Handle NetBSD specific indirection of libpthread functions

Summary:
Correct handling of three libpthread(3) functions on NetBSD:

 - pthread_mutex_lock(3),
 - pthread_mutex_unlock(3),
 - pthread_setcancelstate(3).

Code out of the libpthread(3) context uses the libc symbols:

 - __libc_mutex_lock,
 - __libc_mutex_unlock,
 - __libc_thr_setcancelstate.

The threading library (libpthread(3)) defines strong aliases:

 - __strong_alias(__libc_mutex_lock,pthread_mutex_lock)
 - __strong_alias(__libc_mutex_unlock,pthread_mutex_unlock)
 - __strong_alias(__libc_thr_setcancelstate,pthread_setcancelstate)

This caused that these functions were invisible to sanitizers on NetBSD.
Intercept the libc-specific ones and add them as NetBSD-specific aliases
for the common pthread(3) ones.

NetBSD needs to intercept both functions, as the regularly named ones
are used internally in libpthread(3).

Sponsored by <The NetBSD Foundation>

Reviewers: joerg, dvyukov, vitalybuka

Reviewed By: dvyukov

Subscribers: llvm-commits, kubamracek, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D40241

llvm-svn: 318646

1 files changed, 15 insertions, 0 deletions

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
index 16cc070206d..efe86977538 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
@@ -3828,6 +3828,15 @@ INTERCEPTOR(int, pthread_mutex_unlock, void *m) {
 #define INIT_PTHREAD_MUTEX_UNLOCK
 #endif
 
+#if SANITIZER_NETBSD
+INTERCEPTOR(void, __libc_mutex_lock, void *m) \
+  ALIAS(WRAPPER_NAME(pthread_mutex_lock));
+INTERCEPTOR(void, __libc_mutex_unlock, void *m) \
+  ALIAS(WRAPPER_NAME(pthread_mutex_unlock));
+INTERCEPTOR(void, __libc_thr_setcancelstate, int state, int *oldstate) \
+  ALIAS(WRAPPER_NAME(pthread_setcancelstate));
+#endif
+
 #if SANITIZER_INTERCEPT_GETMNTENT || SANITIZER_INTERCEPT_GETMNTENT_R
 static void write_mntent(void *ctx, __sanitizer_mntent *mnt) {
   COMMON_INTERCEPTOR_WRITE_RANGE(ctx, mnt, sizeof(*mnt));
@@ -6471,4 +6480,10 @@ static void InitializeCommonInterceptors() {
   INIT_GETLOADAVG;
   INIT_WCSLEN;
   INIT_WCSCAT;
+
+#if SANITIZER_NETBSD
+  COMMON_INTERCEPT_FUNCTION(__libc_mutex_lock);
+  COMMON_INTERCEPT_FUNCTION(__libc_mutex_unlock);
+  COMMON_INTERCEPT_FUNCTION(__libc_thr_setcancelstate);
+#endif
 }