Re: [ 183/184] irda: Fix missing msg_namelen update in

[Ben Hutchings]

On Tue, 2013-06-04 at 19:24 +0200, Willy Tarreau wrote:
> 2.6.32-longterm review patch.  If anyone has any objections, please let me know.
> 
> ------------------
>  irda_recvmsg_dgram()
> 
> From: Mathias Krause <minipli@xxxxxxxxxxxxxx>

commit 5ae94c0d2f0bed41d6718be743985d61b7f5c47d upstream.

> The current code does not fill the msg_name member in case it is set.
> It also does not set the msg_namelen member to 0 and therefore makes
> net/socket.c leak the local, uninitialized sockaddr_storage variable
> to userland -- 128 bytes of kernel stack memory.
> 
> Fix that by simply setting msg_namelen to 0 as obviously nobody cared
> about irda_recvmsg_dgram() not filling the msg_name in case it was
> set.
> 
> Cc: Samuel Ortiz <samuel@xxxxxxxxxx>
> Signed-off-by: Mathias Krause <minipli@xxxxxxxxxxxxxx>
> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
> [dannf: adjusted to apply to Debian's 2.6.32]
> Signed-off-by: Willy Tarreau <w@xxxxxx>
> ---
>  net/irda/af_irda.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/net/irda/af_irda.c b/net/irda/af_irda.c
> index 476b24e..bfb325d 100644
> --- a/net/irda/af_irda.c
> +++ b/net/irda/af_irda.c
> @@ -1338,6 +1338,8 @@ static int irda_recvmsg_dgram(struct kiocb *iocb, struct socket *sock,
>  	if ((err = sock_error(sk)) < 0)
>  		return err;
>  
> +	msg->msg_namelen = 0;
> +
>  	skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
>  				flags & MSG_DONTWAIT, &err);
>  	if (!skb)

-- 
Ben Hutchings
Theory and practice are closer in theory than in practice.
                                - John Levine, moderator of comp.compilers

Attachment: signature.asc
Description: This is a digitally signed message part