debug: Synchronize feature guards in fortified functions [BZ #28746]

Some functions (e.g. stpcpy, pread64, etc.) had moved to POSIX in the
main headers as they got incorporated into the standard, but their
fortified variants remained under __USE_GNU.  As a result, these
functions did not get fortified when _GNU_SOURCE was not defined.

Add test wrappers that check all functions tested in tst-chk0 at all
levels with _GNU_SOURCE undefined and then use the failures to (1)
exclude checks for _GNU_SOURCE functions in these tests and (2) Fix
feature macro guards in the fortified function headers so that they're
the same as the ones in the main headers.

This fixes BZ #28746.

Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

6 files changed, 58 insertions, 15 deletions

diff --git a/debug/Makefile b/debug/Makefile
index 8804776..96029f3 100644
--- a/debug/Makefile
+++ b/debug/Makefile
@@ -132,6 +132,12 @@ define cflags-lfs
 CFLAGS-tst-fortify-$(1)-lfs-$(2).$(1) += -D_FILE_OFFSET_BITS=64
 endef
 
+define cflags-nongnu
+CFLAGS-tst-fortify-$(1)-nongnu-$(2).$(1) += -D_LARGEFILE64_SOURCE=1
+endef
+
+src-chk-nongnu = \#undef _GNU_SOURCE
+
 # We know these tests have problems with format strings, this is what
 # we are testing.  Disable that warning.  They are also testing
 # deprecated functions (notably gets) so disable that warning as well.
@@ -145,13 +151,13 @@ CFLAGS-tst-fortify-$(1)-$(2)-$(3).$(1) += -D_FORTIFY_SOURCE=$(3) -Wno-format \
 $(eval $(call cflags-$(2),$(1),$(3)))
 $(objpfx)tst-fortify-$(1)-$(2)-$(3).$(1): tst-fortify.c Makefile
 	( echo "/* Autogenerated from Makefile.  */"; \
-	  echo ""; \
+	  echo "$(src-chk-$(2))"; \
 	  echo "#include \"tst-fortify.c\"" ) > $$@.tmp
 	mv $$@.tmp $$@
 endef
 
 chk-extensions = c cc
-chk-types = default lfs
+chk-types = default lfs nongnu
 chk-levels = 1 2 3
 
 $(foreach e,$(chk-extensions), \
diff --git a/debug/tst-fortify.c b/debug/tst-fortify.c
index 9288610..d65a2fe 100644
--- a/debug/tst-fortify.c
+++ b/debug/tst-fortify.c
@@ -1,4 +1,5 @@
 /* Copyright (C) 2004-2022 Free Software Foundation, Inc.
+   Copyright The GNU Toolchain Authors.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -36,6 +37,17 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 
+#ifndef _GNU_SOURCE
+# define MEMPCPY memcpy
+# define WMEMPCPY wmemcpy
+# define MEMPCPY_RET(x) 0
+# define WMEMPCPY_RET(x) 0
+#else
+# define MEMPCPY mempcpy
+# define WMEMPCPY wmempcpy
+# define MEMPCPY_RET(x) __builtin_strlen (x)
+# define WMEMPCPY_RET(x) wcslen (x)
+#endif
 
 #define obstack_chunk_alloc malloc
 #define obstack_chunk_free free
@@ -162,7 +174,7 @@ do_test (void)
   if (memcmp (buf, "aabcdefghi", 10))
     FAIL ();
 
-  if (mempcpy (buf + 5, "abcde", 5) != buf + 10
+  if (MEMPCPY (buf + 5, "abcde", 5) != buf + 5 + MEMPCPY_RET ("abcde")
       || memcmp (buf, "aabcdabcde", 10))
     FAIL ();
 
@@ -207,7 +219,7 @@ do_test (void)
   if (memcmp (buf, "aabcdefghi", 10))
     FAIL ();
 
-  if (mempcpy (buf + 5, "abcde", l0 + 5) != buf + 10
+  if (MEMPCPY (buf + 5, "abcde", l0 + 5) != buf + 5 + MEMPCPY_RET ("abcde")
       || memcmp (buf, "aabcdabcde", 10))
     FAIL ();
 
@@ -266,7 +278,8 @@ do_test (void)
   if (memcmp (a.buf1, "aabcdefghi", 10))
     FAIL ();
 
-  if (mempcpy (a.buf1 + 5, "abcde", l0 + 5) != a.buf1 + 10
+  if (MEMPCPY (a.buf1 + 5, "abcde", l0 + 5)
+      != a.buf1 + 5 + MEMPCPY_RET ("abcde")
       || memcmp (a.buf1, "aabcdabcde", 10))
     FAIL ();
 
@@ -347,6 +360,7 @@ do_test (void)
   bcopy (buf + 1, buf + 2, l0 + 9);
   CHK_FAIL_END
 
