glibc/glibc-RHEL-46979-2.patch

From ee1ada1bdb8074de6e1bdc956ab19aef7b6a7872 Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Thu, 3 Nov 2022 09:39:31 +0100
Subject: elf: Rework exception handling in the dynamic loader [BZ #25486]

The old exception handling implementation used function interposition
to replace the dynamic loader implementation (no TLS support) with the
libc implementation (TLS support).  This results in problems if the
link order between the dynamic loader and libc is reversed (bug 25486).

The new implementation moves the entire implementation of the
exception handling functions back into the dynamic loader, using
THREAD_GETMEM and THREAD_SETMEM for thread-local data support.
These depends on Hurd support for these macros, added in commit
b65a82e4e757c1e6cb7073916 ("hurd: Add THREAD_GET/SETMEM/_NC").

One small obstacle is that the exception handling facilities are used
before the TCB has been set up, so a check is needed if the TCB is
available.  If not, a regular global variable is used to store the
exception handling information.

Also rename dl-error.c to dl-catch.c, to avoid confusion with the
dlerror function.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

Conflicts
	Rebased due to context changes

diff -rupN a/elf/Makefile b/elf/Makefile
--- a/elf/Makefile	2024-08-29 11:28:38.488322915 -0400
+++ b/elf/Makefile	2024-08-29 11:29:16.773809945 -0400
@@ -34,7 +34,6 @@ routines = \
   dl-addr \
   dl-addr-obj \
   dl-early_allocate \
-  dl-error \
   dl-iteratephdr \
   dl-libc \
   dl-origin \
@@ -52,6 +51,7 @@ routines = \
 # profiled libraries.
 dl-routines = \
   dl-call-libc-early-init \
+  dl-catch \
   dl-close \
   dl-debug \
   dl-deps \
@@ -127,7 +127,6 @@ rtld-routines = \
   dl-diagnostics-cpu \
   dl-diagnostics-kernel \
   dl-environ \
-  dl-error-minimal \
   dl-hwcaps \
   dl-hwcaps-subdirs \
   dl-hwcaps_split \
diff -rupN a/elf/Versions b/elf/Versions
--- a/elf/Versions	2024-08-29 11:28:36.214234588 -0400
+++ b/elf/Versions	2024-08-29 11:29:16.778810139 -0400
@@ -23,10 +23,6 @@ libc {
   GLIBC_PRIVATE {
     # functions used in other libraries
     __libc_early_init;
-
-    # Internal error handling support.  Interposes the functions in ld.so.
-    _dl_signal_exception; _dl_catch_exception;
-    _dl_signal_error; _dl_catch_error;
   }
 }
 
@@ -69,10 +65,8 @@ ld {
 
     # Internal error handling support.
     _dl_exception_create; _dl_exception_create_format; _dl_exception_free;
-
-    # Internal error handling support.  Interposed by libc.so.
     _dl_signal_exception; _dl_catch_exception;
-    _dl_signal_error; _dl_catch_error;
+    _dl_signal_error;
 
