Smack: Assign smack_known_web label for kernel thread's

Assign smack_known_web label for kernel thread's socket

Creating struct sock by sk_alloc function in various kernel subsystems
like bluetooth doesn't call smack_socket_post_create(). In such case,
received sock label is the floor('_') label and makes access deny.

Signed-off-by: jooseong lee <jooseong.lee@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 1cb060293505..e73460d5acc6 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -2337,8 +2337,16 @@ static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
         if (ssp == NULL)
                 return -ENOMEM;
 
-        ssp->smk_in = skp;
-        ssp->smk_out = skp;
+        /*
+         * Sockets created by kernel threads receive web label.
+         */
+        if (unlikely(current->flags & PF_KTHREAD)) {
+                ssp->smk_in = &smack_known_web;
+                ssp->smk_out = &smack_known_web;
+        } else {
+                ssp->smk_in = skp;
+                ssp->smk_out = skp;
+        }
         ssp->smk_packet = NULL;
 
         sk->sk_security = ssp;