commit 8f8dd904c4a2207699bb666f30acceb5209c8d3f
Author: Florian Weimer <fweimer@redhat.com>
Date:   Wed Nov 6 10:33:44 2024 +0100

    elf: rtld_multiple_ref is always true

    For a long time, libc.so.6 has dependend on ld.so, which
    means that there is a reference to ld.so in all processes,
    and rtld_multiple_ref is always true.  In fact, if
    rtld_multiple_ref were false, some of the ld.so setup code
    would not run.

    Reviewed-by: DJ Delorie <dj@redhat.com>

Conflicts:
	elf/rtld.c (
	  - prelink support not removed downstream
	  - "elf: Add _dl_find_object function" not ported
	    downstream
	)

diff --git a/elf/rtld.c b/elf/rtld.c
index d02ecc834c9a4d43..711bb77d70da6563 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -2002,43 +2002,37 @@ dl_main (const ElfW(Phdr) *phdr,
     if (main_map->l_searchlist.r_list[i] == &GL(dl_rtld_map))
       break;
 
-  bool rtld_multiple_ref = false;
-  if (__glibc_likely (i < main_map->l_searchlist.r_nlist))
-    {
-      /* Some DT_NEEDED entry referred to the interpreter object itself, so
-	 put it back in the list of visible objects.  We insert it into the
-	 chain in symbol search order because gdb uses the chain's order as
-	 its symbol search order.  */
-      rtld_multiple_ref = true;
+  /* Insert the link map for the dynamic loader into the chain in
+     symbol search order because gdb uses the chain's order as its
+     symbol search order.  */
 
-      GL(dl_rtld_map).l_prev = main_map->l_searchlist.r_list[i - 1];
-      if (__glibc_likely (state.mode == rtld_mode_normal))
-	{
-	  GL(dl_rtld_map).l_next = (i + 1 < main_map->l_searchlist.r_nlist
-				    ? main_map->l_searchlist.r_list[i + 1]
-				    : NULL);
+  GL(dl_rtld_map).l_prev = main_map->l_searchlist.r_list[i - 1];
+  if (__glibc_likely (state.mode == rtld_mode_normal))
+    {
+      GL(dl_rtld_map).l_next = (i + 1 < main_map->l_searchlist.r_nlist
+				? main_map->l_searchlist.r_list[i + 1]
+				: NULL);
 #ifdef NEED_DL_SYSINFO_DSO
-	  if (GLRO(dl_sysinfo_map) != NULL
-	      && GL(dl_rtld_map).l_prev->l_next == GLRO(dl_sysinfo_map)
-	      && GL(dl_rtld_map).l_next != GLRO(dl_sysinfo_map))
-	    GL(dl_rtld_map).l_prev = GLRO(dl_sysinfo_map);
+      if (GLRO(dl_sysinfo_map) != NULL
+	  && GL(dl_rtld_map).l_prev->l_next == GLRO(dl_sysinfo_map)
+	  && GL(dl_rtld_map).l_next != GLRO(dl_sysinfo_map))
+	GL(dl_rtld_map).l_prev = GLRO(dl_sysinfo_map);
 #endif
-	}
-      else
-	/* In trace mode there might be an invisible object (which we
-	   could not find) after the previous one in the search list.
-	   In this case it doesn't matter much where we put the
-	   interpreter object, so we just initialize the list pointer so
-	   that the assertion below holds.  */
-	GL(dl_rtld_map).l_next = GL(dl_rtld_map).l_prev->l_next;
-
-      assert (GL(dl_rtld_map).l_prev->l_next == GL(dl_rtld_map).l_next);
-      GL(dl_rtld_map).l_prev->l_next = &GL(dl_rtld_map);
-      if (GL(dl_rtld_map).l_next != NULL)
-	{
-	  assert (GL(dl_rtld_map).l_next->l_prev == GL(dl_rtld_map).l_prev);
-	  GL(dl_rtld_map).l_next->l_prev = &GL(dl_rtld_map);
-	}
+    }
+  else
+    /* In trace mode there might be an invisible object (which we
+       could not find) after the previous one in the search list.
+       In this case it doesn't matter much where we put the
+       interpreter object, so we just initialize the list pointer so
+       that the assertion below holds.  */
+    GL(dl_rtld_map).l_next = GL(dl_rtld_map).l_prev->l_next;
+
+  assert (GL(dl_rtld_map).l_prev->l_next == GL(dl_rtld_map).l_next);
+  GL(dl_rtld_map).l_prev->l_next = &GL(dl_rtld_map);
+  if (GL(dl_rtld_map).l_next != NULL)
+    {
+      assert (GL(dl_rtld_map).l_next->l_prev == GL(dl_rtld_map).l_prev);
+      GL(dl_rtld_map).l_next->l_prev = &GL(dl_rtld_map);
     }
 
   /* Now let us see whether all libraries are available in the
@@ -2212,8 +2206,7 @@ dl_main (const ElfW(Phdr) *phdr,
 		    }
 		}
 
-	      if ((GLRO(dl_debug_mask) & DL_DEBUG_PRELINK)
-		  && rtld_multiple_ref)
+	      if (GLRO(dl_debug_mask) & DL_DEBUG_PRELINK)
 		{
 		  /* Mark the link map as not yet relocated again.  */
 		  GL(dl_rtld_map).l_relocated = 0;
@@ -2500,10 +2493,9 @@ dl_main (const ElfW(Phdr) *phdr,
   /* Make sure no new search directories have been added.  */
   assert (GLRO(dl_init_all_dirs) == GL(dl_all_dirs));
 
-  if (! prelinked && rtld_multiple_ref)
+  if (! prelinked)
     {
-      /* There was an explicit ref to the dynamic linker as a shared lib.
-	 Re-relocate ourselves with user-controlled symbol definitions.
+      /* Re-relocate ourselves with user-controlled symbol definitions.
 
 	 We must do this after TLS initialization in case after this
 	 re-relocation, we might call a user-supplied function