Summary:
Make SizeClassAllocator32 return nullptr when it encounters OOM, which
allows the entire sanitizer's allocator to follow allocator_may_return_null=1
policy, even for small allocations (LargeMmapAllocator is already fixed
by D34243).
Will add a test for OOM in primary allocator later, when
SizeClassAllocator64 can gracefully handle OOM too.
Reviewers: eugenis
Subscribers: kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D34433
llvm-svn: 305972
Summary:
AFAICT compiler-rt doesn't have a function that would return 'good' random
bytes to seed a PRNG. Currently, the `SizeClassAllocator64` uses addresses
returned by `mmap` to seed its PRNG, which is not ideal, and
`SizeClassAllocator32` doesn't benefit from the entropy offered by its 64-bit
counterpart address space, so right now it has nothing. This function aims at
solving this, allowing to implement good 32-bit chunk randomization. Scudo also
has a function that does this for Cookie purposes, which would go away in a
later CL once this lands.
This function will try the `getrandom` syscall if available, and fallback to
`/dev/urandom` if not.
Unfortunately, I do not have a way to implement and test a Mac and Windows
version, so those are unimplemented as of now. Note that `kRandomShuffleChunks`
is only used on Linux for now.
Reviewers: alekseyshl
Reviewed By: alekseyshl
Subscribers: zturner, rnk, llvm-commits, kubamracek
Differential Revision: https://reviews.llvm.org/D34412
llvm-svn: 305922
Summary:
This broke thread_local_quarantine_pthread_join.cc on some architectures, due
to the overhead of the stashed regions. Reverting while figuring out the best
way to deal with it.
Reviewers: alekseyshl
Reviewed By: alekseyshl
Subscribers: llvm-commits, kubamracek
Differential Revision: https://reviews.llvm.org/D34213
llvm-svn: 305404
Summary:
The reasoning behind this change is explained in D33454, which unfortunately
broke the Windows version (due to the platform not supporting partial unmapping
of a memory region).
This new approach changes `MmapAlignedOrDie` to allow for the specification of
a `padding_chunk`. If non-null, and the initial allocation is aligned, this
padding chunk will hold the address of the extra memory (of `alignment` bytes).
This allows `AllocateRegion` to get 2 regions if the memory is aligned
properly, and thus help reduce fragmentation (and saves on unmapping
operations). As with the initial D33454, we use a stash in the 32-bit Primary
to hold those extra regions and return them on the fast-path.
The Windows version of `MmapAlignedOrDie` will always return a 0
`padding_chunk` if one was requested.
Reviewers: alekseyshl, dvyukov, kcc
Reviewed By: alekseyshl
Subscribers: llvm-commits, kubamracek
Differential Revision: https://reviews.llvm.org/D34152
llvm-svn: 305391
Summary: The new name better corresponds to its logic.
Reviewers: kcc
Subscribers: kubabrecka
Differential Revision: https://reviews.llvm.org/D26821
llvm-svn: 287377
When ASan currently detects a bug, by default it will only print out the text
of the report to stderr. This patch changes this behavior and writes the full
text of the report to syslog before we terminate the process. It also calls
os_trace (Activity Tracing available on OS X and iOS) with a message saying
that the report is available in syslog. This is useful, because this message
will be shown in the crash log.
For this to work, the patch makes sure we store the full report into
error_message_buffer unconditionally, and it also strips out ANSI escape
sequences from the report (they are used when producing colored reports).
I've initially tried to log to syslog during printing, which is done on Android
right now. The advantage is that if we crash during error reporting or the
produced error does not go through ScopedInErrorReport, we would still get a
(partial) message in the syslog. However, that solution is very problematic on
OS X. One issue is that the logging routine uses GCD, which may spawn a new
thread on its behalf. In many cases, the reporting logic locks threadRegistry,
which leads to deadlocks.
Reviewed at http://reviews.llvm.org/D13452
(In addition, add sanitizer_common_libcdep.cc to buildgo.sh to avoid
build failures on Linux.)
llvm-svn: 253688
When ASan currently detects a bug, by default it will only print out the text
of the report to stderr. This patch changes this behavior and writes the full
text of the report to syslog before we terminate the process. It also calls
os_trace (Activity Tracing available on OS X and iOS) with a message saying
that the report is available in syslog. This is useful, because this message
will be shown in the crash log.
For this to work, the patch makes sure we store the full report into
error_message_buffer unconditionally, and it also strips out ANSI escape
sequences from the report (they are used when producing colored reports).
I've initially tried to log to syslog during printing, which is done on Android
right now. The advantage is that if we crash during error reporting or the
produced error does not go through ScopedInErrorReport, we would still get a
(partial) message in the syslog. However, that solution is very problematic on
OS X. One issue is that the logging routine uses GCD, which may spawn a new
thread on its behalf. In many cases, the reporting logic locks threadRegistry,
which leads to deadlocks.
Reviewed at http://reviews.llvm.org/D13452
(In addition, add sanitizer_common_libcdep.cc to buildgo.sh to avoid
build failures on Linux.)
llvm-svn: 251577
When ASan currently detects a bug, by default it will only print out the text
of the report to stderr. This patch changes this behavior and writes the full
text of the report to syslog before we terminate the process. It also calls
os_trace (Activity Tracing available on OS X and iOS) with a message saying
that the report is available in syslog. This is useful, because this message
will be shown in the crash log.
For this to work, the patch makes sure we store the full report into
error_message_buffer unconditionally, and it also strips out ANSI escape
sequences from the report (they are used when producing colored reports).
I've initially tried to log to syslog during printing, which is done on Android
right now. The advantage is that if we crash during error reporting or the
produced error does not go through ScopedInErrorReport, we would still get a
(partial) message in the syslog. However, that solution is very problematic on
OS X. One issue is that the logging routine uses GCD, which may spawn a new
thread on its behalf. In many cases, the reporting logic locks threadRegistry,
which leads to deadlocks.
Reviewed at http://reviews.llvm.org/D13452
llvm-svn: 251447
Summary: These are needed to talk to llvm-symbolizer on Windows.
Reviewers: samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11920
llvm-svn: 244533
Summary:
This commit introduces function __sanitizer::RenderFrame()
that allows to render the contents of AddressInfo (essentially, symbolized stack frame)
using the custom format string. This function can be used to
implement stack frame formatting for both ThreadSanitizer and
generic StackTrace::Print(), used in another places. This paves the
way towards allowing user to control the format of stack frames,
obtaining them in any format he desires, and/or enforcing the consistent
output from all sanitizers.
Test Plan: compiler-rt test suite
Reviewers: kcc
Reviewed By: kcc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6140
llvm-svn: 221409
This reduces the number of "write" syscalls performed to print a single
stack frame description, and makes sanitizer output less intermixed with
program output. Also, add a number of unit tests.
llvm-svn: 194686
Move this function to sanitizer_common because LSan uses it too. Also, fix a bug
where the TLS range reported for main thread was off by the size of the thread
descriptor from libc (TSan doesn't care much, but for LSan it's critical).
llvm-svn: 181322
Alex Shlyapnikov