commit f6a54a304223666ea4af73260c99c830d7726eca

Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>

Date:   Fri Oct 15 14:35:31 2021 -0300

    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.

    (cherry picked from commit 5118dcac68c4eadfd6304bb33adde63d062dc07f)

    Resolved conflicts:

            elf/rtld.c - Manual merge.

diff --git a/elf/dl-load.c b/elf/dl-load.c

index fb3da5aa565908a6..a920b12a906a9dec 100644

--- a/elf/dl-load.c

+++ b/elf/dl-load.c

@@ -1296,7 +1296,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,

   if (l->l_ld != 0)

     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 ababafcf98f9945d..757205affe65d9e1 100644

--- 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 1ac0663d1ff5de24..f63e07dc6d2cd5e6 100644

--- 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 37d28d5a66d7b5d6..ad5ddb2a0ab94e7f 100644

--- a/elf/rtld.c

+++ b/elf/rtld.c

@@ -549,7 +549,7 @@ _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 ();

   bootstrap_map.l_ld_readonly = DL_RO_DYN_SECTION;

-  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;

@@ -1653,7 +1653,7 @@ 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 f44748bc9858e5fd..3f20578046de76ed 100644

--- 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;