Commit Graph

13 Commits

Author SHA1 Message Date
Evgeniy Stepanov 4f0e10fff9 [hwasan] Add a (almost) no-interceptor mode.
Summary:
The idea behind this change is to allow sanitization of libc. We are prototyping on Bionic,
but the tool interface will be general enough (or at least generalizable) to support any other libc.

When libc depends on libclang_rt.hwasan, the latter can not interpose libc functions.
In fact, majority of interceptors become unnecessary when libc code is instrumented.

This change gets rid of most hwasan interceptors and provides interface for libc to notify
hwasan about thread creation and destruction events. Some interceptors (pthread_create)
are kept under #ifdef to enable testing with uninstrumented libc. They are expressed in
terms of the new libc interface.

The new cmake switch, COMPILER_RT_HWASAN_WITH_INTERCEPTORS, ON by default, builds testing
version of the library with the aforementioned pthread_create interceptor.
With the OFF setting, the library becomes more of a libc plugin.

Reviewers: vitalybuka, kcc, jfb

Subscribers: srhines, kubamracek, mgorny, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D50922

llvm-svn: 340216
2018-08-20 21:49:15 +00:00
Evgeniy Stepanov 37fb896572 Revert "Revert "[hwasan] Add __hwasan_handle_longjmp.""
This reapplies commit r339935 with the following changes:
* make longjmp test C, not C++, to avoid dependency on libc++/libstdc++
* untag pointer in memset interceptor

x86_64 does not have TBI, so hwasan barely works there. Tests must be carefully
written in a way that does not leak tagged pointer to system libraries.

llvm-svn: 339963
2018-08-16 23:17:14 +00:00
Evgeniy Stepanov d8cc7f9f07 [hwasan] Provide __sanitizer_* aliases to allocator functions.
Summary:
Export __sanitizer_malloc, etc as aliases to malloc, etc.
This way users can wrap sanitizer malloc, even in fully static binaries.

Both jemalloc and tcmalloc provide similar aliases (je_* and tc_*).

Reviewers: vitalybuka, kcc

Subscribers: llvm-commits, kubamracek

Differential Revision: https://reviews.llvm.org/D50570

llvm-svn: 339614
2018-08-13 21:07:27 +00:00
Alex Shlyapnikov af12729185 [HWASan] Report proper error on allocator failures instead of CHECK(0)-ing
Summary:
Currently many allocator specific errors (OOM, for example) are reported as
a text message and CHECK(0) termination, not stack, no details, not too
helpful nor informative. To improve the situation, detailed and
structured errors were defined and reported under the appropriate conditions.

Reviewers: eugenis

Subscribers: kubamracek, delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D47798

llvm-svn: 334248
2018-06-07 23:33:33 +00:00
Alex Shlyapnikov 79866cad6f [HWASan] Introduce non-zero based and dynamic shadow memory (compiler-rt).
Retire the fixed shadow memory mapping to avoid conflicts with default
process memory mapping (currently manifests on Android).

Tests on AArch64 show <1% performance loss and code size increase,
making it possible to use dynamic shadow memory by default.

Keep the fixed shadow memory mapping around to be able to run
performance comparison tests later.

Re-commiting D45847 with fixed shadow for x86-64.

llvm-svn: 330624
2018-04-23 18:19:23 +00:00
Reid Kleckner 061fcd586d Revert r330474 - "[HWASan] Introduce non-zero based and dynamic shadow memory (compiler-rt)."
This commit causes internal errors with ld.bfd 2.24. My guess is that
the ifunc usage in this commit is causing problems. This is the default
system linker on Trusty Tahr, which is from 2014. I claim it's still in
our support window. Maybe we will decide to drop support for it, but
let's get the bots green while we do the investigation and have that
discussion.

Discovered here: https://crbug.com/835864

llvm-svn: 330619
2018-04-23 17:26:33 +00:00
Alex Shlyapnikov c3ec1643f1 [HWASan] Introduce non-zero based and dynamic shadow memory (compiler-rt).
Summary:
Retire the fixed shadow memory mapping to avoid conflicts with default
process memory mapping (currently manifests on Android).

Tests on AArch64 show <1% performance loss and code size increase,
making it possible to use dynamic shadow memory by default.

For the simplicity and unifirmity sake, use dynamic shadow memory mapping
with base address accessed via ifunc resolver on all supported platforms.

Keep the fixed shadow memory mapping around to be able to run
performance comparison tests later.

Complementing D45840.

Reviewers: eugenis

Subscribers: srhines, kubamracek, dberris, mgorny, kristof.beyls, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D45847

llvm-svn: 330474
2018-04-20 20:03:57 +00:00
Alex Shlyapnikov 5cd35ed4fe [HWASan] Port HWASan to Linux x86-64 (compiler-rt)
Summary:
Porting HWASan to Linux x86-64, first of the three patches, compiler-rt part.

