Commit graph

1524 commits

Author SHA1 Message Date
Mark Mentovai
f5638b8c2e Test Gerrit
Change-Id: If335bec0a5079dececc0452b88a77d80f775ea97
Reviewed-on: https://chromium-review.googlesource.com/362660
Reviewed-by: Will Harris <wfh@chromium.org>
2016-07-25 13:44:49 +00:00
Aaron Gable
0e4af9d8f9 Add Breakpad codereview.settings entry for Gerrit
R=mark@chromium.org
BUG=629864

Review URL: https://codereview.chromium.org/2166193003 .
2016-07-21 12:45:20 -07:00
Mark Mentovai
5f638d5323 Remove DISALLOW_COPY_AND_ASSIGN from MinidumpStreamInfo
DISALLOW_COPY_AND_ASSIGN was inadvertently added to
Minidump::MinidumpStreamInfo in f04a010f71f6, but this class is used as
the value side of the Minidump::stream_map_ map and must be copyable
(with an old enough C++ library).

This broke:

https://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_chromeos_rel_ng/builds/247141/steps/compile%20%28with%20patch%29/logs/stdio

TBR=ivanpe@chromium.org

Review URL: https://codereview.chromium.org/2158423003 .
2016-07-20 10:08:14 -04:00
Ross McIlroy
b5200a97b7 Revert "Don't define |r_debug| and |link_map| on Android releases 21 and later"
This reverts commit 0fc10739232ac803f7304d01522db6051c7454ff.

Reason: breaks 64bit Android architectures.

BUG=629088
R=primiano@chromium.org

Review URL: https://codereview.chromium.org/2163923002 .
2016-07-20 11:27:11 +01:00
Will Harris
c99d374dde Add new exception code for OOM generated from Chromium.
See also https://codereview.chromium.org/2130293003/ for Chromium-side change and go/internal_cl_for_2130293003 for internal change.

BUG=chromium:614440
R=mark@chromium.org

Review URL: https://codereview.chromium.org/2160373002 .
2016-07-19 14:41:53 -07:00
Primiano Tucci
5adeef6117 Add process type to MicroDumpExtraInfo
BUG=616774
R=primiano@chromium.org, torne@chromium.org

Review URL: https://codereview.chromium.org/2087413002 .
2016-07-19 17:44:10 +01:00
Thomas Zimmermann
0ebdc4a10a Don't define |r_debug| and |link_map| on Android releases 21 and later
NDKs for Android 21 and later have the data structures |r_debug| and
|link_map| defined in their header files. Defining them multiple times
generates a compiler error.

This patch protects both data structures from definition on Android 21
and later.

BUG=629088
R=rmcilroy@chromium.org

Review URL: https://codereview.chromium.org/2156173002 .

Patch from Thomas Zimmermann <tzimmermann@mozilla.com>.
2016-07-19 17:00:51 +01:00
Ting-Yuan (Leo) Huang
41b91d064e Recover memory mappings before writing dump on ChromeOS
On Linux, breakpad relies on /proc/[pid]/maps to associate symbols from
addresses. ChromeOS' hugepage implementation replaces some segments
with anonymous private pages, which is a restriction of current
implementation in Linux kernel at the time of writing. Thus, breakpad
can no longer symbolize addresses from those text segments replaced by
hugepages.

This patch tries to recover the mappings. Because hugepages are always
inserted in between some .text sections, it tries to infer the names and
offsets of the segments, by looking at segments immediately precede and
succeed them.

For example, a text segment before hugepage optimization
  02001000-03002000 r-xp /opt/google/chrome/chrome

can be broken into
  02001000-02200000 r-xp /opt/google/chrome/chrome
  02200000-03000000 r-xp
  03000000-03002000 r-xp /opt/google/chrome/chrome

BUG=crbug.com/628040
R=mark@chromium.org

Review URL: https://codereview.chromium.org/2161713002 .

