When LinuxCoreDumper fails to copy process data from a core file, it
fills the return buffer with a repeated sequence of a special marker.
However, MinidumpWriter doesn't know about that and may incorrectly
interpret the data. In many cases, MinidumpWriter simply copies the
gibberish data to the minidump, which isn't too bad. However, the
gibberish data may cause MinidumpWriter to behave badly in some other
cases. For example, when MinidumpWriter tries to iterate through the
linked list of all loaded DSOs via the r_map field of a r_debug struct,
if the linked list is filed with the special marker, the code keeps
iterating through the same address.
This CL addresses the issue by having LinuxCoreDumper::CopyFromProcess()
returns a Boolean value to indicate if the expected data is found from
the core file. MinidumpWriter can then decide how to handle that.
BUG=chromium:453484
TEST=Run core2md with the test data attached to chromium:453484.
R=mark@chromium.org
Review URL: https://breakpad.appspot.com/4724002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1420 4c0a9323-5329-0410-9bdc-e9ce6186880e
Microdumps are a very lightweight variant of minidumps. They are meant
to dump a minimal crash report on the system log (logcat on Android),
containing only the state of the crashing thread.
This is to deal with cases where the user has opted out from crash
uploading but we still want to generate meaningful information on the
device to pull a stacktrace for development purposes.
Conversely to conventional stack traces (e.g. the one generated by
Android's debuggerd or Chromium's base::stacktrace) microdumps do NOT
require unwind tables to be present in the target binary. This allows
to save precious binary size (~1.5 MB for Chrome on Arm, ~10 MB on
arm64).
More information and design doc on crbug.com/410294
BUG=chromium:410294
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1398 4c0a9323-5329-0410-9bdc-e9ce6186880e
This is a refactoring of the logic which determines the
module name and path for a given MappingInfo in minidump_writer.cc.
Such logic, which will be soon shared also with the upcoming
microdump_writer.cc, is simply being moved to linux_dumper.cc,
extracting a GetMappingEffectiveNameAndPath method.
No behavioral change is intended.
BUG=chromium:410294
R=thestig@chromium.org
Review URL: https://breakpad.appspot.com/7734002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1392 4c0a9323-5329-0410-9bdc-e9ce6186880e
This change is a pure refactoring of the common bits of minidump_writer.cc
that will be shared soon with the upcoming microdump_writer.cc.
In particular, this CL is extracting the following classes:
- ThreadInfo: handles the state of the threads in the crashing process.
- RawContextCPU: typedef for arch-specific CPU context structure.
- UContextReader: Fills out a dump RawContextCPU structure from the
ucontext struct provided by the kernel (arch-dependent).
- SeccompUnwinder: cleans out the stack frames of the Seccomp sandbox
on the supported architectures.
- MappingInfo: handles information about mappings
BUG=chromium:410294
R=mmandlis@chromium.org
Review URL: https://breakpad.appspot.com/4684002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1388 4c0a9323-5329-0410-9bdc-e9ce6186880e
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
R=rmcilroy@chromium.org, thestig@chromium.org
Review URL: https://breakpad.appspot.com/7714003
Patch from Simon Baldwin <simonb@chromium.org>.
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1380 4c0a9323-5329-0410-9bdc-e9ce6186880e
This patch makes two changes to breakpad to enable crash reporting to work correctly when the library is inside another file (an archive):
- Do not filter mappings which map an executable at a non-zero offset.
- If such an executable is mapped look in the ELF information for the
shared object name and use that name in the minidump.
Note this change doesn't care about the archive format and isn't Android
specific (though loading the shared library this way is currently only done on Android).
BUG=390618
R=thestig@chromium.org
Review URL: https://breakpad.appspot.com/7684002
Patch from Anton Carver <anton@chromium.org>.
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1355 4c0a9323-5329-0410-9bdc-e9ce6186880e
__system_property_get has been removed from the Android NDK for 'L' so Breakpad
no longer links. This CL just removes the call in WriteOSInformation because
Chrome already passes the build fingerprint as a crash key called "android_build_fp" in the crash report HTTP POST message.
BUG=394841,393903
R=mark@chromium.org
Review URL: https://breakpad.appspot.com/1694002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1351 4c0a9323-5329-0410-9bdc-e9ce6186880e
This is an initial attempt to add Arm64 (aarch64) support to Breakpad for
Linux / Android platforms. This CL adds the Arm64 data structures, but does
not yet implement the Android getcontext support or CPUFillFromThreadInfo /
CPUFillFromUContext.
BUG=354405,335641
R=mark@chromium.org
Review URL: https://breakpad.appspot.com/1354002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1301 4c0a9323-5329-0410-9bdc-e9ce6186880e
The current CreateChildCrash logic is racy when it comes to creating a
crash dump for two reasons:
The main thread that calls kill() on a different thread is guaranteed
the signal will be *queued* when it returns, but not *delivered*. If
the kernel doesn't automatically schedule the receiving thread, but
instead lets the main thread run to the exit() call, then the signal
never triggers a coredump and the whole process simply exits.
The main thread is using kill() to try to deliver a signal to a
specific thread, but that function is for sending signals to a
process. That means the kernel is free to deliver the signal to
any thread in the process and not just the one requested. This
manifests itself as the pr_pid in the coredump not being the one
expected. Instead, we must use tkill() with the tid (which we
already took care of gathering) to deliver to a specific thread.
