Commit graph

14 commits

Author SHA1 Message Date
Christopher Ferris
4ae266ccbd Add indicator that an elf is memory backed.
Modify the unwinder library to indicate that at least one of the stack
frames contains an elf file that is unreadable.

Modify debuggerd to display a note about the unreadable frame and a possible
way to fix it.

Bug: 129769339

Test: New unit tests pass.
Test: Ran an app that crashes and has an unreadable file and verified the
Test: message is displayed. Then setenforce 0 and verify the message is
Test: not displayed.
Change-Id: Ibc4fe1d117e9b5840290454e90914ddc698d3cc2
2019-04-18 15:37:52 -07:00
Christopher Ferris
86f2d9d943 Fix missing offset for apk.
The elf_start_offset field in a map_info was not set in one path.

Added new offline test for this, and update a few unit tests.

Bug: 128442792

Test: New unit tests pass.
Change-Id: I2c6ac1b5271a99aa0e8c4b6342a5970199185112
2019-03-12 16:00:55 -07:00
Christopher Ferris
a09c4a6ff2 Fix offsets when shared lib split across maps.
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
2018-12-18 11:22:14 -08:00
Christopher Ferris
01040b10b2 Fix handling of ro segments for embedded libs.
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
2018-12-11 19:16:29 -08:00
Mark Salyzyn
9f1cf25332 switch to using android-base/file.h instead of android-base/test_utils.h
Test: compile
Bug: 119313545
Change-Id: I4f7ad84743e974b4b4d1d7256088f6c8b749a237
2018-11-14 09:35:34 -08:00
Christopher Ferris
9d5712c123 Implement support for linker rosegment option.
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
2018-10-03 20:48:45 -07:00
Treehugger Robot
b4fda18d83 Merge changes I53c2c560,I7d845ac5,I8b11d923
* changes:
  unwindstack: rename Memory::ReadPartially to Read.
  unwindstack: rename Memory::Read to ReadFully.
  unwindstack: add Memory::ReadPartially.
2017-12-02 00:12:21 +00:00
Christopher Ferris
be788d891d Allow multiple threads sharing a map to unwind.
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
2017-11-28 15:20:38 -08:00
Josh Gao
ef35aa5d40 unwindstack: rename Memory::Read to ReadFully.
Rename Memory::Read to ReadFully to match its semantics with that of
android::base. ReadPartially will be renamed to Read in a follow up
commit, kept intentionally separate so that there aren't any callers
accidentally switched from ReadFully to Read.

Test: treehugger
Change-Id: I7d845ac5244c3025d92c8512e960e5d0d1da05af
2017-11-15 15:38:13 -08:00
Christopher Ferris
5f118519fd Add a method to share the process memory object.
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
2017-09-05 14:30:22 -07:00
Christopher Ferris
3f805ac3f8 Add proper support for embedded elf files.
- 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
2017-08-30 15:50:11 -07:00
Christopher Ferris
d226a51409 Make the library usable as a library.
- 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
2017-07-14 12:20:23 -07:00
Christopher Ferris
2a25c4aab5 Add full support for initing registers.
- Fixes a few bugs in untested functionality.
- Add tests for the way the register handling code is used.
- Fix a few tests that were not reaping child processes.

Bug: 23762183

Test: Ran unit tests on host (32 bit and 64 bit).
Test: Ran unit tests on angler (32 bit and 64 bit).
Change-Id: I573d6617b4f1561f6e8494d7213c52086d112d97
2017-07-11 12:15:54 -07:00
Christopher Ferris
570b76f04f Init .gnu_debugdata in GetElf().
- 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
2017-06-30 17:24:58 -07:00
Renamed from libunwindstack/tests/MapInfoTest.cpp (Browse further)