File 0001-Revert-elf-Clean-up-GLIBC_PRIVATE-exports-... of Package glibc

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File 0001-Revert-elf-Clean-up-GLIBC_PRIVATE-exports-of-interna.patch of Package glibc (Revision 54a42f269ab94c8b3aa1d72b0fa020c6)

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From fb4c596e933c801c771accc81a2e6548e29ff1c8 Mon Sep 17 00:00:00 2001
From: Thomas Crider <tcrider@localhost.localdomain>
Date: Wed, 16 Nov 2022 12:35:12 -0700
Subject: [PATCH 1/6] Revert 'elf: Clean up GLIBC_PRIVATE exports of internal
 libdl symbols'

---
 dlfcn/dlerror.c              |   1 +
 elf/Makefile                 |  13 +++-
 elf/Versions                 |   3 +
 elf/dl-addr.c                |   1 +
 elf/dl-libc.c                |   4 ++
 elf/dl-sym.c                 |   2 +
 elf/tst-libc_dlvsym-dso.c    |  25 +++++++
 elf/tst-libc_dlvsym-static.c |  32 +++++++++
 elf/tst-libc_dlvsym.c        |  34 +++++++++
 elf/tst-libc_dlvsym.h        | 130 +++++++++++++++++++++++++++++++++++
 include/dlfcn.h              |  30 ++++----
 11 files changed, 260 insertions(+), 15 deletions(-)
 create mode 100644 elf/tst-libc_dlvsym-dso.c
 create mode 100644 elf/tst-libc_dlvsym-static.c
 create mode 100644 elf/tst-libc_dlvsym.c
 create mode 100644 elf/tst-libc_dlvsym.h

diff --git a/dlfcn/dlerror.c b/dlfcn/dlerror.c
index b899d252..5202ff43 100644
--- a/dlfcn/dlerror.c
+++ b/dlfcn/dlerror.c
@@ -196,3 +196,4 @@ _dlerror_run (void (*operate) (void *), void *args)
       return 1;
     }
 }
+libc_hidden_def (_dlerror_run)
diff --git a/elf/Makefile b/elf/Makefile
index fd77d0c7..d75b85d4 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -289,6 +289,7 @@ tests-static-internal := \
   tst-stackguard1-static \
   tst-tls1-static \
   tst-tls1-static-non-pie \
+  tst-libc_dlvsym-static
   # tests-static-internal
 
 CRT-tst-tls1-static-non-pie := $(csu-objpfx)crt1.o
@@ -499,6 +500,7 @@ tests-internal += \
   tst-dlmopen2 \
   tst-ptrguard1 \
   tst-stackguard1 \
+  tst-libc_dlvsym \
   tst-tls-surplus \
   tst-tls3 \
   tst-tls6 \
@@ -859,6 +861,7 @@ modules-names += \
   tst-latepthreadmod \
   tst-ldconfig-ld-mod \
   tst-main1mod \
+  tst-libc_dlvsym-dso \
   tst-nodelete2mod \
   tst-nodelete-dlclose-dso \
   tst-nodelete-dlclose-plugin \
@@ -978,7 +981,7 @@ modules-names += \
 
 # Most modules build with _ISOMAC defined, but those filtered out
 # depend on internal headers.
-modules-names-tests = $(filter-out ifuncmod% tst-tlsmod%,\
+modules-names-tests = $(filter-out ifuncmod% tst-libc_dlvsym-dso tst-tlsmod%,\
 				   $(modules-names))
 
 # For +depfiles in Makerules.
@@ -2474,6 +2477,14 @@ LDLIBS-tst-absolute-zero-lib.so = tst-absolute-zero-lib.lds
 $(objpfx)tst-absolute-zero-lib.so: $(LDLIBS-tst-absolute-zero-lib.so)
 $(objpfx)tst-absolute-zero: $(objpfx)tst-absolute-zero-lib.so
 
