[tsan] Refine fstat{,64} interceptors (#86625)

MaskRay · llvmbot · commit f249092ef26d · 2024-04-01T22:10:23.000Z
In glibc versions before 2.33. `libc_nonshared.a` defines `__fxstat/__fxstat64` but there is no `fstat/fstat64`. glibc 2.33 added `fstat/fstat64` and obsoleted `__fxstat/__fxstat64`. Ports added after 2.33 do not provide `__fxstat/__fxstat64`, so our `fstat/fstat64` interceptors using `__fxstat/__fxstat64` interceptors would lead to runtime failures on such ports (LoongArch and certain RISC-V ports). Similar to https://reviews.llvm.org/D118423, refine the conditions that we define fstat{,64} interceptors. `fstat` is supported by musl/*BSD while `fstat64` is glibc only. (cherry picked from commit d5224b7)
diff --git a/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp b/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp
@@ -14,6 +14,7 @@
 
 #include "sanitizer_common/sanitizer_atomic.h"
 #include "sanitizer_common/sanitizer_errno.h"
+#include "sanitizer_common/sanitizer_glibc_version.h"
 #include "sanitizer_common/sanitizer_libc.h"
 #include "sanitizer_common/sanitizer_linux.h"
 #include "sanitizer_common/sanitizer_platform_limits_netbsd.h"
@@ -1613,47 +1614,40 @@ TSAN_INTERCEPTOR(int, __fxstat, int version, int fd, void *buf) {
     FdAccess(thr, pc, fd);
   return REAL(__fxstat)(version, fd, buf);
 }
-#define TSAN_MAYBE_INTERCEPT___FXSTAT TSAN_INTERCEPT(__fxstat)
+
+TSAN_INTERCEPTOR(int, __fxstat64, int version, int fd, void *buf) {
+  SCOPED_TSAN_INTERCEPTOR(__fxstat64, version, fd, buf);
+  if (fd > 0)
+    FdAccess(thr, pc, fd);
+  return REAL(__fxstat64)(version, fd, buf);
+}
+#define TSAN_MAYBE_INTERCEPT___FXSTAT TSAN_INTERCEPT(__fxstat); TSAN_INTERCEPT(__fxstat64)
 #else
 #define TSAN_MAYBE_INTERCEPT___FXSTAT
 #endif
 
+#if !SANITIZER_GLIBC || __GLIBC_PREREQ(2, 33)
 TSAN_INTERCEPTOR(int, fstat, int fd, void *buf) {
-#if SANITIZER_GLIBC
-  SCOPED_TSAN_INTERCEPTOR(__fxstat, 0, fd, buf);
-  if (fd > 0)
-    FdAccess(thr, pc, fd);
-  return REAL(__fxstat)(0, fd, buf);
-#else
   SCOPED_TSAN_INTERCEPTOR(fstat, fd, buf);
   if (fd > 0)
     FdAccess(thr, pc, fd);
   return REAL(fstat)(fd, buf);
-#endif
-}
-
-#if SANITIZER_GLIBC
-TSAN_INTERCEPTOR(int, __fxstat64, int version, int fd, void *buf) {
-  SCOPED_TSAN_INTERCEPTOR(__fxstat64, version, fd, buf);
-  if (fd > 0)
-    FdAccess(thr, pc, fd);
-  return REAL(__fxstat64)(version, fd, buf);
 }
-#define TSAN_MAYBE_INTERCEPT___FXSTAT64 TSAN_INTERCEPT(__fxstat64)
+#  define TSAN_MAYBE_INTERCEPT_FSTAT TSAN_INTERCEPT(fstat)
 #else
-#define TSAN_MAYBE_INTERCEPT___FXSTAT64
+#  define TSAN_MAYBE_INTERCEPT_FSTAT
 #endif
 
-#if SANITIZER_GLIBC
+#if __GLIBC_PREREQ(2, 33)
 TSAN_INTERCEPTOR(int, fstat64, int fd, void *buf) {
-  SCOPED_TSAN_INTERCEPTOR(__fxstat64, 0, fd, buf);
+  SCOPED_TSAN_INTERCEPTOR(fstat64, fd, buf);
   if (fd > 0)
     FdAccess(thr, pc, fd);
-  return REAL(__fxstat64)(0, fd, buf);
+  return REAL(fstat64)(fd, buf);
 }
-#define TSAN_MAYBE_INTERCEPT_FSTAT64 TSAN_INTERCEPT(fstat64)
+#  define TSAN_MAYBE_INTERCEPT_FSTAT64 TSAN_INTERCEPT(fstat64)
 #else
-#define TSAN_MAYBE_INTERCEPT_FSTAT64
+#  define TSAN_MAYBE_INTERCEPT_FSTAT64
 #endif
 
 TSAN_INTERCEPTOR(int, open, const char *name, int oflag, ...) {
@@ -2950,10 +2944,9 @@ void InitializeInterceptors() {
 
   TSAN_INTERCEPT(pthread_once);
 
-  TSAN_INTERCEPT(fstat);
   TSAN_MAYBE_INTERCEPT___FXSTAT;
+  TSAN_MAYBE_INTERCEPT_FSTAT;
   TSAN_MAYBE_INTERCEPT_FSTAT64;
-  TSAN_MAYBE_INTERCEPT___FXSTAT64;
   TSAN_INTERCEPT(open);
   TSAN_MAYBE_INTERCEPT_OPEN64;
   TSAN_INTERCEPT(creat);