     # Set value of a tunable.
     __tunable_get_val;
diff -rupN a/elf/dl-catch.c b/elf/dl-catch.c
--- a/elf/dl-catch.c	1969-12-31 19:00:00.000000000 -0500
+++ b/elf/dl-catch.c	2024-08-29 11:29:16.782810295 -0400
@@ -0,0 +1,261 @@
+/* Exception handling in the dynamic linker.
+   Copyright (C) 1995-2022 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 <libintl.h>
+#include <setjmp.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <ldsodefs.h>
+#include <stdio.h>
+#include <tls.h>
+
+/* This structure communicates state between _dl_catch_error and
+   _dl_signal_error.  */
+struct rtld_catch
+  {
+    struct dl_exception *exception; /* The exception data is stored there.  */
+    volatile int *errcode;	/* Return value of _dl_signal_error.  */
+    jmp_buf env;		/* longjmp here on error.  */
+  };
+
+/* Multiple threads at once can use the `_dl_catch_error' function.
+   The calls can come from `_dl_map_object_deps', `_dlerror_run', or
+   from any of the libc functionality which loads dynamic objects
+   (NSS, iconv).  Therefore we have to be prepared to save the state
+   in thread-local memory.  We use THREAD_GETMEM and THREAD_SETMEM
+   instead of ELF TLS because ELF TLS is not available in the dynamic
+   loader.  Additionally, the exception handling mechanism must be
+   usable before the TCB has been set up, which is why
+   rtld_catch_notls is used if !__rtld_tls_init_tp_called.  This is
+   not needed for static builds, where initialization completes before
+   static dlopen etc. can be called.  */
+
+#if IS_IN (rtld)
+static struct rtld_catch *rtld_catch_notls;
+#endif
+
+static struct rtld_catch *
+get_catch (void)
+{
+#if IS_IN (rtld)
+  if (!__rtld_tls_init_tp_called)
+    return rtld_catch_notls;
+  else
+#endif
+    return THREAD_GETMEM (THREAD_SELF, rtld_catch);
+}
+
+static void
+set_catch (struct rtld_catch *catch)
+{
+#if IS_IN (rtld)
+  if (!__rtld_tls_init_tp_called)
+    rtld_catch_notls = catch;
+  else
+#endif
+    THREAD_SETMEM (THREAD_SELF, rtld_catch, catch);
+}
+
+/* Lossage while resolving the program's own symbols is always fatal.  */
+static void
+__attribute__ ((noreturn))
+fatal_error (int errcode, const char *objname, const char *occasion,
+	     const char *errstring)
+{
+  char buffer[1024];
+  _dl_fatal_printf ("%s: %s: %s%s%s%s%s\n",
+		    RTLD_PROGNAME,
+		    occasion ?: N_("error while loading shared libraries"),
+		    objname, *objname ? ": " : "",
+		    errstring, errcode ? ": " : "",
+		    (errcode
+		     ? __strerror_r (errcode, buffer, sizeof buffer)
+		     : ""));
+}
+
+void
+_dl_signal_exception (int errcode, struct dl_exception *exception,
+		      const char *occasion)
+{
+  struct rtld_catch *lcatch = get_catch ();
+  if (lcatch != NULL)
+    {
+      *lcatch->exception = *exception;
+      *lcatch->errcode = errcode;
+
+      /* We do not restore the signal mask because none was saved.  */
+      __longjmp (lcatch->env[0].__jmpbuf, 1);
+    }
+  else
+    fatal_error (errcode, exception->objname, occasion, exception->errstring);
+}
+rtld_hidden_def (_dl_signal_exception)
+
+void
+_dl_signal_error (int errcode, const char *objname, const char *occation,
+		  const char *errstring)
+{
+  struct rtld_catch *lcatch = get_catch ();
+
+  if (! errstring)
+    errstring = N_("DYNAMIC LINKER BUG!!!");
+
+  if (lcatch != NULL)
+    {
+      _dl_exception_create (lcatch->exception, objname, errstring);
+      *lcatch->errcode = errcode;
+
+      /* We do not restore the signal mask because none was saved.  */
+      __longjmp (lcatch->env[0].__jmpbuf, 1);
+    }
+  else
+    fatal_error (errcode, objname, occation, errstring);
+}
+rtld_hidden_def (_dl_signal_error)
+
+#if IS_IN (rtld)
+/* This points to a function which is called when a continuable error is
+   received.  Unlike the handling of `catch' this function may return.
+   The arguments will be the `errstring' and `objname'.
+
+   Since this functionality is not used in normal programs (only in ld.so)
+   we do not care about multi-threaded programs here.  We keep this as a
+   global variable.  */
+static receiver_fct receiver;
+
+void
+_dl_signal_cexception (int errcode, struct dl_exception *exception,
+		       const char *occasion)
+{
+  if (__builtin_expect (GLRO(dl_debug_mask)
+			& ~(DL_DEBUG_STATISTICS), 0))
+    _dl_debug_printf ("%s: error: %s: %s (%s)\n",
+		      exception->objname, occasion,