+# Both the main program and the DSO for tst-libc_dlvsym need to link
+# against libdl.
+$(objpfx)tst-libc_dlvsym-dso.so: $(libsupport)
+$(objpfx)tst-libc_dlvsym.out: $(objpfx)tst-libc_dlvsym-dso.so
+tst-libc_dlvsym-static-ENV = \
+  LD_LIBRARY_PATH=$(ld-library-path):$(common-objpfx)dlfcn
+$(objpfx)tst-libc_dlvsym-static.out: $(objpfx)tst-libc_dlvsym-dso.so
+
 $(objpfx)tst-big-note: $(objpfx)tst-big-note-lib.so
 # Avoid creating an ABI tag note, which may come before the
 # artificial, large note in tst-big-note-lib.o and invalidate the
diff --git a/elf/Versions b/elf/Versions
index a9ff278d..a5f4df81 100644
--- a/elf/Versions
+++ b/elf/Versions
@@ -30,6 +30,9 @@ libc {
   }
   GLIBC_PRIVATE {
     # functions used in other libraries
+    _dl_addr;
+    _dl_sym; _dl_vsym;
+    __libc_dlclose; __libc_dlopen_mode; __libc_dlsym; __libc_dlvsym;
     __libc_early_init;
 
     # Internal error handling support.  Interposes the functions in ld.so.
diff --git a/elf/dl-addr.c b/elf/dl-addr.c
index c4278075..e2dd1bc0 100644
--- a/elf/dl-addr.c
+++ b/elf/dl-addr.c
@@ -136,3 +136,4 @@ _dl_addr (const void *address, Dl_info *info,
 
   return result;
 }
+libc_hidden_def (_dl_addr)
diff --git a/elf/dl-libc.c b/elf/dl-libc.c
index 266e068d..a6b9c479 100644
--- a/elf/dl-libc.c
+++ b/elf/dl-libc.c
@@ -161,6 +161,7 @@ __libc_dlopen_mode (const char *name, int mode)
 #endif
   return dlerror_run (do_dlopen, &args) ? NULL : (void *) args.map;
 }
+libc_hidden_def (__libc_dlopen_mode)
 
 #ifndef SHARED
 void *
@@ -190,6 +191,7 @@ __libc_dlsym (void *map, const char *name)
   return (dlerror_run (do_dlsym, &args) ? NULL
 	  : (void *) (DL_SYMBOL_ADDRESS (args.loadbase, args.ref)));
 }
+libc_hidden_def (__libc_dlsym)
 
 /* Replacement for dlvsym.  MAP must be a real map.  This function
    returns NULL without setting the dlerror value in case of static
@@ -216,6 +218,7 @@ __libc_dlvsym (void *map, const char *name, const char *version)
 	  : (void *) (DL_SYMBOL_ADDRESS (args.dlsym.loadbase,
 					 args.dlsym.ref)));
 }
+libc_hidden_def (__libc_dlvsym)
 
 int
 __libc_dlclose (void *map)
@@ -226,6 +229,7 @@ __libc_dlclose (void *map)
 #endif
   return dlerror_run (do_dlclose, map);
 }
+libc_hidden_def (__libc_dlclose)
 
 
 static bool __libc_freeres_fn_section
diff --git a/elf/dl-sym.c b/elf/dl-sym.c
index b1cf42f3..b4631cfd 100644
--- a/elf/dl-sym.c
+++ b/elf/dl-sym.c
@@ -188,9 +188,11 @@ _dl_vsym (void *handle, const char *name, const char *version, void *who)
 
   return do_sym (handle, name, who, &vers, 0);
 }
+libc_hidden_def (_dl_vsym)
 
