This object is able to be easily used from other code and can be used
to replace the libbacktrace calls in other parts of the platform.
Also, demangle the function names when calling FormatFrame.
Bug: 120606663
Test: Unit tests pass, debuggerd using this code directly passes unit
Test: tests.
Change-Id: Ifd8cf9bdd89174c1736810711d20e9f37f29b1bf
The linker was modified so that a shared library has a read-only
map, then a read-execute map to represent the whole shared library.
When backtraces are created, then the offsets are set incorrectly
for backtraces. For example, all backtraces wind up with an offset now,
and a shared library loaded out of an apk shows the wrong offset.
Changes:
- Fix the FormatFrame function which was putting the offset before the
map name.
- Refactor the Maps and MapInfo classes to keep track of the previous map
instead of all maps. This was the only map that was ever needed.
- Modify the unwind_for_offline tool to capture both the read-only and
read-execute map when using the read-only segment option.
Bug: 120981155
Test: Updated unit tests pass.
Test: Unwinds on device don't show the offsets everywhere any more.
Change-Id: I75b3727221be9c20316dfdcd7a1c6d242d7ce948
When a shared library is loaded directly from an apk, the new way the
linker splits a shared library into a read-only and execute segment
broke unwinding. Modify the code to handle this case.
Other changes:
- Modify the algorithm for finding read-only map entries. Before, the code
would search the entire map for the closest offset. Now it simply looks
at the previous map. I did this because the old code was too lenient and
might still work even if the linker changes. I want this to break if the
linker behavior changes so that I can analyze the change.
- Update the tools to use PTRACE_SEIZE instead of PTRACE_ATTACH since
PTRACE_ATTACH doesn't work in all cases.
- Small refactor of the GetFileMemory function.
- Add new unit test cases and new offline unwind test cases.
Bug: 120618231
Test: Ran new unit tests, ran original failing test.
Change-Id: I4bade55cf33220d52f1d5e9b0cbbbcc8419669d4
Remove unit test that is not needed any more.
Slightly reorganize the code around the changed check.
Bug: 77958880
Test: Ran backtrace tests with new linker options.
Test: Ran libunwindstack unit tests.
Change-Id: Ie95707323fb51616a093cafb83e0343fa24e7e61
To avoid a case where a malicious app might try and trick the system to
create an elf and register object that mismatches, always verify that they
are the same arch.
Test: Ran unit tests.
Change-Id: I66978e9e02f8e4f396856912e7019528ead4838e
Every real call always sets the value to true to init the gnu_debugdata
interface, so remove this parameter.
Test: Builds, unit tests pass.
Change-Id: I07fb3adbbd5b65b51c0dc7608561e820a5095051
The function should have returned a bool, so now it does.
Also use a different lighter weight function for validating the elf
in one place that didn't need to keep the max size value.
Test: Unit tests pass.
Change-Id: Ibde674e608091ba04abf22fad2fdc4dbdb2c6e73
The rosegment linker option results in two maps containing the elf data
existing. One is an execute map where the code lives, and the other is the
read-only segment which contains the elf header information. If the file
backing a shared library in memory is not readable, then the new code
will attempt to find the read-only map that has the same name as the
current execute segment, and that is at offest zero in the file.
Add new unit tests for this functionality.
Add the missing MapInfoCreateMemoryTest.cpp to the list of tests.
Bug: 109657296
Test: Pass new unit tests.
Test: All unit libbacktrace/libunwindstack tests pass with rosegment enabled.
Change-Id: If8f69e4a067d77b3f2a7c31e2e5cd989a0702a8c
- Add a load_bias field in MapInfo so that it can be loaded offline,
and also so it can be cached.
- Add an Add function to the Maps class so that it's possible to manually
create a map.
- Remove the OfflineMaps class since I haven't found a reason for this to
exist.
- Add a pointer to the gnu debugdata compressed section in the interface
itself and modify the step path to try eh_frame, then debug_frame, then
gnu_debugdata. This way arm can add exidx as the last step behind
gnu_debugdata. Add an offline test to verify the order of unwind.
- Fix x86_64_ucontext_t since it was a different size on 32 bit and 64 bit
systems.
Test: Pass new unit tests.
Change-Id: I978b70d6c244bd307c62a29886d24c1a8cb2af23
Add a static GetLoadBias method to the Elf object that only reads just
enough to get the load bias.
Add a method to MapInfo that gets the load bias. First attempt to get
it if the elf object already exists. If no elf object was created, use
the new static method to get the load bias.
In BacktraceMap, add a custom iterator so that when code dereferences
a map element, that's when the load bias will be retrieved if it hasn't
already been set.
Bug: 69871050
Test: New unit tests, verify tombstones have non-zero load bias values for
Test: libraries with a non-zero load bias.
