kcm: return immediately after copy_from_user() failure
BugLink: http://bugs.launchpad.net/bugs/1688499
[ Upstream commit
a80db69e47d764bbcaf2fec54b1f308925e7c490 ]
There is no reason to continue after a copy_from_user()
failure.
Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>