+		      exception->errstring, receiver ? "continued" : "fatal");
+
+  if (receiver)
+    {
+      /* We are inside _dl_receive_error.  Call the user supplied
+	 handler and resume the work.  The receiver will still be
+	 installed.  */
+      (*receiver) (errcode, exception->objname, exception->errstring);
+    }
+  else
+    _dl_signal_exception (errcode, exception, occasion);
+}
+
+void
+_dl_signal_cerror (int errcode, const char *objname, const char *occation,
+		   const char *errstring)
+{
+  if (__builtin_expect (GLRO(dl_debug_mask)
+			& ~(DL_DEBUG_STATISTICS), 0))
+    _dl_debug_printf ("%s: error: %s: %s (%s)\n", objname, occation,
+		      errstring, receiver ? "continued" : "fatal");
+
+  if (receiver)
+    {
+      /* We are inside _dl_receive_error.  Call the user supplied
+	 handler and resume the work.  The receiver will still be
+	 installed.  */
+      (*receiver) (errcode, objname, errstring);
+    }
+  else
+    _dl_signal_error (errcode, objname, occation, errstring);
+}
+
+void
+_dl_receive_error (receiver_fct fct, void (*operate) (void *), void *args)
+{
+  struct rtld_catch *old_catch = get_catch ();
+  receiver_fct old_receiver = receiver;
+
+  /* Set the new values.  */
+  set_catch (NULL);
+  receiver = fct;
+
+  (*operate) (args);
+
+  set_catch (old_catch);
+  receiver = old_receiver;
+}
+#endif
+
+int
+_dl_catch_exception (struct dl_exception *exception,
+		     void (*operate) (void *), void *args)
+{
+  /* If exception is NULL, temporarily disable exception handling.
+     Exceptions during operate (args) are fatal.  */
+  if (exception == NULL)
+    {
+      struct rtld_catch *old_catch = get_catch ();
+      set_catch (NULL);
+      operate (args);
+      /* If we get here, the operation was successful.  */
+      set_catch (old_catch);
+      return 0;
+    }
+
+  /* We need not handle `receiver' since setting a `catch' is handled
+     before it.  */
+
+  /* Only this needs to be marked volatile, because it is the only local
+     variable that gets changed between the setjmp invocation and the
+     longjmp call.  All others are just set here (before setjmp) and read
+     in _dl_signal_error (before longjmp).  */
+  volatile int errcode;
+
+  struct rtld_catch c;
+  /* Don't use an initializer since we don't need to clear C.env.  */
+  c.exception = exception;
+  c.errcode = &errcode;
+
+  struct rtld_catch *old = get_catch ();
+  set_catch (&c);
+
+  /* Do not save the signal mask.  */
+  if (__builtin_expect (__sigsetjmp (c.env, 0), 0) == 0)
+    {
+      (*operate) (args);
+      set_catch (old);
+      *exception = (struct dl_exception) { NULL };
+      return 0;
+    }
+
+  /* We get here only if we longjmp'd out of OPERATE.
+     _dl_signal_exception has already stored values into
+     *EXCEPTION.  */
+  set_catch (old);
+  return errcode;
+}
+rtld_hidden_def (_dl_catch_exception)
+
+int
+_dl_catch_error (const char **objname, const char **errstring,
+		 bool *mallocedp, void (*operate) (void *), void *args)
+{
+  struct dl_exception exception;
+  int errorcode = _dl_catch_exception (&exception, operate, args);
+  *objname = exception.objname;
+  *errstring = exception.errstring;
+  *mallocedp = exception.message_buffer == exception.errstring;
+  return errorcode;
+}
diff -rupN a/elf/dl-error-minimal.c b/elf/dl-error-minimal.c
--- a/elf/dl-error-minimal.c	2021-08-01 21:33:43.000000000 -0400
+++ b/elf/dl-error-minimal.c	1969-12-31 19:00:00.000000000 -0500
@@ -1,23 +0,0 @@
-/* Error handling for runtime dynamic linker, minimal version.
-   Copyright (C) 1995-2021 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/>.  */
-
-/* This version does lives in ld.so, does not use thread-local data
-   and supports _dl_signal_cerror and _dl_receive_error.  */
-
-#define DL_ERROR_BOOTSTRAP 1
-#include "dl-error-skeleton.c"
diff -rupN a/elf/dl-error-skeleton.c b/elf/dl-error-skeleton.c
--- a/elf/dl-error-skeleton.c	2021-08-01 21:33:43.000000000 -0400
+++ b/elf/dl-error-skeleton.c	1969-12-31 19:00:00.000000000 -0500
@@ -1,263 +0,0 @@
-/* Template for error handling for runtime dynamic linker.
-   Copyright (C) 1995-2021 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/>.  */
-
-/* The following macro needs to be defined before including this
-   skeleton file:
-
-   DL_ERROR_BOOTSTRAP
-
-     If 1, do not use TLS and implement _dl_signal_cerror and
-     _dl_receive_error.  If 0, TLS is used, and the variants with
