber());
// Reset max_frames_scanned since it's static.
Stackwalker::set_max_frames_scanned(1024);
}
// Set the Breakpad symbol information that supplier should return for
// MODULE to INFO.
void SetModuleSymbols(MockCodeModule *module, const string &info) {
size_t buffer_size;
char *buffer = supplier.CopySymbolDataAndOwnTheCopy(info, &buffer_size);
EXPECT_CALL(supplier, GetCStringSymbolData(module, &system_info, _, _, _))
.WillRepeatedly(DoAll(SetArgumentPointee<3>(buffer),
SetArgumentPointee<4>(buffer_size),
Return(MockSymbolSupplier::FOUND)));
}
// Populate stack_region with the contents of stack_section. Use
// stack_section.start() as the region's starting address.
void RegionFromSection() {
string contents;
ASSERT_TRUE(stack_section.GetContents(&contents));
stack_region.Init(stack_section.start().Value(), contents);
}
// Fill RAW_CONTEXT with pseudo-random data, for round-trip checking.
void BrandContext(MDRawContextARM *raw_context) {
uint8_t x = 173;
for (size_t i = 0; i < sizeof(*raw_context); i++)
reinterpret_cast<uint8_t *>(raw_context)[i] = (x += 17);
}
SystemInfo system_info;
MDRawContextARM raw_context;
Section stack_section;
MockMemoryRegion stack_region;
MockCodeModule module1;
MockCodeModule module2;
MockCodeModules modules;
MockSymbolSupplier supplier;
BasicSourceLineResolver resolver;
CallStack call_stack;
const vector<StackFrame *> *frames;
};
class SanityCheck: public StackwalkerARMFixture, public Test { };
TEST_F(SanityCheck, NoResolver) {
// Since we have no call frame information, and all unwinding
// requires call frame information, the stack walk will end after
// the first frame.
StackFrameSymbolizer frame_symbolizer(NULL, NULL);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules,
&frame_symbolizer);
// This should succeed even without a resolver or supplier.
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(0U, modules_without_symbols.size());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(1U, frames->size());
StackFrameARM *frame = static_cast<StackFrameARM *>(frames->at(0));
// Check that the values from the original raw context made it
// through to the context in the stack frame.
EXPECT_EQ(0, memcmp(&raw_context, &frame->context, sizeof(raw_context)));
}
class GetContextFrame: public StackwalkerARMFixture, public Test { };
TEST_F(GetContextFrame, Simple) {
// Since we have no call frame information, and all unwinding
// requires call frame information, the stack walk will end after
// the first frame.
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules,
&frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(0U, modules_without_symbols.size());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(1U, frames->size());
StackFrameARM *frame = static_cast<StackFrameARM *>(frames->at(0));
// Check that the values from the original raw context made it
// through to the context in the stack frame.
EXPECT_EQ(0, memcmp(&raw_context, &frame->context, sizeof(raw_context)));
}
// The stackwalker should be able to produce the context frame even
// without stack memory present.
TEST_F(GetContextFrame, NoStackMemory) {
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, NULL, &modules,
&frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(0U, modules_without_symbols.size());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(1U, frames->size());
StackFrameARM *frame = static_cast<StackFrameARM *>(frames->at(0));
// Check that the values from the original raw context made it
// through to the context in the stack frame.
EXPECT_EQ(0, memcmp(&raw_context, &frame->context, sizeof(raw_context)));
}
class GetCallerFrame: public StackwalkerARMFixture, public Test { };
TEST_F(GetCallerFrame, ScanWithoutSymbols) {
// When the stack walker resorts to scanning the stack,
// only addresses located within loaded modules are
// considered valid return addresses.
// Force scanning through three frames to ensure that the
// stack pointer is set properly in scan-recovered frames.
