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-rw-r--r--elf/dl-addr.c236
1 files changed, 113 insertions, 123 deletions
diff --git a/elf/dl-addr.c b/elf/dl-addr.c
index 7dbf716cfa..e55dc4b46f 100644
--- a/elf/dl-addr.c
+++ b/elf/dl-addr.c
@@ -1,5 +1,5 @@
 /* Locate the shared object symbol nearest a given address.
-   Copyright (C) 1996-2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+   Copyright (C) 1996-2004, 2005, 2006 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
@@ -22,149 +22,139 @@
 #include <ldsodefs.h>
 
 
-static void
-__attribute ((always_inline))
-determine_info (const ElfW(Addr) addr, struct link_map *match, Dl_info *info,
-		struct link_map **mapp, const ElfW(Sym) **symbolp)
+int
+internal_function
+_dl_addr (const void *address, Dl_info *info,
+	  struct link_map **mapp, const ElfW(Sym) **symbolp)
 {
-  /* Now we know what object the address lies in.  */
-  info->dli_fname = match->l_name;
-  info->dli_fbase = (void *) match->l_map_start;
-
-  /* If this is the main program the information is incomplete.  */
-  if (__builtin_expect (match->l_name[0], 'a') == '\0'
-      && match->l_type == lt_executable)
-    info->dli_fname = _dl_argv[0];
-
-  const ElfW(Sym) *symtab
-    = (const ElfW(Sym) *) D_PTR (match, l_info[DT_SYMTAB]);
-  const char *strtab = (const char *) D_PTR (match, l_info[DT_STRTAB]);
+  const ElfW(Addr) addr = DL_LOOKUP_ADDRESS (address);
 
-  ElfW(Word) strtabsize = match->l_info[DT_STRSZ]->d_un.d_val;
+  /* Protect against concurrent loads and unloads.  */
+  __rtld_lock_lock_recursive (GL(dl_load_lock));
 
-  const ElfW(Sym) *matchsym = NULL;
-  if (match->l_info[DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM + DT_THISPROCNUM
-		    + DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM] != NULL)
-    {
-      /* We look at all symbol table entries referenced by the hash
-	 table.  */
-      for (Elf_Symndx bucket = 0; bucket < match->l_nbuckets; ++bucket)
+  /* Find the highest-addressed object that ADDRESS is not below.  */
+  struct link_map *match = NULL;
+  for (Lmid_t ns = 0; ns < DL_NNS; ++ns)
+    for (struct link_map *l = GL(dl_ns)[ns]._ns_loaded; l; l = l->l_next)
+      if (addr >= l->l_map_start && addr < l->l_map_end)
 	{
-	  Elf32_Word symndx = match->l_gnu_buckets[bucket];
-	  if (symndx != 0)
+	  /* We know ADDRESS lies within L if in any shared object.
+	     Make sure it isn't past the end of L's segments.  */
+	  size_t n = l->l_phnum;
+	  if (n > 0)
 	    {
-	      const Elf32_Word *hasharr = &match->l_gnu_chain_zero[symndx];
-
 	      do
-		{
-		  /* The hash table never references local symbols so
-		     we can omit that test here.  */
-		  if ((symtab[symndx].st_shndx != SHN_UNDEF
-		       || symtab[symndx].st_value != 0)
-#ifdef USE_TLS
-		      && ELFW(ST_TYPE) (symtab[symndx].st_info) != STT_TLS
-#endif
-		      && DL_ADDR_SYM_MATCH (match, &symtab[symndx],
-					    matchsym, addr)
-		      && symtab[symndx].st_name < strtabsize)
-		    matchsym = (ElfW(Sym) *) &symtab[symndx];
-
-		  ++symndx;
-		}
-	      while ((*hasharr++ & 1u) == 0);
+		--n;
+	      while (l->l_phdr[n].p_type != PT_LOAD);
+	      if (addr >= (l->l_addr +
+			   l->l_phdr[n].p_vaddr + l->l_phdr[n].p_memsz))
+		/* Off the end of the highest-addressed shared object.  */
+		continue;
 	    }
+
+	  match = l;
+	  break;
 	}
-    }
-  else
+
+  int result = 0;
+  if (match != NULL)
     {
-      const ElfW(Sym) *symtabend;
-      if (match->l_info[DT_HASH] != NULL)
-	symtabend = (symtab
-		     + ((Elf_Symndx *) D_PTR (match, l_info[DT_HASH]))[1]);
-      else
-	/* There is no direct way to determine the number of symbols in the
-	   dynamic symbol table and no hash table is present.  The ELF
-	   binary is ill-formed but what shall we do?  Use the beginning of
-	   the string table which generally follows the symbol table.  */
-	symtabend = (const ElfW(Sym) *) strtab;
-
-      for (; (void *) symtab < (void *) symtabend; ++symtab)
-	if ((ELFW(ST_BIND) (symtab->st_info) == STB_GLOBAL
-	     || ELFW(ST_BIND) (symtab->st_info) == STB_WEAK)
-#ifdef USE_TLS
-	    && ELFW(ST_TYPE) (symtab->st_info) != STT_TLS
-#endif
-	    && (symtab->st_shndx != SHN_UNDEF
-		|| symtab->st_value != 0)
-	    && DL_ADDR_SYM_MATCH (match, symtab, matchsym, addr)
-	    && symtab->st_name < strtabsize)
-	  matchsym = (ElfW(Sym) *) symtab;
-    }
+      /* Now we know what object the address lies in.  */
+      info->dli_fname = match->l_name;
+      info->dli_fbase = (void *) match->l_map_start;
 
