This is done by creating a named shared memory region, unlinking it
and setting up a private (i.e. copy-on-write) mapping of that instead
of a regular anonymous mapping. I've experimented with regular
(sparse) files, but they can not be scaled to the size of MSan shadow
mapping, at least on Linux/X86_64 and ext3 fs.
Controlled by a common flag, decorate_proc_maps, disabled by default.
This patch has a few shortcomings:
* not all mappings are annotated, especially in TSan.
* our handling of memset() of shadow via mmap() puts small anonymous
mappings inside larger named mappings, which looks ugly and can, in
theory, hit the mapping number limit.
llvm-svn: 238621
dl_iterate_phdr is somewhat broken in L (see the code for details).
We add runtime OS version detection and fallback to /proc/maps on L or earlier.
This fixes a number of ASan tests on L.
llvm-svn: 236628
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
It was happening when we looked up a PC for a module that was dlopen'ed/dlclose'd
after the last time we fetched the list of modules
Reviewed at http://reviews.llvm.org/D8618
llvm-svn: 233257
The problem is that without SA_RESTORER flag, kernel ignores the handler. So tracer actually did not setup any handler.
Add SA_RESTORER flag when setting up handlers.
Add a test that causes SIGSEGV in stoptheworld callback.
Move SignalContext from asan to sanitizer_common to print better diagnostics about signal in the tracer thread.
http://reviews.llvm.org/D8005
llvm-svn: 230978
The ASanified executable could be launched from different locations. When we
cannot find the suppression file relative to the current directory, try to
see if the specified path is relative to the location of the executable.
llvm-svn: 230723
This is a re-commit of r224838 + r224839, previously reverted in r224850.
Test failures were likely (still can not reproduce) caused by two lit tests
using the same name for an intermediate build target.
llvm-svn: 224853
Summary:
- Make sure mmap() is never called inside RawWrite function.
- Wrap a bunch of standalone globals in a ReportFile object.
- Make sure accesses to these globals are thread-safe.
- Fix report_path functionality on Windows, where
__sanitizer_set_report_path() would break program.
I've started this yak shaving in order to make
"CommonFlags::mmap_limit_mb" immutable. Currently we drop this flag
to zero before printing an error message.
Test Plan: regression test suite
Reviewers: kcc, glider
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6595
llvm-svn: 224031
Summary:
TestCases/Linux/heavy_uar_test.cc was failing on my
PowerPC64 box with GCC 4.8.2, because the compiler recognised
a memset-like loop and turned it into a call to memset, which
got intercepted by __asan_memset, which got upset because it was
being called on an address in high shadow memory.
Use break_optimization to stop the compiler from doing this.
Reviewers: kcc, samsonov
Reviewed By: kcc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6266
llvm-svn: 222572
MSanDR is a dynamic instrumentation tool that can instrument the code
(prebuilt libraries and such) that could not be instrumented at compile time.
This code is unused (to the best of our knowledge) and unmaintained, and
starting to bit-rot.
llvm-svn: 222232
Summary:
This commit introduces function __sanitizer::RenderFrame()
that allows to render the contents of AddressInfo (essentially, symbolized stack frame)
using the custom format string. This function can be used to
implement stack frame formatting for both ThreadSanitizer and
generic StackTrace::Print(), used in another places. This paves the
way towards allowing user to control the format of stack frames,
obtaining them in any format he desires, and/or enforcing the consistent
output from all sanitizers.
Test Plan: compiler-rt test suite
Reviewers: kcc
Reviewed By: kcc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6140
llvm-svn: 221409
By default summary is not printed if UBSan is run in a standalone mode,
but is printed if it's combined with another sanitizer (like ASan).
llvm-svn: 218135
Summary:
UBSan needs to check if memory snippet it's going to print resides
in addressable memory. Similar check might be helpful in ASan with
dump_instruction_bytes option (see http://reviews.llvm.org/D5167).
Instead of scanning /proc/self/maps manually, delegate this check to
the OS kernel: try to write this memory in a syscall and assume that
memory is inaccessible if the syscall failed (e.g. with EFAULT).
Fixes PR20721.
Test Plan: compiler-rt test suite
Reviewers: eugenis, glider
Reviewed By: glider
Subscribers: emaste, ygribov, llvm-commits, glider, rsmith
Differential Revision: http://reviews.llvm.org/D5253
llvm-svn: 217971