Patch from Ting-Yuan (Leo) Huang <laszio@chromium.org>.
2016-07-18 20:11:07 -04:00
John Budorick
965424f183 [Android] Guard some NDK workarounds by major version.
BUG=599327
R=mark@chromium.org

Review URL: https://codereview.chromium.org/2152153003 .
2016-07-15 12:49:44 -07:00
Ting-Yu Chou
dfd2da7979 Add a new argument to specify the minidump type to write on Windows.
R=ted.mielczarek@gmail.com
BUG=https://bugzilla.mozilla.org/show_bug.cgi?id=1267329

Review URL: https://codereview.chromium.org/2107083002/ .
2016-06-29 06:48:26 -04:00
Mike Frysinger
e0f2c17988 travis: note misbehavior by coverity addon when throttled
Example here: https://travis-ci.org/libgd/libgd/builds/139971212
The last line in the log is just the throttle notice.
2016-06-24 05:09:28 -04:00
Mike Frysinger
af8840d910 travis: move configure step to the prepare phase
The main command is more strict in that it has to be a single command.
2016-06-24 04:40:03 -04:00
Mike Frysinger
1600b6054e travis: make build scripts use bash
These are development scripts, so no need for them to be fast or
super portable.  Switch them to bash rather than POSIX shell.
2016-06-22 09:02:23 -04:00
Mike Frysinger
f140a0339f travis: fix cwd when running tests
Make sure we don't go messing with the cwd when running different tests.
This way we can always assume we start in the top level source dir.
2016-06-21 16:55:02 -04:00
Mike Frysinger
5325fd5162 travis: tweak coverity build command
The `build` shell func isn't in scope of the coverity shell script.
2016-06-21 15:10:31 -04:00
Mike Frysinger
83a5552060 travis: add coverity scan integration
R=ted.mielczarek@gmail.com

Review URL: https://codereview.chromium.org/2078283002 .
2016-06-21 11:14:28 -04:00
Ivan Penkov
24f5931c5e Server-side workaround to handle overlapping modules.
This change is resolving an issue that was caused by the combination of:
 - Android system libraries being relro packed in N+.
 - Breakpad dealing with relro packed libraries in a hack way.

This is a fix for http://crbug/611824.

I also found an use-after-free issue (bug in Minidump::SeekToStreamType).  I disallowed the MinidumpStreamInfo copy and assign constructors and the compiler detected another similar issue in Minidump::Print.  Then I disabled the copy and assign constructors for most classes in minidump.h (just in case).  There are a couple of classes where I couldn't disallow them (since assign is used).  This will require a small refactor so I left it out of this CL.

R=mark@chromium.org

Review URL: https://codereview.chromium.org/2060663002 .
2016-06-20 11:14:47 -07:00
Mike Frysinger
67f738b7ad linux-syscall-support: pull in latest version
The sys_mmap/sys_mmap2 weirdness has been cleaned up in lss now and there
is only one API now for everyone -- sys_mmap.

R=mseaborn@chromium.org

Review URL: https://codereview.chromium.org/2065493006 .
2016-06-14 14:17:56 -04:00
Ted Mielczarek
c44217f646 Dump INFO CODE_ID containing Build ID in Linux dump_syms
I'd like to have the Build ID available for our symbol server
uploading, and this will make it easy.

Most of this change is me rewriting dump_symbols_unittest to be
typed tests so I could add a new test there.

R=mark@chromium.org
BUG=

Review URL: https://codereview.chromium.org/2052263002 .
2016-06-10 13:23:29 -04:00
Nicholas Nethercote
7fc25b8962 Fix a trivial parsing bug caught by static analysis
R=ted
2016-06-10 09:51:14 -04:00
Ralph Giles
c65ed6573e Update symbol file documentation links.
These locations have changed since the move from Google Code.

