Module Name: src
Committed By: kamil
Date: Fri Oct 2 14:36:54 UTC 2020
Modified Files:
src/external/gpl3/gcc/dist/libsanitizer/sanitizer_common:
sanitizer_linux_libcdep.cc
Log Message:
Do not assume that _lwp_getprivate() returns unbiased private pointer
Cherry-pick and adapt:
>From 2a9ce60de98e53198047daaeeec3cf09ece4e693 Mon Sep 17 00:00:00 2001
From: Kamil Rytarowski <n...@gmx.com>
Date: Fri, 2 Oct 2020 16:13:09 +0200
Subject: [PATCH] [compiler-rt] [netbsd] Improve the portability of
ThreadSelfTlsTcb
Use __lwp_gettcb_fast() and __lwp_getprivate_fast(), as _lwp_getprivate()
can be a biased pointer and invalid for use in this function on all CPUs.
To generate a diff of this commit:
cvs rdiff -u -r1.16 -r1.17 \
src/external/gpl3/gcc/dist/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/external/gpl3/gcc/dist/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc
diff -u src/external/gpl3/gcc/dist/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc:1.16 src/external/gpl3/gcc/dist/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc:1.17
--- src/external/gpl3/gcc/dist/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc:1.16 Thu Sep 10 12:53:05 2020
+++ src/external/gpl3/gcc/dist/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc Fri Oct 2 14:36:54 2020
@@ -25,6 +25,10 @@
#include "sanitizer_placement_new.h"
#include "sanitizer_procmaps.h"
+#if SANITIZER_NETBSD
+#define _RTLD_SOURCE // for __lwp_gettcb_fast() / __lwp_getprivate_fast()
+#endif
+
#include <dlfcn.h> // for dlsym()
#include <link.h>
#include <pthread.h>
@@ -418,7 +422,13 @@ uptr ThreadSelf() {
#if SANITIZER_NETBSD
static struct tls_tcb * ThreadSelfTlsTcb() {
- return (struct tls_tcb *)_lwp_getprivate();
+ struct tls_tcb *tcb = nullptr;
+#ifdef __HAVE___LWP_GETTCB_FAST
+ tcb = (struct tls_tcb *)__lwp_gettcb_fast();
+#elif defined(__HAVE___LWP_GETPRIVATE_FAST)
+ tcb = (struct tls_tcb *)__lwp_getprivate_fast();
+#endif
+ return tcb;
}
uptr ThreadSelf() {
