BACKPORT: 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>
(cherry-picked from upstream 08382c9f6efe08b8bb30645c2744480cbd8f161a)

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index a0662e65e5d78d93dcc2fb312969c001ff47f748..f5046e27a3242658236150f0d4c7c4e35312f58a 100644 (file)
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -2315,8 +2315,16 @@ 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;