stack_section.start() = 0x80000000;
uint32_t return_address1 = 0x50000100;
uint32_t return_address2 = 0x50000900;
Label frame1_sp, frame2_sp;
stack_section
// frame 0
.Append(16, 0) // space
.D32(0x40090000) // junk that's not
.D32(0x60000000) // a return address
.D32(return_address1) // actual return address
// frame 1
.Mark(&frame1_sp)
.Append(16, 0) // space
.D32(0xF0000000) // more junk
.D32(0x0000000D)
.D32(return_address2) // actual return address
// frame 2
.Mark(&frame2_sp)
.Append(32, 0); // end of stack
RegionFromSection();
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510;
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value();
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules,
&frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(2U, modules_without_symbols.size());
ASSERT_EQ("module1", modules_without_symbols[0]->debug_file());
ASSERT_EQ("module2", modules_without_symbols[1]->debug_file());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(3U, frames->size());
StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0));
EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust);
ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity);
EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context)));
StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1));
EXPECT_EQ(StackFrame::FRAME_TRUST_SCAN, frame1->trust);
ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_SP),
frame1->context_validity);
EXPECT_EQ(return_address1, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]);
StackFrameARM *frame2 = static_cast<StackFrameARM *>(frames->at(2));
EXPECT_EQ(StackFrame::FRAME_TRUST_SCAN, frame2->trust);
ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_SP),
frame2->context_validity);
EXPECT_EQ(return_address2, frame2->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(frame2_sp.Value(), frame2->context.iregs[MD_CONTEXT_ARM_REG_SP]);
}
TEST_F(GetCallerFrame, ScanWithFunctionSymbols) {
// During stack scanning, if a potential return address
// is located within a loaded module that has symbols,
// it is only considered a valid return address if it
// lies within a function's bounds.
stack_section.start() = 0x80000000;
uint32_t return_address = 0x50000200;
Label frame1_sp;
stack_section
// frame 0
.Append(16, 0) // space
.D32(0x40090000) // junk that's not
.D32(0x60000000) // a return address
.D32(0x40001000) // a couple of plausible addresses
.D32(0x5000F000) // that are not within functions
.D32(return_address) // actual return address
// frame 1
.Mark(&frame1_sp)
.Append(32, 0); // end of stack
RegionFromSection();
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40000200;
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value();
SetModuleSymbols(&module1,
// The youngest frame's function.
"FUNC 100 400 10 monotreme\n");
SetModuleSymbols(&module2,
// The calling frame's function.
"FUNC 100 400 10 marsupial\n");
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules,
&frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(0U, modules_without_symbols.size());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(2U, frames->size());
StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0));
EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust);
ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity);
EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context)));
EXPECT_EQ("monotreme", frame0->function_name);
EXPECT_EQ(0x40000100U, frame0->function_base);
StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1));
EXPECT_EQ(StackFrame::FRAME_TRUST_SCAN, frame1->trust);
ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_SP),
frame1->context_validity);
EXPECT_EQ(return_address, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]);
EXPECT_EQ("marsupial", frame1->function_name);
EXPECT_EQ(0x50000100U, frame1->function_base);
}
TEST_F(GetCallerFrame, ScanFirstFrame) {
// If the stackwalker resorts to stack scanning, it will scan much
// farther to find the caller of the context frame.
stack_section.start() = 0x80000000;
uint32_t return_address1 = 0x50000100;
uint32_t return_address2 = 0x50000900;
Label frame1_sp, frame2_sp;
stack_section
// frame 0
.Append(32, 0) // space
.D32(0x40090000) // junk that's not
.D32(0x60000000) // a return address
.Append(96, 0) // more space
.D32(return_address1) // actual return address
// frame 1
.Mark(&frame1_sp)
.Append(32, 0) // space
.D32(0xF0000000) // more junk
.D32(0x0000000D)
.Append(136, 0) // more space
.D32(return_address2) // actual return address
// (won't be found)
// frame 2
.Mark(&frame2_sp)
.Append(32, 0); // end of stack
RegionFromSection();
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510;
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value();
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules,
&frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(2U, modules_without_symbols.size());
ASSERT_EQ("module1", modules_without_symbols[0]->debug_file());
ASSERT_EQ("module2", modules_without_symbols[1]->debug_file());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(2U, frames->size());
StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0));
EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust);
ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity);
EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context)));
StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1));
EXPECT_EQ(StackFrame::FRAME_TRUST_SCAN, frame1->trust);
ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_SP),
frame1->context_validity);
EXPECT_EQ(return_address1, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]);
}
// Test that set_max_frames_scanned prevents using stack scanning
// to find caller frames.