R=ted.mielczarek@gmail.com
BUG=https://bugzilla.mozilla.org/show_bug.cgi?id=1275630
2016-06-10 06:29:06 -04:00
Primiano Tucci
a34c929f6f linux/android: add SIGTRAP to the list of signals handled by the client
__builtin_trap() causes a SIGTRAP on arm64 (at least with GCC 4.9).
SIGTRAP is not handled by breakpad, causing crashes induced by
__builtin_trap() to be missed.
Note that on x86 and arm, instead, __builtin_trap() raises a SIGILL,
which is already handled by breakapd.

BUG=chromium:614865
R=vapier@chromium.org

Review URL: https://codereview.chromium.org/2042853002 .
2016-06-08 17:04:49 +01:00
Primiano Tucci
72e94c4ddb [Android] Roll back to r10e.
BUG=599327
R=primiano@chromium.org
TBR=mark@chromium.org

Review URL: https://codereview.chromium.org/2042873003 .
2016-06-06 20:43:36 +01:00
Primiano Tucci
7933830cb7 [Android] Revert x86 workaround changes for NDK r11c.
BUG=599327
R=primiano@chromium.org
TBR=mark@chromium.org

Review URL: https://codereview.chromium.org/2035343002 .
2016-06-06 14:35:51 +01:00
Ivan Penkov
240ed57ee1 Adding support for overlapping ranges to RangeMap.
When enabled, adding of a new range that overlaps with an existing one can be a successful operation.  The range which ends at the higher address will be shrunk down by moving its start position to a higher address so that it does not overlap anymore.

This change is required to fix http://crbug/611824.  The actual fix will come in a separate CL.

R=mmandlis@chromium.org

Review URL: https://codereview.chromium.org/2029953003 .
2016-06-05 22:41:10 -07:00
Ted Mielczarek
8b7b28663f Make the getting started section in the README better
Some of my colleagues have commented in the past few months that the
Breakpad README is not very clear on how to get and build the code
nowadays. This change moves some of the docs from the "request
change review" section up to the "getting started" section, and adds
a few more things to clarify.

R=vapier@chromium.org
BUG=

Review URL: https://codereview.chromium.org/2035103002 .
2016-06-03 13:32:14 -04:00
Primiano Tucci
d269bd0f29 [Android] Update breakpad to NDK r11c.
BUG=599327
R=mark@chromium.org, primiano@chromium.org

Review URL: https://codereview.chromium.org/2025923003 .
2016-06-02 17:07:07 +01:00
Mike Frysinger
bad9e55ea5 fix signed warning errors in unittests
A bunch of gtest assert statements fail due to signed warnings as
unadorned constants are treated as signed integers.  Mark them all
unsigned to avoid that.

One example (focus on the "[with ...]" blocks that show the types):
In file included from src/breakpad_googletest_includes.h:33:0,
                 from src/common/memory_unittest.cc:30:
src/testing/gtest/include/gtest/gtest.h: In instantiation of 'testing::AssertionResult testing::internal::CmpHelperEQ(const char*, const char*, const T1&, const T2&) [with T1 = int; T2 = long unsigned int]':
src/testing/gtest/include/gtest/gtest.h:1524:23: required from 'static testing::AssertionResult testing::internal::EqHelper<true>::Compare(const char*, const char*, const T1&, const T2&, typename testing::internal::EnableIf<(! testing::internal::is_pointer<T2>::value)>::type*) [with T1 = int; T2 = long unsigned int; typename testing::internal::EnableIf<(! testing::internal::is_pointer<T2>::value)>::type = void]'
src/common/memory_unittest.cc:41:246: required from here
src/testing/gtest/include/gtest/gtest.h:1448:16: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
   if (expected == actual) {
                ^
cc1plus: some warnings being treated as errors
Makefile:5180: recipe for target 'src/common/src_client_linux_linux_client_unittest_shlib-memory_unittest.o' failed
make[2]: *** [src/common/src_client_linux_linux_client_unittest_shlib-memory_unittest.o] Error 1

R=ted.mielczarek@gmail.com

Review URL: https://codereview.chromium.org/2013893003 .
2016-05-26 10:09:46 -04:00
Mike Frysinger
6368037ef2 elf_reader: drop unused zlib include
This breaks building for targets that don't include zlib.

