linux: Use INTERNAL_SYSCALL on fstatat{64}

Although not required by the standards, some code expects that a
successful stat call should not set errno.  However since aa03f722f3b99
'linux: Add {f}stat{at} y2038 support', on 32-bit systems with 32-bit
time_t supporrt, stat implementation will first issues __NR_statx and
if it fails with ENOSYS issue the system stat syscall.

On architecture running on kernel without __NR_statx support the
first call will set the errno to ENOSYS, even when the following stat
syscall might not fail.

This patch fixes by using INTERNAL_SYSCALL and only setting the errno
value when function returns.

Checked on i686-linux-gnu, x86_64-linux-gnu, sparc64-linux-gnu,
sparcv9-linux-gnu, powerpc64-linux-gnu, powerpc64le-linux-gnu,
arm-linux-gnueabihf, and aarch64-linux-gnu.

1 files changed, 17 insertions, 14 deletions

diff --git a/sysdeps/unix/sysv/linux/fstatat64.c b/sysdeps/unix/sysv/linux/fstatat64.c
index ae8fc101c5..44347603b4 100644
--- a/sysdeps/unix/sysv/linux/fstatat64.c
+++ b/sysdeps/unix/sysv/linux/fstatat64.c
@@ -39,31 +39,32 @@ __fstatat64_time64 (int fd, const char *file, struct __stat64_t64 *buf,
   /* 32-bit kABI with default 64-bit time_t, e.g. arc, riscv32.   Also
      64-bit time_t support is done through statx syscall.  */
   struct statx tmp;
-  r = INLINE_SYSCALL_CALL (statx, fd, file, AT_NO_AUTOMOUNT | flag,
-			   STATX_BASIC_STATS, &tmp);
-  if (r == 0 || errno != ENOSYS)
+  r = INTERNAL_SYSCALL_CALL (statx, fd, file, AT_NO_AUTOMOUNT | flag,
+			     STATX_BASIC_STATS, &tmp);
+  if (r == 0)
     {
-      if (r == 0)
-	__cp_stat64_t64_statx (buf, &tmp);
-      return r;
+      __cp_stat64_t64_statx (buf, &tmp);
+      return 0;
     }
+  if (-r != ENOSYS)
+    return INLINE_SYSCALL_ERROR_RETURN_VALUE (-r);
 #endif
 
 #if XSTAT_IS_XSTAT64
 # ifdef __NR_newfstatat
   /* 64-bit kABI, e.g. aarch64, ia64, powerpc64*, s390x, riscv64, and
      x86_64.  */
-  r = INLINE_SYSCALL_CALL (newfstatat, fd, file, buf, flag);
+  r = INTERNAL_SYSCALL_CALL (newfstatat, fd, file, buf, flag);
 # elif defined __NR_fstatat64
 #  if STAT64_IS_KERNEL_STAT64
   /* 64-bit kABI outlier, e.g. alpha  */
-  r = INLINE_SYSCALL_CALL (fstatat64, fd, file, buf, flag);
+  r = INTERNAL_SYSCALL_CALL (fstatat64, fd, file, buf, flag);
 #  else
   /* 64-bit kABI outlier, e.g. sparc64.  */
   struct kernel_stat64 kst64;
-  r = INLINE_SYSCALL_CALL (fstatat64, fd, file, &kst64, flag);
+  r = INTERNAL_SYSCALL_CALL (fstatat64, fd, file, &kst64, flag);
   if (r == 0)
-    r = __cp_stat64_kstat64 (buf, &kst64);
+    __cp_stat64_kstat64 (buf, &kst64);
 #  endif
 # endif
 #else
@@ -72,7 +73,7 @@ __fstatat64_time64 (int fd, const char *file, struct __stat64_t64 *buf,
      e.g. arm, csky, i386, hppa, m68k, microblaze, nios2, sh, powerpc32,
      and sparc32.  */
   struct stat64 st64;
-  r = INLINE_SYSCALL_CALL (fstatat64, fd, file, &st64, flag);
+  r = INTERNAL_SYSCALL_CALL (fstatat64, fd, file, &st64, flag);
   if (r == 0)
     {
       /* Clear both pad and reserved fields.  */
@@ -95,13 +96,15 @@ __fstatat64_time64 (int fd, const char *file, struct __stat64_t64 *buf,
 # else
   /* 64-bit kabi outlier, e.g. mips64 and mips64-n32.  */
   struct kernel_stat kst;
-  r = INLINE_SYSCALL_CALL (newfstatat, fd, file, &kst, flag);
+  r = INTERNAL_SYSCALL_CALL (newfstatat, fd, file, &kst, flag);
   if (r == 0)
-    r =  __cp_kstat_stat64_t64 (&kst, buf);
+    __cp_kstat_stat64_t64 (&kst, buf);
 # endif
 #endif
 
-  return r;
+  return INTERNAL_SYSCALL_ERROR_P (r)
+	 ? INLINE_SYSCALL_ERROR_RETURN_VALUE (-r)
+	 : 0;
 }
 #if __TIMESIZE != 64
 hidden_def (__fstatat64_time64)