[BZ #16046] Static dlopen correction fallout fixes.

Fixes to address issues from BZ #15022 resolution, as follows:

* TLS updates to csu/libc-tls.c -- we now have a proper main map, so
  there's no longer a need to create a separate fake one to keep TLS
  structures,

* random updates to elf/dl-close.c -- LM_ID_BASE is now a valid name
  space ID for static executables as well, so assert that we don't
  unload the main map.  Similarly dl_nns isn't supposed to be 0 for
  static executables anymore,

* actual BZ #16046 fix to elf/dl-iteratephdr.c -- the dl_iterate_phdr
  special function for static executables isn't needed anymore, provided
  that l_phdr and l_phnum members of the main map have been properly
  initialized (done in _dl_non_dynamic_init in elf/dl-support.c now),

* ld.so.cache loader update to elf/dl-load.c --
  GL(dl_ns)[LM_ID_BASE]._ns_loaded is now always initialized in static
  executables so can become the fallback loader map to check for
  DF_1_NODEFLIB, provided that the l_flags_1 member of the main map has
  been properly initialized (done in elf/dl-support.c now); this also
  ensures previous semantics elsewhere in elf/dl-load.c,

* matching updates to elf/dl-support.c -- to complement the two fixes
  above.

1 files changed, 12 insertions, 15 deletions

diff --git a/csu/libc-tls.c b/csu/libc-tls.c
index 5aec47d..c18b888 100644
--- a/csu/libc-tls.c
+++ b/csu/libc-tls.c
@@ -42,9 +42,6 @@ static struct
   struct dtv_slotinfo info[2 + TLS_SLOTINFO_SURPLUS];
 } static_slotinfo;
 
-/* Fake link map for the application.  */
-static struct link_map static_map;
-
 
 /* Highest dtv index currently needed.  */
 size_t _dl_tls_max_dtv_idx;
@@ -162,14 +159,16 @@ __libc_setup_tls (size_t tcbsize, size_t tcbalign)
   _dl_static_dtv[0].counter = (sizeof (_dl_static_dtv) / sizeof (_dl_static_dtv[0])) - 2;
   // _dl_static_dtv[1].counter = 0;		would be needed if not already done
 
+  struct link_map *main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
+
   /* Initialize the TLS block.  */
 #if TLS_TCB_AT_TP
   _dl_static_dtv[2].pointer.val = ((char *) tlsblock + tcb_offset
 			       - roundup (memsz, align ?: 1));
-  static_map.l_tls_offset = roundup (memsz, align ?: 1);
+  main_map->l_tls_offset = roundup (memsz, align ?: 1);
 #elif TLS_DTV_AT_TP
   _dl_static_dtv[2].pointer.val = (char *) tlsblock + tcb_offset;
-  static_map.l_tls_offset = tcb_offset;
+  main_map->l_tls_offset = tcb_offset;
 #else
 # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
 #endif
@@ -193,19 +192,17 @@ __libc_setup_tls (size_t tcbsize, size_t tcbalign)
   if (__builtin_expect (lossage != NULL, 0))
     __libc_fatal (lossage);
 
-  /* We have to create a fake link map which normally would be created
-     by the dynamic linker.  It just has to have enough information to
-     make the TLS routines happy.  */
-  static_map.l_tls_align = align;
-  static_map.l_tls_blocksize = memsz;
-  static_map.l_tls_initimage = initimage;
-  static_map.l_tls_initimage_size = filesz;
-  static_map.l_type = lt_executable;
-  static_map.l_tls_modid = 1;
+  /* Update the executable's link map with enough information to make
+     the TLS routines happy.  */
+  main_map->l_tls_align = align;
+  main_map->l_tls_blocksize = memsz;
+  main_map->l_tls_initimage = initimage;
+  main_map->l_tls_initimage_size = filesz;
+  main_map->l_tls_modid = 1;
 
   init_slotinfo ();
   // static_slotinfo.si.slotinfo[1].gen = 0; already zero
-  static_slotinfo.si.slotinfo[1].map = &static_map;
+  static_slotinfo.si.slotinfo[1].map = main_map;
 
   memsz = roundup (memsz, align ?: 1);