scm: Stop passing struct cred

Now that uids and gids are completely encapsulated in kuid_t
and kgid_t we no longer need to pass struct cred which allowed
us to test both the uid and the user namespace for equality.

Passing struct cred potentially allows us to pass the entire group
list as BSD does but I don't believe the cost of cache line misses
justifies retaining code for a future potential application.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric W. Biederman 2013-04-03 17:28:16 +00:00 committed by David S. Miller
parent d978a6361a
commit 6b0ee8c036
4 changed files with 16 additions and 35 deletions

View file

@ -1340,7 +1340,6 @@ static void unix_destruct_scm(struct sk_buff *skb)
struct scm_cookie scm;
memset(&scm, 0, sizeof(scm));
scm.pid = UNIXCB(skb).pid;
scm.cred = UNIXCB(skb).cred;
if (UNIXCB(skb).fp)
unix_detach_fds(&scm, skb);
@ -1391,8 +1390,8 @@ static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool sen
int err = 0;
UNIXCB(skb).pid = get_pid(scm->pid);
if (scm->cred)
UNIXCB(skb).cred = get_cred(scm->cred);
UNIXCB(skb).uid = scm->creds.uid;
UNIXCB(skb).gid = scm->creds.gid;
UNIXCB(skb).fp = NULL;
if (scm->fp && send_fds)
err = unix_attach_fds(scm, skb);
@ -1409,13 +1408,13 @@ static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool sen
static void maybe_add_creds(struct sk_buff *skb, const struct socket *sock,
const struct sock *other)
{
if (UNIXCB(skb).cred)
if (UNIXCB(skb).pid)
return;
if (test_bit(SOCK_PASSCRED, &sock->flags) ||
!other->sk_socket ||
test_bit(SOCK_PASSCRED, &other->sk_socket->flags)) {
UNIXCB(skb).pid = get_pid(task_tgid(current));
UNIXCB(skb).cred = get_current_cred();
current_euid_egid(&UNIXCB(skb).uid, &UNIXCB(skb).gid);
}
}
@ -1819,7 +1818,7 @@ static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock,
siocb->scm = &tmp_scm;
memset(&tmp_scm, 0, sizeof(tmp_scm));
}
scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred);
scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid);
unix_set_secdata(siocb->scm, skb);
if (!(flags & MSG_PEEK)) {
@ -1991,11 +1990,12 @@ again:
if (check_creds) {
/* Never glue messages from different writers */
if ((UNIXCB(skb).pid != siocb->scm->pid) ||
(UNIXCB(skb).cred != siocb->scm->cred))
!uid_eq(UNIXCB(skb).uid, siocb->scm->creds.uid) ||
!gid_eq(UNIXCB(skb).gid, siocb->scm->creds.gid))
break;
} else if (test_bit(SOCK_PASSCRED, &sock->flags)) {
/* Copy credentials */
scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred);
scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid);
check_creds = 1;
}