Various ASan interceptors may corrupt memory if passed a
pointer to freed memory (https://github.com/google/sanitizers/issues/321).
This patch fixes the issue for the backtrace interceptor,
by calling REAL(backtrace) with a known-good scratch buffer,
and performing an addressability check on the user-provided
buffer prior to writing to it.
Differential Revision: https://reviews.llvm.org/D150496
My newly added backtrace test (https://reviews.llvm.org/D150491)
broke the Windows buildbot (https://lab.llvm.org/buildbot/#/builders/127/builds/48103)
because they do not have execinfo.h.
I expect the same will happen with the backtrace_symbols test (https://reviews.llvm.org/D150498) as well.
This patch does a quick fix by restricting the test scope to glibc-2.27.
(A tricker fix would take into account SANITIZER_INTERCEPT_BACKTRACE,
which is defined as (SI_FREEBSD || SI_NETBSD || SI_GLIBC || SI_SOLARIS))
It is a known, longstanding issue that some ASan interceptors
may write to freed memory, causing corruption
(https://github.com/google/sanitizers/issues/321). This patch
adds a testcase for the backtrace interceptor (one of the
known cases).
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D150491
