Now that everything is forcibly linker initialized, it feels like a
good time to get rid of the `init`/`initLinkerInitialized` split.
This allows to get rid of various `memset` construct in `init` that
gcc complains about (this fixes a Fuchsia open issue).
I added various `DCHECK`s to ensure that we would get a zero-inited
object when entering `init`, which required ensuring that
`unmapTestOnly` leaves the object in a good state (tests are currently
the only location where an allocator can be "de-initialized").
Running the tests with `--gtest_repeat=` showed no issue.
Differential Revision: https://reviews.llvm.org/D103119
This patch does a few cleanup things:
1. The non-standalone scudo has a problem where GWP-ASan allocations
may not meet alignment requirements where Scudo was requested to have
alignment >= 16. Use the new GWP-ASan API to fix this.
2. The standalone variant loses some debugging information inside of
GWP-ASan because we ask GWP-ASan to allocate an aligned size in the
frontend. This means reports end up with 'UaF on a 16-byte allocation'
for a 1-byte allocation with 16-byte alignment. Also use the new API to
fix this.
3. Add post-alloc hooks for GWP-ASan intercepted allocations, and add
stats tracking for GWP-ASan allocations.
4. Add a small test that checks the alignment of the frontend
allocator, so that it can be used under GWP-ASan torture mode.
5. Add GWP-ASan torture mode as a testing configuration to catch these
regressions.
Depends on D94830, D95889.
Reviewed By: cryptoad
Differential Revision: https://reviews.llvm.org/D95884
Summary:
Fuchsia's gcc uses this, which in turn prevents us to compile successfully
due to a few `memset`'ing some non-trivial classes in some `init`.
Change those `memset` to members initialization.
Reviewers: pcc, hctim
Subscribers: #sanitizers, llvm-commits
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D77902
Summary:
fork() wasn't well (or at all) supported in Scudo. This materialized
in deadlocks in children.
In order to properly support fork, we will lock the allocator pre-fork
and unlock it post-fork in parent and child. This is done via a
`pthread_atfork` call installing the necessary handlers.
A couple of things suck here: this function allocates - so this has to
be done post initialization as our init path is not reentrance, and it
doesn't allow for an extra pointer - so we can't pass the allocator we
are currently working with.
In order to work around this, I added a post-init template parameter
that gets executed once the allocator is initialized for the current
thread. Its job for the C wrappers is to install the atfork handlers.
I reorganized a bit the impacted area and added some tests, courtesy
of cferris@ that were deadlocking prior to this fix.
Subscribers: jfb, #sanitizers, llvm-commits
Tags: #sanitizers, #llvm
Differential Revision: https://reviews.llvm.org/D72470
Summary:
This is a clean patch using the last diff of D69265, but using git
instead of svn, since svn went ro and arc was making my life harded
than it needed to be.
I was going to introduce a couple more lists and realized that our
lists are currently a bit all over the place. While we have a singly
linked list type relatively well defined, we are using doubly linked
lists defined on the fly for the stats and for the secondary blocks.
This CL adds a doubly linked list object, reorganizing the singly list
one to extract as much of the common code as possible. We use this
new type in the stats and the secondary. We also reorganize the list
tests to benefit from this consolidation.
There are a few side effect changes such as using for iterator loops
that are, in my opinion, cleaner in a couple of places.
Reviewers: hctim, morehouse, pcc, cferris
Reviewed By: hctim
Subscribers: jfb, #sanitizers, llvm-commits
Tags: #sanitizers, #llvm
Differential Revision: https://reviews.llvm.org/D69516
Summary:
Android requires additional stats in mallinfo. While we can provide
right away the number of bytes mapped (Primary+Secondary), there was
no way to get the number of free bytes (only makes sense for the
Primary since the Secondary unmaps everything on deallocation).
An approximation could be `StatMapped - StatAllocated`, but since we
are mapping in `1<<17` increments for the 64-bit Primary, it's fairly
inaccurate.
So we introduce `StatFree` (note it's `Free`, not `Freed`!), which
keeps track of the amount of Primary blocks currently unallocated.
Reviewers: cferris, eugenis, vitalybuka, hctim, morehouse
Reviewed By: morehouse
Subscribers: delcypher, #sanitizers, llvm-commits
Tags: #llvm, #sanitizers
Differential Revision: https://reviews.llvm.org/D66112
llvm-svn: 368866
Summary:
We ran into a problem on Fuchsia where yielding threads would never
be deboosted, ultimately resulting in several threads spinning on the
same TSD, and no possibility for another thread to be scheduled,
dead-locking the process.
While this was fixed in Zircon, this lead to discussions about if
spinning without a break condition was a good decision, and settled on
a new hybrid model that would spin for a while then block.
Currently we are using a number of iterations for spinning that is
mostly arbitrary (based on sanitizer_common values), but this can
be tuned in the future.
Since we are touching `common.h`, we also use this change as a vehicle
for an Android optimization (the page size is fixed in Bionic, so use
a fixed value too).
Reviewers: morehouse, hctim, eugenis, dvyukov, vitalybuka
Reviewed By: hctim
Subscribers: srhines, delcypher, jfb, #sanitizers, llvm-commits
Tags: #llvm, #sanitizers
Differential Revision: https://reviews.llvm.org/D64358
llvm-svn: 365790
Summary:
This adds simple local & global stats classes to be used by the Primary
and Secondary, and associated test. Note that we don't need the strict
atomicity of the addition & subtraction (as is in sanitizer_common) so
we just use load & store.
Reviewers: morehouse, vitalybuka, eugenis, flowerhack, dmmoore415
Reviewed By: morehouse, vitalybuka
Subscribers: mgorny, delcypher, jfb, #sanitizers, llvm-commits
Tags: #llvm, #sanitizers
Differential Revision: https://reviews.llvm.org/D59031
llvm-svn: 355643
Kostya Kortchinsky