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-rw-r--r--elf/dl-runtime.c320
1 files changed, 52 insertions, 268 deletions
diff --git a/elf/dl-runtime.c b/elf/dl-runtime.c
index ee2b8b5f6c..a0aecda2e8 100644
--- a/elf/dl-runtime.c
+++ b/elf/dl-runtime.c
@@ -1,5 +1,5 @@
 /* On-demand PLT fixup for shared objects.
-   Copyright (C) 1995-2006, 2007 Free Software Foundation, Inc.
+   Copyright (C) 1995-2002, 2003, 2004 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
@@ -22,12 +22,8 @@
 #include <alloca.h>
 #include <stdlib.h>
 #include <unistd.h>
-#include <sys/param.h>
 #include <ldsodefs.h>
-#include <sysdep-cancel.h>
 #include "dynamic-link.h"
-#include <tls.h>
-
 
 #if (!defined ELF_MACHINE_NO_RELA && !defined ELF_MACHINE_PLT_REL) \
     || ELF_MACHINE_NO_REL
@@ -55,15 +51,15 @@
    function.  */
 
 #ifndef ELF_MACHINE_NO_PLT
-DL_FIXUP_VALUE_TYPE
-__attribute ((noinline)) ARCH_FIXUP_ATTRIBUTE
-_dl_fixup (
+static ElfW(Addr)
+__attribute ((used, noinline)) ARCH_FIXUP_ATTRIBUTE
+fixup (
 # ifdef ELF_MACHINE_RUNTIME_FIXUP_ARGS
-	   ELF_MACHINE_RUNTIME_FIXUP_ARGS,
+        ELF_MACHINE_RUNTIME_FIXUP_ARGS,
 # endif
-	   /* GKM FIXME: Fix trampoline to pass bounds so we can do
-	      without the `__unbounded' qualifier.  */
-	   struct link_map *__unbounded l, ElfW(Word) reloc_offset)
+	/* GKM FIXME: Fix trampoline to pass bounds so we can do
+	   without the `__unbounded' qualifier.  */
+       struct link_map *__unbounded l, ElfW(Word) reloc_offset)
 {
   const ElfW(Sym) *const symtab
     = (const void *) D_PTR (l, l_info[DT_SYMTAB]);
@@ -74,7 +70,7 @@ _dl_fixup (
   const ElfW(Sym) *sym = &symtab[ELFW(R_SYM) (reloc->r_info)];
   void *const rel_addr = (void *)(l->l_addr + reloc->r_offset);
   lookup_t result;
-  DL_FIXUP_VALUE_TYPE value;
+  ElfW(Addr) value;
 
   /* Sanity check that we're really looking at a PLT relocation.  */
   assert (ELFW(R_TYPE)(reloc->r_info) == ELF_MACHINE_JMP_SLOT);
@@ -84,6 +80,8 @@ _dl_fixup (
   if (__builtin_expect (ELFW(ST_VISIBILITY) (sym->st_other), 0) == 0)
     {
       const struct r_found_version *version = NULL;
+      // XXX Why exactly do we have the differentiation of the flags here?
+      int flags = DL_LOOKUP_ADD_DEPENDENCY;
 
       if (l->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
 	{
@@ -93,35 +91,27 @@ _dl_fixup (
 	  version = &l->l_versions[ndx];
 	  if (version->hash == 0)
 	    version = NULL;
+	  else
+	    flags = 0;
 	}
 
-      /* We need to keep the scope around so do some locking.  This is
-	 not necessary for objects which cannot be unloaded or when
-	 we are not using any threads (yet).  */
-      int flags = DL_LOOKUP_ADD_DEPENDENCY;
-      if (!RTLD_SINGLE_THREAD_P)
-	THREAD_GSCOPE_SET_FLAG ();
-
-      result = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym, l->l_scope,
-				    version, ELF_RTYPE_CLASS_PLT, flags, NULL);
-
-      /* We are done with the global scope.  */
-      if (!RTLD_SINGLE_THREAD_P)
-	THREAD_GSCOPE_RESET_FLAG ();
+      result = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym,
+				    l->l_scope, version, ELF_RTYPE_CLASS_PLT,
+				    DL_LOOKUP_ADD_DEPENDENCY, NULL);
 