+#ifdef _GNU_SOURCE
   CHK_FAIL_START
   p = (char *) mempcpy (buf + 6, "abcde", 5);
   CHK_FAIL_END
@@ -354,6 +368,7 @@ do_test (void)
   CHK_FAIL_START
   p = (char *) mempcpy (buf + 6, "abcde", l0 + 5);
   CHK_FAIL_END
+#endif
 
   CHK_FAIL_START
   memset (buf + 9, 'j', 2);
@@ -464,6 +479,7 @@ do_test (void)
   bcopy (a.buf1 + 1, a.buf1 + 2, l0 + 9);
   CHK_FAIL_END
 
+#ifdef _GNU_SOURCE
   CHK_FAIL_START
   p = (char *) mempcpy (a.buf1 + 6, "abcde", 5);
   CHK_FAIL_END
@@ -471,6 +487,7 @@ do_test (void)
   CHK_FAIL_START
   p = (char *) mempcpy (a.buf1 + 6, "abcde", l0 + 5);
   CHK_FAIL_END
+#endif
 
   CHK_FAIL_START
   memset (a.buf1 + 9, 'j', 2);
@@ -550,7 +567,7 @@ do_test (void)
   if (wmemcmp (wbuf, L"aabcdefghi", 10))
     FAIL ();
 
-  if (wmempcpy (wbuf + 5, L"abcde", 5) != wbuf + 10
+  if (WMEMPCPY (wbuf + 5, L"abcde", 5) != wbuf + 5 + WMEMPCPY_RET (L"abcde")
       || wmemcmp (wbuf, L"aabcdabcde", 10))
     FAIL ();
 
@@ -583,7 +600,8 @@ do_test (void)
   if (wmemcmp (wbuf, L"aabcdefghi", 10))
     FAIL ();
 
-  if (wmempcpy (wbuf + 5, L"abcde", l0 + 5) != wbuf + 10
+  if (WMEMPCPY (wbuf + 5, L"abcde", l0 + 5)
+      != wbuf + 5 + WMEMPCPY_RET (L"abcde")
       || wmemcmp (wbuf, L"aabcdabcde", 10))
     FAIL ();
 
@@ -625,7 +643,8 @@ do_test (void)
   if (wmemcmp (wa.buf1, L"aabcdefghi", 10))
     FAIL ();
 
-  if (wmempcpy (wa.buf1 + 5, L"abcde", l0 + 5) != wa.buf1 + 10
+  if (WMEMPCPY (wa.buf1 + 5, L"abcde", l0 + 5)
+      != wa.buf1 + 5 + WMEMPCPY_RET (L"abcde")
       || wmemcmp (wa.buf1, L"aabcdabcde", 10))
     FAIL ();
 
@@ -694,6 +713,7 @@ do_test (void)
   wmemmove (wbuf + 2, wbuf + 1, l0 + 9);
   CHK_FAIL_END
 
+#ifdef _GNU_SOURCE
   CHK_FAIL_START
   wp = wmempcpy (wbuf + 6, L"abcde", 5);
   CHK_FAIL_END
@@ -701,6 +721,7 @@ do_test (void)
   CHK_FAIL_START
   wp = wmempcpy (wbuf + 6, L"abcde", l0 + 5);
   CHK_FAIL_END
+#endif
 
   CHK_FAIL_START
   wmemset (wbuf + 9, L'j', 2);
@@ -768,6 +789,7 @@ do_test (void)
   wmemmove (wa.buf1 + 2, wa.buf1 + 1, l0 + 9);
   CHK_FAIL_END
 
+#ifdef _GNU_SOURCE
   CHK_FAIL_START
   wp = wmempcpy (wa.buf1 + 6, L"abcde", 5);
   CHK_FAIL_END
@@ -775,6 +797,7 @@ do_test (void)
   CHK_FAIL_START
   wp = wmempcpy (wa.buf1 + 6, L"abcde", l0 + 5);
   CHK_FAIL_END
+#endif
 
   CHK_FAIL_START
   wmemset (wa.buf1 + 9, L'j', 2);
@@ -906,6 +929,7 @@ do_test (void)
   if (fprintf (fp, buf2 + 4, str5) != 7)
     FAIL ();
 
+#ifdef _GNU_SOURCE
   char *my_ptr = NULL;
   strcpy (buf2 + 2, "%n%s%n");
   /* When the format string is writable and contains %n,
@@ -935,6 +959,7 @@ do_test (void)
   if (obstack_printf (&obs, "%s%n%s%n", str4, &n1, str5, &n1) != 14)
     FAIL ();
   obstack_free (&obs, NULL);
+#endif
 
   if (freopen (temp_filename, "r", stdin) == NULL)
     {
@@ -982,6 +1007,7 @@ do_test (void)
 
   rewind (stdin);
 
+#ifdef _GNU_SOURCE
   if (fgets_unlocked (buf, buf_size, stdin) != buf
       || memcmp (buf, "abcdefgh\n", 10))
     FAIL ();
@@ -1008,6 +1034,7 @@ do_test (void)
 #endif
 
   rewind (stdin);
+#endif
 
   if (fread (buf, 1, buf_size, stdin) != buf_size
       || memcmp (buf, "abcdefgh\nA", 10))
@@ -1578,7 +1605,10 @@ do_test (void)
       ret = 1;
     }
 
