From: Serge Hallyn <serge@hallyn.com>
To: linux-kernel@vger.kernel.org
Cc: dhowells@redhat.com, ebiederm@xmission.com,
containers@lists.linux-foundation.org, netdev@vger.kernel.org,
akpm@osdl.org, "Serge E. Hallyn" <serge.hallyn@canonical.com>
Subject: [PATCH 10/14] net/core/scm.c: target capable() calls to user_ns owning the net_ns
Date: Tue, 26 Jul 2011 18:58:33 +0000 [thread overview]
Message-ID: <1311706717-7398-11-git-send-email-serge@hallyn.com> (raw)
In-Reply-To: <1311706717-7398-1-git-send-email-serge@hallyn.com>
From: Serge E. Hallyn <serge.hallyn@canonical.com>
The uid/gid comparisons don't have to be pulled out. This just seemed
more easily proved correct.
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
---
net/core/scm.c | 41 ++++++++++++++++++++++++++++++++++-------
1 files changed, 34 insertions(+), 7 deletions(-)
diff --git a/net/core/scm.c b/net/core/scm.c
index 4c1ef02..21b5d0b 100644
--- a/net/core/scm.c
+++ b/net/core/scm.c
@@ -43,17 +43,44 @@
* setu(g)id.
*/
-static __inline__ int scm_check_creds(struct ucred *creds)
+static __inline__ bool uidequiv(struct cred *src, struct ucred *tgt,
+ struct user_namespace *ns)
+{
+ if (src->user_ns != ns)
+ goto check_capable;
+ if (src->uid == tgt->uid || src->euid == tgt->uid ||
+ src->suid == tgt->uid)
+ return true;
+check_capable:
+ if (ns_capable(ns, CAP_SETUID))
+ return true;
+ return false;
+}
+
+static __inline__ bool gidequiv(struct cred *src, struct ucred *tgt,
+ struct user_namespace *ns)
+{
+ if (src->user_ns != ns)
+ goto check_capable;
+ if (src->gid == tgt->gid || src->egid == tgt->gid ||
+ src->sgid == tgt->gid)
+ return true;
+check_capable:
+ if (ns_capable(ns, CAP_SETGID))
+ return true;
+ return false;
+}
+
+static __inline__ int scm_check_creds(struct ucred *creds, struct socket *sock)
{
const struct cred *cred = current_cred();
+ struct user_namespace *ns = sock_net(sock->sk)->user_ns;
- if ((creds->pid == task_tgid_vnr(current) || capable(CAP_SYS_ADMIN)) &&
- ((creds->uid == cred->uid || creds->uid == cred->euid ||
- creds->uid == cred->suid) || capable(CAP_SETUID)) &&
- ((creds->gid == cred->gid || creds->gid == cred->egid ||
- creds->gid == cred->sgid) || capable(CAP_SETGID))) {
+ if ((creds->pid == task_tgid_vnr(current) || ns_capable(ns, CAP_SYS_ADMIN)) &&
+ uidequiv(cred, creds, ns) && gidequiv(cred, creds, ns)) {
return 0;
}
+
return -EPERM;
}
@@ -169,7 +196,7 @@ int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *p)
if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct ucred)))
goto error;
memcpy(&p->creds, CMSG_DATA(cmsg), sizeof(struct ucred));
- err = scm_check_creds(&p->creds);
+ err = scm_check_creds(&p->creds, sock);
if (err)
goto error;
--
1.7.4.1
next prev parent reply other threads:[~2011-07-26 18:58 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-26 18:58 [PATCH 0/14] user namespaces v2: continue targetting capabilities Serge Hallyn
2011-07-26 18:58 ` [PATCH 01/14] add Documentation/namespaces/user_namespace.txt Serge Hallyn
2011-07-26 20:22 ` Randy Dunlap
2011-07-27 15:38 ` Serge E. Hallyn
2011-07-27 16:02 ` Randy Dunlap
2011-07-26 20:29 ` David Howells
2011-07-29 17:25 ` [PATCH 01/14] add Documentation/namespaces/user_namespace.txt (v3) Serge E. Hallyn
2011-07-26 18:58 ` [PATCH 02/14] allow root in container to copy namespaces Serge Hallyn
2011-07-27 23:14 ` Eric W. Biederman
2011-07-28 2:13 ` Serge E. Hallyn
2011-07-29 17:27 ` [PATCH 02/14] allow root in container to copy namespaces (v3) Serge E. Hallyn
2011-08-01 22:25 ` Eric W. Biederman
[not found] ` <m1ei146a6t.fsf-+imSwln9KH6u2/kzUuoCbdi2O/JbrIOy@public.gmane.org>
2011-08-02 14:08 ` Serge E. Hallyn
2011-08-02 22:03 ` Eric W. Biederman
2011-08-04 22:01 ` Serge E. Hallyn
2011-07-26 18:58 ` [PATCH 03/14] keyctl: check capabilities against key's user_ns Serge Hallyn
2011-07-26 18:58 ` [PATCH 04/14] user_ns: convert fs/attr.c to targeted capabilities Serge Hallyn
2011-07-26 18:58 ` [PATCH 05/14] userns: clamp down users of cap_raised Serge Hallyn
2011-07-28 23:23 ` Vasiliy Kulikov
2011-07-28 23:51 ` Serge E. Hallyn
2011-07-26 18:58 ` [PATCH 06/14] user namespace: make each net (net_ns) belong to a user_ns Serge Hallyn
2011-07-26 18:58 ` [PATCH 07/14] user namespace: use net->user_ns for some capable calls under net/ Serge Hallyn
2011-07-26 18:58 ` [PATCH 08/14] af_netlink.c: make netlink_capable userns-aware Serge Hallyn
2011-07-26 18:58 ` [PATCH 09/14] user ns: convert ipv6 to targeted capabilities Serge Hallyn
2011-07-26 18:58 ` Serge Hallyn [this message]
2011-08-04 22:06 ` [PATCH 10/14] net/core/scm.c: target capable() calls to user_ns owning the net_ns Serge E. Hallyn
2011-07-26 18:58 ` [PATCH 11/14] userns: make some net-sysfs capable calls targeted Serge Hallyn
2011-07-26 18:58 ` [PATCH 12/14] user_ns: target af_key capability check Serge Hallyn
2011-07-26 18:58 ` [PATCH 13/14] userns: net: make many network capable calls targeted Serge Hallyn
2011-07-26 18:58 ` [PATCH 14/14] net: pass user_ns to cap_netlink_recv() Serge Hallyn
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