This patch changes hwasan inline instrumentation:
Fixes address untagging for shadow address calculation (use 0xFF instead of 0x00 for the top byte).
Emits brk instruction instead of hlt for the kernel and user space.
Use 0x900 instead of 0x100 for brk immediate (0x100 - 0x800 are unavailable in the kernel).
Fixes and adds appropriate tests.
Patch by Andrey Konovalov.
Differential Revision: https://reviews.llvm.org/D43135
llvm-svn: 325711
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
Summary:
Make common allocator agnostic to failure handling modes and move the
decision up to the particular sanitizer's allocator, where the context
is available (call stack, parameters, return nullptr/crash mode etc.)
It simplifies the common allocator and allows the particular sanitizer's
allocator to generate more specific and detailed error reports (which
will be implemented later).
The behavior is largely the same, except one case, the violation of the
common allocator's check for "size + alignment" overflow is now reportied
as OOM instead of "bad request". It feels like a worthy tradeoff and
"size + alignment" is huge in this case anyway (thus, can be interpreted
as not enough memory to satisfy the request). There's also a Report()
statement added there.
Reviewers: eugenis
Subscribers: kubamracek, llvm-commits, #sanitizers
Differential Revision: https://reviews.llvm.org/D42198
llvm-svn: 322784
Summary: -fPIE can not be used when building a shared library.
Reviewers: alekseyshl, peter.smith
Subscribers: kubamracek, llvm-commits, mgorny
Differential Revision: https://reviews.llvm.org/D42121
llvm-svn: 322588
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
Summary:
Avoid flaky test failures by by using a monotonic number sequence of
heap tags.
Does not affect stack tags: the way we generate those guarantees
uniqueness for at least 30-something first allocas in any function,
as well as the UAR tag.
Reviewers: alekseyshl, kcc
Subscribers: llvm-commits, kubamracek
Differential Revision: https://reviews.llvm.org/D41882
llvm-svn: 322214
Summary: Very similar to AddressSanitizer, with the exception of the error type encoding.
Reviewers: kcc, alekseyshl
Subscribers: cfe-commits, kubamracek, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D41417
llvm-svn: 321203
Summary: This brings CPU overhead on bzip2 down from 5.5x to 2x.
Reviewers: kcc, alekseyshl
Subscribers: kubamracek, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D41137
llvm-svn: 320538
Vitaly Buka