These are a lot easier to see on a UMP system as contention is heavier.
BUG=chromium:207918
TEST=`dumper_unittest` still passes, and doesn't flake out in a UMP system
TEST=`linux_client_unittest` still passes
R=benchan@chromium.org
Review URL: https://breakpad.appspot.com/1304005
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1299 4c0a9323-5329-0410-9bdc-e9ce6186880e
For CPUs that don't support the MMX instruction set, such pre-Pentium III or industrial x86 embedded PCs, the minidump fails when it tries to retrieve MMX specific registers.
This patch adds MMX detection for that call.
Tested on Ubuntu 12.04 with i686, and on a custom Linux distro on a Vortex86DX microcontroller.
Original review: https://breakpad.appspot.com/455002/
A=aras.vaichas
BUG=495
Review URL: https://breakpad.appspot.com/864002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1248 4c0a9323-5329-0410-9bdc-e9ce6186880e
It is incorrect to wrap close in HANDLE_EINTR on Linux.
Unnecessary #includes of eintr_wrapper.h are also removed. The variable naming
within the macro is also updated per Chromium r178174.
einter_wrapper.h contains a non-mechanical change. Mechanical changes were
generated by running:
sed -E -i '' \
-e 's/((=|if|return|CHECK|EXPECT|ASSERT).*)HANDLE(_EINTR\(.*close)/\1IGNORE\3/' \
-e 's/(ignore_result|void ?)\(HANDLE_EINTR\((.*close\(.*)\)\)/\2/' \
-e 's/(\(void\) ?)?HANDLE_EINTR\((.*close\(.*)\)/\2/' \
$(grep -rl HANDLE_EINTR.*close . --exclude-dir=.svn)
sed -E -i '' -e '/#include.*eintr_wrapper\.h"/d' \
$(grep -EL '(HANDLE|IGNORE)_EINTR' \
$(grep -Elr '#include.*eintr_wrapper\.h"' . --exclude-dir=.svn))
BUG=chromium:269623
R=ted.mielczarek@gmail.com
Review URL: https://breakpad.appspot.com/784002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1239 4c0a9323-5329-0410-9bdc-e9ce6186880e
This patch improves several things for Linux/ARM:
- Better detection of the number of CPUs on the target
device. The content of /proc/cpuinfo only matches the
number of "online" CPUs, which varies over time with
recent Android devices.
- Reconstruct the CPUID and ELF hwcaps values from
/proc/cpuinfo, this is useful to better identify
target devices in minidumps.
- Make minidump_dump display the new information
in useful ways.
- Write a small helper class to parse /proc/cpuinfo
and also use it for x86/64.
- Write a small helper class to parse sysfds cpu lists.
- Add a my_memchr() implementation.
- Add unit tests.
Tested on a Nexus S (1 CPU), Galaxy Nexus (2 CPUs)
and a Nexus 4 (4 CPUs).
Review URL: https://breakpad.appspot.com/540003
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1160 4c0a9323-5329-0410-9bdc-e9ce6186880e
If the stack sizes for threads in the MinidumpSizeLimit test are too big,
then subtracting 64KB from the normal minidump file size is not enough to
trigger the size-limiting logic. Instead of basing the arbitrary limit off
of the normal file size, make it relative to the 8KB stack size the logic
assumes.
BUG=google-breakpad:510
TEST=Ran unittests
Review URL: https://breakpad.appspot.com/504002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1090 4c0a9323-5329-0410-9bdc-e9ce6186880e
When there are upwards of 200 threads in a crashing process, each having an
8KB stack, this can result in a huge, 1.8MB minidump file. So I added a
parameter that, if set, can compel the minidump writer to dump less stack.
More specifically, if the writer expects to go over the limit (due to the
number of threads), then it will dump less of a thread's stack after the
first 20 threads.
There are two ways to specify the limit, depending on how you write minidumps:
1) If you call WriteMinidump() directly, there's now a version of the
function that takes the minidump size limit as an argument.
2) If you use the ExceptionHandler class, the MinidumpDescriptor object you
pass to it now has a set_size_limit() method you would call before
passing it to the constructor.
BUG=chromium-os:31447, chromium:154546
TEST=Wrote a size-limit unittest; Ran unittests
Review URL: https://breakpad.appspot.com/487002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1082 4c0a9323-5329-0410-9bdc-e9ce6186880e
- One of the unit test binaries refused to link due to
missing linker flags.
- The WriteDSODebug() function now works on Android, so
do not special-case it anymore.
- Ensure android/run-checks.sh will complain properly if
the client unit test suite fails on Android. It used to
consider that such failures were acceptable. Note that
it still considers failures when running the tools and
processor test suite on the device normal (fixing this
is a lot harder, and these parts of Breakpad typically
never run on a device, but on the host).
Review URL: https://breakpad.appspot.com/482002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1066 4c0a9323-5329-0410-9bdc-e9ce6186880e
Currently, if a thread's stack pointer is not within a valid memory page,
the minidump writing will fail with an error. This change allows an invalid
stack pointer by simply setting the memory size to zero in the minidump.
The processing code already checks for the size being zero, although it
currently just gives an error (see https://breakpad.appspot.com/413002/).
BUG=google-breakpad:499, chromium-os:34880
TEST=make check, manually ran minidump-2-core and core2md
Review URL: https://breakpad.appspot.com/478002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1065 4c0a9323-5329-0410-9bdc-e9ce6186880e