 void *
 _dl_sym (void *handle, const char *name, void *who)
 {
   return do_sym (handle, name, who, NULL, DL_LOOKUP_RETURN_NEWEST);
 }
+libc_hidden_def (_dl_sym)
diff --git a/elf/tst-libc_dlvsym-dso.c b/elf/tst-libc_dlvsym-dso.c
new file mode 100644
index 00000000..19091ddb
--- /dev/null
+++ b/elf/tst-libc_dlvsym-dso.c
@@ -0,0 +1,25 @@
+/* Compare dlvsym and __libc_dlvsym results.  Shared object code.
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include "tst-libc_dlvsym.h"
+
+void
+compare_vsyms_global (void)
+{
+  compare_vsyms ();
+}
diff --git a/elf/tst-libc_dlvsym-static.c b/elf/tst-libc_dlvsym-static.c
new file mode 100644
index 00000000..19c438c3
--- /dev/null
+++ b/elf/tst-libc_dlvsym-static.c
@@ -0,0 +1,32 @@
+/* Compare dlvsym and __libc_dlvsym results.  Static version.
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <support/xdlfcn.h>
+
+static int
+do_test (void)
+{
+  void *handle = xdlopen ("tst-libc_dlvsym-dso.so", RTLD_LAZY);
+  void (*compare) (void) = xdlsym (handle, "compare_vsyms_global");
+  compare ();
+  xdlclose (handle);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/elf/tst-libc_dlvsym.c b/elf/tst-libc_dlvsym.c
new file mode 100644
index 00000000..823643fb
--- /dev/null
+++ b/elf/tst-libc_dlvsym.c
@@ -0,0 +1,34 @@
+/* Compare dlvsym and __libc_dlvsym results.  Dynamic version.
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include "tst-libc_dlvsym.h"
+
+static int
+do_test (void)
+{
+  compare_vsyms ();
+
+  void *handle = xdlopen ("tst-libc_dlvsym-dso.so", RTLD_LAZY);
+  void (*compare) (void) = xdlsym (handle, "compare_vsyms_global");
+  compare ();
+  xdlclose (handle);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/elf/tst-libc_dlvsym.h b/elf/tst-libc_dlvsym.h
new file mode 100644
index 00000000..1a8f2e92
--- /dev/null
+++ b/elf/tst-libc_dlvsym.h
@@ -0,0 +1,130 @@
+/* Compare dlvsym and __libc_dlvsym results.  Common code.
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* compare_vsyms is the main entry point for these tests.
+
+   Indirectly, It calls __libc_dlvsym (from libc.so; internal
+   interface) and dlvsym (from libdl.so; public interface) to compare
+   the results for a selected set of symbols in libc.so which
+   typically have more than one symbol version.  The two functions are
+   implemented by somewhat different code, and this test checks that
+   their results are the same.
+
+   The versions are generated to range from GLIBC_2.0 to GLIBC_2.Y,
+   with Y being the current __GLIBC_MINOR__ version plus two.  In
+   addition, there is a list of special symbol versions of the form
+   GLIBC_2.Y.Z, which were used for some releases.
+
+   Comparing the two dlvsym results at versions which do not actually
+   exist does not test much, but it will not contribute to false test
+   failures, either.  */
+
+#include <array_length.h>
+#include <gnu/lib-names.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <support/check.h>
+#include <support/xdlfcn.h>
+
+/* Run consistency check for versioned symbol NAME@VERSION.  NB: We
+   may execute in a shared object, so exit on error for proper error
+   reporting.  */
+static void
+compare_vsyms_0 (void *libc_handle, const char *name, const char *version,
+                 bool *pfound)
+{
+  void *dlvsym_address = dlvsym (libc_handle, name, version);
+  void *libc_dlvsym_address
+    = __libc_dlvsym (libc_handle, name, version);
+  if (dlvsym_address != libc_dlvsym_address)
+    FAIL_EXIT1 ("%s@%s mismatch: %p != %p",
+                name, version, dlvsym_address, libc_dlvsym_address);
+  if (dlvsym_address != NULL)
+    *pfound = true;
+}
+
+
+/* Run consistency check for versioned symbol NAME at multiple symbol
+   version.  */
+static void
+compare_vsyms_1 (void *libc_handle, const char *name)
+{
+  bool found = false;
+
+  /* Historic versions which do not follow the usual GLIBC_2.Y
+     pattern, to increase test coverage.  Not all architectures have
+     those, but probing additional versions does not hurt.  */
+  static const char special_versions[][12] =
+    {
+      "GLIBC_2.1.1",
+      "GLIBC_2.1.2",
+      "GLIBC_2.1.3",
+      "GLIBC_2.1.4",
+      "GLIBC_2.2.1",
+      "GLIBC_2.2.2",
+      "GLIBC_2.2.3",
+      "GLIBC_2.2.4",
+      "GLIBC_2.2.5",
+      "GLIBC_2.2.6",
+      "GLIBC_2.3.2",
+      "GLIBC_2.3.3",
+      "GLIBC_2.3.4",
+    };
+  for (int i = 0; i < array_length (special_versions); ++i)
+    compare_vsyms_0 (libc_handle, name, special_versions[i], &found);
+
+  /* Iterate to an out-of-range version, to cover some unused symbols
+     as well.  */
+  for (int minor_version = 0; minor_version <= __GLIBC_MINOR__ + 2;
+       ++minor_version)
+    {
+      char version[30];
+      snprintf (version, sizeof (version), "GLIBC_%d.%d",
+                __GLIBC__, minor_version);
+      compare_vsyms_0 (libc_handle, name, version, &found);
+    }
+
+  if (!found)
+    FAIL_EXIT1 ("symbol %s not found at any version", name);
+}
+
+/* Run consistency checks for various symbols which usually have
+   multiple versions.  */
+static void
+compare_vsyms (void)
+{
+  /* The minor version loop in compare_vsyms_1 needs updating in case
+     we ever switch to glibc 3.0.  */
+  if (__GLIBC__ != 2)
+    FAIL_EXIT1 ("unexpected glibc major version: %d", __GLIBC__);
+
+  /* __libc_dlvsym does not recognize the special RTLD_* handles, so
+     obtain an explicit handle for libc.so.  */
+  void *libc_handle = xdlopen (LIBC_SO, RTLD_LAZY | RTLD_NOLOAD);
+
+
+  /* sys_errlist and sys_siglist were deprecated in glibc 2.32 and they are
+     not available on architectures with base ABI newer than 2.32.  */
+#if TEST_COMPAT (libc, GLIBC_2_0, GLIBC_2_32)
+  compare_vsyms_1 (libc_handle, "_sys_errlist");
+  compare_vsyms_1 (libc_handle, "_sys_siglist");
+#endif
+  compare_vsyms_1 (libc_handle, "quick_exit");
+
+  xdlclose (libc_handle);
+}
diff --git a/include/dlfcn.h b/include/dlfcn.h
index ae25f053..e2dc6cf9 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -49,20 +49,20 @@ extern char **__libc_argv attribute_hidden;
    better error handling semantics for the library.  */
 #define __libc_dlopen(name) \
   __libc_dlopen_mode (name, RTLD_NOW | __RTLD_DLOPEN)
-extern void *__libc_dlopen_mode  (const char *__name, int __mode)
-  attribute_hidden;
-extern void *__libc_dlsym   (void *__map, const char *__name)
-  attribute_hidden;
-extern void *__libc_dlvsym (void *map, const char *name, const char *version)
-  attribute_hidden;
-extern int   __libc_dlclose (void *__map)
-  attribute_hidden;
+extern void *__libc_dlopen_mode  (const char *__name, int __mode);
+extern void *__libc_dlsym   (void *__map, const char *__name);
+extern void *__libc_dlvsym (void *map, const char *name, const char *version);
+extern int   __libc_dlclose (void *__map);
+libc_hidden_proto (__libc_dlopen_mode)
+libc_hidden_proto (__libc_dlsym)
+libc_hidden_proto (__libc_dlvsym)
+libc_hidden_proto (__libc_dlclose)
 