TEST_F(GetCallerFrame, ScanningNotAllowed) {
// When the stack walker resorts to scanning the stack,
// only addresses located within loaded modules are
// considered valid return addresses.
stack_section.start() = 0x80000000;
uint32_t return_address1 = 0x50000100;
uint32_t return_address2 = 0x50000900;
Label frame1_sp, frame2_sp;
stack_section
// frame 0
.Append(16, 0) // space
.D32(0x40090000) // junk that's not
.D32(0x60000000) // a return address
.D32(return_address1) // actual return address
// frame 1
.Mark(&frame1_sp)
.Append(16, 0) // space
.D32(0xF0000000) // more junk
.D32(0x0000000D)
.D32(return_address2) // actual return address
// frame 2
.Mark(&frame2_sp)
.Append(32, 0); // end of stack
RegionFromSection();
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510;
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value();
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules,
&frame_symbolizer);
Stackwalker::set_max_frames_scanned(0);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(1U, modules_without_symbols.size());
ASSERT_EQ("module1", modules_without_symbols[0]->debug_file());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(1U, frames->size());
StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0));
EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust);
ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity);
EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context)));
}
struct CFIFixture: public StackwalkerARMFixture {
CFIFixture() {
// Provide a bunch of STACK CFI records; we'll walk to the caller
// from every point in this series, expecting to find the same set
// of register values.
SetModuleSymbols(&module1,
// The youngest frame's function.
"FUNC 4000 1000 10 enchiridion\n"
// Initially, nothing has been pushed on the stack,
// and the return address is still in the link register.
"STACK CFI INIT 4000 100 .cfa: sp .ra: lr\n"
// Push r4, the frame pointer, and the link register.
"STACK CFI 4001 .cfa: sp 12 + r4: .cfa 12 - ^"
" r11: .cfa 8 - ^ .ra: .cfa 4 - ^\n"
// Save r4..r7 in r0..r3: verify that we populate
// the youngest frame with all the values we have.
"STACK CFI 4002 r4: r0 r5: r1 r6: r2 r7: r3\n"
// Restore r4..r7. Save the non-callee-saves register r1.
"STACK CFI 4003 .cfa: sp 16 + r1: .cfa 16 - ^"
" r4: r4 r5: r5 r6: r6 r7: r7\n"
// Move the .cfa back four bytes, to point at the return
// address, and restore the sp explicitly.
"STACK CFI 4005 .cfa: sp 12 + r1: .cfa 12 - ^"
" r11: .cfa 4 - ^ .ra: .cfa ^ sp: .cfa 4 +\n"
// Recover the PC explicitly from a new stack slot;
// provide garbage for the .ra.
"STACK CFI 4006 .cfa: sp 16 + pc: .cfa 16 - ^\n"
// The calling function.
"FUNC 5000 1000 10 epictetus\n"
// Mark it as end of stack.
"STACK CFI INIT 5000 1000 .cfa: 0 .ra: 0\n"
// A function whose CFI makes the stack pointer
// go backwards.
"FUNC 6000 1000 20 palinal\n"
"STACK CFI INIT 6000 1000 .cfa: sp 4 - .ra: lr\n"
// A function with CFI expressions that can't be
// evaluated.
"FUNC 7000 1000 20 rhetorical\n"
"STACK CFI INIT 7000 1000 .cfa: moot .ra: ambiguous\n");
// Provide some distinctive values for the caller's registers.
expected.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510;
expected.iregs[MD_CONTEXT_ARM_REG_SP] = 0x80000000;
expected.iregs[4] = 0xb5d55e68;
expected.iregs[5] = 0xebd134f3;
expected.iregs[6] = 0xa31e74bc;
expected.iregs[7] = 0x2dcb16b3;
expected.iregs[8] = 0x2ada2137;
expected.iregs[9] = 0xbbbb557d;
expected.iregs[10] = 0x48bf8ca7;
expected.iregs[MD_CONTEXT_ARM_REG_FP] = 0x8112e110;
// Expect CFI to recover all callee-saves registers. Since CFI is the
// only stack frame construction technique we have, aside from the
// context frame itself, there's no way for us to have a set of valid
// registers smaller than this.
expected_validity = (StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_SP |
StackFrameARM::CONTEXT_VALID_R4 |
StackFrameARM::CONTEXT_VALID_R5 |
StackFrameARM::CONTEXT_VALID_R6 |
StackFrameARM::CONTEXT_VALID_R7 |
StackFrameARM::CONTEXT_VALID_R8 |
StackFrameARM::CONTEXT_VALID_R9 |
StackFrameARM::CONTEXT_VALID_R10 |
StackFrameARM::CONTEXT_VALID_FP);
// By default, context frames provide all registers, as normal.