The approach is similar to ARM case, trap signal is used to communicate
memory tag check failure. int3 instruction is used to generate a signal,
access parameters are stored in nop [eax + offset] instruction immediately
following the int3 one

Had to add HWASan init on malloc because, due to much less interceptors
defined (most other sanitizers intercept much more and get initalized
via one of those interceptors or don't care about malloc), HWASan was not
initialized yet when libstdc++ was trying to allocate memory for its own
fixed-size heap, which led to CHECK-fail in AllocateFromLocalPool.

Also added the CHECK() failure handler with more detailed message and
stack reporting.

Reviewers: eugenis

Subscribers: kubamracek, dberris, mgorny, kristof.beyls, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D44705

llvm-svn: 328385
2018-03-23 23:38:04 +00:00
George Burgess IV de772ce015 Attempt to appease buildbots
I can't reproduce this build error locally, but it appears
straightforward enough to fix. r326851 renamed two of the params of this
interceptor, but apparently to update their use here.

Failure:
http://lab.llvm.org:8011/builders/clang-cmake-aarch64-full/builds/4569

llvm-svn: 326876
2018-03-07 07:36:23 +00:00
Vitaly Buka 78457e68f4 [sanitizer] Move mmap interceptors into sanitizer_common
Reviewers: devnexen, krytarowski, eugenis

Subscribers: kubamracek, llvm-commits

Differential Revision: https://reviews.llvm.org/D44125

llvm-svn: 326851
2018-03-07 00:13:54 +00:00
Kamil Rytarowski 39628a7ab0 Add NetBSD syscall hooks skeleton in sanitizers
Summary:
Implement the skeleton of NetBSD syscall hooks for use with sanitizers.

Add a script that generates the rules to handle syscalls
on NetBSD: generate_netbsd_syscalls.awk. It has been written
in NetBSD awk(1) (patched nawk) and is compatible with gawk.

Generate lib/sanitizer_common/sanitizer_platform_limits_netbsd.h
that is a public header for applications, and included as:
<sanitizer_common/sanitizer_platform_limits_netbsd.h>.

Generate sanitizer_syscalls_netbsd.inc that defines all the
syscall rules for NetBSD. This file is modeled after the Linux
specific file: sanitizer_common_syscalls.inc.

Start recognizing NetBSD syscalls with existing sanitizers:
ASan, ESan, HWASan, TSan, MSan.

Sponsored by <The NetBSD Foundation>

Reviewers: joerg, vitalybuka, kcc, dvyukov, eugenis

Reviewed By: vitalybuka

Subscribers: hintonda, kubamracek, mgorny, llvm-commits, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D42048

llvm-svn: 325206
2018-02-15 02:43:02 +00:00
Evgeniy Stepanov 99fa3e774d [hwasan] Stack instrumentation.
Summary:
Very basic stack instrumentation using tagged pointers.
Tag for N'th alloca in a function is built as XOR of:
 * base tag for the function, which is just some bits of SP (poor
   man's random)
 * small constant which is a function of N.

Allocas are aligned to 16 bytes. On every ReturnInst allocas are
re-tagged to catch use-after-return.

This implementation has a bunch of issues that will be taken care of
later:
1. lifetime intrinsics referring to tagged pointers are not
   recognized in SDAG. This effectively disables stack coloring.
2. Generated code is quite inefficient. There is one extra
   instruction at each memory access that adds the base tag to the
   untagged alloca address. It would be better to keep tagged SP in a
   callee-saved register and address allocas as an offset of that XOR
   retag, but that needs better coordination between hwasan
   instrumentation pass and prologue/epilogue insertion.
3. Lifetime instrinsics are ignored and use-after-scope is not
   implemented. This would be harder to do than in ASan, because we
   need to use a differently tagged pointer depending on which
   lifetime.start / lifetime.end the current instruction is dominated
   / post-dominated.

Reviewers: kcc, alekseyshl

Subscribers: srhines, kubamracek, javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D41602

llvm-svn: 322324
2018-01-11 22:53:30 +00:00
Evgeniy Stepanov 9595d16893 Hardware-assisted AddressSanitizer (compiler-rt)
Summary:
Runtime library for HWASan, initial commit.
Does not randomize tags yet, does not handle stack or globals.

Reviewers: kcc, pcc, alekseyshl

Subscribers: srhines, kubamracek, dberris, mgorny, llvm-commits, krytarowski

Differential Revision: https://reviews.llvm.org/D40935

llvm-svn: 320231
2017-12-09 01:31:51 +00:00