Backport removal of __gconv_translit_find

2 files changed, 10 insertions, 173 deletions

diff --git a/README.google b/README.google
index f35eb86071..3a13e160c5 100644
--- a/README.google
+++ b/README.google
@@ -535,3 +535,9 @@ sysdeps/x86_64/fpu/libm-test-ulps
   For b/25873705, backport fix for broken trig functions (PR16623)
   https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=1cadc85813d736f7682fa2eeadae639ab6b66c65
   (stanshebs, backport)
+
+iconv/gconv_trans.c
+  For b/25977570, backport removal of __gconv_translit_find (PR17187)
+  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=a1a6a401ab0a3c9f15fb7eaebbdcee24192254e8
+  (stanshebs, backport)
+
diff --git a/iconv/gconv_trans.c b/iconv/gconv_trans.c
index 1e25854ccf..e0835fc666 100644
--- a/iconv/gconv_trans.c
+++ b/iconv/gconv_trans.c
@@ -238,181 +238,12 @@ __gconv_transliterate (struct __gconv_step *step,
   return __GCONV_ILLEGAL_INPUT;
 }
 
-
-/* Structure to represent results of found (or not) transliteration
-   modules.  */
-struct known_trans
-{
-  /* This structure must remain the first member.  */
-  struct trans_struct info;
-
-  char *fname;
-  void *handle;
-  int open_count;
-};
-
-
-/* Tree with results of previous calls to __gconv_translit_find.  */
-static void *search_tree;
-
-/* We modify global data.   */
-__libc_lock_define_initialized (static, lock);
-
-
-/* Compare two transliteration entries.  */
-static int
-trans_compare (const void *p1, const void *p2)
-{
-  const struct known_trans *s1 = (const struct known_trans *) p1;
-  const struct known_trans *s2 = (const struct known_trans *) p2;
-
-  return strcmp (s1->info.name, s2->info.name);
-}
-
-
-/* Open (maybe reopen) the module named in the struct.  Get the function
-   and data structure pointers we need.  */
-static int
-open_translit (struct known_trans *trans)
-{
-  __gconv_trans_query_fct queryfct;
-
-  trans->handle = __libc_dlopen (trans->fname);
-  if (trans->handle == NULL)
-    /* Not available.  */
-    return 1;
-
-  /* Find the required symbol.  */
-  queryfct = __libc_dlsym (trans->handle, "gconv_trans_context");
-  if (queryfct == NULL)
-    {
-      /* We cannot live with that.  */
-    close_and_out:
-      __libc_dlclose (trans->handle);
-      trans->handle = NULL;
-      return 1;
-    }
-
-  /* Get the context.  */
-  if (queryfct (trans->info.name, &trans->info.csnames, &trans->info.ncsnames)
-      != 0)
-    goto close_and_out;
-
-  /* Of course we also have to have the actual function.  */
-  trans->info.trans_fct = __libc_dlsym (trans->handle, "gconv_trans");
-  if (trans->info.trans_fct == NULL)
-    goto close_and_out;
-
-  /* Now the optional functions.  */
-  trans->info.trans_init_fct =
-    __libc_dlsym (trans->handle, "gconv_trans_init");
-  trans->info.trans_context_fct =
-    __libc_dlsym (trans->handle, "gconv_trans_context");
-  trans->info.trans_end_fct =
-    __libc_dlsym (trans->handle, "gconv_trans_end");
-
-  trans->open_count = 1;
-
-  return 0;
-}
-
-
 int
 internal_function
 __gconv_translit_find (struct trans_struct *trans)
 {
-  struct known_trans **found;
-  const struct path_elem *runp;
-  int res = 1;
-
-  /* We have to have a name.  */
-  assert (trans->name != NULL);
-
-  /* Acquire the lock.  */
-  __libc_lock_lock (lock);
-
-  /* See whether we know this module already.  */
-  found = __tfind (trans, &search_tree, trans_compare);
-  if (found != NULL)
-    {
-      /* Is this module available?  */
-      if ((*found)->handle != NULL)
-	{
-	  /* Maybe we have to reopen the file.  */
-	  if ((*found)->handle != (void *) -1)
-	    /* The object is not unloaded.  */
-	    res = 0;
-	  else if (open_translit (*found) == 0)
-	    {
-	      /* Copy the data.  */
-	      *trans = (*found)->info;
-	      (*found)->open_count++;
-	      res = 0;
-	    }
-	}
-    }
-  else
-    {
-      size_t name_len = strlen (trans->name) + 1;
-      int need_so = 0;
-      struct known_trans *newp;
-
-      /* We have to continue looking for the module.  */
-      if (__gconv_path_elem == NULL)
-	__gconv_get_path ();
-
-      /* See whether we have to append .so.  */
-      if (name_len <= 4 || memcmp (&trans->name[name_len - 4], ".so", 3) != 0)
-	need_so = 1;
-
-      /* Create a new entry.  */
-      newp = (struct known_trans *) malloc (sizeof (struct known_trans)
-					    + (__gconv_max_path_elem_len
-					       + name_len + 3)
-					    + name_len);
-      if (newp != NULL)
-	{
-	  char *cp;
-
-	  /* Clear the struct.  */
-	  memset (newp, '\0', sizeof (struct known_trans));
-
-	  /* Store a copy of the module name.  */
-	  newp->info.name = cp = (char *) (newp + 1);
-	  cp = __mempcpy (cp, trans->name, name_len);
-
-	  newp->fname = cp;
-
-	  /* Search in all the directories.  */
-	  for (runp = __gconv_path_elem; runp->name != NULL; ++runp)
-	    {
-	      cp = __mempcpy (__stpcpy ((char *) newp->fname, runp->name),
-			      trans->name, name_len);
-	      if (need_so)
-		memcpy (cp, ".so", sizeof (".so"));
-
-	      if (open_translit (newp) == 0)
-		{
-		  /* We found a module.  */
-		  res = 0;
-		  break;
-		}
-	    }
-
-	  if (res)
-	    newp->fname = NULL;
-
-	  /* In any case we'll add the entry to our search tree.  */
-	  if (__tsearch (newp, &search_tree, trans_compare) == NULL)
-	    {
-	      /* Yickes, this should not happen.  Unload the object.  */
-	      res = 1;
-	      /* XXX unload here.  */
-	    }
-	}
-    }
-
-  __libc_lock_unlock (lock);
-
-  return res;
+  /* Transliteration module loading has been removed because it never
+     worked as intended and suffered from a security vulnerability.
+     Consequently, this function always fails.  */
+  return 1;
 }