-     error callbacks are not provided.  */
-
-
-#include <libintl.h>
-#include <setjmp.h>
-#include <stdbool.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <ldsodefs.h>
-#include <stdio.h>
-
-/* This structure communicates state between _dl_catch_error and
-   _dl_signal_error.  */
-struct catch
-  {
-    struct dl_exception *exception; /* The exception data is stored there.  */
-    volatile int *errcode;	/* Return value of _dl_signal_error.  */
-    jmp_buf env;		/* longjmp here on error.  */
-  };
-
-/* Multiple threads at once can use the `_dl_catch_error' function.  The
-   calls can come from `_dl_map_object_deps', `_dlerror_run', or from
-   any of the libc functionality which loads dynamic objects (NSS, iconv).
-   Therefore we have to be prepared to save the state in thread-local
-   memory.  */
-#if !DL_ERROR_BOOTSTRAP
-static __thread struct catch *catch_hook attribute_tls_model_ie;
-#else
-/* The version of this code in ld.so cannot use thread-local variables
-   and is used during bootstrap only.  */
-static struct catch *catch_hook;
-#endif
-
-#if DL_ERROR_BOOTSTRAP
-/* This points to a function which is called when an continuable error is
-   received.  Unlike the handling of `catch' this function may return.
-   The arguments will be the `errstring' and `objname'.
-
-   Since this functionality is not used in normal programs (only in ld.so)
-   we do not care about multi-threaded programs here.  We keep this as a
-   global variable.  */
-static receiver_fct receiver;
-#endif /* DL_ERROR_BOOTSTRAP */
-
-/* Lossage while resolving the program's own symbols is always fatal.  */
-static void
-__attribute__ ((noreturn))
-fatal_error (int errcode, const char *objname, const char *occasion,
-	     const char *errstring)
-{
-  char buffer[1024];
-  _dl_fatal_printf ("%s: %s: %s%s%s%s%s\n",
-		    RTLD_PROGNAME,
-		    occasion ?: N_("error while loading shared libraries"),
-		    objname, *objname ? ": " : "",
-		    errstring, errcode ? ": " : "",
-		    (errcode
-		     ? __strerror_r (errcode, buffer, sizeof buffer)
-		     : ""));
-}
-
-void
-_dl_signal_exception (int errcode, struct dl_exception *exception,
-		      const char *occasion)
-{
-  struct catch *lcatch = catch_hook;
-  if (lcatch != NULL)
-    {
-      *lcatch->exception = *exception;
-      *lcatch->errcode = errcode;
-
-      /* We do not restore the signal mask because none was saved.  */
-      __longjmp (lcatch->env[0].__jmpbuf, 1);
-    }
-  else
-    fatal_error (errcode, exception->objname, occasion, exception->errstring);
-}
-libc_hidden_def (_dl_signal_exception)
-
-void
-_dl_signal_error (int errcode, const char *objname, const char *occation,
-		  const char *errstring)
-{
-  struct catch *lcatch = catch_hook;
-
-  if (! errstring)
-    errstring = N_("DYNAMIC LINKER BUG!!!");
-
-  if (lcatch != NULL)
-    {
-      _dl_exception_create (lcatch->exception, objname, errstring);
-      *lcatch->errcode = errcode;
-
-      /* We do not restore the signal mask because none was saved.  */
-      __longjmp (lcatch->env[0].__jmpbuf, 1);
-    }
-  else
-    fatal_error (errcode, objname, occation, errstring);
-}
-libc_hidden_def (_dl_signal_error)
-
-
-#if DL_ERROR_BOOTSTRAP
-void
-_dl_signal_cexception (int errcode, struct dl_exception *exception,
-		       const char *occasion)
-{
-  if (__builtin_expect (GLRO(dl_debug_mask)
-			& ~(DL_DEBUG_STATISTICS|DL_DEBUG_PRELINK), 0))
-    _dl_debug_printf ("%s: error: %s: %s (%s)\n",
-		      exception->objname, occasion,
-		      exception->errstring, receiver ? "continued" : "fatal");
-
-  if (receiver)
-    {
-      /* We are inside _dl_receive_error.  Call the user supplied
-	 handler and resume the work.  The receiver will still be
-	 installed.  */
-      (*receiver) (errcode, exception->objname, exception->errstring);
-    }
-  else
-    _dl_signal_exception (errcode, exception, occasion);
-}
-
-void
-_dl_signal_cerror (int errcode, const char *objname, const char *occation,
-		   const char *errstring)
-{
-  if (__builtin_expect (GLRO(dl_debug_mask)
-			& ~(DL_DEBUG_STATISTICS|DL_DEBUG_PRELINK), 0))
-    _dl_debug_printf ("%s: error: %s: %s (%s)\n", objname, occation,
-		      errstring, receiver ? "continued" : "fatal");
-
-  if (receiver)
-    {
-      /* We are inside _dl_receive_error.  Call the user supplied
-	 handler and resume the work.  The receiver will still be