context_frame_validity = StackFrameARM::CONTEXT_VALID_ALL;
// By default, registers are unchanged.
raw_context = expected;
}
// Walk the stack, using stack_section as the contents of the stack
// and raw_context as the current register values. (Set the stack
// pointer to the stack's starting address.) Expect two stack
// frames; in the older frame, expect the callee-saves registers to
// have values matching those in 'expected'.
void CheckWalk() {
RegionFromSection();
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value();
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region,
&modules, &frame_symbolizer);
walker.SetContextFrameValidity(context_frame_validity);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(0U, modules_without_symbols.size());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(2U, frames->size());
StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0));
EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust);
ASSERT_EQ(context_frame_validity, frame0->context_validity);
EXPECT_EQ("enchiridion", frame0->function_name);
EXPECT_EQ(0x40004000U, frame0->function_base);
StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1));
EXPECT_EQ(StackFrame::FRAME_TRUST_CFI, frame1->trust);
ASSERT_EQ(expected_validity, frame1->context_validity);
if (expected_validity & StackFrameARM::CONTEXT_VALID_R1)
EXPECT_EQ(expected.iregs[1], frame1->context.iregs[1]);
if (expected_validity & StackFrameARM::CONTEXT_VALID_R4)
EXPECT_EQ(expected.iregs[4], frame1->context.iregs[4]);
if (expected_validity & StackFrameARM::CONTEXT_VALID_R5)
EXPECT_EQ(expected.iregs[5], frame1->context.iregs[5]);
if (expected_validity & StackFrameARM::CONTEXT_VALID_R6)
EXPECT_EQ(expected.iregs[6], frame1->context.iregs[6]);
if (expected_validity & StackFrameARM::CONTEXT_VALID_R7)
EXPECT_EQ(expected.iregs[7], frame1->context.iregs[7]);
if (expected_validity & StackFrameARM::CONTEXT_VALID_R8)
EXPECT_EQ(expected.iregs[8], frame1->context.iregs[8]);
if (expected_validity & StackFrameARM::CONTEXT_VALID_R9)
EXPECT_EQ(expected.iregs[9], frame1->context.iregs[9]);
if (expected_validity & StackFrameARM::CONTEXT_VALID_R10)
EXPECT_EQ(expected.iregs[10], frame1->context.iregs[10]);
if (expected_validity & StackFrameARM::CONTEXT_VALID_FP)
EXPECT_EQ(expected.iregs[MD_CONTEXT_ARM_REG_FP],
frame1->context.iregs[MD_CONTEXT_ARM_REG_FP]);
// We would never have gotten a frame in the first place if the SP
// and PC weren't valid or ->instruction weren't set.
EXPECT_EQ(expected.iregs[MD_CONTEXT_ARM_REG_SP],
frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]);
EXPECT_EQ(expected.iregs[MD_CONTEXT_ARM_REG_PC],
frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(expected.iregs[MD_CONTEXT_ARM_REG_PC],
frame1->instruction + 2);
EXPECT_EQ("epictetus", frame1->function_name);
}
// The values we expect to find for the caller's registers.
MDRawContextARM expected;
// The validity mask for expected.
int expected_validity;
// The validity mask to impose on the context frame.
int context_frame_validity;
};
class CFI: public CFIFixture, public Test { };
TEST_F(CFI, At4000) {
stack_section.start() = expected.iregs[MD_CONTEXT_ARM_REG_SP];
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004000;
raw_context.iregs[MD_CONTEXT_ARM_REG_LR] = 0x40005510;
CheckWalk();
}
TEST_F(CFI, At4001) {
Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP];
stack_section
.D32(0xb5d55e68) // saved r4
.D32(0x8112e110) // saved fp
.D32(0x40005510) // return address
.Mark(&frame1_sp); // This effectively sets stack_section.start().
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004001;
raw_context.iregs[4] = 0x635adc9f; // distinct callee r4
raw_context.iregs[MD_CONTEXT_ARM_REG_FP] = 0xbe145fc4; // distinct callee fp
CheckWalk();
}
// As above, but unwind from a context that has only the PC and SP.
