Handle ntdll only emitting PUBLIC at func entry

This handles a case encountered in ntdll.dll symbols for Windows 7,
where a PUBLIC would be emitted only for the entry point to the
function. The body of the function, however, is split in a PGO-ish
fashion to another remote location in the binary. Because of this, there
were large gaps in the RVA space that would be attributed to the "last"
function that happened to have an entry point before the gap. In
practice, something like this:

0x100 Func1
0x110 Func2
0x120 Func3
0x130 Func4
...
0x800 LaterFuncs

The bodies of Func1/2/3 tend to be implemented as a fast-path check,
followed by a jmp to somewhere in the range between 0x130 and 0x800.
Because no symbols are emitted for this range, everything is attributed
to Func4, causing crash misattribution.

In this CL, the change is: after emitting the entry point symbol, also
walk in the original OMAP entries through the untranslated binary, and
for each block until we resolve to a new symbol (via the same mechanism
as we found the entry point) emit another PUBLIC indicating that there's
another block that belongs to that symbol. This effectively breaks up
the "0x130 - 0x800" range above.

R=mark@chromium.org
BUG=chromium:678874

Change-Id: Ib3741abab2e7158c81e3e34bca4340ce4d3153a1
Reviewed-on: https://chromium-review.googlesource.com/446717
Reviewed-by: Mark Mentovai <mark@chromium.org>
3 files changed
tree: 23fedc3a7467afdec68e1b7c7678686f3a8dba97
  1. android/
  2. autotools/
  3. docs/
  4. m4/
  5. scripts/
  6. src/
  7. .gitignore
  8. .travis.yml
  9. aclocal.m4
  10. appveyor.yml
  11. AUTHORS
  12. breakpad-client.pc.in
  13. breakpad.pc.in
  14. ChangeLog
  15. codereview.settings
  16. configure
  17. configure.ac
  18. default.xml
  19. DEPS
  20. INSTALL
  21. LICENSE
  22. Makefile.am
  23. Makefile.in
  24. NEWS
  25. README.ANDROID
  26. README.md
README.md

Breakpad

Breakpad is a set of client and server components which implement a crash-reporting system.

Getting started (from master)

  1. First, download depot_tools and ensure that they’re in your PATH.

  2. Create a new directory for checking out the source code (it must be named breakpad).

    mkdir breakpad && cd breakpad
    
  3. Run the fetch tool from depot_tools to download all the source repos.

    fetch breakpad
    cd src
    
  4. Build the source.

    ./configure && make
    

    You can also cd to another directory and run configure from there to build outside the source tree.

    This will build the processor tools (src/processor/minidump_stackwalk, src/processor/minidump_dump, etc), and when building on Linux it will also build the client libraries and some tools (src/tools/linux/dump_syms/dump_syms, src/tools/linux/md2core/minidump-2-core, etc).

  5. Optionally, run tests.

    make check
    
  6. Optionally, install the built libraries

    make install
    

If you need to reconfigure your build be sure to run make distclean first.

To update an existing checkout to a newer revision, you can git pull as usual, but then you should run gclient sync to ensure that the dependent repos are up-to-date.

To request change review

  1. Follow the steps above to get the source and build it.

  2. Make changes. Build and test your changes. For core code like processor use methods above. For linux/mac/windows, there are test targets in each project file.

  3. Commit your changes to your local repo and upload them to the server. http://dev.chromium.org/developers/contributing-code e.g. git commit ... && git cl upload ... You will be prompted for credential and a description.

  4. At https://chromium-review.googlesource.com/ you'll find your issue listed; click on it, then “Add reviewer”, and enter in the code reviewer. Depending on your settings, you may not see an email, but the reviewer has been notified with google-breakpad-dev@googlegroups.com always CC’d.