-	 installed.  */
-      (*receiver) (errcode, objname, errstring);
-    }
-  else
-    _dl_signal_error (errcode, objname, occation, errstring);
-}
-#endif /* DL_ERROR_BOOTSTRAP */
-
-int
-_dl_catch_exception (struct dl_exception *exception,
-		     void (*operate) (void *), void *args)
-{
-  /* If exception is NULL, temporarily disable exception handling.
-     Exceptions during operate (args) are fatal.  */
-  if (exception == NULL)
-    {
-      struct catch *const old = catch_hook;
-      catch_hook = NULL;
-      operate (args);
-      /* If we get here, the operation was successful.  */
-      catch_hook = old;
-      return 0;
-    }
-
-  /* We need not handle `receiver' since setting a `catch' is handled
-     before it.  */
-
-  /* Only this needs to be marked volatile, because it is the only local
-     variable that gets changed between the setjmp invocation and the
-     longjmp call.  All others are just set here (before setjmp) and read
-     in _dl_signal_error (before longjmp).  */
-  volatile int errcode;
-
-  struct catch c;
-  /* Don't use an initializer since we don't need to clear C.env.  */
-  c.exception = exception;
-  c.errcode = &errcode;
-
-  struct catch *const old = catch_hook;
-  catch_hook = &c;
-
-  /* Do not save the signal mask.  */
-  if (__builtin_expect (__sigsetjmp (c.env, 0), 0) == 0)
-    {
-      (*operate) (args);
-      catch_hook = old;
-      *exception = (struct dl_exception) { NULL };
-      return 0;
-    }
-
-  /* We get here only if we longjmp'd out of OPERATE.
-     _dl_signal_exception has already stored values into
-     *EXCEPTION.  */
-  catch_hook = old;
-  return errcode;
-}
-libc_hidden_def (_dl_catch_exception)
-
-int
-_dl_catch_error (const char **objname, const char **errstring,
-		 bool *mallocedp, void (*operate) (void *), void *args)
-{
-  struct dl_exception exception;
-  int errorcode = _dl_catch_exception (&exception, operate, args);
-  *objname = exception.objname;
-  *errstring = exception.errstring;
-  *mallocedp = exception.message_buffer == exception.errstring;
-  return errorcode;
-}
-libc_hidden_def (_dl_catch_error)
-
-#if DL_ERROR_BOOTSTRAP
-void
-_dl_receive_error (receiver_fct fct, void (*operate) (void *), void *args)
-{
-  struct catch *old_catch = catch_hook;
-  receiver_fct old_receiver = receiver;
-
-  /* Set the new values.  */
-  catch_hook = NULL;
-  receiver = fct;
-
-  (*operate) (args);
-
-  catch_hook = old_catch;
-  receiver = old_receiver;
-}
-
-/* Forwarder used for initializing GLRO (_dl_catch_error).  */
-int
-_rtld_catch_error (const char **objname, const char **errstring,
-		   bool *mallocedp, void (*operate) (void *),
-		   void *args)
-{
-  /* The reference to _dl_catch_error will eventually be relocated to
-     point to the implementation in libc.so.  */
-  return _dl_catch_error (objname, errstring, mallocedp, operate, args);
-}
-
-#endif /* DL_ERROR_BOOTSTRAP */
diff -rupN a/elf/dl-error.c b/elf/dl-error.c
--- a/elf/dl-error.c	2021-08-01 21:33:43.000000000 -0400
+++ b/elf/dl-error.c	1969-12-31 19:00:00.000000000 -0500
@@ -1,27 +0,0 @@
-/* Error handling for runtime dynamic linker, full version.
-   Copyright (C) 1995-2021 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/>.  */
-
-/* This implementation lives in libc.so because it uses thread-local
-   data, which is not available in ld.so.  It interposes the version
-   in dl-error-minimal.c after ld.so bootstrap.
-
-   The signal/catch mechanism is used by the audit framework, which
-   means that even in ld.so, not all errors are fatal.  */
-
-#define DL_ERROR_BOOTSTRAP 0
-#include "dl-error-skeleton.c"
diff -rupN a/elf/rtld.c b/elf/rtld.c
--- a/elf/rtld.c	2024-08-29 11:28:38.569326061 -0400
+++ b/elf/rtld.c	2024-08-29 11:29:16.798810916 -0400
@@ -377,7 +377,7 @@ struct rtld_global_ro _rtld_global_ro at
     ._dl_lookup_symbol_x = _dl_lookup_symbol_x,
     ._dl_open = _dl_open,
     ._dl_close = _dl_close,
-    ._dl_catch_error = _rtld_catch_error,
+    ._dl_catch_error = _dl_catch_error,
     ._dl_error_free = _dl_error_free,
     ._dl_tls_get_addr_soft = _dl_tls_get_addr_soft,
 #ifdef HAVE_DL_DISCOVER_OSVERSION
diff -rupN a/nptl/descr.h b/nptl/descr.h
--- a/nptl/descr.h	2024-08-29 11:28:37.858298444 -0400
+++ b/nptl/descr.h	2024-08-29 11:29:16.801811033 -0400
@@ -396,6 +396,9 @@ struct pthread
      masked.)  */
   sigset_t sigmask;
 