-  int fd = posix_openpt (O_RDWR);
+  int fd;
+
+#ifdef _GNU_SOURCE
+  fd = posix_openpt (O_RDWR);
   if (fd != -1)
     {
       char enough[1000];
@@ -1594,6 +1624,7 @@ do_test (void)
 #endif
       close (fd);
     }
+#endif
 
 #if PATH_MAX > 0
   confstr (_CS_GNU_LIBC_VERSION, largebuf, sizeof (largebuf));
@@ -1711,8 +1742,9 @@ do_test (void)
   poll (fds, l0 + 2, 0);
   CHK_FAIL_END
 #endif
+#ifdef _GNU_SOURCE
   ppoll (fds, 1, NULL, NULL);
-#if __USE_FORTIFY_LEVEL >= 1
+# if __USE_FORTIFY_LEVEL >= 1
   CHK_FAIL_START
   ppoll (fds, 2, NULL, NULL);
   CHK_FAIL_END
@@ -1720,6 +1752,7 @@ do_test (void)
   CHK_FAIL_START
   ppoll (fds, l0 + 2, NULL, NULL);
   CHK_FAIL_END
+# endif
 #endif
 
   return ret;
diff --git a/posix/bits/unistd.h b/posix/bits/unistd.h
index 01df84b..f53a7a0 100644
--- a/posix/bits/unistd.h
+++ b/posix/bits/unistd.h
@@ -40,7 +40,7 @@ read (int __fd, void *__buf, size_t __nbytes)
 			  __fd, __buf, __nbytes);
 }
 
-#ifdef __USE_UNIX98
+#if defined __USE_UNIX98 || defined __USE_XOPEN2K8
 extern ssize_t __pread_chk (int __fd, void *__buf, size_t __nbytes,
 			    __off_t __offset, size_t __bufsize)
   __wur __attr_access ((__write_only__, 2, 3));
diff --git a/string/bits/string_fortified.h b/string/bits/string_fortified.h
index 51ad480..f4a5dfc 100644
--- a/string/bits/string_fortified.h
+++ b/string/bits/string_fortified.h
@@ -79,7 +79,7 @@ __NTH (strcpy (char *__restrict __dest, const char *__restrict __src))
   return __builtin___strcpy_chk (__dest, __src, __glibc_objsize (__dest));
 }
 
-#ifdef __USE_GNU
+#ifdef __USE_XOPEN2K8
 __fortify_function char *
 __NTH (stpcpy (char *__restrict __dest, const char *__restrict __src))
 {
@@ -96,14 +96,15 @@ __NTH (strncpy (char *__restrict __dest, const char *__restrict __src,
 				  __glibc_objsize (__dest));
 }
 
-#if __GNUC_PREREQ (4, 7) || __glibc_clang_prereq (2, 6)
+#ifdef __USE_XOPEN2K8
+# if __GNUC_PREREQ (4, 7) || __glibc_clang_prereq (2, 6)
 __fortify_function char *
 __NTH (stpncpy (char *__dest, const char *__src, size_t __n))
 {
   return __builtin___stpncpy_chk (__dest, __src, __n,
 				  __glibc_objsize (__dest));
 }
-#else
+# else
 extern char *__stpncpy_chk (char *__dest, const char *__src, size_t __n,
 			    size_t __destlen) __THROW
   __fortified_attr_access ((__write_only__, 1, 3))
@@ -119,6 +120,7 @@ __NTH (stpncpy (char *__dest, const char *__src, size_t __n))
     return __stpncpy_chk (__dest, __src, __n, __bos (__dest));
   return __stpncpy_alias (__dest, __src, __n);
 }
+# endif
 #endif
 
 
diff --git a/support/xsignal.h b/support/xsignal.h
index 973f532..d868bb3 100644
--- a/support/xsignal.h
+++ b/support/xsignal.h
@@ -28,7 +28,9 @@ __BEGIN_DECLS
    terminate the process on error.  */
 
 void xraise (int sig);
+#ifdef _GNU_SOURCE
 sighandler_t xsignal (int sig, sighandler_t handler);
+#endif
 void xsigaction (int sig, const struct sigaction *newact,
                  struct sigaction *oldact);
 
diff --git a/wcsmbs/bits/wchar2.h b/wcsmbs/bits/wchar2.h
index 25d06d4..0e017f4 100644
--- a/wcsmbs/bits/wchar2.h
+++ b/wcsmbs/bits/wchar2.h
@@ -457,7 +457,7 @@ __NTH (wcsrtombs (char *__restrict __dst, const wchar_t **__restrict __src,
 }
 
 
-#ifdef __USE_GNU
+#ifdef	__USE_XOPEN2K8
 extern size_t __mbsnrtowcs_chk (wchar_t *__restrict __dst,
 				const char **__restrict __src, size_t __nmc,
 				size_t __len, mbstate_t *__restrict __ps,