Hi,
This series adds minimalistic support for Memory Sanitizer (MSan) [1].
MSan is compiler instrumentation for detecting accesses to
uninitialized memory.
The motivation behind this is to be able to link elfutils into projects
instrumented with MSan, since it essentially requires all the code
running in a process to be instrumented.
The goal is to provide a setup where elfutils is linked only with zlib
and most tests pass. Here is the description of the setup that I'm
using:
- LLVM with argp_parse() instrumentation [2].
- zlib-ng instrumented with MSan:
git clone g...@github.com:zlib-ng/zlib-ng.git
cmake -DWITH_SANITIZER=Memory -DZLIB_COMPAT=ON -DWITH_GTEST=OFF \
-DCMAKE_C_COMPILER=clang -DCMAKE_INSTALL_PREFIX=/tmp/zlib-ng
make install
export CPATH=/tmp/zlib-ng/include
export LIBRARY_PATH=/tmp/zlib-ng/lib
- Hack: zlib is used by a lot of system utilities, so adding
MSan-instrumented zlib to LD_LIBRARY_PATH causes a lot of grief.
Let elfutils test infrastructure add it there only for running
tests:
ln -s /tmp/zlib-ng/lib/libz.so.1 libelf/
- elfutils uses printf("%n"), so tweak MSan to unpoison the respective
arguments. Also disable fast unwinding to get better backtraces:
export MSAN_OPTIONS=check_printf=1,fast_unwind_on_malloc=0
- Minimal configuration of elfutils instrumented with MSan:
autoreconf -i
CC=clang ./configure --enable-maintainer-mode \
--enable-sanitize-memory --without-bzlib \
--without-lzma --without-zstd \
--disable-debuginfod --disable-libdebuginfod \
--disable-demangler
Results:
============================================================================
Testsuite summary for elfutils 0.188
============================================================================
# TOTAL: 235
# PASS: 221
# SKIP: 14
# XFAIL: 0
# FAIL: 0
# XPASS: 0
# ERROR: 0
============================================================================
The patches take care of the following:
- Fixing clang build.
- Adding small tweaks to get rid of false positives (no real issues
were found, most likely because elfutils is already tested with
valgrind).
- Dealing with "-self" tests, which now see MSan runtime compiled
into elfutils binaries.
- MSan enablement itself.
[1] https://clang.llvm.org/docs/MemorySanitizer.html
[2] https://reviews.llvm.org/D143330
Best regards,
Ilya
Ilya Leoshkevich (11):
libdwfl: Fix debuginfod_client redefinition
libasm: Fix xdefault_pattern initialization
printversion: Fix unused variable
readelf: Fix set but not used parameter
readelf: Fix set but not used variable
Initialize reglocs for VMCOREINFO
addr2line: Do not test demangling in run-addr2line-i-test.sh
x86_64_return_value_location: Support lvalue and rvalue references
configure: Use -fno-addrsig if possible
configure: Add --disable-demangle
configure: Add --enable-sanitize-memory
backends/linux-core-note.c | 1 +
backends/x86_64_retval.c | 2 ++
configure.ac | 40 ++++++++++++++++++++++++++++++++++-
debuginfod/Makefile.am | 3 ++-
lib/printversion.h | 3 ++-
libasm/Makefile.am | 3 ++-
libasm/asm_newscn.c | 5 ++---
libdw/Makefile.am | 3 ++-
libdwfl/debuginfod-client.c | 2 +-
libdwfl/libdwfl.h | 5 +----
libdwfl/libdwflP.h | 4 ++--
libelf/Makefile.am | 3 ++-
src/readelf.c | 3 +--
tests/Makefile.am | 10 ++++++++-
tests/run-addr2line-i-test.sh | 14 ++++++------
tests/run-readelf-self.sh | 5 +++++
tests/run-strip-reloc.sh | 5 +++++
tests/run-varlocs-self.sh | 5 +++++
18 files changed, 90 insertions(+), 26 deletions(-)
--
2.39.1
