Smack: Ptrace access check mode

When the ptrace security hooks were split the addition of
a mode parameter was not taken advantage of in the Smack
ptrace access check. This changes the access check from
always looking for read and write access to using the
passed mode. This will make use of /proc much happier.

Targeted for git://git.gitorious.org/smack-next/kernel.gitSigned-off-by: NCasey Schaufler <casey@schaufler-ca.com>

security/smack/smack_lsm.c

@@ -185,7 +185,7 @@ static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
 	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
 	smk_ad_setfield_u_tsk(&ad, ctp);
 
-	rc = smk_curacc(skp->smk_known, MAY_READWRITE, &ad);
+	rc = smk_curacc(skp->smk_known, mode, &ad);
 	return rc;
 }