inet: Return EAI_MEMORY when nrl_domainname() fails to allocate memory

It aligns NI_NOFQDN with default behavior for getnameinfo().

Checked on x86_64-linux-gnu.

diff --git a/inet/getnameinfo.c b/inet/getnameinfo.c
index d3387dd16a1f0bf0155ffff5d74c3aa175c816b0..4733be6f5b64bd3efa11e8b8f1b74be12fd1e622 100644 (file)
--- a/inet/getnameinfo.c
+++ b/inet/getnameinfo.c
@@ -83,94 +83,97 @@ libc_freeres_ptr (static char *domain);
    now ignored.  */
 #define DEPRECATED_NI_IDN 192
 
-static void
+/* Return true if no memory allocation failure happened (even if domain
+   name could not be obtained) or false otherwise.  */
+static bool
 nrl_domainname_core (struct scratch_buffer *tmpbuf)
 {
   char *c;
   struct hostent *h, th;
   int herror;
 
-  while (__gethostbyname_r ("localhost", &th,
-                           tmpbuf->data, tmpbuf->length,
+  while (__gethostbyname_r ("localhost", &th, tmpbuf->data, tmpbuf->length,
                            &h, &herror))
     {
       if (herror == NETDB_INTERNAL && errno == ERANGE)
        {
          if (!scratch_buffer_grow (tmpbuf))
-           return;
+           return false;
        }
       else
        break;
     }
 
   if (h != NULL && (c = strchr (h->h_name, '.')) != NULL)
-    domain = __strdup (++c);
-  else
     {
-      /* The name contains no domain information.  Use the name
-        now to get more information.  */
-      while (__gethostname (tmpbuf->data, tmpbuf->length))
-       if (!scratch_buffer_grow (tmpbuf))
-         return;
-
-      if ((c = strchr (tmpbuf->data, '.')) != NULL)
-       domain = __strdup (++c);
-      else
-       {
-         /* We need to preserve the hostname.  */
-         size_t hstnamelen = strlen (tmpbuf->data) + 1;
-         while (__gethostbyname_r (tmpbuf->data, &th,
-                                   tmpbuf->data + hstnamelen,
-                                   tmpbuf->length - hstnamelen,
-                                   &h, &herror))
-           {
-             if (herror == NETDB_INTERNAL && errno == ERANGE)
-               {
-                 if (!scratch_buffer_grow_preserve (tmpbuf))
-                   return;
-               }
-             else
-               break;
-           }
+      domain = __strdup (++c);
+      return domain != NULL;
+    }
 
-         if (h != NULL && (c = strchr(h->h_name, '.')) != NULL)
-           domain = __strdup (++c);
-         else
-           {
-             struct in_addr in_addr;
+  /* The name contains no domain information.  Use the name
+     now to get more information.  */
+  while (__gethostname (tmpbuf->data, tmpbuf->length))
+    if (!scratch_buffer_grow (tmpbuf))
+      return false;
 
-             in_addr.s_addr = htonl (INADDR_LOOPBACK);
+  if ((c = strchr (tmpbuf->data, '.')) != NULL)
+    {
+      domain = __strdup (++c);
+      return domain != NULL;
+    }
 
-             while (__gethostbyaddr_r ((const char *) &in_addr,
-                                       sizeof (struct in_addr),
-                                       AF_INET, &th,
-                                       tmpbuf->data,
-                                       tmpbuf->length,
-                                       &h, &herror))
-               {
-                 if (herror == NETDB_INTERNAL && errno == ERANGE)
-                   {
-                     if (!scratch_buffer_grow (tmpbuf))
-                       return;
-                   }
-                 else
-                   break;
-               }
+  /* We need to preserve the hostname.  */
+  size_t hstnamelen = strlen (tmpbuf->data) + 1;
+  while (__gethostbyname_r (tmpbuf->data, &th, tmpbuf->data + hstnamelen,
+                           tmpbuf->length - hstnamelen, &h, &herror))
+    {
+      if (herror == NETDB_INTERNAL && errno == ERANGE)
+       {
+         if (!scratch_buffer_grow_preserve (tmpbuf))
+           return false;
+       }
+      else
+       break;
+    }
 
-             if (h != NULL && (c = strchr (h->h_name, '.')) != NULL)
-               domain = __strdup (++c);
-           }
+  if (h != NULL && (c = strchr(h->h_name, '.')) != NULL)
+    {
+      domain = __strdup (++c);
+      return domain != NULL;
+    }
+
+  struct in_addr in_addr = { .s_addr = htonl (INADDR_LOOPBACK) };
+
+  while (__gethostbyaddr_r ((const char *) &in_addr, sizeof (struct in_addr),
+                           AF_INET, &th, tmpbuf->data, tmpbuf->length, &h,
+                           &herror))
+    {
+      if (herror == NETDB_INTERNAL && errno == ERANGE)
+       {
+         if (!scratch_buffer_grow (tmpbuf))
+           return false;
        }
+      else
+       break;
+    }
+
+  if (h != NULL && (c = strchr (h->h_name, '.')) != NULL)
+    {
+      domain = __strdup (++c);
+      return domain != NULL;
     }
+  return true;
 }
 
-static char *
+static bool
 nrl_domainname (void)
 {
   static int not_first;
 
   if (__glibc_likely (atomic_load_acquire (&not_first) != 0))
-    return domain;
+    return true;
+
+  int r = true;
 
   __libc_lock_define_initialized (static, lock);
   __libc_lock_lock (lock);
@@ -180,16 +183,15 @@ nrl_domainname (void)
       struct scratch_buffer tmpbuf;
       scratch_buffer_init (&tmpbuf);
 
-      nrl_domainname_core (&tmpbuf);
+      if ((r = nrl_domainname_core (&tmpbuf)))
+       atomic_store_release (&not_first, 1);
 
       scratch_buffer_free (&tmpbuf);
-
-      atomic_store_release (&not_first, 1);
     }
 
   __libc_lock_unlock (lock);
 
-  return domain;
+  return r;
 };
 
 /* Copy a string to a destination buffer with length checking.  Return
@@ -285,13 +287,17 @@ gni_host_inet_name (struct scratch_buffer *tmpbuf,
 
   if (h)
     {
-      char *c;
-      if ((flags & NI_NOFQDN)
-         && (c = nrl_domainname ())
-         && (c = strstr (h->h_name, c))
-         && (c != h->h_name) && (*(--c) == '.'))
-       /* Terminate the string after the prefix.  */
-       *c = '\0';
+      if (flags & NI_NOFQDN)
+       {
+         if (!nrl_domainname ())
+           return EAI_MEMORY;
+
+         char *c = domain;
+         if (c != NULL && (c = strstr (h->h_name, c))
+              && (c != h->h_name) && (*(--c) == '.'))
+           /* Terminate the string after the prefix.  */
+           *c = '\0';
+       }
 
       /* If requested, convert from the IDN format.  */
       bool do_idn = flags & NI_IDN;