BUG=chromium:604440
R=ivanpe@chromium.org

Review URL: https://codereview.chromium.org/2010803003 .
2016-05-25 16:38:04 -04:00
Mike Frysinger
983d04d36e travis: verify out-of-tree builds & dist targets
Required updating a lot of dist files in the process.

R=ted.mielczarek@gmail.com

Review URL: https://codereview.chromium.org/1946293002 .
2016-05-25 14:36:37 -04:00
Veljko Mihailovic
71a5ee37a5 [MIPS] Rename variable mips to mips32
Renaming variable mips to mips32 since mips is already defined
by the toolchain.

BUG=Compile error in Chromium
R=mark@chromium.org

Review URL: https://codereview.chromium.org/2006393004 .

Patch from Veljko Mihailovic <veljko.mihailovic@imgtec.com>.
2016-05-25 10:13:18 -04:00
Ivan Penkov
79901bb99d Fixing an unused-variable warning in microdump_writer.cc
BUG=https://bugs.chromium.org/p/google-breakpad/issues/detail?id=699
R=mark@chromium.org, primiano@chromium.org

Review URL: https://codereview.chromium.org/2006333002 .
2016-05-24 12:08:25 -07:00
Lars Volker
f25a411200 Fix stack collection with size limit
src/client/linux/minidump_writer/minidump_writer.cc:273 obtains the
stack info by calling GetStackInfo(). That method will return the
stack base address, aligned to the bottom of the memory page that
'stack_pointer' is in. After that it will cap the size of the memory
area to be copied into the minidump to 'max_stack_len', starting from
the base address, if the caller requested so. This will be the case
when collecting reduced stacks, as introduced by this change:
https://breakpad.appspot.com/487002/

In such cases the caller will request 2048 bytes of memory. However
GetStackInfo() will have aligned the base address to the page
boundary, by default 4096 bytes. If the stack, which grows towards the
base address from the top ends before the 2048 bytes of the first
block, then we will not collect any useful part of the stack.

As a fix we skip chunks of 'max_stack_len' bytes starting from
the base address until the stack_pointer is actually contained in the
chunk, which we will add to the minidump file.

BUG=https://bugs.chromium.org/p/google-breakpad/issues/detail?id=695
R=ivanpe@chromium.org

Review URL: https://codereview.chromium.org/1959643004 .

Patch from Lars Volker <lv@cloudera.com>.
2016-05-24 11:49:35 -07:00
Tobias Sargeant
faeb1f9b2b Functions only called by DumpFreeSpace need to be conditionally compiled.
BUG=525938
R=mark@chromium.org

Review URL: https://codereview.chromium.org/2008553002 .
2016-05-23 18:58:48 +01:00
Primiano Tucci
adca10c8ff Add statistics about free space to microdump format.
When a crash occurs as a result of an allocation failure, it is useful
to know approximately what regions of the virtual address space remain
available, so that we know whether the crash should be attributed to
memory fragmentation, or some other cause.

BUG=525938
R=primiano@chromium.org

Review URL: https://codereview.chromium.org/1796803003 .
2016-05-23 16:06:26 +01:00
Yunlian Jiang
e35167de75 use another elf.h inside the package for common/dwarf/elf_reader
We tried to use common/android/include/elf.h, however it contains
'#include-next elf.h' so it still breaks MAC build. So we use
third_party/musl/include/elf.h instead.

