[BZ #2510, BZ #2830, BZ #3137, BZ #3313, BZ #3426, BZ #3465, BZ #3480, BZ #3483,...

[thirdparty/glibc.git] / nscd / nscd_getpw_r.c

diff --git a/nscd/nscd_getpw_r.c b/nscd/nscd_getpw_r.c
index b84baa1a666f6808819f63cbbddf8bc558e479dc..e8e4d7364faff8b2ed004db2a0271b8cdc6c9ce3 100644 (file)
--- a/nscd/nscd_getpw_r.c
+++ b/nscd/nscd_getpw_r.c
@@ -1,5 +1,4 @@
-/* Copyright (C) 1998, 1999, 2003, 2004, 2005, 2007
-   Free Software Foundation, Inc.
+/* Copyright (C) 1998, 1999, 2003, 2004, 2005 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Thorsten Kukuk <kukuk@uni-paderborn.de>, 1998.
 
@@ -89,81 +88,76 @@ nscd_getpw_r (const char *key, size_t keylen, request_type type,
              struct passwd **result)
 {
   int gc_cycle;
-  int nretries = 0;
-
   /* If the mapping is available, try to search there instead of
      communicating with the nscd.  */
   struct mapped_database *mapped;
   mapped = __nscd_get_map_ref (GETFDPW, "passwd", &map_handle, &gc_cycle);
 
  retry:;
+  const pw_response_header *pw_resp = NULL;
   const char *pw_name = NULL;
   int retval = -1;
   const char *recend = (const char *) ~UINTMAX_C (0);
-  pw_response_header pw_resp;
 
   if (mapped != NO_MAPPING)
     {
-      struct datahead *found = __nscd_cache_search (type, key, keylen, mapped);
+      const struct datahead *found = __nscd_cache_search (type, key, keylen,
+                                                         mapped);
       if (found != NULL)
        {
-         pw_name = (const char *) (&found->data[0].pwdata + 1);
-         pw_resp = found->data[0].pwdata;
+         pw_resp = &found->data[0].pwdata;
+         pw_name = (const char *) (pw_resp + 1);
          recend = (const char *) found->data + found->recsize;
-         /* Now check if we can trust pw_resp fields.  If GC is
-            in progress, it can contain anything.  */
-         if (mapped->head->gc_cycle != gc_cycle)
-           {
-             retval = -2;
-             goto out;
-           }
        }
     }
 
+  pw_response_header pw_resp_mem;
   int sock = -1;
-  if (pw_name == NULL)
+  if (pw_resp == NULL)
     {
-      sock = __nscd_open_socket (key, keylen, type, &pw_resp,
-                                sizeof (pw_resp));
+      sock = __nscd_open_socket (key, keylen, type, &pw_resp_mem,
+                                sizeof (pw_resp_mem));
       if (sock == -1)
        {
          __nss_not_use_nscd_passwd = 1;
          goto out;
        }
+
+      pw_resp = &pw_resp_mem;
     }
 
   /* No value found so far.  */
   *result = NULL;
 
-  if (__builtin_expect (pw_resp.found == -1, 0))
+  if (__builtin_expect (pw_resp->found == -1, 0))
     {
       /* The daemon does not cache this database.  */
       __nss_not_use_nscd_passwd = 1;
       goto out_close;
     }
 
-  if (pw_resp.found == 1)
+  if (pw_resp->found == 1)
     {
       /* Set the information we already have.  */
-      resultbuf->pw_uid = pw_resp.pw_uid;
-      resultbuf->pw_gid = pw_resp.pw_gid;
+      resultbuf->pw_uid = pw_resp->pw_uid;
+      resultbuf->pw_gid = pw_resp->pw_gid;
 
       char *p = buffer;
       /* get pw_name */
       resultbuf->pw_name = p;
-      p += pw_resp.pw_name_len;
+      p += pw_resp->pw_name_len;
       /* get pw_passwd */
       resultbuf->pw_passwd = p;
-      p += pw_resp.pw_passwd_len;
+      p += pw_resp->pw_passwd_len;
       /* get pw_gecos */
       resultbuf->pw_gecos = p;
-      p += pw_resp.pw_gecos_len;
+      p += pw_resp->pw_gecos_len;
       /* get pw_dir */
       resultbuf->pw_dir = p;
-      p += pw_resp.pw_dir_len;
+      p += pw_resp->pw_dir_len;
       /* get pw_pshell */
       resultbuf->pw_shell = p;
-      p += pw_resp.pw_shell_len;
+      p += pw_resp->pw_shell_len;
 
       ssize_t total = p - buffer;
       if (__builtin_expect (pw_name + total > recend, 0))
@@ -195,14 +189,14 @@ nscd_getpw_r (const char *key, size_t keylen, request_type type,
          memcpy (resultbuf->pw_name, pw_name, total);
 
          /* Try to detect corrupt databases.  */
-         if (resultbuf->pw_name[pw_resp.pw_name_len - 1] != '\0'
-             || resultbuf->pw_passwd[pw_resp.pw_passwd_len - 1] != '\0'
-             || resultbuf->pw_gecos[pw_resp.pw_gecos_len - 1] != '\0'
-             || resultbuf->pw_dir[pw_resp.pw_dir_len - 1] != '\0'
-             || resultbuf->pw_shell[pw_resp.pw_shell_len - 1] != '\0')
+         if (resultbuf->pw_name[pw_resp->pw_name_len - 1] != '\0'
+             || resultbuf->pw_passwd[pw_resp->pw_passwd_len - 1] != '\0'
+             || resultbuf->pw_gecos[pw_resp->pw_gecos_len - 1] != '\0'
+             || resultbuf->pw_dir[pw_resp->pw_dir_len - 1] != '\0'
+             || resultbuf->pw_shell[pw_resp->pw_shell_len - 1] != '\0')
            {
              /* We cannot use the database.  */
-             retval = mapped->head->gc_cycle != gc_cycle ? -2 : -1;
+             retval = -1;
              goto out_close;
            }
 
@@ -221,21 +215,19 @@ nscd_getpw_r (const char *key, size_t keylen, request_type type,
   if (sock != -1)
     close_not_cancel_no_status (sock);
  out:
-  if (__nscd_drop_map_ref (mapped, &gc_cycle) != 0)
+  if (__nscd_drop_map_ref (mapped, &gc_cycle) != 0 && retval != -1)
     {
       /* When we come here this means there has been a GC cycle while we
         were looking for the data.  This means the data might have been
         inconsistent.  Retry if possible.  */
-      if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1)
+      if ((gc_cycle & 1) != 0)
        {
          /* nscd is just running gc now.  Disable using the mapping.  */
-         if (atomic_decrement_val (&mapped->counter) == 0)
-           __nscd_unmap (mapped);
+         __nscd_unmap (mapped);
          mapped = NO_MAPPING;
        }
 
-      if (retval != -1)
-       goto retry;
+      goto retry;
     }
 
   return retval;