The x86-64 frame pointer-based unwind method will accept values
that aren't valid for the frame pointer register and the return address.
This fixes it to reject non-8-byte-aligned frame pointers, as
well as non-canonical addresses for the return address it finds.
A colleague of mine asked me why Breakpad gave a bad stack
for a crash in our crash-stats system:
https://crash-stats.mozilla.com/report/index/a472c842-2c7b-4ca7-a267-478cf2160405
Digging in, it turns out that the function in frame 0 is a leaf function,
so MSVC doesn't generate an entry in the unwind table for it, so
dump_syms doesn't produce a STACK CFI entry for it in the symbol file.
The stackwalker tries frame pointer unwinding, and %rbp is set to a
value that sort-of works, so it produces a garbage frame 1 and then
is lost. Either of the two checks in this patch would have stopped
the stackwalker from using the frame pointer.
It's possible we could do something smarter on the dump_syms side,
like enumerating all functions and outputing some default STACK CFI rule
for those that don't have unwind info, but that wouldn't fix crashes
from existing builds without re-dumping symbols for them. In any event,
these checks should always pass for valid frame pointer-using functions.
R=mark@chromium.org
BUG=https://bugzilla.mozilla.org/show_bug.cgi?id=1263001
Review URL: https://codereview.chromium.org/1902783002 .
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 .
More specifically:
- Detect corrupt symbols during minidump processing and provide the list of modules with corrupt symbols in the ProcessState. This will allow listing the corrupt symbol files in the final crash report.
- Skip and recover from symbol data parse errors - don't give up until 100 parse errors are seen.
- In order to recover from '\0' (null terminator) in the middle of a symbol file, a couple of methods have to be updated to require both buffer pointer and length. Previously they required only a buffer pointer (char *) and the size of the buffer was evaluated using strlen which is not reliable when the data is corrupt. Most of the changes are due to these signature updates.
- Added and updated unittests.
Also, updated minidump_stackwalk to show a WARNING for corrupt symbols. Output looks like this:
...
Loaded modules:
0x000da000 - 0x000dafff Google Chrome Canary ??? (main)
0x000e0000 - 0x0417dfff Google Chrome Framework 0.1500.0.3 (WARNING: Corrupt symbols, Google Chrome Framework, 4682A6B4136436C4BFECEB62D498020E0)
0x044a8000 - 0x04571fff IOBluetooth 0.1.0.0
...
Review URL: https://breakpad.appspot.com/613002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1200 4c0a9323-5329-0410-9bdc-e9ce6186880e
The google_breakpad::TestAssembler classes are used in both the processor's
and the Linux dumper's test suites, and will soon be used in the Mac
dumper's tests as well. This patch moves their source files from
src/processor to src/common.
a=jimblandy, r=thestig
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@574 4c0a9323-5329-0410-9bdc-e9ce6186880e
This adds support for 'STACK CFI' records (DWARF CFI) to the AMD64
stack walker. This is necessary for the stack trace to include any
frames other than the youngest. Unit tests are included.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@554 4c0a9323-5329-0410-9bdc-e9ce6186880e
