| Commit message (Collapse) | Author | Age | Files | Lines |
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Depending on compiler's setting, the unreferenced local variable may
cause build break.
modified: src/processor/minidump.cc
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1866533002 .
Patch from Yunxiao Ma <yxma@google.com>.
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Some projects will get build break because the comipler is confused when
searches for the standard stdio.h. Rename the wrapper file to avoid that.
renamed: src/common/stdio.h -> src/common/stdio_wrapper.h
modified: src/processor/minidump.cc
modified: src/processor/dump_context.cc
modified: src/processor/logging.cc
modified: src/processor/minidump.cc
modified: src/processor/minidump_processor.cc
modified: src/processor/stackwalk_common.cc
modified: src/processor/symbolic_constants_win.cc
R=mark@chromium.org, labath@google.com
Review URL: https://codereview.chromium.org/1864603002 .
Patch from Yunxiao Ma <yxma@google.com>.
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This preserves full build ids in minidumps, which are useful for
tracking down the right version of system libraries from Linux
distributions.
The default build id produced by GNU binutils' ld is a 160-bit SHA-1
hash of some parts of the binary, which is exactly 20 bytes:
https://sourceware.org/binutils/docs-2.26/ld/Options.html#index-g_t_002d_002dbuild_002did-292
The bulk of the changes here are to change the signatures of the
FileID methods to use a wasteful_vector instead of raw pointers, since
build ids can be of arbitrary length.
The previous change that added support for this in the processor code
preserved the return value of `Minidump::debug_identifier()` as the
current `GUID+age` treatment for backwards-compatibility, and exposed
the full build id from `Minidump::code_identifier()`, which was
previously stubbed out for Linux dumps. This change keeps the debug ID
in the `dump_syms` output the same to match.
R=mark@chromium.org, thestig@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1688743002 .
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Based on changes for ARM, ARM64 and X86, the support for
MIPS and MIPS64 is added in microdump.
TEST=microdump_stackwalk ~/microdump-mips32.dmp symbols/
BUG=microdump_stackwalk failing for mips architectures
Review URL: https://codereview.chromium.org/1731923002/
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R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1849933002 .
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Currently EXC_BAD_ACCESS doesn't support EXC_I386_GPFLT as
exception_flags for pretty-printing in the processor, but this happens
for a lot of things:
http://opensource.apple.com/source/xnu/xnu-2050.24.15/osfmk/i386/trap.c
(search for EXC_I386_GPFLT).
And we get a lot of these in the wild:
https://crash-stats.mozilla.com/search/?reason=%3DEXC_BAD_ACCESS+%2F+0x0000000d&cpu_name=amd64&_facets=signature&_facets=address&_columns=date&_columns=signature&_columns=product&_columns=version&_columns=build_id&_columns=platform&_columns=address#crash-reports
This patch makes them show up with a nice name instead of the current
"EXC_BAD_ACCESS / 0x0000000d".
Additionally, this patch fixes some other cases where x86-64 wasn't being handled in the same way as x86, and fixes some x86-specific exception flags to be stringified with I386 in the output.
R=mark@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1833123002 .
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behavior under sized-delete.
The code as it stands allocates a chunk of memory of arbitrary size and places an object into it. It stores a pointer to that object and memory into a list telling the compiler that it is a pointer to a char. When the compiler deletes the objects in the list it thinks that the list contains pointers to chars - not pointers to arbitrarily sized regions of memory.
This is fixing an issue that will reproduces when the following optimization (C++ sized dealocation) is enabled: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3536.html
The fix is to explicitly call the non-sized delete operator, and the library code that supports malloc/free/new/delete will figure out the size of the block of memory from the pointer being passed in.
Patch provided by Darryl Gove.
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1788473002 .
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Properly handle microdump processing, when the system_log file contains an incomplete microdump section at the top. The processor will process the first complete microdump section.
R=primiano@chromium.org
Review URL: https://codereview.chromium.org/1742843002 .
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BUG=587536
R=primiano@chromium.org
Review URL: https://codereview.chromium.org/1704243002 .
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BUG=https://code.google.com/p/chromium/issues/detail?id=584174
R=mmandlis@chromium.org
Review URL: https://codereview.chromium.org/1697963002 .