Change-Id: I125f4abc827589957fce2f0df24b0f25d037d732
Add a mutex in MapInfo, and a mutex in Elf. Lock the creation of an Elf
file using the MapInfo mutex, and lock when calling Step, GetFunctionName,
or GetSoname since they can modify information in the object. It might
be beneficial to use a fine grained lock in the future.
Change the Maps object to contain a vector of MapInfo pointers rather
than the total objects. This avoids copying this data around.
Add a test to libbacktrace to verify that sharing a map while doing
unwinds in different threads works.
Add concurrency tests in libunwindstack to verify the locking works.
Add always inline to the RegsGetLocal arm and aarch64 functions. I had
a case where clang did not inline the code, so make sure this is specified.
Bug: 68813077
Test: New unit tests to cover the case. Passes all unit tests.
Test: Ran a monkey test while dumping bugreports and verified that
Test: no crashes in libunwind.
Test: Remove the locking and verified that all of the concurrenty tests fail.
Change-Id: I769e728c676f6bdae9e64ce4cdc03b6749beae03
Add a way to read while allowing for partial reads.
Test: new tests added to libunwindstack_test, ran 32/64 on hikey960, sailfish
Test: ran unwind on hikey960/sailfish
Change-Id: I8b11d9230fcd3122148ef3f980863ac1404ad70a
- Move the load bias stored out of ElfInterface into Elf. For the compressed
sections, the load bias was not the same as the data from the uncompressed
section.
- Move the initialization of the compressed section into Init. It was too easy
to forget to call the init of the compressed section.
- Do not automatically add in load bias to the pc before calling ElfInterface
code. Do all of the pc manipulations in the Elf object.
- Change the interface GetFunctionName code to pass in the load_bias instead
of modifying the pc inside the code.
- Modify the Step function to pass in the elf offset, not add it to the pc.
It is necessary to have two different relative values when executing the
Step: a pc that is relative to the beginning of the elf for the reading data
the actual instructions when trying to determine if this is in a signal
frame, and a pc that is relative to the map for finding the appropriate
unwind information.
- Add a feature to Unwinder so that an unwind can be stopped if it ends up
in map that has a specified suffix. This is so that the ART unwinding
code doesn't require skipping the compressed section. Instead, stop at
if trying to unwind through a known suffix code that means the code is
in java code. This is important because the compressed section data is
not only used by the jave compiled code, so that will continue to work.
- Fix tests for restructuring, add new tests for new functionality.
Test: Ran art test 137-cfi using new unwinder as default.
Test: Ran new unit tests.
Change-Id: I42e658c64c5e14f698ba34944a3043afac967884
New function to create the process memory object. This allows for
a future where different remote process memory objects could be created
depending on the way remote memory can be created. Even different local
memory objects that access memory without doing any checks.
It also allows MemoryRange objects to share one single process memory object
and could help if the process memory object caches data.
Small changes to MapInfo::CreateMemory to when some errors are detected.
- Always check if the map is a device map, instead of only if the name
is not empty.
- Check if a memory map is readable before creating the memory from process
memory.
Bug: 23762183
Test: Ran unit tests, unwound on device using the new code.
Change-Id: I12a93c2dc19639689a528ec41c67bfac74d431b3
- Add a method to get the max size of an elf file by reading the
section header offset + size. This will properly map an elf
file embedded into an apk, instead of just mapping in what is done
by the dynamic linker. It does assume that the section headers are
at the end of the elf file.
- Add new tests for the above functionality.
- Update the unwind_symbols tool to take an address for finding a
function instead of dumping the entire symbol table.
Bug: 23762183
Test: Unit tests pass, unwind through the camera process and verify
Test: the GoogleCamera.apk shows some function names.
Change-Id: I00c021680fe1d43b60d652bf91bbf6667d9617be
- Add namespace unwindstack everywhere so that it's easier for other
code to use the library.
- Move some of the header files into include/unwindstack so that they
can be exposed.
- Modify the headers so that only a limited number need to be exposed.
- Update the tools to use the new headers.
- Add a GetLoadBias() call on the Elf object. This prevents the need
to get the interface object out of the Elf object.
- Move the GetRelPc() call out of the Reg class, to the Elf class. It's
not always the case that a Reg object will be around when you want to
get a relative pc. The tests for this moved to ElfTest.cpp.
Bug: 23762183
Test: Unit tests pass.
Change-Id: Iac609dac1dd90ed83d1a1e24ff2579c96c023bc3
- Modify the tests to share some code for the generation of the elf data.
- Move the gnu_debugdata files into a separate directory.
- Add tests for GetElf().
- Move the CreateMemory() tests and the GetElf() tests into separate files.
Bug: 23762183
Test: New unit tests pass.
Change-Id: Ie3380296bb49753c2ac8801cfa11f93d6ff7121d
