install.texi: Build was tested with binutils 2.41 (just released)

[thirdparty/glibc.git] / elf / dl-support.c

diff --git a/elf/dl-support.c b/elf/dl-support.c
index 1977a2be7602650e0b2ef850c777d9b9cc056c52..44a54dea0743c633e2d844841c632ac252c46aea 100644 (file)
--- a/elf/dl-support.c
+++ b/elf/dl-support.c
@@ -1,5 +1,5 @@
 /* Support for dynamic linking code in static libc.
-   Copyright (C) 1996-2022 Free Software Foundation, Inc.
+   Copyright (C) 1996-2023 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
@@ -35,7 +35,6 @@
 #include <dl-machine.h>
 #include <libc-lock.h>
 #include <dl-cache.h>
-#include <dl-librecon.h>
 #include <dl-procinfo.h>
 #include <unsecvars.h>
 #include <hp-timing.h>
@@ -44,6 +43,8 @@
 #include <dl-vdso-setup.h>
 #include <dl-auxv.h>
 #include <dl-find_object.h>
+#include <array_length.h>
+#include <dl-symbol-redir-ifunc.h>
 
 extern char *__progname;
 char **_dl_argv = &__progname; /* This is checked for some error messages.  */
@@ -144,8 +145,6 @@ size_t _dl_minsigstacksize = CONSTANT_MINSIGSTKSZ;
 
 int _dl_inhibit_cache;
 
-unsigned int _dl_osversion;
-
 /* All known directories in sorted order.  */
 struct r_search_path_elem *_dl_all_dirs;
 
@@ -158,8 +157,6 @@ struct link_map *_dl_initfirst;
 /* Descriptor to write debug messages to.  */
 int _dl_debug_fd = STDERR_FILENO;
 
-int _dl_correct_cache_id = _DL_CACHE_DEFAULT_ID;
-
 ElfW(auxv_t) *_dl_auxv;
 const ElfW(Phdr) *_dl_phdr;
 size_t _dl_phnum;
@@ -171,16 +168,6 @@ enum dso_sort_algorithm _dl_dso_sort_algo;
 /* The value of the FPU control word the kernel will preset in hardware.  */
 fpu_control_t _dl_fpu_control = _FPU_DEFAULT;
 
-#if !HAVE_TUNABLES
-/* This is not initialized to HWCAP_IMPORTANT, matching the definition
-   of _dl_important_hwcaps, below, where no hwcap strings are ever
-   used.  This mask is still used to mediate the lookups in the cache
-   file.  Since there is no way to set this nonzero (we don't grok the
-   LD_HWCAP_MASK environment variable here), there is no real point in
-   setting _dl_hwcap nonzero below, but we do anyway.  */
-uint64_t _dl_hwcap_mask;
-#endif
-
 /* Prevailing state of the stack.  Generally this includes PF_X, indicating it's
  * executable but this isn't true for all platforms.  */
 ElfW(Word) _dl_stack_flags = DEFAULT_STACK_PERMS;
@@ -219,7 +206,7 @@ struct link_map *_dl_sysinfo_map;
 #include <dl-vdso-setup.c>
 
 /* During the program run we must not modify the global data of
-   loaded shared object simultanously in two threads.  Therefore we
+   loaded shared object simultaneously in two threads.  Therefore we
    protect `_dl_open' and `_dl_close' in dl-close.c.
 
    This must be a recursive lock since the initializer function of
@@ -253,8 +240,31 @@ _dl_aux_init (ElfW(auxv_t) *av)
 #endif
 
   _dl_auxv = av;
-  dl_parse_auxv_t auxv_values = { 0, };
+  dl_parse_auxv_t auxv_values;
+  /* Use an explicit initialization loop here because memset may not
+     be available yet.  */
+  for (int i = 0; i < array_length (auxv_values); ++i)
+    auxv_values[i] = 0;
   _dl_parse_auxv (av, auxv_values);
+
+  _dl_phdr = (void*) auxv_values[AT_PHDR];
+  _dl_phnum = auxv_values[AT_PHNUM];
+
+  if (_dl_phdr == NULL)
+    {
+      /* Starting from binutils-2.23, the linker will define the
+         magic symbol __ehdr_start to point to our own ELF header
+         if it is visible in a segment that also includes the phdrs.
+         So we can set up _dl_phdr and _dl_phnum even without any
+         information from auxv.  */
+
+      extern const ElfW(Ehdr) __ehdr_start attribute_hidden;
+      assert (__ehdr_start.e_phentsize == sizeof *GL(dl_phdr));
+      _dl_phdr = (const void *) &__ehdr_start + __ehdr_start.e_phoff;
+      _dl_phnum = __ehdr_start.e_phnum;
+    }
+
+  assert (_dl_phdr != NULL);
 }
 #endif
 
@@ -300,50 +310,37 @@ _dl_non_dynamic_init (void)
     {
       static const char unsecure_envvars[] =
        UNSECURE_ENVVARS
-#ifdef EXTRA_UNSECURE_ENVVARS
-       EXTRA_UNSECURE_ENVVARS
-#endif
        ;
       const char *cp = unsecure_envvars;
 
       while (cp < unsecure_envvars + sizeof (unsecure_envvars))
        {
          __unsetenv (cp);
-         cp = (const char *) __rawmemchr (cp, '\0') + 1;
+         cp = strchr (cp, '\0') + 1;
        }
-
-#if !HAVE_TUNABLES
-      if (__access ("/etc/suid-debug", F_OK) != 0)
-       __unsetenv ("MALLOC_CHECK_");
-#endif
     }
 
 #ifdef DL_PLATFORM_INIT
   DL_PLATFORM_INIT;
 #endif
 
-#ifdef DL_OSVERSION_INIT
-  DL_OSVERSION_INIT;
-#endif
-
   /* Now determine the length of the platform string.  */
   if (_dl_platform != NULL)
     _dl_platformlen = strlen (_dl_platform);
 
-  if (_dl_phdr != NULL)
-    for (const ElfW(Phdr) *ph = _dl_phdr; ph < &_dl_phdr[_dl_phnum]; ++ph)
-      switch (ph->p_type)
-       {
-       /* Check if the stack is nonexecutable.  */
-       case PT_GNU_STACK:
-         _dl_stack_flags = ph->p_flags;
-         break;
-
-       case PT_GNU_RELRO:
-         _dl_main_map.l_relro_addr = ph->p_vaddr;
-         _dl_main_map.l_relro_size = ph->p_memsz;
-         break;
-       }
+  for (const ElfW(Phdr) *ph = _dl_phdr; ph < &_dl_phdr[_dl_phnum]; ++ph)
+    switch (ph->p_type)
+      {
+      /* Check if the stack is nonexecutable.  */
+      case PT_GNU_STACK:
+       _dl_stack_flags = ph->p_flags;
+       break;
+
+      case PT_GNU_RELRO:
+       _dl_main_map.l_relro_addr = ph->p_vaddr;
+       _dl_main_map.l_relro_size = ph->p_memsz;
+       break;
+      }
 
   call_function_static_weak (_dl_find_object_init);