This reverts commit 6911114d8c.
Broke the QEMU sanitizer bots due to a missing header dependency. This
actually needs to be fixed on the bot-side, but for now reverting this
patch until I can fix up the bot.
This patch moves -fsanitize=scudo to link the standalone scudo library,
rather than the original compiler-rt based library. This is one of the
major remaining roadblocks to deleting the compiler-rt based scudo,
which should not be used any more. The standalone Scudo is better in
pretty much every way and is much more suitable for production usage.
As well as patching the litmus tests for checking that the
scudo_standalone lib is linked instead of the scudo lib, this patch also
ports all the scudo lit tests to run under scudo standalone.
This patch also adds a feature to scudo standalone that was under test
in the original scudo - that arguments passed to an aligned operator new
were checked that the alignment was a power of two.
Some lit tests could not be migrated, due to the following issues:
1. Features that aren't supported in scudo standalone, like the rss
limit.
2. Different quarantine implementation where the test needs some more
thought.
3. Small bugs in scudo standalone that should probably be fixed, like
the Secondary allocator having a full page on the LHS of an allocation
that only contains the chunk header, so underflows by <= a page aren't
caught.
4. Slight differences in behaviour that's technically correct, like
'realloc(malloc(1), 0)' returns nullptr in standalone, but a real
pointer in old scudo.
5. Some tests that might be migratable, but not easily.
Tests that are obviously not applicable to scudo standalone (like
testing that no sanitizer symbols made it into the DSO) have been
deleted.
After this patch, the remaining work is:
1. Update the Scudo documentation. The flags have changed, etc.
2. Delete the old version of scudo.
3. Patch up the tests in lit-unmigrated, or fix Scudo standalone.
Reviewed By: cryptoad, vitalybuka
Differential Revision: https://reviews.llvm.org/D102543
Summary:
Original patch by Kuba Mracek
The %T lit expansion expands to a common directory shared between all
the tests in the same directory, which is unexpected and unintuitive,
and more importantly, it's been a source of subtle race conditions and
flaky tests. In https://reviews.llvm.org/D35396, it was agreed that it
would be best to simply ban %T and only keep %t, which is unique to each
test. When a test needs a temporary directory, it can just create one
using mkdir %t.
This patch removes %T in compiler-rt.
Differential Revision: https://reviews.llvm.org/D48618
llvm-svn: 336661
Summary:
Initially, Scudo had a monolithic design where both C and C++ functions were
living in the same library. This was not necessarily ideal, and with the work
on -fsanitize=scudo, it became more apparent that this needed to change.
We are splitting the new/delete interceptor in their own C++ library. This
allows more flexibility, notably with regard to std::bad_alloc when the work is
done. This also allows us to not link new & delete when using pure C.
Additionally, we add the UBSan runtimes with Scudo, in order to be able to have
a -fsanitize=scudo,undefined in Clang (see work in D39334).
The changes in this patch:
- split the cxx specific code in the scudo cmake file into a new library;
(remove the spurious foreach loop, that was not necessary)
- add the UBSan runtimes (both C and C++);
- change the test cmake file to allow for specific C & C++ tests;
- make C tests pure C, rename their extension accordingly.
Reviewers: alekseyshl
Reviewed By: alekseyshl
Subscribers: srhines, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D39461
llvm-svn: 317097
Summary:
The 64-bit primary has had random shuffling of chunks for a while, this
implements it for the 32-bit primary. Scudo is currently the only user of
`kRandomShuffleChunks`.
This change consists of a few modifications:
- move the random shuffling functions out of the 64-bit primary to
`sanitizer_common.h`. Alternatively I could move them to
`sanitizer_allocator.h` as they are only used in the allocator, I don't feel
strongly either way;
- small change in the 64-bit primary to make the `rand_state` initialization
`UNLIKELY`;
- addition of a `rand_state` in the 32-bit primary's `SizeClassInfo` and
shuffling of chunks when populating the free list.
- enabling the `random_shuffle.cpp` test on platforms using the 32-bit primary
for Scudo.
Some comments on why the shuffling is done that way. Initially I just
implemented a `Shuffle` function in the `TransferBatch` which was simpler but I
came to realize this wasn't good enough: for chunks of 10000 bytes for example,
with a `CompactSizeClassMap`, a batch holds only 1 chunk, meaning shuffling the
batch has no effect, while a region is usually 1MB, eg: 104 chunks of that size.
So I decided to "stage" the newly gathered chunks in a temporary array that
would be shuffled prior to placing the chunks in batches.
The result is looping twice through n_chunks even if shuffling is not enabled,
but I didn't notice any significant significant performance impact.
