Mark a CIE with a S in its augmentation string as signal frame.
This allows the code to properly handle signal frame data if none
of the signal frame pattern matchers work.
For a signal frame, DwarfSectionImpl<AddressType>::Eval needs to
continue the unwinding even if PC is zero. A zero PC means that the
program has crashed, and we should try to recover the real PC using the
return address on the stack or LR. This behavior is tested by
UnwindOffline.signal_{x86,x86_64}, which modify the libc.so files
so that the signal frame pattern matcher fails and the CIE/FDE
data is used instead.
Test: libunwindstack_test
Change-Id: I4655b070028fd984345311a5e743796f8c30ed36
We're now using it in contexts that don't have all of the registers available,
such as GWP-ASan and soon MTE, so it doesn't make sense to have it be a
member function of Regs.
Bug: 135772972
Change-Id: I18b104ea0adb78588d7e475d0624cefc701ba52c
This refactors the step function slightly to split it up into
distinct pieces since the code needs to handle a signal handler
versus normal step slightly differently.
Add a new error for an invalid elf.
Modify libbacktrace code to handle new error code.
Bug: 130302288
Test: libbacktrace/libunwindstack unit tests.
Change-Id: I3fb9b00c02d2cf2cc5911541bba0346c6f39b8e6
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
This object is for doing many local unwinds across different threads
at any point during a program's execution.
Also add LocalUpdatableMaps that will re-read the maps data under certain
circumstances.
This first version does not support jit or dex pc data.
Bug: 74361929
Test: Ran unit tests.
Change-Id: I790662366d3fed677f31b3288182950c494de9ad
