elf: Fix elf_get_dynamic_info() for bootstrap

THe d6d89608ac8c broke powerpc for --enable-bind-now because it turned
out that different than patch assumption rtld elf_get_dynamic_info()
does require to handle RTLD_BOOTSTRAP to avoid DT_FLAGS and
DT_RUNPATH (more specially the GLRO usage which is not reallocate
yet).

This patch fixes by passing two arguments to elf_get_dynamic_info()
to inform that by rtld (bootstrap) or static pie initialization
(static_pie_bootstrap).  I think using explicit argument is way more
clear and burried C preprocessor, and compiler should remove the
dead code.

I checked on x86_64 and i686 with default options, --enable-bind-now,
and --enable-bind-now and --enable--static-pie.  I also check on
aarch64, armhf, powerpc64, and powerpc with default and
--enable-bind-now.

diff --git a/elf/dl-load.c b/elf/dl-load.c
index 18d3e8fe64bef38e570c6e64d7924613d48d5bc9..a1f16821888bf4ed0d6d9181f687965beb642af3 100644 (file)
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -1298,7 +1298,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
   else
     l->l_ld = (ElfW(Dyn) *) ((ElfW(Addr)) l->l_ld + l->l_addr);
 
-  elf_get_dynamic_info (l);
+  elf_get_dynamic_info (l, false, false);
 
   /* Make sure we are not dlopen'ing an object that has the
      DF_1_NOOPEN flag set, or a PIE object.  */

diff --git a/elf/dl-reloc-static-pie.c b/elf/dl-reloc-static-pie.c
index 40a031f2e9ec7604c5d4d1c12186b31602246042..5b85df8a2eed188839d4b8b6cd20532e56a75411 100644 (file)
--- a/elf/dl-reloc-static-pie.c
+++ b/elf/dl-reloc-static-pie.c
@@ -25,7 +25,6 @@
 
 #include <dl-machine.h>
 
-#define STATIC_PIE_BOOTSTRAP
 #define RESOLVE_MAP(map, scope, sym, version, flags) map
 #include "dynamic-link.h"
 #include "get-dynamic-info.h"
@@ -52,7 +51,7 @@ _dl_relocate_static_pie (void)
        break;
       }
 
-  elf_get_dynamic_info (main_map);
+  elf_get_dynamic_info (main_map, false, true);
 
 # ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
   ELF_MACHINE_BEFORE_RTLD_RELOC (main_map, main_map->l_info);

diff --git a/elf/get-dynamic-info.h b/elf/get-dynamic-info.h
index 1ac0663d1ff5de24df18338ecf6f500e7c87a0dd..f63e07dc6d2cd5e61a055cec87b368f3a284f248 100644 (file)
--- a/elf/get-dynamic-info.h
+++ b/elf/get-dynamic-info.h
@@ -26,7 +26,8 @@
 #include <libc-diag.h>
 
 static inline void __attribute__ ((unused, always_inline))
-elf_get_dynamic_info (struct link_map *l)
+elf_get_dynamic_info (struct link_map *l, bool bootstrap,
+                     bool static_pie_bootstrap)
 {
 #if __ELF_NATIVE_CLASS == 32
   typedef Elf32_Word d_tag_utype;
@@ -35,7 +36,7 @@ elf_get_dynamic_info (struct link_map *l)
 #endif
 
 #ifndef STATIC_PIE_BOOTSTRAP
-  if (l->l_ld == NULL)
+  if (!bootstrap && l->l_ld == NULL)
     return;
 #endif
 
