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Diffstat (limited to 'sysdeps/unix/sysv/linux/ifaddrs.c')
-rw-r--r--sysdeps/unix/sysv/linux/ifaddrs.c75
1 files changed, 58 insertions, 17 deletions
diff --git a/sysdeps/unix/sysv/linux/ifaddrs.c b/sysdeps/unix/sysv/linux/ifaddrs.c
index 02e6935538..82495de03e 100644
--- a/sysdeps/unix/sysv/linux/ifaddrs.c
+++ b/sysdeps/unix/sysv/linux/ifaddrs.c
@@ -1,5 +1,5 @@
 /* getifaddrs -- get names and addresses of all network interfaces
-   Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+   Copyright (C) 2003, 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
@@ -122,36 +122,36 @@ int
 __netlink_request (struct netlink_handle *h, int type)
 {
   struct netlink_res *nlm_next;
+  struct netlink_res **new_nlm_list;
+  static volatile size_t buf_size = 4096;
+  char *buf;
   struct sockaddr_nl nladdr;
   struct nlmsghdr *nlmh;
   ssize_t read_len;
   bool done = false;
-
-#ifdef PAGE_SIZE
-  /* Help the compiler optimize out the malloc call if PAGE_SIZE
-     is constant and smaller or equal to PTHREAD_STACK_MIN/4.  */
-  const size_t buf_size = PAGE_SIZE;
-#else
-  const size_t buf_size = __getpagesize ();
-#endif
   bool use_malloc = false;
-  char *buf;
 
-  if (__libc_use_alloca (buf_size))
-    buf = alloca (buf_size);
+  if (__netlink_sendreq (h, type) < 0)
+    return -1;
+
+  size_t this_buf_size = buf_size;
+  if (__libc_use_alloca (this_buf_size))
+    buf = alloca (this_buf_size);
   else
     {
-      buf = malloc (buf_size);
+      buf = malloc (this_buf_size);
       if (buf != NULL)
 	use_malloc = true;
       else
 	goto out_fail;
     }
 
-  struct iovec iov = { buf, buf_size };
+  struct iovec iov = { buf, this_buf_size };
 
-  if (__netlink_sendreq (h, type) < 0)
-    goto out_fail;
+  if (h->nlm_list != NULL)
+    new_nlm_list = &h->end_ptr->next;
+  else
+    new_nlm_list = &h->nlm_list;
 
   while (! done)
     {
@@ -171,7 +171,48 @@ __netlink_request (struct netlink_handle *h, int type)
 	continue;
 
       if (__builtin_expect (msg.msg_flags & MSG_TRUNC, 0))
-	goto out_fail;
+	{
+	  if (this_buf_size >= SIZE_MAX / 2)
+	    goto out_fail;
+
+	  nlm_next = *new_nlm_list;
+	  while (nlm_next != NULL)
+	    {
+	      struct netlink_res *tmpptr;
+
+	      tmpptr = nlm_next->next;
+	      free (nlm_next);
+	      nlm_next = tmpptr;
+	    }
+	  *new_nlm_list = NULL;
+
+	  if (__libc_use_alloca (2 * this_buf_size))
+	    buf = extend_alloca (buf, this_buf_size, 2 * this_buf_size);
+	  else
+	    {
+	      this_buf_size *= 2;
+
+	      char *new_buf = realloc (use_malloc ? buf : NULL, this_buf_size);
+	      if (new_buf == NULL)
+		goto out_fail;
+	      new_buf = buf;
+
+	      use_malloc = true;
+	    }
+	  buf_size = this_buf_size;
+
+	  iov.iov_base = buf;
+	  iov.iov_len = this_buf_size;
+
+	  /* Increase sequence number, so that we can distinguish
+	     between old and new request messages.  */
+	  h->seq++;
+
+	  if (__netlink_sendreq (h, type) < 0)
+	    goto out_fail;
+
+	  continue;
+	}
 
       size_t count = 0;
       size_t remaining_len = read_len;