Commit Graph

16 Commits

Author SHA1 Message Date
Fangrui Song 261d6e05d5 [sanitizer] Simplify __sanitizer::BufferedStackTrace::UnwindImpl implementations
Intended to be NFC. D102046 relies on the refactoring for stack boundaries.
2021-05-13 21:26:31 -07:00
Nico Weber 0e92cbd6a6 Revert "[sanitizer] Simplify GetTls with dl_iterate_phdr on Linux"
This reverts commit ec575e3b0a.
Still doesn't work, see https://crbug.com/1196037
2021-04-05 19:00:18 -04:00
Fangrui Song ec575e3b0a [sanitizer] Simplify GetTls with dl_iterate_phdr on Linux
This was reverted by f176803ef1 due to
Ubuntu 16.04 x86-64 glibc 2.23 problems.
This commit additionally calls `__tls_get_addr({modid,0})` to work around the
dlpi_tls_data==NULL issues for glibc<2.25
(https://sourceware.org/bugzilla/show_bug.cgi?id=19826)

GetTls is the range of

* thread control block and optional TLS_PRE_TCB_SIZE
* static TLS blocks plus static TLS surplus

On glibc, lsan requires the range to include
`pthread::{specific_1stblock,specific}` so that allocations only referenced by
`pthread_setspecific` can be scanned.

This patch uses `dl_iterate_phdr` to collect TLS blocks. Find the one
with `dlpi_tls_modid==1` as one of the initially loaded module, then find
consecutive ranges. The boundaries give us addr and size.

This allows us to drop the glibc internal `_dl_get_tls_static_info` and
`InitTlsSize` entirely. Use the simplified method with non-Android Linux for
now, but in theory this can be used with *BSD and potentially other ELF OSes.

This simplification enables D99566 for TLS Variant I architectures.

See https://reviews.llvm.org/D93972#2480556 for analysis on GetTls usage
across various sanitizers.

Differential Revision: https://reviews.llvm.org/D98926
2021-04-04 15:35:53 -07:00
Nico Weber f176803ef1 Revert "[sanitizer] Simplify GetTls with dl_iterate_phdr"
This reverts commit 9be8f8b34d.
This breaks tsan on Ubuntu 16.04:

    $ cat tiny_race.c
    #include <pthread.h>
    int Global;
    void *Thread1(void *x) {
      Global = 42;
      return x;
    }
    int main() {
      pthread_t t;
      pthread_create(&t, NULL, Thread1, NULL);
      Global = 43;
      pthread_join(t, NULL);
      return Global;
    }
    $ out/gn/bin/clang -fsanitize=thread -g -O1 tiny_race.c --sysroot ~/src/chrome/src/build/linux/debian_sid_amd64-sysroot/
    $ docker run -v $PWD:/foo ubuntu:xenial /foo/a.out
    FATAL: ThreadSanitizer CHECK failed: ../../compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp:447 "((thr_beg)) >= ((tls_addr))" (0x7fddd76beb80, 0xfffffffffffff980)
        #0 <null> <null> (a.out+0x4960b6)
        #1 <null> <null> (a.out+0x4b677f)
        #2 <null> <null> (a.out+0x49cf94)
        #3 <null> <null> (a.out+0x499bd2)
        #4 <null> <null> (a.out+0x42aaf1)
        #5 <null> <null> (libpthread.so.0+0x76b9)
        #6 <null> <null> (libc.so.6+0x1074dc)

(Get the sysroot from here: https://commondatastorage.googleapis.com/chrome-linux-sysroot/toolchain/500976182686961e34974ea7bdc0a21fca32be06/debian_sid_amd64_sysroot.tar.xz)

Also reverts follow-on commits:
This reverts commit 58c62fd976.
This reverts commit 31e541e375.
2021-04-02 18:19:17 -04:00
Fangrui Song 9be8f8b34d [sanitizer] Simplify GetTls with dl_iterate_phdr
GetTls is the range of

* thread control block and optional TLS_PRE_TCB_SIZE
* static TLS blocks plus static TLS surplus

On glibc, lsan requires the range to include
`pthread::{specific_1stblock,specific}` so that allocations only referenced by
`pthread_setspecific` can be scanned.