       /* Currently result contains the base load address (or link map)
 	 of the object that defines sym.  Now add in the symbol
 	 offset.  */
-      value = DL_FIXUP_MAKE_VALUE (result,
-				   sym ? (LOOKUP_VALUE_ADDRESS (result)
-					  + sym->st_value) : 0);
+      value = (sym ? LOOKUP_VALUE_ADDRESS (result) + sym->st_value : 0);
     }
   else
     {
       /* We already found the symbol.  The module (and therefore its load
 	 address) is also known.  */
-      value = DL_FIXUP_MAKE_VALUE (l, l->l_addr + sym->st_value);
+      value = l->l_addr + sym->st_value;
+#ifdef DL_LOOKUP_RETURNS_MAP
       result = l;
+#endif
     }
 
   /* And now perhaps the relocation addend.  */
@@ -137,45 +127,45 @@ _dl_fixup (
 
 #if !defined PROF && !defined ELF_MACHINE_NO_PLT && !__BOUNDED_POINTERS__
 
-DL_FIXUP_VALUE_TYPE
-__attribute ((noinline)) ARCH_FIXUP_ATTRIBUTE
-_dl_profile_fixup (
+static ElfW(Addr)
+__attribute ((used, noinline)) ARCH_FIXUP_ATTRIBUTE
+profile_fixup (
 #ifdef ELF_MACHINE_RUNTIME_FIXUP_ARGS
-		   ELF_MACHINE_RUNTIME_FIXUP_ARGS,
+       ELF_MACHINE_RUNTIME_FIXUP_ARGS,
 #endif
-		   struct link_map *l, ElfW(Word) reloc_offset,
-		   ElfW(Addr) retaddr, void *regs, long int *framesizep)
+       struct link_map *l, ElfW(Word) reloc_offset, ElfW(Addr) retaddr)
 {
   void (*mcount_fct) (ElfW(Addr), ElfW(Addr)) = INTUSE(_dl_mcount);
+  ElfW(Addr) *resultp;
+  lookup_t result;
+  ElfW(Addr) value;
 
   /* This is the address in the array where we store the result of previous
      relocations.  */
-  struct reloc_result *reloc_result
-    = &l->l_reloc_result[reloc_offset / sizeof (PLTREL)];
-  DL_FIXUP_VALUE_TYPE *resultp = &reloc_result->addr;
+  resultp = &l->l_reloc_result[reloc_offset / sizeof (PLTREL)];
 
-  DL_FIXUP_VALUE_TYPE value = *resultp;
-  if (DL_FIXUP_VALUE_CODE_ADDR (value) == 0)
+  value = *resultp;
+  if (value == 0)
     {
       /* This is the first time we have to relocate this object.  */
       const ElfW(Sym) *const symtab
 	= (const void *) D_PTR (l, l_info[DT_SYMTAB]);
-      const char *strtab = (const char *) D_PTR (l, l_info[DT_STRTAB]);
+      const char *strtab = (const void *) D_PTR (l, l_info[DT_STRTAB]);
 
       const PLTREL *const reloc
 	= (const void *) (D_PTR (l, l_info[DT_JMPREL]) + reloc_offset);
-      const ElfW(Sym) *refsym = &symtab[ELFW(R_SYM) (reloc->r_info)];
-      const ElfW(Sym) *defsym = refsym;
-      lookup_t result;
+      const ElfW(Sym) *sym = &symtab[ELFW(R_SYM) (reloc->r_info)];
 