+  /* Used by the exception handling implementation in the dynamic loader.  */
+  struct rtld_catch *rtld_catch;
+
   /* Indicates whether is a C11 thread created by thrd_creat.  */
   bool c11;
 
diff -rupN a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
--- a/sysdeps/generic/ldsodefs.h	2024-08-29 11:28:38.571326139 -0400
+++ b/sysdeps/generic/ldsodefs.h	2024-08-29 11:29:16.805811188 -0400
@@ -897,13 +897,13 @@ rtld_hidden_proto (_dl_exception_free)
 void _dl_signal_exception (int errcode, struct dl_exception *,
 			   const char *occasion)
   __attribute__ ((__noreturn__));
-libc_hidden_proto (_dl_signal_exception)
+rtld_hidden_proto (_dl_signal_exception)
 
 /* Like _dl_signal_exception, but creates the exception first.  */
 extern void _dl_signal_error (int errcode, const char *object,
 			      const char *occasion, const char *errstring)
      __attribute__ ((__noreturn__));
-libc_hidden_proto (_dl_signal_error)
+rtld_hidden_proto (_dl_signal_error)
 
 /* Like _dl_signal_exception, but may return when called in the
    context of _dl_receive_error.  This is only used during ld.so
@@ -955,11 +955,7 @@ extern void _dl_receive_error (receiver_
    the returned string is allocated using the libc's malloc.  */
 extern int _dl_catch_error (const char **objname, const char **errstring,
 			    bool *mallocedp, void (*operate) (void *),
-			    void *args);
-libc_hidden_proto (_dl_catch_error)
-
-/* Used for initializing GLRO (_dl_catch_error).  */
-extern __typeof__ (_dl_catch_error) _rtld_catch_error attribute_hidden;
+			    void *args) attribute_hidden;
 
 /* Call OPERATE (ARGS).  If no error occurs, set *EXCEPTION to zero.
    Otherwise, store a copy of the raised exception in *EXCEPTION,
@@ -968,7 +964,7 @@ extern __typeof__ (_dl_catch_error) _rtl
    disabled (so that exceptions are fatal).  */
 int _dl_catch_exception (struct dl_exception *exception,
 			 void (*operate) (void *), void *args);
-libc_hidden_proto (_dl_catch_exception)
+rtld_hidden_proto (_dl_catch_exception)
 
 /* Open the shared object NAME and map in its segments.
    LOADER's DT_RPATH is used in searching for NAME.
diff -rupN a/sysdeps/generic/localplt.data b/sysdeps/generic/localplt.data
--- a/sysdeps/generic/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/generic/localplt.data	2024-08-29 11:29:16.806811227 -0400
@@ -6,8 +6,3 @@ libc.so: free
 libc.so: malloc
 libc.so: realloc
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/mach/hurd/i386/localplt.data b/sysdeps/mach/hurd/i386/localplt.data
--- a/sysdeps/mach/hurd/i386/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/mach/hurd/i386/localplt.data	2024-08-29 11:29:16.808811305 -0400
@@ -8,11 +8,6 @@ libc.so: free + REL R_386_GLOB_DAT
 libc.so: malloc + REL R_386_GLOB_DAT
 libc.so: realloc + REL R_386_GLOB_DAT
 libm.so: matherr + REL R_386_GLOB_DAT
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error + REL R_386_GLOB_DAT
-ld.so: _dl_catch_error + REL R_386_GLOB_DAT
-ld.so: _dl_signal_exception + REL R_386_GLOB_DAT
-ld.so: _dl_catch_exception + REL R_386_GLOB_DAT
 # The dynamic linker has its own versions of basic functions for initial loading
 # of shared libraries.  These need to be overriden by libc once loaded.
 ld.so: __open ?
diff -rupN a/sysdeps/mach/hurd/i386/tls.h b/sysdeps/mach/hurd/i386/tls.h
--- a/sysdeps/mach/hurd/i386/tls.h	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/mach/hurd/i386/tls.h	2024-08-29 11:29:16.810811382 -0400
@@ -48,6 +48,9 @@ typedef struct
      compatible with the i386 Linux version.  */
   mach_port_t reply_port;      /* This thread's reply port.  */
   struct hurd_sigstate *_hurd_sigstate;
+
+  /* Used by the exception handling implementation in the dynamic loader.  */
+  struct rtld_catch *rtld_catch;
 } tcbhead_t;
 #endif
 