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GPU infromation in the following format:
G GL_VERSION|GL_VENDOR|GL_RENDERER.
The GPU version, vendor and renderer are extracted during microdump parsing and populated in the appropriate fields in the SystemInfo struct.
This is to match the changes introduced in crrev.com/1343713002 and crrev.com/1334473003
BUG=chromium:536769
R=primiano@chromium.org
Review URL: https://codereview.chromium.org/1678463002 .
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This reverts commit cb936a0243c97ae9cd2d4bb19d95dde0421fed6d.
A=dyen@chromium.org
Original Review: https://codereview.chromium.org/1672773002/
R=dyen@chromium.org
Review URL: https://codereview.chromium.org/1688493003 .
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This patch changes MDCVInfoELF (which is currently unused, apparently
a vestigal bit of code landed as part of Solaris support) into a supported
CodeView format that simply contains a build id as raw bytes.
Modern ELF toolchains support build ids nicely:
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Developer_Guide/compiling-build-id.html
It would be useful to have the original build ids of loaded modules in
Linux minidumps, since tools like Fedora's darkserver allow querying by build
id and the current Breakpad code truncates the build id to the size of a GUID,
which loses information:
https://darkserver.fedoraproject.org/
A follow-up patch will change the Linux minidump generation code to produce
MDCVInfoELF in minidumps instead of MDCVInfoPDB70. This patch should be landed
first to ensure that crash processors are able to handle this format before
dumps are generated containing it.
The full build id is exposed as the return value of Minidump::code_identifier(),
which currently just returns "id" for modules in Linux dumps. For
backwards-compatibility, Minidump::debug_identifier() continues to treat
the build id as a GUID, so debug identifiers for existing modules will not
change.
BUG=
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1675413002 .
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Adding remaining mips n64 support including stackwalker.
BUG=None
TEST=manually tested on Linux/Android
R=vapier@chromium.org
Review URL: https://codereview.chromium.org/1418453011 .
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In order to figure out what symbols we need associated to a minidump,
it is useful to be able to dump all the modules the minidump contains.
A=dyen@chromium.org
Original Review: https://codereview.chromium.org/1651593002/
BUG=563716
R=dyen@chromium.org
Review URL: https://codereview.chromium.org/1650713002 .
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This updates the GYP build for the processor component (on windows).
- adds/removes references to files which were added or removed from the
repository
- includes build/common.gypi in the gyp files: needed to correctly
detect the OS (I think, the generated MSVC solutions were broken
without it)
- conditionally compiles code platform-specific code for the given
platform
After this minidump processor nearly compiles with VS2013: the generated
project is correct, but some files still have compilation errors.
Disclaimer: I have not tested the GYP changes on non-windows platform,
as there does not seem to be anyone using it there.
BUG=
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1643633004 .
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The std::getline function always returns its first arg (which is an
iostream object) and cannot return anything else. Thus, testing its
value is pointless, and even leads to build errors w/at least gcc-5
due to gtest ASSERT_TRUE funcs only taking bool types:
.../exploitability_unittest.cc: In member function 'virtual void {anonymous}::ExploitabilityLinuxUtilsTest_DisassembleBytesTest_Test::TestBody()':
.../exploitability_unittest.cc:200:136: error: no matching function for call to 'testing::AssertionResult::AssertionResult(std::basic_istream<char>&)'
In file included from .../breakpad_googletest_includes.h:33:0,
from .../exploitability_unittest.cc:35:
.../gtest.h:262:12: note: candidate: testing::AssertionResult::AssertionResult(bool)
Since we know this never fails, simply drop the ASSERT_TRUE usage.
The next line already checks the content of the buffer we read.
Further on in the file, we hit some signed warnings:
In file included from .../breakpad_googletest_includes.h:33:0,
from .../exploitability_unittest.cc:35:
.../gtest.h: In instantiation of 'testing::AssertionResult testing::internal::CmpHelperEQ(const char*, const char*, const T1&, const T2&) [with T1 = long unsigned int; T2 = int]':
.../gtest.h:1484:23: required from 'static testing::AssertionResult testing::internal::EqHelper<lhs_is_null_literal>::Compare(const char*, const char*, const T1&, const T2&) [with T1 = long unsigned int; T2 = int; bool lhs_is_null_literal = false]'
.../exploitability_unittest.cc:241:289: required from here
.../gtest.h:1448:16: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
if (expected == actual) {
This is because we compare the register value (a uint64_t) directly to
an integer constant, and those are signed by default. Stick a U suffix
on them to fix things up.
