1 files changed, 55 insertions, 59 deletions

diff --git a/nis/nss_nis/nis-rpc.c b/nis/nss_nis/nis-rpc.c
index 162f3572bf..e7049ffa9f 100644
--- a/nis/nss_nis/nis-rpc.c
+++ b/nis/nss_nis/nis-rpc.c
@@ -36,59 +36,22 @@
 
 __libc_lock_define_initialized (static, lock)
 
-struct response_t
-{
-  struct response_t *next;
-  char val[0];
-};
-
-struct intern_t
-{
-  struct response_t *start;
-  struct response_t *next;
-};
-typedef struct intern_t intern_t;
-
-static intern_t intern = {NULL, NULL};
+static intern_t intern;
 
-static int
-saveit (int instatus, char *inkey, int inkeylen, char *inval,
-        int invallen, char *indata)
-{
-  intern_t *intern = (intern_t *) indata;
-
-  if (instatus != YP_TRUE)
-    return 1;
-
-  if (inkey && inkeylen > 0 && inval && invallen > 0)
-    {
-      struct response_t *newp = malloc (sizeof (struct response_t)
-					+ invallen + 1);
-      if (newp == NULL)
-	return 1; /* We have no error code for out of memory */
-
-      if (intern->start == NULL)
-	intern->start = newp;
-      else
-	intern->next->next = newp;
-      intern->next = newp;
-
-      newp->next = NULL;
-      *((char *) mempcpy (newp->val, inval, invallen)) = '\0';
-    }
-
-  return 0;
-}
 
 static void
 internal_nis_endrpcent (intern_t *intern)
 {
-  while (intern->start != NULL)
+  struct response_t *curr = intern->next;
+
+  while (curr != NULL)
     {
-      intern->next = intern->start;
-      intern->start = intern->start->next;
-      free (intern->next);
+      struct response_t *last = curr;
+      curr = curr->next;
+      free (last);
     }
+
+  intern->next = intern->start = NULL;
 }
 
 static enum nss_status
@@ -103,10 +66,16 @@ internal_nis_setrpcent (intern_t *intern)
 
   internal_nis_endrpcent (intern);
 
-  ypcb.foreach = saveit;
-  ypcb.data = (char *)intern;
-  status = yperr2nss (yp_all(domainname, "rpc.bynumber", &ypcb));
+  ypcb.foreach = _nis_saveit;
+  ypcb.data = (char *) intern;
+  status = yperr2nss (yp_all (domainname, "rpc.bynumber", &ypcb));
+
+  /* Mark the last buffer as full.  */
+  if (intern->next != NULL)
+    intern->next->size = intern->offset;
+
   intern->next = intern->start;
+  intern->offset = 0;
 
   return status;
 }
@@ -139,29 +108,56 @@ _nss_nis_endrpcent (void)
 
 static enum nss_status
 internal_nis_getrpcent_r (struct rpcent *rpc, char *buffer, size_t buflen,
-			  int *errnop, intern_t *data)
+			  int *errnop, intern_t *intern)
 {
   struct parser_data *pdata = (void *) buffer;
   int parse_res;
   char *p;
 
-  if (data->start == NULL)
-    internal_nis_setrpcent (data);
+  if (intern->start == NULL)
+    internal_nis_setrpcent (intern);
 
   /* Get the next entry until we found a correct one. */
   do
     {
-      if (data->next == NULL)
-	return NSS_STATUS_NOTFOUND;
+      struct response_t *bucket = intern->next;
+
+      if (__builtin_expect (intern->offset >= bucket->size, 0))
+	{
+	  if (bucket->next == NULL)
+	    return NSS_STATUS_NOTFOUND;
+
+	  /* We look at all the content in the current bucket.  Go on
+	     to the next.  */
+	  bucket = intern->next = bucket->next;
+	  intern->offset = 0;
+	}
+
+      for (p = &bucket->mem[intern->offset]; isspace (*p); ++p)
+        ++intern->offset;
 
-      p = strncpy (buffer, data->next->val, buflen);
-      while (isspace (*p))
-        ++p;
+      size_t len = strlen (p) + 1;
+      if (__builtin_expect (len > buflen, 0))
+	{
+	  *errnop = ERANGE;
+	  return NSS_STATUS_TRYAGAIN;
+	}
+
+      /* We unfortunately have to copy the data in the user-provided
+	 buffer because that buffer might be around for a very long
+	 time and the servent structure must remain valid.  If we would
+	 rely on the BUCKET memory the next 'setservent' or 'endservent'
+	 call would destroy it.
+
+	 The important thing is that it is a single NUL-terminated
+	 string.  This is what the parsing routine expects.  */
+      p = memcpy (buffer, &bucket->mem[intern->offset], len);
 
       parse_res = _nss_files_parse_rpcent (p, rpc, pdata, buflen, errnop);
       if (__builtin_expect (parse_res == -1, 0))
 	return NSS_STATUS_TRYAGAIN;
-      data->next = data->next->next;
+
+      intern->offset += len;
     }
   while (!parse_res);
 
@@ -193,7 +189,7 @@ _nss_nis_getrpcbyname_r (const char *name, struct rpcent *rpc,
       return NSS_STATUS_UNAVAIL;
     }
 
-  intern_t data = { NULL, NULL };
+  intern_t data = { NULL, NULL, 0 };
   enum nss_status status = internal_nis_setrpcent (&data);
   if (__builtin_expect (status != NSS_STATUS_SUCCESS, 0))
     return status;