TEST_F(CFI, At4001LimitedValidity) {
context_frame_validity =
StackFrameARM::CONTEXT_VALID_PC | StackFrameARM::CONTEXT_VALID_SP;
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004001;
raw_context.iregs[MD_CONTEXT_ARM_REG_FP] = 0xbe145fc4; // distinct callee fp
Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP];
stack_section
.D32(0xb5d55e68) // saved r4
.D32(0x8112e110) // saved fp
.D32(0x40005510) // return address
.Mark(&frame1_sp); // This effectively sets stack_section.start().
expected_validity = (StackFrameARM::CONTEXT_VALID_PC
| StackFrameARM::CONTEXT_VALID_SP
| StackFrameARM::CONTEXT_VALID_FP
| StackFrameARM::CONTEXT_VALID_R4);
CheckWalk();
}
TEST_F(CFI, At4002) {
Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP];
stack_section
.D32(0xfb81ff3d) // no longer saved r4
.D32(0x8112e110) // saved fp
.D32(0x40005510) // return address
.Mark(&frame1_sp); // This effectively sets stack_section.start().
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004002;
raw_context.iregs[0] = 0xb5d55e68; // saved r4
raw_context.iregs[1] = 0xebd134f3; // saved r5
raw_context.iregs[2] = 0xa31e74bc; // saved r6
raw_context.iregs[3] = 0x2dcb16b3; // saved r7
raw_context.iregs[4] = 0xfdd35466; // distinct callee r4
raw_context.iregs[5] = 0xf18c946c; // distinct callee r5
raw_context.iregs[6] = 0xac2079e8; // distinct callee r6
raw_context.iregs[7] = 0xa449829f; // distinct callee r7
raw_context.iregs[MD_CONTEXT_ARM_REG_FP] = 0xbe145fc4; // distinct callee fp
CheckWalk();
}
TEST_F(CFI, At4003) {
Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP];
stack_section
.D32(0x48c8dd5a) // saved r1 (even though it's not callee-saves)
.D32(0xcb78040e) // no longer saved r4
.D32(0x8112e110) // saved fp
.D32(0x40005510) // return address
.Mark(&frame1_sp); // This effectively sets stack_section.start().
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004003;
raw_context.iregs[1] = 0xfb756319; // distinct callee r1
raw_context.iregs[MD_CONTEXT_ARM_REG_FP] = 0x0a2857ea; // distinct callee fp
expected.iregs[1] = 0x48c8dd5a; // caller's r1
expected_validity |= StackFrameARM::CONTEXT_VALID_R1;
CheckWalk();
}
// We have no new rule at module offset 0x4004, so the results here should
// be the same as those at module offset 0x4003.
TEST_F(CFI, At4004) {
Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP];
stack_section
.D32(0x48c8dd5a) // saved r1 (even though it's not callee-saves)
.D32(0xcb78040e) // no longer saved r4
.D32(0x8112e110) // saved fp
.D32(0x40005510) // return address
.Mark(&frame1_sp); // This effectively sets stack_section.start().
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004004;
raw_context.iregs[1] = 0xfb756319; // distinct callee r1
expected.iregs[1] = 0x48c8dd5a; // caller's r1
expected_validity |= StackFrameARM::CONTEXT_VALID_R1;
CheckWalk();
}
// Here we move the .cfa, but provide an explicit rule to recover the SP,
// so again there should be no change in the registers recovered.
TEST_F(CFI, At4005) {
Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP];
stack_section
.D32(0x48c8dd5a) // saved r1 (even though it's not callee-saves)
.D32(0xf013f841) // no longer saved r4
.D32(0x8112e110) // saved fp
.D32(0x40005510) // return address
.Mark(&frame1_sp); // This effectively sets stack_section.start().
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004005;
raw_context.iregs[1] = 0xfb756319; // distinct callee r1
expected.iregs[1] = 0x48c8dd5a; // caller's r1
expected_validity |= StackFrameARM::CONTEXT_VALID_R1;
CheckWalk();
}
// Here we provide an explicit rule for the PC, and have the saved .ra be
// bogus.
TEST_F(CFI, At4006) {
Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP];
stack_section
.D32(0x40005510) // saved pc
.D32(0x48c8dd5a) // saved r1 (even though it's not callee-saves)
.D32(0xf013f841) // no longer saved r4
.D32(0x8112e110) // saved fp
.D32(0xf8d15783) // .ra rule recovers this, which is garbage
.Mark(&frame1_sp); // This effectively sets stack_section.start().