       /* Sanity check that we're really looking at a PLT relocation.  */
       assert (ELFW(R_TYPE)(reloc->r_info) == ELF_MACHINE_JMP_SLOT);
 
       /* Look up the target symbol.  If the symbol is marked STV_PROTECTED
 	 don't look in the global scope.  */
-      if (__builtin_expect (ELFW(ST_VISIBILITY) (refsym->st_other), 0) == 0)
+      if (__builtin_expect (ELFW(ST_VISIBILITY) (sym->st_other), 0) == 0)
 	{
 	  const struct r_found_version *version = NULL;
+	  // XXX Why exactly do we have the differentiation of the flags here?
+	  int flags = DL_LOOKUP_ADD_DEPENDENCY;
 
 	  if (l->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
 	    {
@@ -185,208 +175,38 @@ _dl_profile_fixup (
 	      version = &l->l_versions[ndx];
 	      if (version->hash == 0)
 		version = NULL;
+	      else
+		flags = 0;
 	    }
 
-	  /* We need to keep the scope around so do some locking.  This is
-	     not necessary for objects which cannot be unloaded or when
-	     we are not using any threads (yet).  */
-	  int flags = DL_LOOKUP_ADD_DEPENDENCY;
-	  if (!RTLD_SINGLE_THREAD_P)
-	    THREAD_GSCOPE_SET_FLAG ();
-
-	  result = _dl_lookup_symbol_x (strtab + refsym->st_name, l,
-					&defsym, l->l_scope, version,
-					ELF_RTYPE_CLASS_PLT, flags, NULL);
-
-	  /* We are done with the global scope.  */
-	  if (!RTLD_SINGLE_THREAD_P)
-	    THREAD_GSCOPE_RESET_FLAG ();
+	  result = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym,
+					l->l_scope, version,
+					ELF_RTYPE_CLASS_PLT,
+					DL_LOOKUP_ADD_DEPENDENCY, NULL);
 
 	  /* Currently result contains the base load address (or link map)
 	     of the object that defines sym.  Now add in the symbol
 	     offset.  */
-	  value = DL_FIXUP_MAKE_VALUE (result,
-				       defsym != NULL
-				       ? LOOKUP_VALUE_ADDRESS (result)
-					 + defsym->st_value : 0);
+	  value = (sym ? LOOKUP_VALUE_ADDRESS (result) + sym->st_value : 0);
 	}
       else
 	{
 	  /* We already found the symbol.  The module (and therefore its load
 	     address) is also known.  */
-	  value = DL_FIXUP_MAKE_VALUE (l, l->l_addr + refsym->st_value);
+	  value = l->l_addr + sym->st_value;
+#ifdef DL_LOOKUP_RETURNS_MAP
 	  result = l;
+#endif
 	}
       /* And now perhaps the relocation addend.  */
       value = elf_machine_plt_value (l, reloc, value);
 
