On Windows, we have to know if a memory to be protected is mapped or not.
On POSIX, Mprotect was semantically different from mprotect most people know.
llvm-svn: 234602
A flexible way of describing MSan memory layout details on various
platforms. No significant functional changes, but the memory layout
description that you get at verbosity=1 looks slightly different.
This change includes stronger sanity checks than before.
The goal of this change is to allow more than 2 application memory
ranges for https://code.google.com/p/memory-sanitizer/issues/detail?id=76.
llvm-svn: 227192
pthread_getspecific is not async-signal-safe.
MsanThread pointer is now stored in a TLS variable, and the TSD slot
is used only for its destructor, and never from a signal handler.
This should fix intermittent CHECK failures in MsanTSDSet.
llvm-svn: 224423
Summary:
The loader does not call mmap() through the PLT because it has to
bootstrap the process before libc is present. Hooking dlopen() isn't
enough either because the loader runs module initializers before
returning, and they could run arbitrary msan instrumented code.
If msandr is present, then we can intercept the mmaps from dlopen at the
syscall layer and clear the shadow there. If msandr is missing, we
clear the shadow after dlopen() and hope any initializers are trivial.
Reviewers: eugenis
CC: kcc, llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D509
llvm-svn: 176818
Timur Iskhodzhanov