@@ -112,47 +113,63 @@ elf_get_dynamic_info (struct link_map *l)
   if (info[DT_REL] != NULL)
     assert (info[DT_RELENT]->d_un.d_val == sizeof (ElfW(Rel)));
 #endif
-#ifdef STATIC_PIE_BOOTSTRAP
-  assert (info[DT_RUNPATH] == NULL);
-  assert (info[DT_RPATH] == NULL);
-#endif
-  if (info[DT_FLAGS] != NULL)
+  if (bootstrap || static_pie_bootstrap)
     {
-      /* Flags are used.  Translate to the old form where available.
-        Since these l_info entries are only tested for NULL pointers it
-        is ok if they point to the DT_FLAGS entry.  */
-      l->l_flags = info[DT_FLAGS]->d_un.d_val;
-
-      if (l->l_flags & DF_SYMBOLIC)
-       info[DT_SYMBOLIC] = info[DT_FLAGS];
-      if (l->l_flags & DF_TEXTREL)
-       info[DT_TEXTREL] = info[DT_FLAGS];
-      if (l->l_flags & DF_BIND_NOW)
-       info[DT_BIND_NOW] = info[DT_FLAGS];
+      assert (info[DT_RUNPATH] == NULL);
+      assert (info[DT_RPATH] == NULL);
     }
-  if (info[VERSYMIDX (DT_FLAGS_1)] != NULL)
+  if (bootstrap)
     {
-      l->l_flags_1 = info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val;
-      if (l->l_flags_1 & DF_1_NODELETE)
-       l->l_nodelete_pending = true;
-
-      /* Only DT_1_SUPPORTED_MASK bits are supported, and we would like
-        to assert this, but we can't. Users have been setting
-        unsupported DF_1_* flags for a long time and glibc has ignored
-        them. Therefore to avoid breaking existing applications the
-        best we can do is add a warning during debugging with the
-        intent of notifying the user of the problem.  */
-      if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0)
-         && l->l_flags_1 & ~DT_1_SUPPORTED_MASK)
-       _dl_debug_printf ("\nWARNING: Unsupported flag value(s) of 0x%x in DT_FLAGS_1.\n",
-                         l->l_flags_1 & ~DT_1_SUPPORTED_MASK);
-
-      if (l->l_flags_1 & DF_1_NOW)
-       info[DT_BIND_NOW] = info[VERSYMIDX (DT_FLAGS_1)];
+      /* Only the bind now flags are allowed.  */
+      assert (info[VERSYMIDX (DT_FLAGS_1)] == NULL
+             || (info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val & ~DF_1_NOW) == 0);
+      /* Flags must not be set for ld.so.  */
+      assert (info[DT_FLAGS] == NULL
+             || (info[DT_FLAGS]->d_un.d_val & ~DF_BIND_NOW) == 0);
     }
-  if (info[DT_RUNPATH] != NULL)
-    /* If both RUNPATH and RPATH are given, the latter is ignored.  */
-    info[DT_RPATH] = NULL;
+  else
+    {
+      if (info[DT_FLAGS] != NULL)
+       {
+         /* Flags are used.  Translate to the old form where available.
+            Since these l_info entries are only tested for NULL pointers it
+            is ok if they point to the DT_FLAGS entry.  */
+         l->l_flags = info[DT_FLAGS]->d_un.d_val;
+
+         if (l->l_flags & DF_SYMBOLIC)
+           info[DT_SYMBOLIC] = info[DT_FLAGS];
+         if (l->l_flags & DF_TEXTREL)
+           info[DT_TEXTREL] = info[DT_FLAGS];
+         if (l->l_flags & DF_BIND_NOW)
+           info[DT_BIND_NOW] = info[DT_FLAGS];
+       }
+
+      if (info[VERSYMIDX (DT_FLAGS_1)] != NULL)
+       {
+         l->l_flags_1 = info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val;
+         if (l->l_flags_1 & DF_1_NODELETE)
+           l->l_nodelete_pending = true;
+
+         /* Only DT_1_SUPPORTED_MASK bits are supported, and we would like
+            to assert this, but we can't. Users have been setting
+            unsupported DF_1_* flags for a long time and glibc has ignored
+            them. Therefore to avoid breaking existing applications the
+            best we can do is add a warning during debugging with the
+            intent of notifying the user of the problem.  */
+         if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0)
+             && l->l_flags_1 & ~DT_1_SUPPORTED_MASK)
+           _dl_debug_printf ("\nWARNING: Unsupported flag value(s) of 0x%x "
+                             "in DT_FLAGS_1.\n",
+                            l->l_flags_1 & ~DT_1_SUPPORTED_MASK);
+
+        if (l->l_flags_1 & DF_1_NOW)
+          info[DT_BIND_NOW] = info[VERSYMIDX (DT_FLAGS_1)];
+       }
+
+    if (info[DT_RUNPATH] != NULL)
+      /* If both RUNPATH and RPATH are given, the latter is ignored.  */
+      info[DT_RPATH] = NULL;
+   }
 }
 
 #endif

diff --git a/elf/rtld.c b/elf/rtld.c
index 6cfb7cf672b33722e5f387f3e827430fd1010857..c66a1d00bcd99eac4eee897fe5c34d67bd2edc20 100644 (file)
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -547,7 +547,7 @@ _dl_start (void *arg)
 
   /* Read our own dynamic section and fill in the info array.  */
   bootstrap_map.l_ld = (void *) bootstrap_map.l_addr + elf_machine_dynamic ();
-  elf_get_dynamic_info (&bootstrap_map);
+  elf_get_dynamic_info (&bootstrap_map, true, false);
 
 #if NO_TLS_OFFSET != 0
   bootstrap_map.l_tls_offset = NO_TLS_OFFSET;
@@ -1615,7 +1615,7 @@ dl_main (const ElfW(Phdr) *phdr,
   if (! rtld_is_main)
     {
       /* Extract the contents of the dynamic section for easy access.  */
-      elf_get_dynamic_info (main_map);
+      elf_get_dynamic_info (main_map, false, false);
 
       /* If the main map is libc.so, update the base namespace to
         refer to this map.  If libc.so is loaded later, this happens

diff --git a/elf/setup-vdso.h b/elf/setup-vdso.h
index f44748bc9858e5fd3d4cf76738700f8f259a7db2..3f20578046de76ed1b91ec10bc76c2e489f3179b 100644 (file)
--- a/elf/setup-vdso.h
+++ b/elf/setup-vdso.h
@@ -64,7 +64,7 @@ setup_vdso (struct link_map *main_map __attribute__ ((unused)),
       l->l_map_end += l->l_addr;
       l->l_text_end += l->l_addr;
       l->l_ld = (void *) ((ElfW(Addr)) l->l_ld + l->l_addr);
-      elf_get_dynamic_info (l);
+      elf_get_dynamic_info (l, false, false);
       _dl_setup_hash (l);
       l->l_relocated = 1;