BUG=none
TEST=make; make test passes. There is no '#include-next elf.h' in
     the new elf.h

R=michaelbai@chromium.org

Review URL: https://codereview.chromium.org/1994633003 .
2016-05-18 15:06:38 -07:00
Yunlian Jiang
9eb2c6fe6c Use elf.h inside the package.
MAC does not have elf.h, so use the elf.h inside the package instead
of the one in the system.
One failure example is
https://codereview.chromium.org/1978803003/

TEST=make; make check
BUG=
R=michaelbai@chromium.org

Review URL: https://codereview.chromium.org/1984713002 .
2016-05-18 12:56:22 -07:00
Ted Mielczarek
67d5567177 Don't let PDBSourceLineWriter::GetSymbolFunctionName return empty function names
It's possible for `IDiaSymbol::get_name` to return S_OK and provide
and empty string. I haven't figured out the exact root cause yet
(the symbols in question are coming from the Rust standard library),
but FUNC lines with missing function names break the processor and
so we should never do it. This change makes it output "<name omitted>"
which matches the behavior of the DWARF dumping code.

R=mark@chromium.org
BUG=https://bugzilla.mozilla.org/show_bug.cgi?id=1272278

Review URL: https://codereview.chromium.org/1985643004 .
2016-05-16 12:30:59 -04:00
Tao Bai
a875991e73 Revert "Write adjusted range back to module"
This is no right fix, we shouldn't allow module overlap.

This reverts commit 4f417c8c0f.

BUG=606972
R=mark@chromium.org

Review URL: https://codereview.chromium.org/1976683004 .

Patch from Tao Bai <michaelbai@chromium.org>.
2016-05-13 12:45:44 -04:00
Dave MacLachlan
a84d4fc426 Replaced glibc version of elf.h with musl version of elf.h.
Updated dump_syms xcode project and ran tests.

BUG=
R=vapier@chromium.org

Review URL: https://codereview.chromium.org/1973113002 .
2016-05-12 14:22:59 -07:00
Dave MacLachlan
3d225e288c Fixes up dump_syms build on OS X so it works with ELF.
Adds elf.h header from glibc.
Updates dwarf2reader.cc so it isn't comparing a unique_ptr against NULL.
Moves from MacOS10.5 SDK to latest SDK for Xcode project.
Moves from using gcc to clang for dump_syms tests.
Disables warning about 'Missing Field In Structure Initializers' to temporarily work around https://bugs.chromium.org/p/google-breakpad/issues/detail?id=697.

With this patch all tests form dump_syms pass again using Xcode 7.3 on Mac OS X 10.11.

BUG= https://bugs.chromium.org/p/google-breakpad/issues/detail?id=696, https://bugs.chromium.org/p/google-breakpad/issues/detail?id=697
R=mark@chromium.org

Review URL: https://codereview.chromium.org/1970903002 .
2016-05-12 11:38:09 -07:00
Dave MacLachlan
1bbe2f29c9 Update to handle dsym files that end with a header.
dsym files generated by Xcode for swift (Xcode 7.3) end with a header, and the
code did not handle that case.

BUG=https://bugs.chromium.org/p/google-breakpad/issues/detail?id=689
R=ivanpe@chromium.org

Review URL: https://codereview.chromium.org/1971793002 .
2016-05-11 14:10:23 -07:00
Yunlian Jiang
638066b82e breakpad: fix unittest errors
This fixes the unittest error caused by
https://codereview.chromium.org/1884283002/

TEST=unittest passes on falco board in ChromeOS.
BUG=
R=vapier@chromium.org

Review URL: https://codereview.chromium.org/1952083002 .
2016-05-04 16:48:00 -07:00
Yunlian Jiang
764c21f752 Add debug fission support.
This added debug fission support.
It tries to find the dwp file from the debug dir /usr/lib/debug/*/debug
and read symbols from them.

Most of this patch comes from
https://critique.corp.google.com/#review/52048295
and some fixes after that.
The elf_reader.cc comes from TOT google code. I just
removed some google dependency.

