Summary:
For some reasons on Chromium when we start leak checking we get own pid as 1.
After that we see threads with PPID:0 assuming that thread is dead in infinite
loop.
To resolve particularly this case and possible issues like this, when IsAlive check failed to detect thread status, we need to limit the number of SuspendAllThreads
iterations.
Reviewers: eugenis
Subscribers: kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D46852
llvm-svn: 332319
Summary:
This is part of the larger XRay Profiling Mode effort.
This patch implements a central data structure for capturing statistics
about XRay instrumented function call stacks. The `FunctionCallTrie`
type does the following things:
* It keeps track of a shadow function call stack of XRay instrumented
functions as they are entered (function enter event) and as they are
exited (function exit event).
* When a function is entered, the shadow stack contains information
about the entry TSC, and updates the trie (or prefix tree)
representing the current function call stack. If we haven't
encountered this function call before, this creates a unique node for
the function in this position on the stack. We update the list of
callees of the parent function as well to reflect this newly found
path.
* When a function is exited, we compute statistics (TSC deltas,
function call count frequency) for the associated function(s) up the
stack as we unwind to find the matching entry event.
This builds upon the XRay `Allocator` and `Array` types in Part 1 of
this series of patches.
Depends on D45756.
Reviewers: echristo, pelikan, kpw
Reviewed By: kpw
Subscribers: llvm-commits, mgorny
Differential Revision: https://reviews.llvm.org/D45757
llvm-svn: 332313
Summary:
This change allows for handling the in-memory data associated with the
FDR mode implementation through the new `__xray_log_process_buffers`
API. With this change, we can now allow users to process the data
in-memory of the process instead of through writing files.
This for example allows users to stream the data of the FDR logging
implementation through network sockets, or through other mechanisms
instead of saving them to local files.
We introduce an FDR-specific flag, for "no_file_flush" which lets the
flushing logic skip opening/writing to files.
This option can be defaulted to `true` when building the compiler-rt
XRay runtime through the `XRAY_FDR_OPTIONS` preprocessor macro.
Reviewers: kpw, echristo, pelikan, eizan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46574
llvm-svn: 332208
Like Fuchsia, Myriad RTEMS uses an off-line symbolizer -- we just need
a custom backtrace frame string. Move this definition to
sanitizer_fuchsia.h; the corresponding RTEMS one will be added when we
add sanitizer_rtems.h.
Differential Revision: https://reviews.llvm.org/D46462
llvm-svn: 332157
In Windows version 1803, the first instruction of ntdll!strchr is:
8a01 mov al,byte ptr [rcx]
This is the only needed change for this version as far as I can tell.
Differential Revision: https://reviews.llvm.org/D46458
llvm-svn: 332095
This appears to be a copy/paste artifact from `AddrIsInHighMem`. It was caught by Firefox's jit-tests on Win64.
Differential Revision: https://reviews.llvm.org/D46291
llvm-svn: 332092
Summary:
This feature is required for proper libFuzzer support.
Adding SI_NETBSD to the list of OSes, fixes breakage in several
libFuzzer tests. It has been debugged with aid from kcc@.
Sponsored by <The NetBSD Foundation>
Reviewers: joerg, vitalybuka, kcc
Reviewed By: vitalybuka
Subscribers: kubamracek, llvm-commits, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D46729
llvm-svn: 332051
Replace decltype(memcpy) with decltype(__asan_memcpy) because memcpy
has not been defined in any headers on RTEMS. Similarly for memmove
and memset.
Differential Revision: https://reviews.llvm.org/D46625
llvm-svn: 332047
If detect-stack-use-after-return is on, initialize fake stack during
AsanThread::Init(), rather than lazily. This is required on Myriad.
From kcc: "There used to be a reason why this was done lazily, but I
don't remember if we still have that reason." Tested on x86.
Differential Revision: https://reviews.llvm.org/D46626
llvm-svn: 332033
Summary:
Experimental data flow tracer for fuzz targets.