 /* Locate shared object containing the given address.  */
 #ifdef ElfW
 extern int _dl_addr (const void *address, Dl_info *info,
-		     struct link_map **mapp, const ElfW(Sym) **symbolp)
-  attribute_hidden;
+		     struct link_map **mapp, const ElfW(Sym) **symbolp);
+libc_hidden_proto (_dl_addr)
 #endif
 
 struct link_map;
@@ -77,21 +77,23 @@ extern void _dl_close_worker (struct link_map *map, bool force)
 /* Look up NAME in shared object HANDLE (which may be RTLD_DEFAULT or
    RTLD_NEXT).  WHO is the calling function, for RTLD_NEXT.  Returns
    the symbol value, which may be NULL.  */
-extern void *_dl_sym (void *handle, const char *name, void *who)
-  attribute_hidden;
+extern void *_dl_sym (void *handle, const char *name, void *who);
+libc_hidden_proto (_dl_sym)
 
 /* Look up version VERSION of symbol NAME in shared object HANDLE
    (which may be RTLD_DEFAULT or RTLD_NEXT).  WHO is the calling
    function, for RTLD_NEXT.  Returns the symbol value, which may be
    NULL.  */
 extern void *_dl_vsym (void *handle, const char *name, const char *version,
-		       void *who) attribute_hidden;
+		       void *who);
+libc_hidden_proto (_dl_vsym)
 
 /* Helper function for <dlfcn.h> functions.  Runs the OPERATE function via
    _dl_catch_error.  Returns zero for success, nonzero for failure; and
    arranges for `dlerror' to return the error details.
    ARGS is passed as argument to OPERATE.  */
-extern int _dlerror_run (void (*operate) (void *), void *args) attribute_hidden;
+extern int _dlerror_run (void (*operate) (void *), void *args);
+libc_hidden_proto (_dlerror_run)
 
 /* This structure is used to make the outer (statically linked)
    implementation of dlopen and related functions to the inner libc
-- 
2.38.1

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