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004006;
raw_context.iregs[1] = 0xfb756319; // callee's r1, different from caller's
expected.iregs[1] = 0x48c8dd5a; // caller's r1
expected_validity |= StackFrameARM::CONTEXT_VALID_R1;
CheckWalk();
}
// Check that we reject rules that would cause the stack pointer to
// move in the wrong direction.
TEST_F(CFI, RejectBackwards) {
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40006000;
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = 0x80000000;
raw_context.iregs[MD_CONTEXT_ARM_REG_LR] = 0x40005510;
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules,
&frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(0U, modules_without_symbols.size());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(1U, frames->size());
}
// Check that we reject rules whose expressions' evaluation fails.
TEST_F(CFI, RejectBadExpressions) {
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40007000;
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = 0x80000000;
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules,
&frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(0U, modules_without_symbols.size());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(1U, frames->size());
}
class StackwalkerARMFixtureIOS : public StackwalkerARMFixture {
public:
StackwalkerARMFixtureIOS() {
// iOS_test is used instead of iOS because the stackwalker has a check to
// avoid using CFI for iOS dumps. This is a workaround for bad CFI being
// produced by dump_syms for iOS.
// https://bugs.chromium.org/p/google-breakpad/issues/detail?id=764
system_info.os = "iOS_test";
system_info.os_short = "ios_test";
}
};
class GetFramesByFramePointer: public StackwalkerARMFixtureIOS, public Test { };
TEST_F(GetFramesByFramePointer, OnlyFramePointer) {
stack_section.start() = 0x80000000;
uint32_t return_address1 = 0x50000100;
uint32_t return_address2 = 0x50000900;
Label frame1_sp, frame2_sp;
Label frame1_fp, frame2_fp;
stack_section
// frame 0
.Append(32, 0) // Whatever values on the stack.
.D32(0x0000000D) // junk that's not
.D32(0xF0000000) // a return address.
.Mark(&frame1_fp) // Next fp will point to the next value.
.D32(frame2_fp) // Save current frame pointer.
.D32(return_address2) // Save current link register.
.Mark(&frame1_sp)
// frame 1
.Append(32, 0) // Whatever values on the stack.
.D32(0x0000000D) // junk that's not
.D32(0xF0000000) // a return address.
.Mark(&frame2_fp)
.D32(0)
.D32(0)
.Mark(&frame2_sp)
// frame 2
.Append(32, 0) // Whatever values on the stack.
.D32(0x0000000D) // junk that's not
.D32(0xF0000000); // a return address.
RegionFromSection();
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510;
raw_context.iregs[MD_CONTEXT_ARM_REG_LR] = return_address1;
raw_context.iregs[MD_CONTEXT_ARM_REG_IOS_FP] = frame1_fp.Value();
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value();
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, MD_CONTEXT_ARM_REG_IOS_FP,
&stack_region, &modules, &frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(2U, modules_without_symbols.size());
ASSERT_EQ("module1", modules_without_symbols[0]->debug_file());
ASSERT_EQ("module2", modules_without_symbols[1]->debug_file());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(3U, frames->size());
StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0));
EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust);
ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity);
EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context)));
StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1));
EXPECT_EQ(StackFrame::FRAME_TRUST_FP, frame1->trust);
ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_LR |
StackFrameARM::RegisterValidFlag(MD_CONTEXT_ARM_REG_IOS_FP) |
StackFrameARM::CONTEXT_VALID_SP),
frame1->context_validity);
EXPECT_EQ(return_address1, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(return_address2, frame1->context.iregs[MD_CONTEXT_ARM_REG_LR]);
EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]);
EXPECT_EQ(frame2_fp.Value(),
frame1->context.iregs[MD_CONTEXT_ARM_REG_IOS_FP]);
StackFrameARM *frame2 = static_cast<StackFrameARM *>(frames->at(2));
EXPECT_EQ(StackFrame::FRAME_TRUST_FP, frame2->trust);
ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_LR |
StackFrameARM::RegisterValidFlag(MD_CONTEXT_ARM_REG_IOS_FP) |
StackFrameARM::CONTEXT_VALID_SP),
frame2->context_validity);
EXPECT_EQ(return_address2, frame2->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(0U, frame2->context.iregs[MD_CONTEXT_ARM_REG_LR]);
EXPECT_EQ(frame2_sp.Value(), frame2->context.iregs[MD_CONTEXT_ARM_REG_SP]);
EXPECT_EQ(0U, frame2->context.iregs[MD_CONTEXT_ARM_REG_IOS_FP]);
}
TEST_F(GetFramesByFramePointer, FramePointerAndCFI) {
// Provide the standatd STACK CFI records that is obtained when exmining an
// executable produced by XCode.