BUG=chromium:579384
TEST=`make check` passes
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1611763002 .
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Older versions of MSVC don't have a snprintf functions. Some files
were already working around that, but not all of them. Instead of
copying the logic into every file, I centralize it into a new
stdio.h wrapper file and make other files include that.
BUG=
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1602563003 .
Patch from Pavel Labath <labath@google.com>.
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In C/C++, the result of signed integer overflow is undefined.
The expression "base + size - 1" is parsed as "(base + size) - 1", and
"base + size" can overflow even if "base + (size - 1)" <= INT_MAX.
See http://g/c-compiler-chrome/461JohPKakE/JI3rEBg6FwAJ for more.
BUG=None
TEST='CC=clang CXX=clang++ ./configure && make check'
R=vapier@chromium.org
Review URL: https://codereview.chromium.org/1591793002 .
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This file is not present on windows, and it's causing build errors
there. As far as I can tell, nothing in this file actually uses
that include, so I just remove it.
BUG=
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1475353002 .
Patch from Pavel Labath <labath@google.com>.
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A=thakis@chromium.org
Original Review: https://codereview.chromium.org/1550933002/
R=thakis@chromium.org
Review URL: https://codereview.chromium.org/1554613002 .
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file ends with 0
R=ivanpe@chromium.org
BUG=https://bugs.chromium.org/p/google-breakpad/issues/detail?id=668
Review URL: https://codereview.chromium.org/1482363003 .
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There is an issue in StackwalkerAMD64::GetCallerByFramePointerRecovery.
Occasionally it produces invalid frames (instruction pointer == 0) which
prevents the AMD64 stack walker from proceeding to do stack scanning and
instead leads to premature termination of the stack walking process.
For more details: http://crbug/537444
BUG=
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1408973002 .
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than 2013.
The Windows client gyp files were missing proc_maps_linux.cc for the
unittest build. Adding that revealed some build errors due to it
unconditionally including <inttypes.h>. Removing the workarounds in
breakpad_types.h (and a few other places) made that build, which means
that Visual C++ 2013 is now our minimum supported version of MSVC.
Additionally I tried building with VC++ 2015 and fixed a few warnings
(which were failing the build because we have /WX enabled) to ensure
that that builds as well.
BUG=https://code.google.com/p/google-breakpad/issues/detail?id=669
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1353893002 .
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Chrome started hitting some crashes in v8 jitted code which happens to be
non ABI compliant and debuggers (including WinDBG) are unable to produce
meaningful stack traces.
The Breakpad stack walker has some builtin heuristics to deal with such cases.
More specifically, when unable to find a good parent frame, it scans the raw
stack to find a suitable parent frame. The max scan size was set at 30
pointers which was (apparently) not enough to recover in this case.
I'm increasing it to 40 pointers. I confirmed that at 34 pointers it was able
to recover however I'm setting it to 40 in order to it some slack.
I needed to update two unittests which were expecting the previous scan limit.
BUG=
R=mark@chromium.org
Review URL: https://codereview.chromium.org/1379433005 .
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the microdump. The microdump OS/arch line looks like:
O A arm 04 armv7l 3.4.0-perf-g4d6e88e #1 SMP PREEMPT Mon Mar 30 19:09:30 2015
and currently the field that says "armv7l" or "aarch64" is being used
to fill in the CPU arch field in crash. The problem is that on a
64-bit device this field *always* says "aarch64" even when running in
a 32-bit process, and so currently the crash reports for aarch64 are
a mix of 32-bit and 64-bit crashes. We should be using the first field
instead, which just says "arm" or "arm64" and reflects the actual
version of webview (32-bit or 64-bit) which is running.
BUG=
R=primiano@chromium.org
Review URL: https://codereview.chromium.org/1306983003 .
