Summary:
Before unwinding the stack, `__asan_handle_no_return` is supposed to
unpoison the entire stack - that is, remove the entries in the shadow
memory corresponding to stack (e.g. redzone markers around variables).
This does not work correctly if `__asan_handle_no_return` is called from
the alternate stack used in signal handlers, because the stack top is
read from a cache, which yields the default stack top instead of the
signal alternate stack top.
It is also possible to jump between the default stack and the signal
alternate stack. Therefore, __asan_handle_no_return needs to unpoison
both.
Reviewers: vitalybuka, kubamracek, kcc, eugenis
Reviewed By: vitalybuka
Subscribers: phosek, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D76986
Summary: This adds a customization point to support unpoisoning of signal alternate stacks on POSIX.
Reviewers: vitalybuka
Reviewed By: vitalybuka
Subscribers: #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D81577
The fallback to the alternative implementation of TSD with TLS
is only needed for the static version of ASan for NetBSD.
The same code cannot be reused for the dynamic version of ASan as
TLS breaks and TSD code works.
llvm-svn: 368219
Vitaly Buka