[llvm-branch-commits] [compiler-rt] release/18.x: [tsan] Refine fstat{, 64} interceptors (#86625) (PR #87286)

[via llvm-branch-commits]

https://github.com/llvmbot created https://github.com/llvm/llvm-project/pull/87286

Backport d5224b73ccd09a6759759791f58426b6acd4a2e2

Requested by: @MaskRay

>From f249092ef26d6fe9627b0158c7c15dee241226db Mon Sep 17 00:00:00 2001
From: Fangrui Song <i at maskray.me>
Date: Tue, 26 Mar 2024 14:09:39 -0700
Subject: [PATCH] [tsan] Refine fstat{,64} interceptors (#86625)

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 d5224b73ccd09a6759759791f58426b6acd4a2e2)
---
 .../lib/tsan/rtl/tsan_interceptors_posix.cpp  | 43 ++++++++-----------
 1 file changed, 18 insertions(+), 25 deletions(-)

diff --git a/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp b/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp
index a9f6673ac44e90..d0282c27043125 100644
--- 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);