Current problems from this patch
1: Some type mismatch: from uint8_t * to char *.
2: Some hack to find the .dwp file. (replace .debug with .dwp)

BUG=chromium:604440
R=dehao@google.com, ivanpe@chromium.org

Review URL: https://codereview.chromium.org/1884283002 .
2016-05-04 11:09:44 -07:00
Mike Frysinger
b5712766f6 macho: fix printf type mismatches
The %ld expects a long signed integer, but we're passing in a size_t.
Use %zu which is an unsigned size_t type.

R=ted.mielczarek@gmail.com

Review URL: https://codereview.chromium.org/1951603002 .
2016-05-04 13:20:27 -04:00
Tao Bai
4f417c8c0f Write adjusted range back to module
In Android, the mmap could be overlapped by /dev/ashmem, we adjusted
the range in https://breakpad.appspot.com/9744002/, but adjusted
range isn't written back to module, this caused the corresponding
module be dropped in BasicCodeModules copy constructor.

This also fix a lot of 'unable to store module' warnings
when dumping Android's minidump.

BUG=606972
R=mark@chromium.org, wfh@chromium.org

Review URL: https://codereview.chromium.org/1939333002 .

Patch from Tao Bai <michaelbai@chromium.org>.
2016-05-03 18:14:28 -04:00
Primiano Tucci
fcb844ee32 Add parentheses to silence clang warning
crrev.com/1887033002 introuced a clang warning (see below).
This fixes it, so that breakpad can be rolled in chrome, where
warnings are always fatal.

From: https://build.chromium.org/p/tryserver.chromium.android/builders/android_chromium_gn_compile_dbg/builds/59031/steps/compile%20%28with%20patch%29/logs/stdio

FAILED: clang_x64/obj/breakpad/dump_syms/dwarf_cu_to_module.o
../../breakpad/src/common/dwarf_cu_to_module.cc:420:20: error: '&&' within '||' [-Werror,-Wlogical-op-parentheses]
if (declaration_ && qualified_name || (unqualified_name && enclosing_name)) {
~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~ ~~
../../breakpad/src/common/dwarf_cu_to_module.cc:420:20: note: place parentheses around the '&&' expression to silence this warning
if (declaration_ && qualified_name || (unqualified_name && enclosing_name)) {
                 ^
   (                             )

R=mark@chromium.org, petrcermak@chromium.org

Review URL: https://codereview.chromium.org/1928363002 .
2016-05-03 16:56:06 +02:00
Primiano Tucci
17ad0c18b1 Revert of Extend mapping merge to include reserved but unused mappings. (https://breakpad.appspot.com/7714003)
Reason for revert:
It is causing breakpad crash reports to be invalid (see the associated
bug).

Merging empty holes in r-x mappings was originally introduced in
https://breakpad.appspot.com/7714003 to deal with the first generation
of relro packing, which could introduce holes within a .so mapping:

  [libchrome.so]
  [guard region]
  [libchrome.so]

However, the logic is broken for the case of two *different* adjacent
.so mappings with a guard region in the middle:

  [libfoo.so]
  [guard region]
  [libchrome.so]

In this case the guard region is mistakenly associated with libfoo.so,
but that is not the right thing to do. In fact, the second generation of
rerlo packing added the guard region to prevent mmaps from overlapping
and to give room for the non-zero vaddr of relro-packed libraries, which
require an anticipated load bias.

As the first generation of relro packing is not used anymore, there is
no reason to keep this buggy code, which causes failures in decoding
crashes where an arbitrary library is mapped immediately before a rerlo
packed library.