-  if (mapp)
-    *mapp = match;
-  if (symbolp)
-    *symbolp = matchsym;
+      /* If this is the main program the information is incomplete.  */
+      if (__builtin_expect (match->l_name[0], 'a') == '\0'
+	  && match->l_type == lt_executable)
+	info->dli_fname = _dl_argv[0];
 
-  if (matchsym)
-    {
-      /* We found a symbol close by.  Fill in its name and exact
-	 address.  */
-      lookup_t matchl = LOOKUP_VALUE (match);
+      const ElfW(Sym) *symtab
+	= (const ElfW(Sym) *) D_PTR (match, l_info[DT_SYMTAB]);
+      const char *strtab = (const char *) D_PTR (match, l_info[DT_STRTAB]);
 
-      info->dli_sname = strtab + matchsym->st_name;
-      info->dli_saddr = DL_SYMBOL_ADDRESS (matchl, matchsym);
-    }
-  else
-    {
-      /* No symbol matches.  We return only the containing object.  */
-      info->dli_sname = NULL;
-      info->dli_saddr = NULL;
-    }
-}
+      ElfW(Word) strtabsize = match->l_info[DT_STRSZ]->d_un.d_val;
 
+      const ElfW(Sym) *matchsym = NULL;
+      if (match->l_info[DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM + DT_THISPROCNUM
+			+ DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM] != NULL)
+	{
+	  /* We look at all symbol table entries referenced by the
+	     hash table.  */
+	  for (Elf_Symndx bucket = 0; bucket < match->l_nbuckets; ++bucket)
+	    {
+	      Elf32_Word symndx = match->l_gnu_buckets[bucket];
+	      if (symndx != 0)
+		{
+		  const Elf32_Word *hasharr = &match->l_gnu_chain_zero[symndx];
+
+		  do
+		    {
+		      /* The hash table never references local symbols
+			 so we can omit that test here.  */
+		      if ((symtab[symndx].st_shndx != SHN_UNDEF
+			   || symtab[symndx].st_value != 0)
+			  && ELFW(ST_TYPE) (symtab[symndx].st_info) != STT_TLS
+			  && DL_ADDR_SYM_MATCH (match, &symtab[symndx],
+						matchsym, addr)
+			  && symtab[symndx].st_name < strtabsize)
+			matchsym = (ElfW(Sym) *) &symtab[symndx];
+
+		      ++symndx;
+		    }
+		  while ((*hasharr++ & 1u) == 0);
+		}
+	    }
+	}
+      else
+	{
+	  const ElfW(Sym) *symtabend;
+	  if (match->l_info[DT_HASH] != NULL)
+	    symtabend = (symtab
+			 + ((Elf_Symndx *) D_PTR (match, l_info[DT_HASH]))[1]);
+	  else
+	    /* There is no direct way to determine the number of symbols in the
+	       dynamic symbol table and no hash table is present.  The ELF