This patch uses `dl_iterate_phdr` to collect TLS ranges. Find the one
with `dlpi_tls_modid==1` as one of the initially loaded module, then find
consecutive ranges. The boundaries give us addr and size.

This allows us to drop the glibc internal `_dl_get_tls_static_info` and
`InitTlsSize` entirely. Use the simplified method with non-Android Linux for
now, but in theory this can be used with *BSD and potentially other ELF OSes.

In the future, we can move `ThreadDescriptorSize` code to lsan (and consider
intercepting `pthread_setspecific`) to avoid hacks in generic code.

See https://reviews.llvm.org/D93972#2480556 for analysis on GetTls usage
across various sanitizers.

Differential Revision: https://reviews.llvm.org/D98926
2021-03-25 21:55:27 -07:00
Vitaly Buka 60913ebcbc [NFC][LSAN] Use InitializeCommonFlags in LSAN 2020-10-21 01:41:52 -07:00
Nikita Popov f161e84c10 Revert "[lsan] On Fuchsia, don't use atexit hook for leak checks"
This reverts commit 0caad9fe44.
This reverts commit c96d0cceb6.

Causes linker errors which were not fixed by the subsequent commit
either:

/home/nikic/llvm-project/compiler-rt/lib/asan/asan_rtl.cpp:503: error: undefined reference to '__asan::InstallAtExitCheckLeaks()'
2020-09-23 21:10:56 +02:00
Roland McGrath 0caad9fe44 [lsan] On Fuchsia, don't use atexit hook for leak checks
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, phosek

Differential Revision: https://reviews.llvm.org/D86171
2020-09-23 11:10:58 -07:00
Fangrui Song 2d7fd38cf7 [sanitizers] Remove unneeded MaybeCall*DefaultOptions() and nullptr checks
D28596 added SANITIZER_INTERFACE_WEAK_DEF which can guarantee `*_default_options` are always defined.
The weak attributes on the `__{asan,lsan,msan,ubsan}_default_options` declarations can thus be removed.

`MaybeCall*DefaultOptions` no longer need nullptr checks, so their call sites can just be replaced by `__*_default_options`.

Reviewed By: #sanitizers, vitalybuka

Differential Revision: https://reviews.llvm.org/D87175
2020-09-08 10:12:05 -07:00
Roland McGrath 90a10f00ff [lsan] Support LeakSanitizer runtime on Fuchsia
Support LeakSanitizer runtime on Fuchsia.

Patch By: mcgrathr

Differential Revision: https://reviews.llvm.org/D72887
2020-01-28 11:34:53 -08:00
Petr Hosek 2533bc2361 Revert "[lsan] Support LeakSanitizer runtime on Fuchsia"
This reverts commit d59e3429f3.
2020-01-28 00:24:41 -08:00
Roland McGrath d59e3429f3 [lsan] Support LeakSanitizer runtime on Fuchsia
Support LeakSanitizer runtime on Fuchsia.

Patch By: mcgrathr

Differential Revision: https://reviews.llvm.org/D72887
2020-01-27 23:35:06 -08:00
Roland McGrath 38fd1806a1 [lsan] Factor pthread-specific assumptions out of thread tracking code
This is a small refactoring to prepare for porting LSan to Fuchsia.
Factor out parts of lsan_thread.{cpp,h} that don't apply to Fuchsia.
Since existing supported systems are POSIX-based, the affected code
is moved to lsan_posix.{cpp.h}.

Patch By: mcgrathr

Differential Revision: https://reviews.llvm.org/D73309
2020-01-24 16:55:11 -08:00
Vitaly Buka d39e7e2cf1 [compiler-rt] Use GetNextInstructionPc in signal handlers
Summary:
All other stack trace callers assume that PC contains return address.
HWAsan already use GetNextInstructionPc in similar code.

PR43339

Reviewers: eugenis, kcc, jfb

Subscribers: dexonsmith, dberris, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D68313

llvm-svn: 373529
2019-10-02 21:20:37 +00:00
Vitaly Buka c0fa632236 Remove NOLINTs from compiler-rt
llvm-svn: 371687
2019-09-11 23:19:48 +00:00
Nico Weber ae1fc9baae compiler-rt: Rename .cc file in lib/lsan to .cpp
Like r367463, but for lsan.

llvm-svn: 367561
2019-08-01 14:01:30 +00:00