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1498 4c0a9323-5329-0410-9bdc-e9ce6186880e
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If a crash occurred as a result to a write to unwritable memory, it is reason
to suggest exploitability. The processor checks for a bad write by
disassembling the command that caused the crash by piping the raw bytes near
the instruction pointer through objdump. This allows the processor to see if
the instruction that caused the crash is a write to memory and where the
target of the address is located.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1273823004
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1497 4c0a9323-5329-0410-9bdc-e9ce6186880e
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R=ivanpe at https://codereview.chromium.org/1292503005/
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1496 4c0a9323-5329-0410-9bdc-e9ce6186880e
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crrev.com/1298443002 has introduced a build failure by re-defining
__STDC_FORMAT_MACROS. Fixing it.
BUG=
R=mark@chromium.org, ted.mielczarek@gmail.com
Review URL: https://codereview.chromium.org/1303493003 .
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1493 4c0a9323-5329-0410-9bdc-e9ce6186880e
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R=ivanpe at https://codereview.chromium.org/1298443002/
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1491 4c0a9323-5329-0410-9bdc-e9ce6186880e
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This CL also consequentially adds a public method to get the number of
mappings in a Linux minidump.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1291603002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1488 4c0a9323-5329-0410-9bdc-e9ce6186880e
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mappings when rating Linux exploitability.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1286033002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1487 4c0a9323-5329-0410-9bdc-e9ce6186880e
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R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1288323003
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1486 4c0a9323-5329-0410-9bdc-e9ce6186880e
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git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1485 4c0a9323-5329-0410-9bdc-e9ce6186880e
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R=lei at https://codereview.chromium.org/1211963002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1484 4c0a9323-5329-0410-9bdc-e9ce6186880e
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R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1280853003
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1483 4c0a9323-5329-0410-9bdc-e9ce6186880e
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MinidumpLinuxMapsList.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1287803002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1482 4c0a9323-5329-0410-9bdc-e9ce6186880e
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contents of /proc/<pid>/maps instead of just the files mapped to memory.
Review URL: https://codereview.chromium.org/1273123002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1481 4c0a9323-5329-0410-9bdc-e9ce6186880e
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If there is a range overlap, the cause may be the client correction applied for Android packed relocations. If this is the case, back out the client correction and retry.
Patch from Simon Baldwin <simonb@chromium.org>.
https://code.google.com/p/chromium/issues/detail?id=509110
R=simonb@chromium.org
Review URL: https://codereview.chromium.org/1275173005
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1480 4c0a9323-5329-0410-9bdc-e9ce6186880e
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If a MinidumpLinuxMapsList was created and destroyed without its Read method,
the program would have a segmentation fault because the destructor did not
check for a null maps_ field. Additional changes include additional
supplementary null checks, a potential memory leak fix, and some comment
removal.
Review URL: https://codereview.chromium.org/1271543002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1478 4c0a9323-5329-0410-9bdc-e9ce6186880e
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Review URL: https://codereview.chromium.org/1266493002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1477 4c0a9323-5329-0410-9bdc-e9ce6186880e
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when checking exploitability rating.
Linux minidumps do not support MD_MEMORY_INFO_LIST_STREAM, meaning the
processor cannot retrieve its memory mappings. However, it has its own
stream, MD_LINUX_MAPS, which contains memory mappings specific to Linux
(it contains the contents of /proc/self/maps). This CL allows the minidump
to gather information from the memory mappings for Linux minidumps.
In addition, exploitability rating for Linux dumps now use memory mappings
instead of checking the ELF headers of binaries. The basis for the change
is that checking the ELF headers requires the minidumps to store the memory
from the ELF headers, while the memory mapping data is already present,
meaning the size of a minidump will be unchanged.
As a result, of removing ELF header analysis, two unit tests have been removed.