+	       binary is ill-formed but what shall we do?  Use the beginning of
+	       the string table which generally follows the symbol table.  */
+	    symtabend = (const ElfW(Sym) *) strtab;
+
+	  for (; (void *) symtab < (void *) symtabend; ++symtab)
+	    if ((ELFW(ST_BIND) (symtab->st_info) == STB_GLOBAL
+		 || ELFW(ST_BIND) (symtab->st_info) == STB_WEAK)
+		&& ELFW(ST_TYPE) (symtab->st_info) != STT_TLS
+		&& (symtab->st_shndx != SHN_UNDEF
+		    || symtab->st_value != 0)
+		&& DL_ADDR_SYM_MATCH (match, symtab, matchsym, addr)
+		&& symtab->st_name < strtabsize)
+	      matchsym = (ElfW(Sym) *) symtab;
+	}
 
-int
-internal_function
-_dl_addr (const void *address, Dl_info *info,
-	  struct link_map **mapp, const ElfW(Sym) **symbolp)
-{
-  const ElfW(Addr) addr = DL_LOOKUP_ADDRESS (address);
-  int result = 0;
+      if (mapp)
+	*mapp = match;
+      if (symbolp)
+	*symbolp = matchsym;
 
-  /* Protect against concurrent loads and unloads.  */
-  __rtld_lock_lock_recursive (GL(dl_load_lock));
+      if (matchsym)
+	{
+	  /* We found a symbol close by.  Fill in its name and exact
+	     address.  */
+	  lookup_t matchl = LOOKUP_VALUE (match);
 
-  /* Find the highest-addressed object that ADDRESS is not below.  */
-  for (Lmid_t ns = 0; ns < DL_NNS; ++ns)
-    for (struct link_map *l = GL(dl_ns)[ns]._ns_loaded; l; l = l->l_next)
-      if (addr >= l->l_map_start && addr < l->l_map_end
-	  && (l->l_contiguous || _dl_addr_inside_object (l, addr)))
+	  info->dli_sname = strtab + matchsym->st_name;
+	  info->dli_saddr = DL_SYMBOL_ADDRESS (matchl, matchsym);
+	}
+      else
 	{
-	  determine_info (addr, l, info, mapp, symbolp);
-	  result = 1;
-	  goto out;
+	  /* No symbol matches.  We return only the containing object.  */
+	  info->dli_sname = NULL;
+	  info->dli_saddr = NULL;
 	}
 
- out:
+      result = 1;
+    }
+
   __rtld_lock_unlock_recursive (GL(dl_load_lock));
 
   return result;
 }
 libc_hidden_def (_dl_addr)
-
-/* Return non-zero if ADDR lies within one of L's segments.  */
-int
-internal_function
-_dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr)
-{
-  int n = l->l_phnum;
-  const ElfW(Addr) reladdr = addr - l->l_addr;
-
-  while (--n >= 0)
-    if (l->l_phdr[n].p_type == PT_LOAD
-	&& reladdr - l->l_phdr[n].p_vaddr >= 0
-	&& reladdr - l->l_phdr[n].p_vaddr < l->l_phdr[n].p_memsz)
-      return 1;
-  return 0;
-}