3.5.7.9 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Kees Cook <[email protected]> commit e70ab977991964a5a7ad1182799451d067e62669 upstream. While PROC_CN_MCAST_LISTEN/IGNORE is entirely advisory, it was possible for an unprivileged user to turn off notifications for all listeners by sending PROC_CN_MCAST_IGNORE. Instead, require the same privileges as required for a multicast bind. Signed-off-by: Kees Cook <[email protected]> Cc: Evgeniy Polyakov <[email protected]> Cc: Matt Helsley <[email protected]> Acked-by: Evgeniy Polyakov <[email protected]> Acked-by: Matt Helsley <[email protected]> Signed-off-by: David S. Miller <[email protected]> [ luis: backported to 3.5 ] Signed-off-by: Luis Henriques <[email protected]> --- drivers/connector/cn_proc.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c index 77e1e6c..9d90e8c 100644 --- a/drivers/connector/cn_proc.c +++ b/drivers/connector/cn_proc.c @@ -303,7 +303,13 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg, if (msg->len != sizeof(*mc_op)) return; - mc_op = (enum proc_cn_mcast_op*)msg->data; + /* Can only change if privileged. */ + if (!capable(CAP_NET_ADMIN)) { + err = EPERM; + goto out; + } + + mc_op = (enum proc_cn_mcast_op *)msg->data; switch (*mc_op) { case PROC_CN_MCAST_LISTEN: atomic_inc(&proc_event_num_listeners); @@ -315,6 +321,8 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg, err = EINVAL; break; } + +out: cn_proc_ack(err, msg->seq, msg->ack); } -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
