From 6876672e67fb5e3a71139585ca4c16e43cfed70e Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Fri, 18 Aug 2017 12:27:59 -0700
Subject: [PATCH] Mark internal nss symbols with attribute_hidden [BZ #18822]

Mark internal nss symbols with attribute_hidden to allow direct access
within libc.so and libc.a without using GOT nor PLT.

Tested on x86-64 with and without --disable-nscd.

	[BZ #18822]
	* grp/initgroups.c (__nss_initgroups_database): Removed.
	* nss/XXX-lookup.c (DATABASE_NAME_SYMBOL): Likewise.
	* nss/getXXent.c (INTERNAL (REENTRANT_GETNAME)): Add
	attribute_hidden.
	* nss/nsswitch.c (__nss_database_custom): Define only if
	USE_NSCD is defined.
	(__nss_configure_lookup): Use __nss_database_custom only if
	USE_NSCD is defined.
	* nss/nsswitch.h (__nss_database_custom): Declare only if
	USE_NSCD is defined.  Add attribute_hidden.
	(__nss_setent): Add attribute_hidden.
	(__nss_endent): Likewise.
	(__nss_getent_r): Likewise.
	(__nss_getent): Likewise.
	(DEFINE_DATABASE): Declare __nss_##arg##_database.
---
 grp/initgroups.c |  1 -
 nss/XXX-lookup.c |  2 --
 nss/getXXent.c   |  2 +-
 nss/nsswitch.c   |  4 ++++
 nss/nsswitch.h   | 23 +++++++++++++++--------
 5 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/grp/initgroups.c b/grp/initgroups.c
index 0d5b841796..0ffb5ceea1 100644
--- a/grp/initgroups.c
+++ b/grp/initgroups.c
@@ -37,7 +37,6 @@ typedef enum nss_status (*initgroups_dyn_function) (const char *, gid_t,
 						    gid_t **, long int, int *);
 
 extern service_user *__nss_group_database attribute_hidden;
-service_user *__nss_initgroups_database;
 static bool use_initgroups_entry;
 
 
diff --git a/nss/XXX-lookup.c b/nss/XXX-lookup.c
index 49417691b2..839c96e194 100644
--- a/nss/XXX-lookup.c
+++ b/nss/XXX-lookup.c
@@ -52,8 +52,6 @@
 #define DEFAULT_CONFIG NULL
 #endif
 
-service_user *DATABASE_NAME_SYMBOL attribute_hidden;
-
 int
 DB_LOOKUP_FCT (service_user **ni, const char *fct_name, const char *fct2_name,
 	       void **fctp)
diff --git a/nss/getXXent.c b/nss/getXXent.c
index aad374197f..31bd24b924 100644
--- a/nss/getXXent.c
+++ b/nss/getXXent.c
@@ -56,7 +56,7 @@
 /* Prototype of the reentrant version.  */
 extern int INTERNAL (REENTRANT_GETNAME) (LOOKUP_TYPE *resbuf, char *buffer,
 					 size_t buflen, LOOKUP_TYPE **result
-					 H_ERRNO_PARM);
+					 H_ERRNO_PARM) attribute_hidden;
 
 /* We need to protect the dynamic buffer handling.  */
 __libc_lock_define_initialized (static, lock);
diff --git a/nss/nsswitch.c b/nss/nsswitch.c
index 8f31658523..834bef6f9c 100644
--- a/nss/nsswitch.c
+++ b/nss/nsswitch.c
@@ -73,8 +73,10 @@ static const struct
 };
 #define ndatabases (sizeof (databases) / sizeof (databases[0]))
 
+#ifdef USE_NSCD
 /* Flags whether custom rules for database is set.  */
 bool __nss_database_custom[NSS_DBSIDX_max];
+#endif
 
 
 __libc_lock_define_initialized (static, lock)
@@ -304,7 +306,9 @@ __nss_configure_lookup (const char *dbname, const char *service_line)
 
   /* Install new rules.  */
   *databases[cnt].dbp = new_db;
+#ifdef USE_NSCD
   __nss_database_custom[cnt] = true;
+#endif
 
   __libc_lock_unlock (lock);
 
diff --git a/nss/nsswitch.h b/nss/nsswitch.h
index 2b86d63ddb..ab0a512d40 100644
--- a/nss/nsswitch.h
+++ b/nss/nsswitch.h
@@ -96,17 +96,19 @@ typedef struct name_database
 } name_database;
 
 
+#ifdef USE_NSCD
 /* Indices into DATABASES in nsswitch.c and __NSS_DATABASE_CUSTOM.  */
 enum
   {
-#define DEFINE_DATABASE(arg) NSS_DBSIDX_##arg,
-#include "databases.def"
-#undef DEFINE_DATABASE
+# define DEFINE_DATABASE(arg) NSS_DBSIDX_##arg,
+# include "databases.def"
+# undef DEFINE_DATABASE
     NSS_DBSIDX_max
   };
 
 /* Flags whether custom rules for database is set.  */
-extern bool __nss_database_custom[NSS_DBSIDX_max];
+extern bool __nss_database_custom[NSS_DBSIDX_max] attribute_hidden;
+#endif
 
 /* Warning for NSS functions, which don't require dlopen if glibc
    was built with --enable-static-nss.  */
@@ -180,11 +182,13 @@ extern void __nss_setent (const char *func_name,
 			  db_lookup_function lookup_fct,
 			  service_user **nip, service_user **startp,
 			  service_user **last_nip, int stayon,
-			  int *stayon_tmp, int res);
+			  int *stayon_tmp, int res)
+     attribute_hidden;
 extern void __nss_endent (const char *func_name,
 			  db_lookup_function lookup_fct,
 			  service_user **nip, service_user **startp,
-			  service_user **last_nip, int res);
+			  service_user **last_nip, int res)
+     attribute_hidden;
 extern int __nss_getent_r (const char *getent_func_name,
 			   const char *setent_func_name,
 			   db_lookup_function lookup_fct,
@@ -192,10 +196,12 @@ extern int __nss_getent_r (const char *getent_func_name,
 			   service_user **last_nip, int *stayon_tmp,
 			   int res,
 			   void *resbuf, char *buffer, size_t buflen,
-			   void **result, int *h_errnop);
+			   void **result, int *h_errnop)
+     attribute_hidden;
 extern void *__nss_getent (getent_r_function func,
 			   void **resbuf, char **buffer, size_t buflen,
-			   size_t *buffer_size, int *h_errnop);
+			   size_t *buffer_size, int *h_errnop)
+     attribute_hidden;
 struct resolv_context;
 struct hostent;
 extern int __nss_hostname_digits_dots_context (struct resolv_context *,
@@ -221,6 +227,7 @@ libc_hidden_proto (__nss_hostname_digits_dots)
 
 /* Prototypes for __nss_*_lookup2 functions.  */
 #define DEFINE_DATABASE(arg)				    \
+  service_user *__nss_##arg##_database attribute_hidden;    \
   int __nss_##arg##_lookup2 (service_user **, const char *, \
 			     const char *, void **);	    \
   libc_hidden_proto (__nss_##arg##_lookup2)
-- 
2.13.5
