From 292f377160c78213af88b5cc069dbdaa08db17dd Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Jos=C3=A9=20Bollo?= Date: Wed, 2 Nov 2016 11:11:01 +0100 Subject: [PATCH 55/56] Smack: Assign smack_known_web as default smk_in label for kernel thread's socket MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This change fixes the bug associated with sockets owned by kernel threads. These sockets, created usually by network devices' drivers tasks, received smk_in label from the task that created them - the "floor" label in the most cases. The result was that they were not able to receive data packets because of missing smack rules. The main reason of the access deny is that the socket smk_in label is placed as the object during smk check, kernel thread's capabilities are omitted. Refers-to: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7412301b76bd53ee53b860f611fc3b5b1c2245b5 Change-Id: Icec88b0d51133df8d0a09ea8016233bde255af10 Signed-off-by: Marcin Lis Signed-off-by: José Bollo --- security/smack/smack_lsm.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 895fe5c..ff696e7 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -2453,7 +2453,21 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name, static int smack_socket_post_create(struct socket *sock, int family, int type, int protocol, int kern) { - if (family != PF_INET || sock->sk == NULL) + struct socket_smack *ssp; + + if (sock->sk == NULL) + return 0; + + /* + * Sockets created by kernel threads receive web label. + */ + if (unlikely(current->flags & PF_KTHREAD)) { + ssp = sock->sk->sk_security; + ssp->smk_in = &smack_known_web; + ssp->smk_out = &smack_known_web; + } + + if (family != PF_INET) return 0; /* * Set the outbound netlbl. -- 2.7.4