[IPv4]: Convert route get to new netlink api
Fixes various unvalidated netlink attributes causing memory
corruptions when left empty by userspace applications.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index 42ed96f..fcc159a 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -216,6 +216,7 @@
#endif /* CONFIG_IP_MULTIPLE_TABLES */
/* Exported by fib_frontend.c */
+extern struct nla_policy rtm_ipv4_policy[];
extern void ip_fib_init(void);
extern int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
extern int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index d537c93..d0abeab 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -453,7 +453,7 @@
#endif
-static struct nla_policy rtm_ipv4_policy[RTA_MAX+1] __read_mostly = {
+struct nla_policy rtm_ipv4_policy[RTA_MAX+1] __read_mostly = {
[RTA_DST] = { .type = NLA_U32 },
[RTA_SRC] = { .type = NLA_U32 },
[RTA_IIF] = { .type = NLA_U32 },
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 31b6705..a4d4cb8 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2737,18 +2737,24 @@
int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
{
- struct rtattr **rta = arg;
- struct rtmsg *rtm = NLMSG_DATA(nlh);
+ struct rtmsg *rtm;
+ struct nlattr *tb[RTA_MAX+1];
struct rtable *rt = NULL;
- u32 dst = 0;
- u32 src = 0;
- int iif = 0;
- int err = -ENOBUFS;
+ u32 dst, src, iif;
+ int err;
struct sk_buff *skb;
+ err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
+ if (err < 0)
+ goto errout;
+
+ rtm = nlmsg_data(nlh);
+
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
- if (!skb)
- goto out;
+ if (skb == NULL) {
+ err = -ENOBUFS;
+ goto errout;
+ }
/* Reserve room for dummy headers, this skb can pass
through good chunk of routing engine.
@@ -2759,61 +2765,61 @@
skb->nh.iph->protocol = IPPROTO_ICMP;
skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
- if (rta[RTA_SRC - 1])
- memcpy(&src, RTA_DATA(rta[RTA_SRC - 1]), 4);
- if (rta[RTA_DST - 1])
- memcpy(&dst, RTA_DATA(rta[RTA_DST - 1]), 4);
- if (rta[RTA_IIF - 1])
- memcpy(&iif, RTA_DATA(rta[RTA_IIF - 1]), sizeof(int));
+ src = tb[RTA_SRC] ? nla_get_u32(tb[RTA_SRC]) : 0;
+ dst = tb[RTA_DST] ? nla_get_u32(tb[RTA_DST]) : 0;
+ iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
if (iif) {
- struct net_device *dev = __dev_get_by_index(iif);
- err = -ENODEV;
- if (!dev)
- goto out_free;
+ struct net_device *dev;
+
+ dev = __dev_get_by_index(iif);
+ if (dev == NULL) {
+ err = -ENODEV;
+ goto errout_free;
+ }
+
skb->protocol = htons(ETH_P_IP);
skb->dev = dev;
local_bh_disable();
err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
local_bh_enable();
- rt = (struct rtable*)skb->dst;
- if (!err && rt->u.dst.error)
+
+ rt = (struct rtable*) skb->dst;
+ if (err == 0 && rt->u.dst.error)
err = -rt->u.dst.error;
} else {
- struct flowi fl = { .nl_u = { .ip4_u = { .daddr = dst,
- .saddr = src,
- .tos = rtm->rtm_tos } } };
- int oif = 0;
- if (rta[RTA_OIF - 1])
- memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
- fl.oif = oif;
+ struct flowi fl = {
+ .nl_u = {
+ .ip4_u = {
+ .daddr = dst,
+ .saddr = src,
+ .tos = rtm->rtm_tos,
+ },
+ },
+ .oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0,
+ };
err = ip_route_output_key(&rt, &fl);
}
+
if (err)
- goto out_free;
+ goto errout_free;
skb->dst = &rt->u.dst;
if (rtm->rtm_flags & RTM_F_NOTIFY)
rt->rt_flags |= RTCF_NOTIFY;
- NETLINK_CB(skb).dst_pid = NETLINK_CB(in_skb).pid;
-
err = rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
RTM_NEWROUTE, 0, 0);
- if (!err)
- goto out_free;
- if (err < 0) {
- err = -EMSGSIZE;
- goto out_free;
- }
+ if (err <= 0)
+ goto errout_free;
err = rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
-out:
+errout:
return err;
-out_free:
+errout_free:
kfree_skb(skb);
- goto out;
+ goto errout;
}
int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)