-#ifdef SHARED
-      /* Auditing checkpoint: we have a new binding.  Provide the
-	 auditing libraries the possibility to change the value and
-	 tell us whether further auditing is wanted.  */
-      if (defsym != NULL && GLRO(dl_naudit) > 0)
-	{
-	  reloc_result->bound = result;
-	  /* Compute index of the symbol entry in the symbol table of
-	     the DSO with the definition.  */
-	  reloc_result->boundndx = (defsym
-				    - (ElfW(Sym) *) D_PTR (result,
-							   l_info[DT_SYMTAB]));
-
-	  /* Determine whether any of the two participating DSOs is
-	     interested in auditing.  */
-	  if ((l->l_audit_any_plt | result->l_audit_any_plt) != 0)
-	    {
-	      unsigned int altvalue = 0;
-	      struct audit_ifaces *afct = GLRO(dl_audit);
-	      /* Synthesize a symbol record where the st_value field is
-		 the result.  */
-	      ElfW(Sym) sym = *defsym;
-	      sym.st_value = DL_FIXUP_VALUE_ADDR (value);
-
-	      /* Keep track whether there is any interest in tracing
-		 the call in the lower two bits.  */
-	      assert (DL_NNS * 2 <= sizeof (reloc_result->flags) * 8);
-	      assert ((LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT) == 3);
-	      reloc_result->enterexit = LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT;
-
-	      const char *strtab2 = (const void *) D_PTR (result,
-							  l_info[DT_STRTAB]);
-
-	      for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
-		{
-		  /* XXX Check whether both DSOs must request action or
-		     only one */
-		  if ((l->l_audit[cnt].bindflags & LA_FLG_BINDFROM) != 0
-		      && (result->l_audit[cnt].bindflags & LA_FLG_BINDTO) != 0)
-		    {
-		      unsigned int flags = altvalue;
-		      if (afct->symbind != NULL)
-			{
-			  uintptr_t new_value
-			    = afct->symbind (&sym, reloc_result->boundndx,
-					     &l->l_audit[cnt].cookie,
-					     &result->l_audit[cnt].cookie,
-					     &flags,
-					     strtab2 + defsym->st_name);
-			  if (new_value != (uintptr_t) sym.st_value)
-			    {
-			      altvalue = LA_SYMB_ALTVALUE;
-			      sym.st_value = new_value;
-			    }
-			}
-
-		      /* Remember the results for every audit library and
-			 store a summary in the first two bits.  */
-		      reloc_result->enterexit
-			&= flags & (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT);
-		      reloc_result->enterexit
-			|= ((flags & (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT))
-			    << ((cnt + 1) * 2));
-		    }
-		  else
-		    /* If the bind flags say this auditor is not interested,
-		       set the bits manually.  */
-		    reloc_result->enterexit
-		      |= ((LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT)
-			  << ((cnt + 1) * 2));
-
-		  afct = afct->next;
-		}
-
-	      reloc_result->flags = altvalue;
-	      value = DL_FIXUP_ADDR_VALUE (sym.st_value);
-	    }
-	  else
-	    /* Set all bits since this symbol binding is not interesting.  */
-	    reloc_result->enterexit = (1u << DL_NNS) - 1;
-	}
-#endif
-
       /* Store the result for later runs.  */
       if (__builtin_expect (! GLRO(dl_bind_not), 1))
 	*resultp = value;
     }
 
