Commit Graph

4 Commits

Author SHA1 Message Date
Mitch Phillips 7339ca278c [GWP-ASan] Add generic unwinders and structure backtrace output.
Summary:
Adds two flavours of generic unwinder and all the supporting cruft. If the
supporting allocator is okay with bringing in sanitizer_common, they can use
the fast frame-pointer based unwinder from sanitizer_common. Otherwise, we also
provide the backtrace() libc-based unwinder as well. Of course, the allocator
can always specify its own unwinder and unwinder-symbolizer.

The slightly changed output format is exemplified in the first comment on this
patch. It now better incorporates backtrace information, and displays
allocation details on the second line.

Reviewers: eugenis, vlad.tsyrklevich

Reviewed By: eugenis, vlad.tsyrklevich

Subscribers: srhines, kubamracek, mgorny, cryptoad, #sanitizers, llvm-commits, morehouse

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D63841

llvm-svn: 364941
2019-07-02 16:04:52 +00:00
Mitch Phillips 05d1a2bd1b [GWP-ASan] Guard against recursive allocs. Pack TLS for perf.
Summary:
Add a recursivity guard for GPA::allocate(). This means that any
recursive allocations will fall back to the supporting allocator. In future
patches, we will introduce stack trace collection support. The unwinder will be
provided by the supporting allocator, and we can't guarantee they don't call
malloc() (e.g. backtrace() on posix may call dlopen(), which may call malloc().

Furthermore, this patch packs the new TLS recursivity guard into a thread local
struct, so that TLS variables should be hopefully not fall across cache lines.

Reviewers: vlad.tsyrklevich, morehouse, eugenis

Reviewed By: eugenis

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

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D63736

llvm-svn: 364356
2019-06-25 22:29:05 +00:00
Douglas Yung dbceb9b220 Fixup files added in r362636 to build with gcc 5.4. NFCI
llvm-svn: 362682
2019-06-06 08:04:33 +00:00
Mitch Phillips a95edb9dc1 [GWP-ASan] Core Guarded Pool Allocator [4].
Summary:
See D60593 for further information.

This patch introduces the core of GWP-ASan, being the guarded pool allocator. This class contains the logic for creating and maintaining allocations in the guarded pool. Its public interface is to be utilised by supporting allocators in order to provide sampled guarded allocation behaviour.

This patch also contains basic functionality tests of the allocator as unittests. The error-catching behaviour will be tested in upcoming patches that use Scudo as an implementing allocator.

Reviewers: vlad.tsyrklevich, eugenis, jfb

Reviewed By: vlad.tsyrklevich

Subscribers: dexonsmith, kubamracek, mgorny, cryptoad, jfb, #sanitizers, llvm-commits, morehouse

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D62872

llvm-svn: 362636
2019-06-05 19:42:48 +00:00