net: Use netlink_ns_capable to verify the permisions of netlink messages
It is possible by passing a netlink socket to a more privileged
executable and then to fool that executable into writing to the socket
data that happens to be valid netlink message to do something that
privileged executable did not intend to do.
To keep this from happening replace bare capable and ns_capable calls
with netlink_capable, netlink_net_calls and netlink_ns_capable calls.
Which act the same as the previous calls except they verify that the
opener of the socket had the desired permissions as well.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
index 1512e41..43665d0 100644
--- a/crypto/crypto_user.c
+++ b/crypto/crypto_user.c
@@ -466,7 +466,7 @@
type -= CRYPTO_MSG_BASE;
link = &crypto_dispatch[type];
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c
index 148d707..ccdd4c7 100644
--- a/drivers/connector/cn_proc.c
+++ b/drivers/connector/cn_proc.c
@@ -369,7 +369,7 @@
return;
/* Can only change if privileged. */
- if (!capable(CAP_NET_ADMIN)) {
+ if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
err = EPERM;
goto out;
}
diff --git a/drivers/scsi/scsi_netlink.c b/drivers/scsi/scsi_netlink.c
index fe30ea9..109802f 100644
--- a/drivers/scsi/scsi_netlink.c
+++ b/drivers/scsi/scsi_netlink.c
@@ -77,7 +77,7 @@
goto next_msg;
}
- if (!capable(CAP_SYS_ADMIN)) {
+ if (!netlink_capable(skb, CAP_SYS_ADMIN)) {
err = -EPERM;
goto next_msg;
}
diff --git a/kernel/audit.c b/kernel/audit.c
index 7c28936..47845c5 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -643,13 +643,13 @@
if ((task_active_pid_ns(current) != &init_pid_ns))
return -EPERM;
- if (!capable(CAP_AUDIT_CONTROL))
+ if (!netlink_capable(skb, CAP_AUDIT_CONTROL))
err = -EPERM;
break;
case AUDIT_USER:
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
- if (!capable(CAP_AUDIT_WRITE))
+ if (!netlink_capable(skb, CAP_AUDIT_WRITE))
err = -EPERM;
break;
default: /* bad msg */
diff --git a/net/can/gw.c b/net/can/gw.c
index ac31891..050a211 100644
--- a/net/can/gw.c
+++ b/net/can/gw.c
@@ -804,7 +804,7 @@
u8 limhops = 0;
int err = 0;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if (nlmsg_len(nlh) < sizeof(*r))
@@ -893,7 +893,7 @@
u8 limhops = 0;
int err = 0;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if (nlmsg_len(nlh) < sizeof(*r))
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index d4ff417..64ad17d 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1395,7 +1395,8 @@
return 0;
}
-static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
+static int do_setlink(const struct sk_buff *skb,
+ struct net_device *dev, struct ifinfomsg *ifm,
struct nlattr **tb, char *ifname, int modified)
{
const struct net_device_ops *ops = dev->netdev_ops;
@@ -1407,7 +1408,7 @@
err = PTR_ERR(net);
goto errout;
}
- if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) {
+ if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) {
err = -EPERM;
goto errout;
}
@@ -1661,7 +1662,7 @@
if (err < 0)
goto errout;
- err = do_setlink(dev, ifm, tb, ifname, 0);
+ err = do_setlink(skb, dev, ifm, tb, ifname, 0);
errout:
return err;
}
@@ -1778,7 +1779,8 @@
}
EXPORT_SYMBOL(rtnl_create_link);
-static int rtnl_group_changelink(struct net *net, int group,
+static int rtnl_group_changelink(const struct sk_buff *skb,
+ struct net *net, int group,
struct ifinfomsg *ifm,
struct nlattr **tb)
{
@@ -1787,7 +1789,7 @@
for_each_netdev(net, dev) {
if (dev->group == group) {
- err = do_setlink(dev, ifm, tb, NULL, 0);
+ err = do_setlink(skb, dev, ifm, tb, NULL, 0);
if (err < 0)
return err;
}
@@ -1929,12 +1931,12 @@
modified = 1;
}
- return do_setlink(dev, ifm, tb, ifname, modified);
+ return do_setlink(skb, dev, ifm, tb, ifname, modified);
}
if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
if (ifm->ifi_index == 0 && tb[IFLA_GROUP])
- return rtnl_group_changelink(net,
+ return rtnl_group_changelink(skb, net,
nla_get_u32(tb[IFLA_GROUP]),
ifm, tb);
return -ENODEV;
@@ -2321,7 +2323,7 @@
int err = -EINVAL;
__u8 *addr;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
@@ -2773,7 +2775,7 @@
sz_idx = type>>2;
kind = type&3;
- if (kind != 2 && !ns_capable(net->user_ns, CAP_NET_ADMIN))
+ if (kind != 2 && !netlink_net_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
diff --git a/net/dcb/dcbnl.c b/net/dcb/dcbnl.c
index 5536444..f8b98d8 100644
--- a/net/dcb/dcbnl.c
+++ b/net/dcb/dcbnl.c
@@ -1669,7 +1669,7 @@
struct nlmsghdr *reply_nlh = NULL;
const struct reply_func *fn;
- if ((nlh->nlmsg_type == RTM_SETDCB) && !capable(CAP_NET_ADMIN))
+ if ((nlh->nlmsg_type == RTM_SETDCB) && !netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
ret = nlmsg_parse(nlh, sizeof(*dcb), tb, DCB_ATTR_MAX,
diff --git a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c
index a603823..3b726f3 100644
--- a/net/decnet/dn_dev.c
+++ b/net/decnet/dn_dev.c
@@ -574,7 +574,7 @@
struct dn_ifaddr __rcu **ifap;