Allows to tell which bytes of the input affect which functions of the fuzz target.
We previously attempted to use DFSan directly in the libFuzzer process,
and that didn't work nicely.
Now we will try to collect the data flow information for the seed corpus
in a separate process (using this tracer), and then use it in the regular libFuzzer runs.
Reviewers: morehouse, pcc, Dor1s
Reviewed By: morehouse, Dor1s
Subscribers: delcypher, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D46666
llvm-svn: 332029
Summary:
Fixed two non-standard usages of sem_open in the libFuzzer library and
one NetBSD-related modification with test script.
- The return value to indicate error should be SEM_FAILED instead of
(void *)-1 (please refer to "RETURN VALUE" section in this [[
http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_open.html
| page ]]). Actually, SEM_FAILED != (void *)-1 holds in NetBSD.
- The SharedMemoryRegion::SemName function should return name
starting with slash. Because the behaviour of name which does not
start with slash is unspecified as the [[
http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_open.html
| "DESCRIPTION" section ]] specified:
> If name does not begin with the <slash> character, the effect is implementation-defined.
- The length of name is limited to 14 in NetBSD, it is suggested to
reduce the length of equivalence server name in the test script.
Patch by: Yang Zheng
Reviewers: vitalybuka, krytarowski, kcc
Reviewed By: kcc
Subscribers: kcc, #sanitizers, llvm-commits, joerg
Differential Revision: https://reviews.llvm.org/D46622
llvm-svn: 332003
Summary:
Enumerating /proc/<pid>/task/ dir Linux may stop if thread is dead. In this case
we miss some alive threads and can report false memory leaks.
To solve this issue we repeat enumeration if the last thread is dead.
Do detect dead threads same way as proc_task_readdir we use
/proc/<pid>/task/<tid>/status.
Similarly it also ends enumeration of if proc_fill_cache fails, but in this case
Linux sets inode to 1 (Bad block).
And just in case re-list threads if we had to call internal_getdents more than
twice or result takes more than half of the buffer.
Reviewers: eugenis, dvyukov, glider
Subscribers: llvm-commits, kubamracek
Differential Revision: https://reviews.llvm.org/D46517
llvm-svn: 331953
Summary:
Leak checker needs to suspend all process threads. If we have some running
thread in registry but not suspended we can have false leak report. So we will
report this case here for future debugging.
Reviewers: eugenis
Subscribers: kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D46663
llvm-svn: 331936
Fuchsia is no longer treated as UNIX which means we need to explicitly
enable building of shared versions of runtimes.
Differential Revision: https://reviews.llvm.org/D46609
llvm-svn: 331922
Summary:
I think there might be something to optimize in `atomic_store`.
Currently, if everything goes well (and we have a different new value), we
always iterate 3 times.
For example, `with a = 0`, `oldval = a`, `newval = 42`, we get:
```
oldval = 0, newval = 42, curval = 0
oldval = 0, newval = 42, curval = 42
oldval = 42, newval = 42, curval = 42
```
and then it breaks.
Unless I am not seeing something, I don't see a point to the third iteration.
If the current value is the one we want, we should just break.
This means that 2 iterations (with a different newval) should be sufficient to
achieve what we want.
Reviewers: dvyukov, alekseyshl
Reviewed By: dvyukov
Subscribers: kubamracek, delcypher, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D46597
llvm-svn: 331890
Summary:
When out-of-memory or timeout occurs, threads can be stopped during
symbolization, thereby causing a deadlock when the OOM/TO handlers
attempt symbolization. We avoid this deadlock by skipping symbolization
if another thread is symbolizing.
Reviewers: kcc
Reviewed By: kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46605
llvm-svn: 331825
This change adds some assembler comments to facilitate analysis with
llvm-mca. In particular, we're interested in identifying and later
optimising (reducing) the cost of the key functions in the XRay
implementation using both static analysis (with llvm-mca, etc.) and
dynamic analysis (perf profiling, etc.) of microbenchmarks.
llvm-svn: 331711
Vitaly Buka