-  /* By default we do not call the pltexit function.  */
-  long int framesize = -1;
-
-#ifdef SHARED
-  /* Auditing checkpoint: report the PLT entering and allow the
-     auditors to change the value.  */
-  if (DL_FIXUP_VALUE_CODE_ADDR (value) != 0 && GLRO(dl_naudit) > 0
-      /* Don't do anything if no auditor wants to intercept this call.  */
-      && (reloc_result->enterexit & LA_SYMB_NOPLTENTER) == 0)
-    {
-      ElfW(Sym) *defsym = ((ElfW(Sym) *) D_PTR (reloc_result->bound,
-						l_info[DT_SYMTAB])
-			   + reloc_result->boundndx);
-
-      /* Set up the sym parameter.  */
-      ElfW(Sym) sym = *defsym;
-      sym.st_value = DL_FIXUP_VALUE_ADDR (value);
-
-      /* Get the symbol name.  */
-      const char *strtab = (const void *) D_PTR (reloc_result->bound,
-						 l_info[DT_STRTAB]);
-      const char *symname = strtab + sym.st_name;
-
-      /* Keep track of overwritten addresses.  */
-      unsigned int altvalue = reloc_result->flags;
-
-      struct audit_ifaces *afct = GLRO(dl_audit);
-      for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
-	{
- 	  if (afct->ARCH_LA_PLTENTER != NULL
-	      && (reloc_result->enterexit
-		  & (LA_SYMB_NOPLTENTER << (2 * (cnt + 1)))) == 0)
-	    {
-	      unsigned int flags = altvalue;
-	      long int new_framesize = -1;
-	      uintptr_t new_value
-		= afct->ARCH_LA_PLTENTER (&sym, reloc_result->boundndx,
-					  &l->l_audit[cnt].cookie,
-					  &reloc_result->bound->l_audit[cnt].cookie,
-					  regs, &flags, symname,
-					  &new_framesize);
-	      if (new_value != (uintptr_t) sym.st_value)
-		{
-		  altvalue = LA_SYMB_ALTVALUE;
-		  sym.st_value = new_value;
-		}
-
-	      /* Remember the results for every audit library and
-		 store a summary in the first two bits.  */
-	      reloc_result->enterexit
-		|= ((flags & (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT))
-		    << (2 * (cnt + 1)));
-
-	      if ((reloc_result->enterexit & (LA_SYMB_NOPLTEXIT
-					      << (2 * (cnt + 1))))
-		  == 0 && new_framesize != -1 && framesize != -2)
-		{
-		  /* If this is the first call providing information,
-		     use it.  */
-		  if (framesize == -1)
-		    framesize = new_framesize;
-		  /* If two pltenter calls provide conflicting information,
-		     use the larger value.  */
-		  else if (new_framesize != framesize)
-		    framesize = MAX (new_framesize, framesize);
-		}
-	    }
-
-	  afct = afct->next;
-	}
-
-      value = DL_FIXUP_ADDR_VALUE (sym.st_value);
-    }
-#endif
-
-  /* Store the frame size information.  */
-  *framesizep = framesize;
-
-  (*mcount_fct) (retaddr, DL_FIXUP_VALUE_CODE_ADDR (value));
+  (*mcount_fct) (retaddr, value);
 
   return value;
 }
@@ -394,45 +214,9 @@ _dl_profile_fixup (
 #endif /* PROF && ELF_MACHINE_NO_PLT */
 
 
-#include <stdio.h>
-void
-ARCH_FIXUP_ATTRIBUTE
-_dl_call_pltexit (struct link_map *l, ElfW(Word) reloc_offset,
-		  const void *inregs, void *outregs)
-{
-#ifdef SHARED
-  /* This is the address in the array where we store the result of previous
-     relocations.  */
-  // XXX Maybe the bound information must be stored on the stack since
-  // XXX with bind_not a new value could have been stored in the meantime.
-  struct reloc_result *reloc_result
-    = &l->l_reloc_result[reloc_offset / sizeof (PLTREL)];
-  ElfW(Sym) *defsym = ((ElfW(Sym) *) D_PTR (reloc_result->bound,
-					    l_info[DT_SYMTAB])
-		       + reloc_result->boundndx);
-
-  /* Set up the sym parameter.  */
-  ElfW(Sym) sym = *defsym;
-
-  /* Get the symbol name.  */
-  const char *strtab = (const void *) D_PTR (reloc_result->bound,
-					     l_info[DT_STRTAB]);
-  const char *symname = strtab + sym.st_name;
-
-  struct audit_ifaces *afct = GLRO(dl_audit);
-  for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
-    {
-      if (afct->ARCH_LA_PLTEXIT != NULL
-	  && (reloc_result->enterexit
-	      & (LA_SYMB_NOPLTEXIT >> (2 * cnt))) == 0)
-	{
-	  afct->ARCH_LA_PLTEXIT (&sym, reloc_result->boundndx,
-				 &l->l_audit[cnt].cookie,
-				 &reloc_result->bound->l_audit[cnt].cookie,
-				 inregs, outregs, symname);
-	}
+/* This macro is defined in dl-machine.h to define the entry point called
+   by the PLT.  The `fixup' function above does the real work, but a little
+   more twiddling is needed to get the stack right and jump to the address
+   finally resolved.  */
 
-      afct = afct->next;
-    }
-#endif
-}
+ELF_MACHINE_RUNTIME_TRAMPOLINE