From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chuck Ebbert <cebbert@redhat.com>
Subject: Re: BUG in sys_socketpair
Date: Thu, 25 Oct 2007 14:44:52 -0400
Message-ID: <4720E424.7060509@redhat.com>
References: <20071025141107.GA19437@dragon.rich-paul.net>
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Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	Al Viro <viro@ftp.linux.org.uk>
To: Rich Paul <socketpair_bug@rich-paul.net>
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On 10/25/2007 10:11 AM, Rich Paul wrote:
> In 2.6.23, there seems to be a minor bug in sys_socketpair.  When the
> calls to sock_alloc_fd fail, it aborts the routine, but it returns the
> variable err, which is not set in this case.
> 
> The result is a silent failure if you have too many files open and call
> socketpair.
> 
> Here is a simple UNTESTED patch (not even compiled) which should resolve the
> issue.
> 
> 
> --- net/socket.c.orig   2007-10-25 10:03:56.000000000 -0400
> +++ net/socket.c        2007-10-25 10:04:00.000000000 -0400
> @@ -1245,11 +1245,14 @@
>                 goto out_release_both;
> 
>         fd1 = sock_alloc_fd(&newfile1);
> -       if (unlikely(fd1 < 0))
> +       if (unlikely(fd1 < 0)) {
> +               err=fd1;
>                 goto out_release_both;
> +       }
> 
>         fd2 = sock_alloc_fd(&newfile2);
>         if (unlikely(fd2 < 0)) {
> +               err=fd2;
>                 put_filp(newfile1);
>                 put_unused_fd(fd1);
>                 goto out_release_both;
> 

Should be "err = fd1" (spaces), otherwise looks good.

Original did:

	err = sock_map_fd(sock1);
	if (err < 0)
		goto out_release_both;
	fd1 = err;