int err = -EINVAL;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if (!net_eq(net, &init_net))
@@ -618,7 +618,7 @@
struct dn_ifaddr *ifa;
int err;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if (!net_eq(net, &init_net))
diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c
index 57dc159..d332aef 100644
--- a/net/decnet/dn_fib.c
+++ b/net/decnet/dn_fib.c
@@ -505,7 +505,7 @@
struct nlattr *attrs[RTA_MAX+1];
int err;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if (!net_eq(net, &init_net))
@@ -530,7 +530,7 @@
struct nlattr *attrs[RTA_MAX+1];
int err;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if (!net_eq(net, &init_net))
diff --git a/net/decnet/netfilter/dn_rtmsg.c b/net/decnet/netfilter/dn_rtmsg.c
index e83015c..e4d9560 100644
--- a/net/decnet/netfilter/dn_rtmsg.c
+++ b/net/decnet/netfilter/dn_rtmsg.c
@@ -107,7 +107,7 @@
if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
return;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
RCV_SKB_FAIL(-EPERM);
/* Eventually we might send routing messages too */
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index e8138da..84392f3 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -375,7 +375,7 @@
skb->len < nlh->nlmsg_len)
return;
- if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) {
+ if (!netlink_net_capable(skb, CAP_NET_ADMIN)) {
netlink_ack(skb, nlh, -EPERM);
return;
}
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index b1dcdb9..a3ba3ca 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -561,7 +561,7 @@
return -EOPNOTSUPP;
if ((ops->flags & GENL_ADMIN_PERM) &&
- !capable(CAP_NET_ADMIN))
+ !netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if ((nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP) {
diff --git a/net/packet/diag.c b/net/packet/diag.c
index b34d0de..92f2c71 100644
--- a/net/packet/diag.c
+++ b/net/packet/diag.c
@@ -194,7 +194,7 @@
net = sock_net(skb->sk);
req = nlmsg_data(cb->nlh);
- may_report_filterinfo = ns_capable(net->user_ns, CAP_NET_ADMIN);
+ may_report_filterinfo = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
mutex_lock(&net->packet.sklist_lock);
sk_for_each(sk, &net->packet.sklist) {
diff --git a/net/phonet/pn_netlink.c b/net/phonet/pn_netlink.c
index dc15f43..b64151a 100644
--- a/net/phonet/pn_netlink.c
+++ b/net/phonet/pn_netlink.c
@@ -70,10 +70,10 @@
int err;
u8 pnaddr;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
- if (!capable(CAP_SYS_ADMIN))
+ if (!netlink_capable(skb, CAP_SYS_ADMIN))
return -EPERM;
ASSERT_RTNL();
@@ -233,10 +233,10 @@
int err;
u8 dst;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
- if (!capable(CAP_SYS_ADMIN))
+ if (!netlink_capable(skb, CAP_SYS_ADMIN))
return -EPERM;
ASSERT_RTNL();
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 8a5ba5a..648778a 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -948,7 +948,7 @@
u32 portid = skb ? NETLINK_CB(skb).portid : 0;
int ret = 0, ovr = 0;
- if ((n->nlmsg_type != RTM_GETACTION) && !capable(CAP_NET_ADMIN))
+ if ((n->nlmsg_type != RTM_GETACTION) && !netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 29a30a1..bdbdb1a 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -134,7 +134,7 @@
int err;
int tp_created = 0;
- if ((n->nlmsg_type != RTM_GETTFILTER) && !capable(CAP_NET_ADMIN))
+ if ((n->nlmsg_type != RTM_GETTFILTER) && !netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
replay:
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index a0b84e0..4007690 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1084,7 +1084,7 @@
struct Qdisc *p = NULL;
int err;
- if ((n->nlmsg_type != RTM_GETQDISC) && !capable(CAP_NET_ADMIN))
+ if ((n->nlmsg_type != RTM_GETQDISC) && !netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
@@ -1151,7 +1151,7 @@
struct Qdisc *q, *p;
int err;
- if (!capable(CAP_NET_ADMIN))
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
replay:
@@ -1490,7 +1490,7 @@
u32 qid;
int err;
- if ((n->nlmsg_type != RTM_GETTCLASS) && !capable(CAP_NET_ADMIN))
+ if ((n->nlmsg_type != RTM_GETTCLASS) && !netlink_capable(skb, CAP_NET_ADMIN))
return -EPERM;
err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
diff --git a/net/tipc/netlink.c b/net/tipc/netlink.c
index 3aaf73d..ad844d3 100644
--- a/net/tipc/netlink.c
+++ b/net/tipc/netlink.c
@@ -47,7 +47,7 @@
int hdr_space = nlmsg_total_size(GENL_HDRLEN + TIPC_GENL_HDRLEN);
u16 cmd;
- if ((req_userhdr->cmd & 0xC000) && (!capable(CAP_NET_ADMIN)))
+ if ((req_userhdr->cmd & 0xC000) && (!netlink_capable(skb, CAP_NET_ADMIN)))
cmd = TIPC_CMD_NOT_NET_ADMIN;
else
cmd = req_userhdr->cmd;
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 8f131c1..51398ae 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2377,7 +2377,7 @@
link = &xfrm_dispatch[type];
/* All operations require privileges, even GET */
- if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+ if (!netlink_net_capable(skb, CAP_NET_ADMIN))
return -EPERM;
if ((type == (XFRM_MSG_GETSA - XFRM_MSG_BASE) ||