Summary:
With the recent move of `android_commands` to `sanitizer_common`, some things
have to be updated with regard to Scudo on Android.
Notably:
- `config.android` is dealt with in the common code
- `config.compile_wrapper` can be prepended to allow for the use of the android
commands
- `SCUDO_OPTIONS` must be passed with the environment when running a test
- `preinit.cpp` fails with some API levels, not sure why, I will have to dig
into this later.
Note that `check-scudo` is not enabled yet in the bots. It's all local testing
for now until everything looks good.
Reviewers: alekseyshl, vitalybuka
Reviewed By: vitalybuka
Subscribers: srhines, kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D37990
llvm-svn: 313561
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
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
Summary:
This is an initial implementation of a Hardened Allocator based on Sanitizer Common's CombinedAllocator.
It aims at mitigating heap based vulnerabilities by adding several features to the base allocator, while staying relatively fast.
The following were implemented:
- additional consistency checks on the allocation function parameters and on the heap chunks;
- use of checksum protected chunk header, to detect corruption;
- randomness to the allocator base;
- delayed freelist (quarantine), to mitigate use after free and overall determinism.
Additional mitigations are in the works.
Reviewers: eugenis, aizatsky, pcc, krasin, vitalybuka, glider, dvyukov, kcc
Subscribers: kubabrecka, filcab, llvm-commits
Differential Revision: http://reviews.llvm.org/D20084
llvm-svn: 271968
Kostya Kortchinsky