commit 2a3224c53653214cbba2ec23424702193c80ea3b
Author: Siddhesh Poyarekar <siddhesh@sourceware.org>
Date:   Wed Dec 30 11:09:58 2020 +0530

    string: Enable __FORTIFY_LEVEL=3
    
    This change enhances fortified string functions to use
    __builtin_dynamic_object_size under _FORTIFY_SOURCE=3 whenever the
    compiler supports it.

# Conflicts:
#	string/bits/string_fortified.h

Conflict resolved to retain __GNUC_PREREQ (5,0) macro check in RHEL-8
glibc.

diff --git a/include/string.h b/include/string.h
index 4d622f1c0305e78e..bbc97082661caf42 100644
--- a/include/string.h
+++ b/include/string.h
@@ -119,10 +119,11 @@ libc_hidden_proto (__ffs)
 void __explicit_bzero_chk_internal (void *, size_t, size_t)
   __THROW __nonnull ((1)) attribute_hidden;
 # define explicit_bzero(buf, len) \
-  __explicit_bzero_chk_internal (buf, len, __bos0 (buf))
+  __explicit_bzero_chk_internal (buf, len, __glibc_objsize0 (buf))
 #elif !IS_IN (nonlib)
 void __explicit_bzero_chk (void *, size_t, size_t) __THROW __nonnull ((1));
-# define explicit_bzero(buf, len) __explicit_bzero_chk (buf, len, __bos0 (buf))
+# define explicit_bzero(buf, len) __explicit_bzero_chk (buf, len,	      \
+							__glibc_objsize0 (buf))
 #endif
 
 libc_hidden_builtin_proto (memchr)
diff --git a/string/bits/string_fortified.h b/string/bits/string_fortified.h
index 4ed6755a6c1ca247..27ec273ec41cd81c 100644
--- a/string/bits/string_fortified.h
+++ b/string/bits/string_fortified.h
@@ -31,13 +31,15 @@ __fortify_function void *
 __NTH (memcpy (void *__restrict __dest, const void *__restrict __src,
 	       size_t __len))
 {
-  return __builtin___memcpy_chk (__dest, __src, __len, __bos0 (__dest));
+  return __builtin___memcpy_chk (__dest, __src, __len,
+				 __glibc_objsize0 (__dest));
 }
 
 __fortify_function void *
 __NTH (memmove (void *__dest, const void *__src, size_t __len))
 {
-  return __builtin___memmove_chk (__dest, __src, __len, __bos0 (__dest));
+  return __builtin___memmove_chk (__dest, __src, __len,
+				  __glibc_objsize0 (__dest));
 }
 
 #ifdef __USE_GNU
@@ -45,7 +47,8 @@ __fortify_function void *
 __NTH (mempcpy (void *__restrict __dest, const void *__restrict __src,
 		size_t __len))
 {
-  return __builtin___mempcpy_chk (__dest, __src, __len, __bos0 (__dest));
+  return __builtin___mempcpy_chk (__dest, __src, __len,
+				  __glibc_objsize0 (__dest));
 }
 #endif
 
@@ -68,7 +71,8 @@ __NTH (memset (void *__dest, int __ch, size_t __len))
       return __dest;
     }
 #endif
-  return __builtin___memset_chk (__dest, __ch, __len, __bos0 (__dest));
+  return __builtin___memset_chk (__dest, __ch, __len,
+				 __glibc_objsize0 (__dest));
 }
 
 #ifdef __USE_MISC
@@ -80,21 +84,21 @@ void __explicit_bzero_chk (void *__dest, size_t __len, size_t __destlen)
 __fortify_function void
 __NTH (explicit_bzero (void *__dest, size_t __len))
 {
-  __explicit_bzero_chk (__dest, __len, __bos0 (__dest));
+  __explicit_bzero_chk (__dest, __len, __glibc_objsize0 (__dest));
 }
 #endif
 
 __fortify_function char *
 __NTH (strcpy (char *__restrict __dest, const char *__restrict __src))
 {
-  return __builtin___strcpy_chk (__dest, __src, __bos (__dest));
+  return __builtin___strcpy_chk (__dest, __src, __glibc_objsize (__dest));
 }
 
 #ifdef __USE_GNU
 __fortify_function char *
 __NTH (stpcpy (char *__restrict __dest, const char *__restrict __src))
 {
-  return __builtin___stpcpy_chk (__dest, __src, __bos (__dest));
+  return __builtin___stpcpy_chk (__dest, __src, __glibc_objsize (__dest));
 }
 #endif
 
@@ -103,14 +107,16 @@ __fortify_function char *
 __NTH (strncpy (char *__restrict __dest, const char *__restrict __src,
 		size_t __len))
 {
-  return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
+  return __builtin___strncpy_chk (__dest, __src, __len,
+				  __glibc_objsize (__dest));
 }
 
 #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, __bos (__dest));
+  return __builtin___stpncpy_chk (__dest, __src, __n,
+				  __glibc_objsize (__dest));
 }
 #else
 extern char *__stpncpy_chk (char *__dest, const char *__src, size_t __n,
@@ -132,7 +138,7 @@ __NTH (stpncpy (char *__dest, const char *__src, size_t __n))
 __fortify_function char *
 __NTH (strcat (char *__restrict __dest, const char *__restrict __src))
 {
-  return __builtin___strcat_chk (__dest, __src, __bos (__dest));
+  return __builtin___strcat_chk (__dest, __src, __glibc_objsize (__dest));
 }
 
 
@@ -140,7 +146,8 @@ __fortify_function char *
 __NTH (strncat (char *__restrict __dest, const char *__restrict __src,
 		size_t __len))
 {
-  return __builtin___strncat_chk (__dest, __src, __len, __bos (__dest));
+  return __builtin___strncat_chk (__dest, __src, __len,
+				  __glibc_objsize (__dest));
 }
 
 #endif /* bits/string_fortified.h */
diff --git a/string/bits/strings_fortified.h b/string/bits/strings_fortified.h
index d9b2804525cfa994..871515bd2cba1f8a 100644
--- a/string/bits/strings_fortified.h
+++ b/string/bits/strings_fortified.h
@@ -22,13 +22,15 @@
 __fortify_function void
 __NTH (bcopy (const void *__src, void *__dest, size_t __len))
 {
-  (void) __builtin___memmove_chk (__dest, __src, __len, __bos0 (__dest));
+  (void) __builtin___memmove_chk (__dest, __src, __len,
+				  __glibc_objsize0 (__dest));
 }
 
 __fortify_function void
 __NTH (bzero (void *__dest, size_t __len))
 {
-  (void) __builtin___memset_chk (__dest, '\0', __len, __bos0 (__dest));
+  (void) __builtin___memset_chk (__dest, '\0', __len,
+				 __glibc_objsize0 (__dest));
 }
 
 #endif