Arguably, the cases that those unit tests check do not merit a high
exploitability rating and do not warrant a solid conclusion that was given
earlier.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1251593007
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1476 4c0a9323-5329-0410-9bdc-e9ce6186880e
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If the minidump module containing the instruction pointer has memory
containing the ELF header and program header table, when checking the
exploitability rating, the processor will use the ELF header data to determine
if the instruction pointer lies in an executable region of the module, rather
than just checking if it lies in a module.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1233973002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1472 4c0a9323-5329-0410-9bdc-e9ce6186880e
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When I first added the exception whitelist, I meant to put the check before
checking the location of the instruction pointer. (I didn't notice that it
was after the other check until now.) The whitelist check is to quickly rule
out minidumps, and if checking the instruction pointer provided any useful
information, it would be pretty indicative that the exception causing the
dump is interesting.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1211253009
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1469 4c0a9323-5329-0410-9bdc-e9ce6186880e
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finding the instruction/stack pointer for exploitability rating.
There was already a method that found the instruction pointer, so the files
for exploitability ratings had repeated code. Also a method for finding the
stack pointer is implemented in this CL.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1210943005
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1468 4c0a9323-5329-0410-9bdc-e9ce6186880e
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If the exception reponsible for the crash is benign, such as a floating point
exception, we can rule out the possibility that the code is exploitable. This
CL checks for such exceptions and marks the dump as not exploitable if such an
exception is found.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1212383004
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1467 4c0a9323-5329-0410-9bdc-e9ce6186880e
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exploitability ratings.
The stackwalker will now grab the instruction pointers for ARM and ARM64
architectures, so checking exploitability on ARM and ARM64 will no longer
return EXPLOITABILITY_ERR_PROCESSING.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1216063004
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1466 4c0a9323-5329-0410-9bdc-e9ce6186880e
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in valid code for Linux exploitability rating.
This CL adds to the Linux exploitability checker by verifying that the
instruction pointer is in valid code. Verification is done by obtaining a
memory mapping of the crash and checking if the instruction pointer lies in
an executable region. If there is no memory mapping, the instruction pointer
is checked to determine if it lies within a known module.
R=ivanpe@chromium.org
Review URL: https://codereview.chromium.org/1210493003
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1464 4c0a9323-5329-0410-9bdc-e9ce6186880e
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The current code is relying on info->si_pid to figure out whether
the exception handler was triggered by a signal coming from the kernel
(that will re-trigger until the cause that triggered the signal has
been cleared) or from user-space e.g., kill -SIGNAL pid, which will NOT
automatically re-trigger in the next signal handler in the chain.
While the intentions are good (manually re-triggering user-space
signals), the current implementation mistakenly looks at the si_pid
field in siginfo_t, assuming that it is coming from the kernel if
si_pid == 0.
This is wrong. siginfo_t, in fact, is a union and si_pid is meaningful
only for userspace signals. For signals originated by the kernel,
instead, si_pid overlaps with si_addr (the faulting address).
As a matter of facts, the current implementation is mistakenly
re-triggering the signal using tgkill for most of the kernel-space
signals (unless the fault address is exactly 0x0).
This is not completelly correct for the case of SIGSEGV/SIGBUS. The
next handler in the chain will stil see the signal, but the |siginfo|
and the |context| arguments of the handler will be meaningless
(retriggering a signal with tgkill doesn't preserve them).
Therefore, if the next handler in the chain expects those arguments
to be set, it will fail.
Concretelly, this is causing problems to WebView. In some rare
circumstances, the next handler in the chain is a user-space runtime
which does SIGSEGV handling to implement speculative null pointer
managed exceptions (see as an example
http://www.mono-project.com/docs/advanced/runtime/docs/exception-handling/)
The fix herein proposed consists in using the si_code (see SI_FROMUSER
macros) to determine whether a signal is coming form the kernel
(and therefore just re-establish the next signal handler) or from
userspace (and use the tgkill logic).
Repro case:
This issue is visible in Chrome for Android with this simple repro case:
- Add a non-null pointer dereference in the codebase:
*((volatile int*)0xbeef) = 42
Without this change: the next handler (the libc trap) prints:
F/libc ( 595): Fatal signal 11 (SIGSEGV), code 1, fault addr 0x487
where 0x487 is actually the PID of the process (which is wrong).
With this change: the next handler prints:
F/libc ( 595): Fatal signal 11 (SIGSEGV), code 1, fault addr 0xbeef
which is the correct answer.
BUG=chromium:481937
R=mark@chromium.org
Review URL: https://breakpad.appspot.com/6844002.
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1461 4c0a9323-5329-0410-9bdc-e9ce6186880e
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