diff -rupN a/sysdeps/unix/sysv/linux/aarch64/localplt.data b/sysdeps/unix/sysv/linux/aarch64/localplt.data
--- a/sysdeps/unix/sysv/linux/aarch64/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/aarch64/localplt.data	2024-08-29 11:29:16.810811382 -0400
@@ -11,8 +11,3 @@ libm.so: matherr
 libc.so: __getauxval ?
 # The dynamic loader needs __tls_get_addr for TLS.
 ld.so: __tls_get_addr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/alpha/localplt.data b/sysdeps/unix/sysv/linux/alpha/localplt.data
--- a/sysdeps/unix/sysv/linux/alpha/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/alpha/localplt.data	2024-08-29 11:29:16.810811382 -0400
@@ -25,8 +25,3 @@ libm.so: matherr + RELA R_ALPHA_GLOB_DAT
 libm.so: __atan2
 # The dynamic loader needs __tls_get_addr for TLS.
 ld.so: __tls_get_addr ?
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error + RELA R_ALPHA_GLOB_DAT
-ld.so: _dl_catch_error + RELA R_ALPHA_GLOB_DAT
-ld.so: _dl_signal_exception + RELA R_ALPHA_GLOB_DAT
-ld.so: _dl_catch_exception + RELA R_ALPHA_GLOB_DAT
diff -rupN a/sysdeps/unix/sysv/linux/arc/localplt.data b/sysdeps/unix/sysv/linux/arc/localplt.data
--- a/sysdeps/unix/sysv/linux/arc/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/arc/localplt.data	2024-08-29 11:29:16.814811538 -0400
@@ -4,8 +4,3 @@ libc.so: calloc
 libc.so: free
 # At -Os, a struct assignment in libgcc-static pulls this in
 libc.so: memcpy ?
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/arm/localplt.data b/sysdeps/unix/sysv/linux/arm/localplt.data
--- a/sysdeps/unix/sysv/linux/arm/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/arm/localplt.data	2024-08-29 11:29:16.814811538 -0400
@@ -6,8 +6,3 @@ libc.so: realloc
 libm.so: matherr
 # The dynamic loader needs __tls_get_addr for TLS.
 ld.so: __tls_get_addr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/csky/localplt.data b/sysdeps/unix/sysv/linux/csky/localplt.data
--- a/sysdeps/unix/sysv/linux/csky/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/csky/localplt.data	2024-08-29 11:29:16.814811538 -0400
@@ -5,8 +5,3 @@ libc.so: calloc
 libc.so: free
 libc.so: malloc
 libc.so: realloc
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/hppa/localplt.data b/sysdeps/unix/sysv/linux/hppa/localplt.data
--- a/sysdeps/unix/sysv/linux/hppa/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/hppa/localplt.data	2024-08-29 11:29:16.814811538 -0400
@@ -9,8 +9,3 @@ libc.so: __sigsetjmp
 libc.so: _IO_funlockfile
 libc.so: __errno_location
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/i386/localplt.data b/sysdeps/unix/sysv/linux/i386/localplt.data
--- a/sysdeps/unix/sysv/linux/i386/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/i386/localplt.data	2024-08-29 11:29:16.816811615 -0400
@@ -6,8 +6,3 @@ libc.so: free + REL R_386_GLOB_DAT
 libc.so: malloc + REL R_386_GLOB_DAT
 libc.so: realloc + REL R_386_GLOB_DAT
 libm.so: matherr + REL R_386_GLOB_DAT
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error + REL R_386_GLOB_DAT
-ld.so: _dl_catch_error + REL R_386_GLOB_DAT
-ld.so: _dl_signal_exception + REL R_386_GLOB_DAT
-ld.so: _dl_catch_exception + REL R_386_GLOB_DAT
diff -rupN a/sysdeps/unix/sysv/linux/ia64/localplt.data b/sysdeps/unix/sysv/linux/ia64/localplt.data
--- a/sysdeps/unix/sysv/linux/ia64/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/ia64/localplt.data	2024-08-29 11:29:16.816811615 -0400
@@ -5,8 +5,3 @@ libc.so: realloc
 libm.so: matherr
 libm.so: matherrf
 libm.so: matherrl
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/m68k/coldfire/localplt.data b/sysdeps/unix/sysv/linux/m68k/coldfire/localplt.data
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/localplt.data	2024-08-29 11:29:16.819811732 -0400
@@ -4,8 +4,3 @@ libc.so: free
 libc.so: malloc
 libc.so: realloc
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/m68k/m680x0/localplt.data b/sysdeps/unix/sysv/linux/m68k/m680x0/localplt.data
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/localplt.data	2024-08-29 11:29:16.820811771 -0400
@@ -5,8 +5,3 @@ libc.so: free
 libc.so: malloc
 libc.so: realloc
