net: Use netlink_ns_capable to verify the permisions of netlink messages

[ Upstream commit 90f62cf30a78721641e08737bda787552428061e ]

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
index 1512e41cd93d74a4e7ab3fde6809e64468f797a8..43665d0d0905ddddf018fe68655c1ff7685b0b9e 100644 (file)
--- a/crypto/crypto_user.c
+++ b/crypto/crypto_user.c
@@ -466,7 +466,7 @@ static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
        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 18c5b9b16645dfa49a218d4b12253240f97310b7..3165811e2407df9bdc8242640dab50558c37db73 100644 (file)
--- a/drivers/connector/cn_proc.c
+++ b/drivers/connector/cn_proc.c
@@ -369,7 +369,7 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg,
                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 fe30ea94ffe67ef4e5d355fdc9cdcb71eee9e0d7..109802f776ed71cea6857eda9ae6ccc3e0b41f80 100644 (file)
--- a/drivers/scsi/scsi_netlink.c
+++ b/drivers/scsi/scsi_netlink.c
@@ -77,7 +77,7 @@ scsi_nl_rcv_msg(struct sk_buff *skb)
                        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 6def25f1b351140fa2258bb164eb284dde01445f..a6c632757e57a3223c8daebf1219d8d94c218120 100644 (file)
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -593,13 +593,13 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
        case AUDIT_TTY_SET:
        case AUDIT_TRIM:
        case AUDIT_MAKE_EQUIV:
-               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 3ee690e8c7d32354a525ad398291b7b7c5155215..de25455b4e3e827bfae94b8a835a69c3191fe569 100644 (file)
--- a/net/can/gw.c
+++ b/net/can/gw.c
@@ -784,7 +784,7 @@ static int cgw_create_job(struct sk_buff *skb,  struct nlmsghdr *nlh)
        struct cgw_job *gwj;
        int err = 0;
 
-       if (!capable(CAP_NET_ADMIN))
+       if (!netlink_capable(skb, CAP_NET_ADMIN))
                return -EPERM;
 
        if (nlmsg_len(nlh) < sizeof(*r))
@@ -876,7 +876,7 @@ static int cgw_remove_job(struct sk_buff *skb,  struct nlmsghdr *nlh)
        struct can_can_gw ccgw;
        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 87ec574ffac8e82c8b482cd9cd138a0362a05c7f..054ebbf73236f5674b594ddcf4a03a331ceaf42a 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1294,7 +1294,8 @@ static int do_set_master(struct net_device *dev, int ifindex)
        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;
@@ -1306,7 +1307,7 @@ static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
                        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;
                }
@@ -1560,7 +1561,7 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh)
        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;
 }
@@ -1678,7 +1679,8 @@ err:
 }
 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)
 {
@@ -1687,7 +1689,7 @@ static int rtnl_group_changelink(struct net *net, int group,
 
        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;
                }
@@ -1789,12 +1791,12 @@ replay:
                                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;
@@ -2179,7 +2181,7 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh)
        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);
@@ -2635,7 +2637,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
        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 40d5829ed36aaa6945c9c4c2056325b68ab64c03..1074ffb6d533993dd0332c04558192ed9d8373a8 100644 (file)
--- a/net/dcb/dcbnl.c
+++ b/net/dcb/dcbnl.c
@@ -1670,7 +1670,7 @@ static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
        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 7d9197063ebb98beee6c778b25c5e675ecedfb4b..b5e52100a89a1ab3ea24b5e697339e7db478218c 100644 (file)
--- a/net/decnet/dn_dev.c
+++ b/net/decnet/dn_dev.c
@@ -573,7 +573,7 @@ static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
        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))
@@ -617,7 +617,7 @@ static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
        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 57dc159245ecfff38e318626cf0ea1ffa9db1cae..d332aefb0846f86a11d924e3e1e7ad23e279dda2 100644 (file)
--- a/net/decnet/dn_fib.c
+++ b/net/decnet/dn_fib.c
@@ -505,7 +505,7 @@ static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
        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 @@ static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
        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 2a7efe388344fdd37b10487c50ba3d712eedbf8a..f3dc69a41d63446d53bb24925c9dad8bdbef5e47 100644 (file)
--- a/net/decnet/netfilter/dn_rtmsg.c
+++ b/net/decnet/netfilter/dn_rtmsg.c
@@ -107,7 +107,7 @@ static inline void dnrmg_receive_user_skb(struct sk_buff *skb)
        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 572d87dc116ffa838d2f9f8838129156add7284e..0a03662bfbefbb41bc433999966196f38d7674bd 100644 (file)
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -147,7 +147,7 @@ static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
        const struct nfnetlink_subsystem *ss;
        int type, err;
 
-       if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+       if (!netlink_net_capable(skb, CAP_NET_ADMIN))
                return -EPERM;
 
        /* All the messages must at least contain nfgenmsg */

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 393f17eea1a2f148a4c48a423c1611553473019c..ade434b8abd883400855d3ddddf2a76e578fe347 100644 (file)
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -592,7 +592,7 @@ static int genl_family_rcv_msg(struct genl_family *family,
                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) {

diff --git a/net/packet/diag.c b/net/packet/diag.c
index 01cd1ac44ff51e11e54756aa4b175ca303c8ff72..674b0a65df6c02eb49d36869c969a1439982ab2e 100644 (file)
--- a/net/packet/diag.c
+++ b/net/packet/diag.c
@@ -193,7 +193,7 @@ static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 
        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 dc15f430080831e74fade00799a661ab10cc6f84..b64151ade6b33a9cbacb0980d3ddbe03d8f7b4c8 100644 (file)
--- a/net/phonet/pn_netlink.c
+++ b/net/phonet/pn_netlink.c
@@ -70,10 +70,10 @@ static int addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
        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 @@ static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
        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 fd7072827a40139c4ffba595aaa261282641e37f..15d46b9166debf2d4b832e4c837e3981b7401606 100644 (file)
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -989,7 +989,7 @@ static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n)
        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 8e118af9097345a500e1006bff6fa5c108435603..2ea40d1877a6cce9230b574463b12c637b8ac86e 100644 (file)
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -138,7 +138,7 @@ static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n)
        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 51b968d3febb477be1e4183c8a94258c97fdcd18..2d2f07945c85a3324275bfbe61f4faf6ccd242ad 100644 (file)
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1024,7 +1024,7 @@ static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
        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);
@@ -1091,7 +1091,7 @@ static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
        struct Qdisc *q, *p;
        int err;
 
-       if (!capable(CAP_NET_ADMIN))
+       if (!netlink_capable(skb, CAP_NET_ADMIN))
                return -EPERM;
 
 replay:
@@ -1431,7 +1431,7 @@ static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n)
        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 8bcd4985d0fb341f795346f06c55d1f059c4c643..1e6081fb60788f35d5413dd799e107652177ba97 100644 (file)
--- a/net/tipc/netlink.c
+++ b/net/tipc/netlink.c
@@ -47,7 +47,7 @@ static int handle_cmd(struct sk_buff *skb, struct genl_info *info)
        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 3f565e495ac68cea83e1d52cf7db7e820fe777ad..7a70a5a5671aa1c592446e3794ccd5b53e59fc1c 100644 (file)
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2362,7 +2362,7 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
        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) ||