As shown in https://github.com/llvm/llvm-project/issues/42932 dead
pointers might be overlapped by a new stack frame inside CheckForLeaks,
which does not use bytes with pointers. This leads to false negatives.
It's not a full solution for the problem as it does not solve
"overlapping" new/old frames for frames below the CheckForLeaks and in
other threads. It should improve leaks found in direct callers of
__lsan_do_leak_check.
Differential Revision: https://reviews.llvm.org/D130237
libdispatch uses its own heap (_dispatch_main_heap) for some allocations, including the dispatch_continuation_t that holds a dispatch source's event handler.
Objective-C block trampolines (creating methods at runtime with a block as the implementations) use the VM_MEMORY_FOUNDATION region (see 8701d5672d/runtime/objc-block-trampolines.mm (L371)).
This change scans both regions to fix false positives. See tests for details; unfortunately I was unable to reduce the trampoline example with imp_implementationWithBlock on a new class, so I'm resorting to something close to the bug as seen in the wild.
Differential Revision: https://reviews.llvm.org/D129385
Detailed motivation here: https://docs.google.com/document/d/1xUNo5ovPKJMYxitiHUQVRxGI3iUmspI51Jm4w8puMwo
check-asan (with LSAN enabled) and check-lsan are currently broken on recent macOS versions, due to pervasive false positives. Whenever the Objective-C runtime realizes a class, it allocates data for it, then stores that data with flags in the low bits. This means LSAN can not recognize it as a pointer while scanning.
This change checks every potential pointer on Apple platforms, and if the high bit is set, attempts to extract a pointer by masking out the high bit and flags. This is ugly, but it's also the best approach I could think of (see doc above); very open to other suggestions.
Differential Revision: https://reviews.llvm.org/D133126
This is a follow up to [Sanitizers][Darwin] Rename Apple macro SANITIZER_MAC -> SANITIZER_APPLE (D125816)
Performed a global search/replace as in title against LLVM sources
Differential Revision: https://reviews.llvm.org/D126263
While attempting to get the 64-bit lsan allocator working for Fuchsia, I
noticed this function would incorrectly return false for pointers returned
by the 64-bit allocator. On AArch64, this function attempts to get the VMA
size dynamically by counting the number of leading zeros from the function
frame address. This will fail if the frame address is significantly below an
allocated pointer (that is, the frame address has more leading zeros than an
allocated pointer). This is possible on Fuchsia and linux (when not called
from the initial thread stack).
It seems the intended use of this function is to speed up pointer scanning by
filtering out addresses that user code might not be able to access. Other
platforms this check is done on seem to hardcode the VMA size/shift, so it
seems appropriate to do this for aarch64 as well. This implies pointers on
aarch64 where the VMA size is <64 will pass through, but bad pointers will
still be caught by subsequent scan checks.
This patch also renames the function to something more fitting of what it's
trying to do.
Differential Revision: https://reviews.llvm.org/D123814
This is a re-land of https://reviews.llvm.org/D86171 with fix.
Fuchsia's system libraries are instrumented and use the lsan
allocator for internal purposes. So leak checking needs to run
after all atexit hooks and after the system libraries' internal
exit-time hooks. The <zircon/sanitizer.h> hook API calls the
__sanitizer_process_exit_hook function at exactly the right time.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D88248
If sanitizer cannot determine name of the module it
will use "<unknown module>". Then it can be suppressed
if needed.
Reviewed By: kda
Differential Revision: https://reviews.llvm.org/D121674
For ppc64 PIE, it seems that [0xa00000000000,0xc00000000000) may be occupied
which will lead to a segfault in certain kernel configurations
(clang-ppc64le-rhel). Use the `!kUsingConstantSpaceBeg` code path like Fuchsia.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D121257
This is a follow up to 4f3f4d672254
("sanitizer_common: fix __sanitizer_get_module_and_offset_for_pc signature mismatch")
which fixes a similar problem for msan build.
I am getting the following error compiling a unit test for code that
uses sanitizer_common headers and googletest transitively includes
sanitizer interface headers:
In file included from third_party/gwp_sanitizers/singlestep_test.cpp:3:
In file included from sanitizer_common/sanitizer_common.h:19:
sanitizer_interface_internal.h:41:5: error: typedef redefinition with different types
('struct __sanitizer_sandbox_arguments' vs 'struct __sanitizer_sandbox_arguments')
} __sanitizer_sandbox_arguments;
common_interface_defs.h:39:3: note: previous definition is here
} __sanitizer_sandbox_arguments;
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D119546
Currently we use very common names for macros like ACQUIRE/RELEASE,
which cause conflicts with system headers.