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/microblaze/localplt.data b/sysdeps/unix/sysv/linux/microblaze/localplt.data
--- a/sysdeps/unix/sysv/linux/microblaze/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/microblaze/localplt.data	2024-08-29 11:29:16.822811848 -0400
@@ -6,8 +6,3 @@ libc.so: realloc
 libm.so: matherr
 # The dynamic loader needs __tls_get_addr for TLS.
 ld.so: __tls_get_addr ?
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/nios2/localplt.data b/sysdeps/unix/sysv/linux/nios2/localplt.data
--- a/sysdeps/unix/sysv/linux/nios2/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/nios2/localplt.data	2024-08-29 11:29:16.825811965 -0400
@@ -27,8 +27,3 @@ libc.so: __eqdf2
 libc.so: __extendsfdf2
 libc.so: __floatundidf ?
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/localplt.data b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/localplt.data
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/localplt.data	2024-08-29 11:29:16.829812120 -0400
@@ -4,8 +4,3 @@ libc.so: free
 libc.so: malloc
 libc.so: realloc
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/localplt.data b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/localplt.data
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/localplt.data	2024-08-29 11:29:16.831812198 -0400
@@ -35,8 +35,3 @@ libc.so: realloc
 libm.so: copysignl ?
 libm.so: fabsl
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/powerpc/powerpc64/localplt.data b/sysdeps/unix/sysv/linux/powerpc/powerpc64/localplt.data
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/localplt.data	2024-08-29 11:29:16.833812276 -0400
@@ -3,8 +3,3 @@ libc.so: free
 libc.so: malloc
 libc.so: realloc
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/riscv/localplt.data b/sysdeps/unix/sysv/linux/riscv/localplt.data
--- a/sysdeps/unix/sysv/linux/riscv/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/riscv/localplt.data	2024-08-29 11:29:16.835812353 -0400
@@ -6,8 +6,3 @@ libc.so: free
 libc.so: malloc
 libc.so: memset ?
 libc.so: realloc
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/s390/localplt.data b/sysdeps/unix/sysv/linux/s390/localplt.data
--- a/sysdeps/unix/sysv/linux/s390/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/s390/localplt.data	2024-08-29 11:29:16.837812431 -0400
@@ -4,8 +4,3 @@ libc.so: free
 libc.so: malloc
 libc.so: realloc
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/sh/localplt.data b/sysdeps/unix/sysv/linux/sh/localplt.data
--- a/sysdeps/unix/sysv/linux/sh/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/sh/localplt.data	2024-08-29 11:29:16.838812470 -0400
@@ -11,8 +11,3 @@ libc.so: __errno_location
 libm.so: matherr
 # Generated by the compiler because there is no trap insn pattern.
 libc.so: abort ?
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/sparc/sparc32/localplt.data b/sysdeps/unix/sysv/linux/sparc/sparc32/localplt.data
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/localplt.data	2024-08-29 11:29:16.840812547 -0400
@@ -18,8 +18,3 @@ libc.so: free
 libc.so: malloc
 libc.so: realloc
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data b/sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data	2024-08-29 11:29:16.844812703 -0400
@@ -17,8 +17,3 @@ libc.so: free
 libc.so: malloc
 libc.so: realloc
 libm.so: matherr
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error
-ld.so: _dl_catch_error
-ld.so: _dl_signal_exception
-ld.so: _dl_catch_exception
diff -rupN a/sysdeps/x86_64/localplt.data b/sysdeps/x86_64/localplt.data
--- a/sysdeps/x86_64/localplt.data	2021-08-01 21:33:43.000000000 -0400
+++ b/sysdeps/x86_64/localplt.data	2024-08-29 11:29:16.847812819 -0400
@@ -8,8 +8,3 @@ libc.so: free + RELA R_X86_64_GLOB_DAT
 libc.so: malloc + RELA R_X86_64_GLOB_DAT
 libc.so: realloc + RELA R_X86_64_GLOB_DAT
 libm.so: matherr + RELA R_X86_64_GLOB_DAT
-# The TLS-enabled version of these functions is interposed from libc.so.
-ld.so: _dl_signal_error + RELA R_X86_64_GLOB_DAT
-ld.so: _dl_catch_error + RELA R_X86_64_GLOB_DAT
-ld.so: _dl_signal_exception + RELA R_X86_64_GLOB_DAT
-ld.so: _dl_catch_exception + RELA R_X86_64_GLOB_DAT