Reviewers: alekseyshl
Reviewed By: alekseyshl
Subscribers: srhines, llvm-commits, kubamracek
Differential Revision: https://reviews.llvm.org/D39244
llvm-svn: 316596
Summary:
Mark Android as supported in the cmake configuration for Scudo.
Scudo is not added yet in the Android build bots, but code builds and tests
pass locally. It is for a later CL. I also checked that Scudo builds as part
of the Android toolchain.
A few modifications had to be made:
- Android defaults to `abort_on_error=1`, which doesn't work well with the
current tests. So change the default way to pass `SCUDO_OPTIONS` to the tests
to account for this, setting it to 0 by default;
- Disable the `valloc.cpp` & `random_shuffle.cpp` tests on Android;
- There is a bit of gymnatic to be done with the `SCUDO_TEST_TARGET_ARCH`
string, due to android using the `-android` suffix, and `i686` instead of
`i386`;
- Android doesn't need `-lrt`.
Reviewers: alekseyshl, eugenis
Reviewed By: alekseyshl
Subscribers: srhines, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D37907
llvm-svn: 313538
Remove the explicit i686 target that is completely duplicate to
the i386 target, with the latter being used more commonly.
1. The runtime built for i686 will be identical to the one built for
i386.
2. Supporting both -i386 and -i686 suffixes causes unnecessary confusion
on the clang end which has to expect either of them.
3. The checks are based on wrong assumption that __i686__ is defined for
all newer x86 CPUs. In fact, it is only declared when -march=i686 is
explicitly used. It is not available when a more specific (or newer)
-march is used.
Curious enough, if CFLAGS contain -march=i686, the runtime will be built
both for i386 and i686. For any other value, only i386 variant will be
built.
Differential Revision: https://reviews.llvm.org/D26764
llvm-svn: 311924
Remove the explicit i686 target that is completely duplicate to
the i386 target, with the latter being used more commonly.
1. The runtime built for i686 will be identical to the one built for
i386.
2. Supporting both -i386 and -i686 suffixes causes unnecessary confusion
on the clang end which has to expect either of them.
3. The checks are based on wrong assumption that __i686__ is defined for
all newer x86 CPUs. In fact, it is only declared when -march=i686 is
explicitly used. It is not available when a more specific (or newer)
-march is used.
Curious enough, if CFLAGS contain -march=i686, the runtime will be built
both for i386 and i686. For any other value, only i386 variant will be
built.
Differential Revision: https://reviews.llvm.org/D26764
llvm-svn: 311842
Summary:
Adding ARM64 as a supported architecture for Scudo.
The random shuffle is not yet supported for SizeClassAllocator32, which is used
by the AArch64 allocator, so disable the associated test for now.
Reviewers: kcc, alekseyshl, rengolin
Reviewed By: rengolin
Subscribers: aemerson, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D28960
llvm-svn: 293068
Summary:
With the previous modifications, the code works on ARM32. The random shuffle
test is unsupported on 32-bit platforms for the moment and being marked as
such. There is no hardware support for the checksum computation yet, this will
come at a later point.
Reviewers: kcc, alekseyshl
Subscribers: llvm-commits, aemerson, rengolin, mgorny
Differential Revision: https://reviews.llvm.org/D27957
llvm-svn: 290201
Summary:
This update introduces i386 support for the Scudo Hardened Allocator, and
offers software alternatives for functions that used to require hardware
specific instruction sets. This should make porting to new architectures
easier.
Among the changes:
- The chunk header has been changed to accomodate the size limitations
encountered on 32-bit architectures. We now fit everything in 64-bit. This
was achieved by storing the amount of unused bytes in an allocation rather
than the size itself, as one can be deduced from the other with the help
of the GetActuallyAllocatedSize function. As it turns out, this header can
be used for both 64 and 32 bit, and as such we dropped the requirement for
the 128-bit compare and exchange instruction support (cmpxchg16b).
- Add 32-bit support for the checksum and the PRNG functions: if the SSE 4.2
instruction set is supported, use the 32-bit CRC32 instruction, and in the
XorShift128, use a 32-bit based state instead of 64-bit.
- Add software support for CRC32: if SSE 4.2 is not supported, fallback on a
software implementation.
- Modify tests that were not 32-bit compliant, and expand them to cover more
allocation and alignment sizes. The random shuffle test has been deactivated
for linux-i386 & linux-i686 as the 32-bit sanitizer allocator doesn't
currently randomize chunks.
Reviewers: alekseyshl, kcc
Subscribers: filcab, llvm-commits, tberghammer, danalbert, srhines, mgorny, modocache
Differential Revision: https://reviews.llvm.org/D26358
llvm-svn: 288255
Mitch Phillips