Prefix all macros with SANITIZER_ to avoid conflicts.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D116652
This removes the last use of StackDepot from StopTheWorld.
Depends on D115284.
Reviewed By: morehouse
Differential Revision: https://reviews.llvm.org/D115319
StackDepot locks some stuff. As is there is small probability to
deadlock if we stop thread which locked the Depot.
We need either Lock/Unlock StackDepot for StopTheWorld, or don't
interact with StackDepot from there.
This patch does not run LeakReport under StopTheWorld. LeakReport
contains most of StackDepot access.
As a bonus this patch will help to resolve kMaxLeaksConsidered FIXME.
Depends on D114498.
Reviewed By: morehouse, kstoimenov
Differential Revision: https://reviews.llvm.org/D115284
kIgnored didn't exist when the code was added, but it should be
equivalent to kReachable.
The goal is to refactor MarkInvalidPCCb to avoid StackDepotGet
in StopTheWorld.
It is required for the [Leak Sanitizer port to Windows](https://reviews.llvm.org/D115103).
The currently used `unsigned long` type is 64 bits wide on UNIX like systems but only 32 bits wide on Windows.
Because of that, the literal `8UL << 30` causes an integer overflow on Windows.
By changing the type of the literals to `unsigned long long`, we have consistent behavior and no overflows on all Platforms.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D115186
It should be NFC, as they already intercept pthread_create.
This will let us to fix BackgroundThread for these sanitizerts.
In in followup patches I will fix MaybeStartBackgroudThread for them
and corresponding tests.
Reviewed By: kstoimenov
Differential Revision: https://reviews.llvm.org/D114935
They don't seem to do anything useful in lsan.
They are needed only if a tools needs to execute
some custom logic during detach/join, or if it uses
thread registry quarantine. Lsan does none of this.
And if a tool cares then it would also need to intercept
pthread_tryjoin_np and pthread_timedjoin_np, otherwise
it will mess thread states.
Fwiw, asan does not intercept these functions either.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D113920
Since glibc 2.34, dlsym does
1. malloc 1
2. malloc 2
3. free pointer from malloc 1
4. free pointer from malloc 2
These sequence was not handled by trivial dlsym hack.
This fixes https://bugs.llvm.org/show_bug.cgi?id=52278
Reviewed By: eugenis, morehouse
Differential Revision: https://reviews.llvm.org/D112588
Currently, SANITIZER_COMMON_SUPPORTED_OS is being used to enable many libraries.
Unfortunately this makes it impossible to selectively disable a library based on the OS.
This patch removes this limitation by adding a separate list of supported OSs for the lsan, ubsan, ubsan_minimal, and stats libraries.
Reviewed By: delcypher
Differential Revision: https://reviews.llvm.org/D113444
Enable -Wformat in sanitizer_common now that it's
cleaned up from existing warnings.
But disable it in all sanitizers for now since
they are not cleaned up yet, but inherit sanitizer_common CFLAGS.
Depends on D107980.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D107981
Mutex does not support LINKER_INITIALIZED support.
As preparation to switching BlockingMutex to Mutex,
proactively replace all BlockingMutex(LINKER_INITIALIZED) to Mutex.
All of these are objects with static storage duration and Mutex ctor
is constexpr, so it should be equivalent.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D106944
The current (default) line length is 80 columns.
That's based on old hardware and historical conventions.
There are no existent reasons to keep line length that small,
especially provided that our coding style uses quite lengthy
identifiers. The Linux kernel recently switched to 100,
let's start with 100 as well.
This change intentionally does not re-format code.
Re-formatting is intended to happen incrementally,
or on dir-by-dir basis separately.
Reviewed By: vitalybuka, melver, MaskRay
Differential Revision: https://reviews.llvm.org/D106436
Currently ThreadRegistry is overcomplicated because of tsan,
it needs tid quarantine and reuse counters. Other sanitizers
don't need that. It also seems that no other sanitizer now
needs max number of threads. Asan used to need 2^24 limit,
but it does not seem to be needed now. Other sanitizers blindly
copy-pasted that without reasons. Lsan also uses quarantine,
but I don't see why that may be potentially needed.
Add a ThreadRegistry ctor that does not require any sizes
and use it in all sanitizers except for tsan.
In preparation for new tsan runtime, which won't need
any of these parameters as well.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D105713
Enable clang Thread Safety Analysis for sanitizers:
https://clang.llvm.org/docs/ThreadSafetyAnalysis.html
Thread Safety Analysis can detect inconsistent locking,
deadlocks and data races. Without GUARDED_BY annotations
it has limited value. But this does all the heavy lifting
to enable analysis and allows to add GUARDED_BY incrementally.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D105716