MaybeReexec() does now a tricky job to manage DYLD_INSERT_LIBRARIES in a safe way.
Because we're using library interposition, it's critical for an instrumented app
to be executed with the runtime library present in DYLD_INSERT_LIBRARIES list.
Therefore if it's initially missing in that list, we append the runtime library name
to the value of DYLD_INSERT_LIBRARIES and then exec() ourselves.
On the other hand, some of the apps exec()ed by our program may not want to have
ASan runtime library preloaded, so we remove the runtime library from the
DYLD_INSERT_LIBRARIES if it's already there.
Users may want to preload other libraries using DYLD_INSERT_LIBRARIES, so we preserve those.
llvm-svn: 175276
When prelink is installed in the system, prelink-ed
libraries map between 0x003000000000 and 0x004000000000 thus occupying the shadow Gap,
so we need so split the address space even further, like this:
|| [0x10007fff8000, 0x7fffffffffff] || HighMem ||
|| [0x02008fff7000, 0x10007fff7fff] || HighShadow ||
|| [0x004000000000, 0x02008fff6fff] || ShadowGap3 ||
|| [0x003000000000, 0x003fffffffff] || MidMem ||
|| [0x00087fff8000, 0x002fffffffff] || ShadowGap2 ||
|| [0x00067fff8000, 0x00087fff7fff] || MidShadow ||
|| [0x00008fff7000, 0x00067fff7fff] || ShadowGap ||
|| [0x00007fff8000, 0x00008fff6fff] || LowShadow ||
|| [0x000000000000, 0x00007fff7fff] || LowMem ||
Do it only if necessary.
Also added a bit of profiling code to make sure that the
mapping code is efficient.
Added a lit test to simulate prelink-ed libraries.
Unfortunately, this test does not work with binutils-gold linker.
If gold is the default linker the test silently passes.
Also replaced
__has_feature(address_sanitizer)
with
__has_feature(address_sanitizer) || defined(__SANITIZE_ADDRESS__)
in two places.
Patch partially by Jakub Jelinek.
llvm-svn: 175263
Build system setup for MSan lit tests (build with freshly-built clang, run,
check output) - a nearly exact copy from ASan.
First 2 lit tests for MSan.
llvm-svn: 174876
This a rewrite of the scanf parser. The new implementation is pretty close to
the spec, with a few shortcuts taken here and there. It is conservative, i.e.
it gives up parsing if it does not understand some part of the format string,
or runs into an ambiguous % spec. It does not handle some rarely used parts of
the spec, like %n$ - for now.
I'm also moving parser call to after the original *scanf function completes,
so that we can find out the store size of %s directive by the use of strlen()
on the target buffer.
llvm-svn: 174704
Also fix large_func_test.cc, which got broken when we switched to allocator2: the OOB access was too far from the original allocation, so ASan decided to describe the next one.
llvm-svn: 174626