SetModuleSymbols(&module1,
// Adding a function in CFI.
"FUNC 4000 1000 10 enchiridion\n"
"STACK CFI INIT 4000 100 .cfa: sp 0 + .ra: lr\n"
"STACK CFI 4001 .cfa: sp 8 + .ra: .cfa -4 + ^"
" r7: .cfa -8 + ^\n"
"STACK CFI 4002 .cfa: r7 8 +\n"
);
stack_section.start() = 0x80000000;
uint32_t return_address1 = 0x40004010;
uint32_t return_address2 = 0x50000900;
Label frame1_sp, frame2_sp;
Label frame1_fp, frame2_fp;
stack_section
// frame 0
.Append(32, 0) // Whatever values on the stack.
.D32(0x0000000D) // junk that's not
.D32(0xF0000000) // a return address.
.Mark(&frame1_fp) // Next fp will point to the next value.
.D32(frame2_fp) // Save current frame pointer.
.D32(return_address2) // Save current link register.
.Mark(&frame1_sp)
// frame 1
.Append(32, 0) // Whatever values on the stack.
.D32(0x0000000D) // junk that's not
.D32(0xF0000000) // a return address.
.Mark(&frame2_fp)
.D32(0)
.D32(0)
.Mark(&frame2_sp)
// frame 2
.Append(32, 0) // Whatever values on the stack.
.D32(0x0000000D) // junk that's not
.D32(0xF0000000); // a return address.
RegionFromSection();
raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x50000400;
raw_context.iregs[MD_CONTEXT_ARM_REG_LR] = return_address1;
raw_context.iregs[MD_CONTEXT_ARM_REG_IOS_FP] = frame1_fp.Value();
raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value();
StackFrameSymbolizer frame_symbolizer(&supplier, &resolver);
StackwalkerARM walker(&system_info, &raw_context, MD_CONTEXT_ARM_REG_IOS_FP,
&stack_region, &modules, &frame_symbolizer);
vector<const CodeModule*> modules_without_symbols;
vector<const CodeModule*> modules_with_corrupt_symbols;
ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
&modules_with_corrupt_symbols));
ASSERT_EQ(1U, modules_without_symbols.size());
ASSERT_EQ("module2", modules_without_symbols[0]->debug_file());
ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
frames = call_stack.frames();
ASSERT_EQ(3U, frames->size());
StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0));
EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust);
ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity);
EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context)));
StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1));
EXPECT_EQ(StackFrame::FRAME_TRUST_FP, frame1->trust);
ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_LR |
StackFrameARM::RegisterValidFlag(MD_CONTEXT_ARM_REG_IOS_FP) |
StackFrameARM::CONTEXT_VALID_SP),
frame1->context_validity);
EXPECT_EQ(return_address1, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(return_address2, frame1->context.iregs[MD_CONTEXT_ARM_REG_LR]);
EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]);
EXPECT_EQ(frame2_fp.Value(),
frame1->context.iregs[MD_CONTEXT_ARM_REG_IOS_FP]);
EXPECT_EQ("enchiridion", frame1->function_name);
EXPECT_EQ(0x40004000U, frame1->function_base);
StackFrameARM *frame2 = static_cast<StackFrameARM *>(frames->at(2));
EXPECT_EQ(StackFrame::FRAME_TRUST_CFI, frame2->trust);
ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC |
StackFrameARM::CONTEXT_VALID_LR |
StackFrameARM::RegisterValidFlag(MD_CONTEXT_ARM_REG_IOS_FP) |
StackFrameARM::CONTEXT_VALID_SP),
frame2->context_validity);
EXPECT_EQ(return_address2, frame2->context.iregs[MD_CONTEXT_ARM_REG_PC]);
EXPECT_EQ(0U, frame2->context.iregs[MD_CONTEXT_ARM_REG_LR]);
EXPECT_EQ(frame2_sp.Value(), frame2->context.iregs[MD_CONTEXT_ARM_REG_SP]);
EXPECT_EQ(0U, frame2->context.iregs[MD_CONTEXT_ARM_REG_IOS_FP]);
}