Original issue's description:
> Extend mapping merge to include reserved but unused mappings.
>
> When parsing /proc/pid/maps, current code merges adjacent entries that
> refer to the same library and where the start of the second is equal to
> the end of the first, for example:
>
>   40022000-40025000 r-xp 00000000 b3:11 827        /system/lib/liblog.so
>   40025000-40026000 r--p 00002000 b3:11 827        /system/lib/liblog.so
>   40026000-40027000 rw-p 00003000 b3:11 827        /system/lib/liblog.so
>
> When the system linker loads a library it first reserves all the address
> space required, from the smallest start to the largest end address, using
> an anonymous mapping, and then maps loaded segments inside that reservation.
> If the loaded segments do not fully occupy the reservation this leaves
> gaps, and these gaps prevent merges that should occur from occurring:
>
>   40417000-4044a000 r-xp 00000000 b3:11 820        /system/lib/libjpeg.so
> > 4044a000-4044b000 ---p 00000000 00:00 0
>   4044b000-4044c000 r--p 00033000 b3:11 820        /system/lib/libjpeg.so
>   4044c000-4044d000 rw-p 00034000 b3:11 820        /system/lib/libjpeg.so
>
> Where the segments that follow this gap do not contain executable code
> the failure to merge does not affect breakpad operation.  However, where
> they do then the merge needs to occur.  Packing relocations in a large
> library splits the executable segment into two, resulting in:
>
>   73b0c000-73b21000 r-xp 00000000 b3:19 786460
> /data/.../libchrome.2160.0.so
> > 73b21000-73d12000 ---p 00000000 00:00 0
>   73d12000-75a90000 r-xp 00014000 b3:19 786460
> /data/.../libchrome.2160.0.so
>   75a90000-75c0d000 rw-p 01d91000 b3:19 786460
> /data/.../libchrome.2160.0.so
>
> Here the mapping at 73d12000-75a90000 must be merged into 73b0c000-73b21000
> so that breakpad correctly calculates the base address for text.
>
> This change enables the full merge by also merging anonymous maps which
> result from unused reservation, identified as '---p' with offset 0, and
> which follow on from an executable mapping, into that executable mapping.
>
> BUG=chromium:394703

BUG=chromium:499747
R=primiano@chromium.org, rmcilroy@chromium.org

Review URL: https://codereview.chromium.org/1923383002 .
2016-04-28 16:49:44 +01:00
Dave MacLachlan
8762c82297 Remove GTM_ENABLE_LEAKS and GTMGarbageCollection
Removes some archaic Google Toolbox For Mac features.

BUG=
R=ivanpe@chromium.org, mark@chromium.org

Review URL: https://codereview.chromium.org/1912473002 .
2016-04-21 13:20:17 -07:00
Ted Mielczarek
ea2e22b352 Make x86-64 frame pointer unwinding stricter
The x86-64 frame pointer-based unwind method will accept values
that aren't valid for the frame pointer register and the return address.
This fixes it to reject non-8-byte-aligned frame pointers, as
well as non-canonical addresses for the return address it finds.

A colleague of mine asked me why Breakpad gave a bad stack
for a crash in our crash-stats system:
https://crash-stats.mozilla.com/report/index/a472c842-2c7b-4ca7-a267-478cf2160405

Digging in, it turns out that the function in frame 0 is a leaf function,
so MSVC doesn't generate an entry in the unwind table for it, so
dump_syms doesn't produce a STACK CFI entry for it in the symbol file.
The stackwalker tries frame pointer unwinding, and %rbp is set to a
value that sort-of works, so it produces a garbage frame 1 and then
is lost. Either of the two checks in this patch would have stopped
the stackwalker from using the frame pointer.

It's possible we could do something smarter on the dump_syms side,
like enumerating all functions and outputing some default STACK CFI rule
for those that don't have unwind info, but that wouldn't fix crashes
from existing builds without re-dumping symbols for them. In any event,
these checks should always pass for valid frame pointer-using functions.

R=mark@chromium.org
BUG=https://bugzilla.mozilla.org/show_bug.cgi?id=1263001

Review URL: https://codereview.chromium.org/1902783002 .
2016-04-19 15:20:09 -04:00