Commit c7051eb3 authored Nov 18, 2018 by Xin Long Committed by Greg Kroah-Hartman Nov 23, 2018

sctp: not allow to set asoc prsctp_enable by sockopt



[ Upstream commit cc3ccf26f0649089b3a34a2781977755ea36e72c ]

As rfc7496#section4.5 says about SCTP_PR_SUPPORTED:

   This socket option allows the enabling or disabling of the
   negotiation of PR-SCTP support for future associations.  For existing
   associations, it allows one to query whether or not PR-SCTP support
   was negotiated on a particular association.

It means only sctp sock's prsctp_enable can be set.

Note that for the limitation of SCTP_{CURRENT|ALL}_ASSOC, we will
add it when introducing SCTP_{FUTURE|CURRENT|ALL}_ASSOC for linux
sctp in another patchset.

v1->v2:
  - drop the params.assoc_id check as Neil suggested.

Fixes: 28aa4c26 ("sctp: add SCTP_PR_SUPPORTED on sctp sockopt")
Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 8b9c0eb1

net/sctp/socket.c

+5 −21

Original line number	Diff line number	Diff line
		@@ -3750,32 +3750,16 @@ static int sctp_setsockopt_pr_supported(struct sock *sk,
		unsigned int optlen)
		{
		struct sctp_assoc_value params;
		struct sctp_association *asoc;
		int retval = -EINVAL;

		if (optlen != sizeof(params))
		goto out;

		if (copy_from_user(&params, optval, optlen)) {
		retval = -EFAULT;
		goto out;
		}

		asoc = sctp_id2assoc(sk, params.assoc_id);
		if (asoc) {
		asoc->prsctp_enable = !!params.assoc_value;
		} else if (!params.assoc_id) {
		struct sctp_sock *sp = sctp_sk(sk);
		return -EINVAL;

		sp->ep->prsctp_enable = !!params.assoc_value;
		} else {
		goto out;
		}
		if (copy_from_user(&params, optval, optlen))
		return -EFAULT;

		retval = 0;
		sctp_sk(sk)->ep->prsctp_enable = !!params.assoc_value;

		out:
		return retval;
		return 0;
		}

		static int sctp_setsockopt_default_prinfo(struct sock *sk,