diff options
| author | Kees Cook <keescook@chromium.org> | 2013-02-25 21:32:25 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-02-27 13:08:35 -0500 |
| commit | e70ab977991964a5a7ad1182799451d067e62669 (patch) | |
| tree | 1026f098ea84df13f0d94e5397d3a5ec6f913aeb | |
| parent | 114a6f8b52163c0232fbcd7f3808ff04dc61a9b5 (diff) | |
proc connector: reject unprivileged listener bumps
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 <keescook@chromium.org>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: stable@vger.kernel.org
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Acked-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/connector/cn_proc.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c index fce2000eec31..1110478dd0fd 100644 --- a/drivers/connector/cn_proc.c +++ b/drivers/connector/cn_proc.c @@ -313,6 +313,12 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg, (task_active_pid_ns(current) != &init_pid_ns)) return; + /* 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: @@ -325,6 +331,8 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg, err = EINVAL; break; } + +out: cn_proc_ack(err, msg->seq, msg->ack); } |