diff options
Diffstat (limited to 'net/core/rtnetlink.c')
-rw-r--r-- | net/core/rtnetlink.c | 382 |
1 files changed, 303 insertions, 79 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 24431e578310..0958c7be2c22 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -59,7 +59,7 @@ #include <net/rtnetlink.h> #include <net/net_namespace.h> -#define RTNL_MAX_TYPE 48 +#define RTNL_MAX_TYPE 49 #define RTNL_SLAVE_MAX_TYPE 36 struct rtnl_link { @@ -130,6 +130,12 @@ int rtnl_is_locked(void) } EXPORT_SYMBOL(rtnl_is_locked); +bool refcount_dec_and_rtnl_lock(refcount_t *r) +{ + return refcount_dec_and_mutex_lock(r, &rtnl_mutex); +} +EXPORT_SYMBOL(refcount_dec_and_rtnl_lock); + #ifdef CONFIG_PROVE_LOCKING bool lockdep_rtnl_is_held(void) { @@ -324,6 +330,10 @@ void rtnl_unregister_all(int protocol) rtnl_lock(); tab = rtnl_msg_handlers[protocol]; + if (!tab) { + rtnl_unlock(); + return; + } RCU_INIT_POINTER(rtnl_msg_handlers[protocol], NULL); for (msgindex = 0; msgindex < RTM_NR_MSGTYPES; msgindex++) { link = tab[msgindex]; @@ -1012,7 +1022,7 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev, + nla_total_size(4) /* IFLA_NEW_NETNSID */ + nla_total_size(4) /* IFLA_NEW_IFINDEX */ + nla_total_size(1) /* IFLA_PROTO_DOWN */ - + nla_total_size(4) /* IFLA_IF_NETNSID */ + + nla_total_size(4) /* IFLA_TARGET_NETNSID */ + nla_total_size(4) /* IFLA_CARRIER_UP_COUNT */ + nla_total_size(4) /* IFLA_CARRIER_DOWN_COUNT */ + nla_total_size(4) /* IFLA_MIN_MTU */ @@ -1594,7 +1604,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, ifm->ifi_flags = dev_get_flags(dev); ifm->ifi_change = change; - if (tgt_netnsid >= 0 && nla_put_s32(skb, IFLA_IF_NETNSID, tgt_netnsid)) + if (tgt_netnsid >= 0 && nla_put_s32(skb, IFLA_TARGET_NETNSID, tgt_netnsid)) goto nla_put_failure; if (nla_put_string(skb, IFLA_IFNAME, dev->name) || @@ -1733,7 +1743,7 @@ static const struct nla_policy ifla_policy[IFLA_MAX+1] = { [IFLA_XDP] = { .type = NLA_NESTED }, [IFLA_EVENT] = { .type = NLA_U32 }, [IFLA_GROUP] = { .type = NLA_U32 }, - [IFLA_IF_NETNSID] = { .type = NLA_S32 }, + [IFLA_TARGET_NETNSID] = { .type = NLA_S32 }, [IFLA_CARRIER_UP_COUNT] = { .type = NLA_U32 }, [IFLA_CARRIER_DOWN_COUNT] = { .type = NLA_U32 }, [IFLA_MIN_MTU] = { .type = NLA_U32 }, @@ -1841,7 +1851,15 @@ static bool link_dump_filtered(struct net_device *dev, return false; } -static struct net *get_target_net(struct sock *sk, int netnsid) +/** + * rtnl_get_net_ns_capable - Get netns if sufficiently privileged. + * @sk: netlink socket + * @netnsid: network namespace identifier + * + * Returns the network namespace identified by netnsid on success or an error + * pointer on failure. + */ +struct net *rtnl_get_net_ns_capable(struct sock *sk, int netnsid) { struct net *net; @@ -1858,9 +1876,54 @@ static struct net *get_target_net(struct sock *sk, int netnsid) } return net; } +EXPORT_SYMBOL_GPL(rtnl_get_net_ns_capable); + +static int rtnl_valid_dump_ifinfo_req(const struct nlmsghdr *nlh, + bool strict_check, struct nlattr **tb, + struct netlink_ext_ack *extack) +{ + int hdrlen; + + if (strict_check) { + struct ifinfomsg *ifm; + + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) { + NL_SET_ERR_MSG(extack, "Invalid header for link dump"); + return -EINVAL; + } + + ifm = nlmsg_data(nlh); + if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags || + ifm->ifi_change) { + NL_SET_ERR_MSG(extack, "Invalid values in header for link dump request"); + return -EINVAL; + } + if (ifm->ifi_index) { + NL_SET_ERR_MSG(extack, "Filter by device index not supported for link dumps"); + return -EINVAL; + } + + return nlmsg_parse_strict(nlh, sizeof(*ifm), tb, IFLA_MAX, + ifla_policy, extack); + } + + /* A hack to preserve kernel<->userspace interface. + * The correct header is ifinfomsg. It is consistent with rtnl_getlink. + * However, before Linux v3.9 the code here assumed rtgenmsg and that's + * what iproute2 < v3.9.0 used. + * We can detect the old iproute2. Even including the IFLA_EXT_MASK + * attribute, its netlink message is shorter than struct ifinfomsg. + */ + hdrlen = nlmsg_len(nlh) < sizeof(struct ifinfomsg) ? + sizeof(struct rtgenmsg) : sizeof(struct ifinfomsg); + + return nlmsg_parse(nlh, hdrlen, tb, IFLA_MAX, ifla_policy, extack); +} static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) { + struct netlink_ext_ack *extack = cb->extack; + const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); struct net *tgt_net = net; int h, s_h; @@ -1873,46 +1936,54 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) unsigned int flags = NLM_F_MULTI; int master_idx = 0; int netnsid = -1; - int err; - int hdrlen; + int err, i; s_h = cb->args[0]; s_idx = cb->args[1]; - /* A hack to preserve kernel<->userspace interface. - * The correct header is ifinfomsg. It is consistent with rtnl_getlink. - * However, before Linux v3.9 the code here assumed rtgenmsg and that's - * what iproute2 < v3.9.0 used. - * We can detect the old iproute2. Even including the IFLA_EXT_MASK - * attribute, its netlink message is shorter than struct ifinfomsg. - */ - hdrlen = nlmsg_len(cb->nlh) < sizeof(struct ifinfomsg) ? - sizeof(struct rtgenmsg) : sizeof(struct ifinfomsg); + err = rtnl_valid_dump_ifinfo_req(nlh, cb->strict_check, tb, extack); + if (err < 0) { + if (cb->strict_check) + return err; + + goto walk_entries; + } + + for (i = 0; i <= IFLA_MAX; ++i) { + if (!tb[i]) + continue; - if (nlmsg_parse(cb->nlh, hdrlen, tb, IFLA_MAX, - ifla_policy, NULL) >= 0) { - if (tb[IFLA_IF_NETNSID]) { - netnsid = nla_get_s32(tb[IFLA_IF_NETNSID]); - tgt_net = get_target_net(skb->sk, netnsid); + /* new attributes should only be added with strict checking */ + switch (i) { + case IFLA_TARGET_NETNSID: + netnsid = nla_get_s32(tb[i]); + tgt_net = rtnl_get_net_ns_capable(skb->sk, netnsid); if (IS_ERR(tgt_net)) { - tgt_net = net; - netnsid = -1; + NL_SET_ERR_MSG(extack, "Invalid target network namespace id"); + return PTR_ERR(tgt_net); + } + break; + case IFLA_EXT_MASK: + ext_filter_mask = nla_get_u32(tb[i]); + break; + case IFLA_MASTER: + master_idx = nla_get_u32(tb[i]); + break; + case IFLA_LINKINFO: + kind_ops = linkinfo_to_kind_ops(tb[i]); + break; + default: + if (cb->strict_check) { + NL_SET_ERR_MSG(extack, "Unsupported attribute in link dump request"); + return -EINVAL; } } - - if (tb[IFLA_EXT_MASK]) - ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]); - - if (tb[IFLA_MASTER]) - master_idx = nla_get_u32(tb[IFLA_MASTER]); - - if (tb[IFLA_LINKINFO]) - kind_ops = linkinfo_to_kind_ops(tb[IFLA_LINKINFO]); - - if (master_idx || kind_ops) - flags |= NLM_F_DUMP_FILTERED; } + if (master_idx || kind_ops) + flags |= NLM_F_DUMP_FILTERED; + +walk_entries: for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { idx = 0; head = &tgt_net->dev_index_head[h]; @@ -1924,8 +1995,7 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) err = rtnl_fill_ifinfo(skb, dev, net, RTM_NEWLINK, NETLINK_CB(cb->skb).portid, - cb->nlh->nlmsg_seq, 0, - flags, + nlh->nlmsg_seq, 0, flags, ext_filter_mask, 0, NULL, 0, netnsid); @@ -1980,7 +2050,7 @@ EXPORT_SYMBOL(rtnl_link_get_net); * * 1. IFLA_NET_NS_PID * 2. IFLA_NET_NS_FD - * 3. IFLA_IF_NETNSID + * 3. IFLA_TARGET_NETNSID */ static struct net *rtnl_link_get_net_by_nlattr(struct net *src_net, struct nlattr *tb[]) @@ -1990,10 +2060,10 @@ static struct net *rtnl_link_get_net_by_nlattr(struct net *src_net, if (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD]) return rtnl_link_get_net(src_net, tb); - if (!tb[IFLA_IF_NETNSID]) + if (!tb[IFLA_TARGET_NETNSID]) return get_net(src_net); - net = get_net_ns_by_id(src_net, nla_get_u32(tb[IFLA_IF_NETNSID])); + net = get_net_ns_by_id(src_net, nla_get_u32(tb[IFLA_TARGET_NETNSID])); if (!net) return ERR_PTR(-EINVAL); @@ -2034,13 +2104,13 @@ static int rtnl_ensure_unique_netns(struct nlattr *tb[], return -EOPNOTSUPP; } - if (tb[IFLA_IF_NETNSID] && (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD])) + if (tb[IFLA_TARGET_NETNSID] && (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD])) goto invalid_attr; - if (tb[IFLA_NET_NS_PID] && (tb[IFLA_IF_NETNSID] || tb[IFLA_NET_NS_FD])) + if (tb[IFLA_NET_NS_PID] && (tb[IFLA_TARGET_NETNSID] || tb[IFLA_NET_NS_FD])) goto invalid_attr; - if (tb[IFLA_NET_NS_FD] && (tb[IFLA_IF_NETNSID] || tb[IFLA_NET_NS_PID])) + if (tb[IFLA_NET_NS_FD] && (tb[IFLA_TARGET_NETNSID] || tb[IFLA_NET_NS_PID])) goto invalid_attr; return 0; @@ -2316,7 +2386,7 @@ static int do_setlink(const struct sk_buff *skb, if (err < 0) return err; - if (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD] || tb[IFLA_IF_NETNSID]) { + if (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD] || tb[IFLA_TARGET_NETNSID]) { struct net *net = rtnl_link_get_net_capable(skb, dev_net(dev), tb, CAP_NET_ADMIN); if (IS_ERR(net)) { @@ -2759,9 +2829,9 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, if (tb[IFLA_IFNAME]) nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ); - if (tb[IFLA_IF_NETNSID]) { - netnsid = nla_get_s32(tb[IFLA_IF_NETNSID]); - tgt_net = get_target_net(NETLINK_CB(skb).sk, netnsid); + if (tb[IFLA_TARGET_NETNSID]) { + netnsid = nla_get_s32(tb[IFLA_TARGET_NETNSID]); + tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(skb).sk, netnsid); if (IS_ERR(tgt_net)) return PTR_ERR(tgt_net); } @@ -2806,7 +2876,7 @@ int rtnl_configure_link(struct net_device *dev, const struct ifinfomsg *ifm) } if (dev->rtnl_link_state == RTNL_LINK_INITIALIZED) { - __dev_notify_flags(dev, old_flags, 0U); + __dev_notify_flags(dev, old_flags, (old_flags ^ dev->flags)); } else { dev->rtnl_link_state = RTNL_LINK_INITIALIZED; __dev_notify_flags(dev, old_flags, ~0U); @@ -2833,6 +2903,12 @@ struct net_device *rtnl_create_link(struct net *net, else if (ops->get_num_rx_queues) num_rx_queues = ops->get_num_rx_queues(); + if (num_tx_queues < 1 || num_tx_queues > 4096) + return ERR_PTR(-EINVAL); + + if (num_rx_queues < 1 || num_rx_queues > 4096) + return ERR_PTR(-EINVAL); + dev = alloc_netdev_mqs(ops->priv_size, ifname, name_assign_type, ops->setup, num_tx_queues, num_rx_queues); if (!dev) @@ -3169,9 +3245,9 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh, if (err < 0) return err; - if (tb[IFLA_IF_NETNSID]) { - netnsid = nla_get_s32(tb[IFLA_IF_NETNSID]); - tgt_net = get_target_net(NETLINK_CB(skb).sk, netnsid); + if (tb[IFLA_TARGET_NETNSID]) { + netnsid = nla_get_s32(tb[IFLA_TARGET_NETNSID]); + tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(skb).sk, netnsid); if (IS_ERR(tgt_net)) return PTR_ERR(tgt_net); } @@ -3256,13 +3332,13 @@ static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb) { int idx; int s_idx = cb->family; + int type = cb->nlh->nlmsg_type - RTM_BASE; if (s_idx == 0) s_idx = 1; for (idx = 1; idx <= RTNL_FAMILY_MAX; idx++) { struct rtnl_link **tab; - int type = cb->nlh->nlmsg_type-RTM_BASE; struct rtnl_link *link; rtnl_dumpit_func dumpit; @@ -3723,14 +3799,100 @@ out: } EXPORT_SYMBOL(ndo_dflt_fdb_dump); +static int valid_fdb_dump_strict(const struct nlmsghdr *nlh, + int *br_idx, int *brport_idx, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb[NDA_MAX + 1]; + struct ndmsg *ndm; + int err, i; + + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) { + NL_SET_ERR_MSG(extack, "Invalid header for fdb dump request"); + return -EINVAL; + } + + ndm = nlmsg_data(nlh); + if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_state || + ndm->ndm_flags || ndm->ndm_type) { + NL_SET_ERR_MSG(extack, "Invalid values in header for fbd dump request"); + return -EINVAL; + } + + err = nlmsg_parse_strict(nlh, sizeof(struct ndmsg), tb, NDA_MAX, + NULL, extack); + if (err < 0) + return err; + + *brport_idx = ndm->ndm_ifindex; + for (i = 0; i <= NDA_MAX; ++i) { + if (!tb[i]) + continue; + + switch (i) { + case NDA_IFINDEX: + if (nla_len(tb[i]) != sizeof(u32)) { + NL_SET_ERR_MSG(extack, "Invalid IFINDEX attribute in fdb dump request"); + return -EINVAL; + } + *brport_idx = nla_get_u32(tb[NDA_IFINDEX]); + break; + case NDA_MASTER: + if (nla_len(tb[i]) != sizeof(u32)) { + NL_SET_ERR_MSG(extack, "Invalid MASTER attribute in fdb dump request"); + return -EINVAL; + } + *br_idx = nla_get_u32(tb[NDA_MASTER]); + break; + default: + NL_SET_ERR_MSG(extack, "Unsupported attribute in fdb dump request"); + return -EINVAL; + } + } + + return 0; +} + +static int valid_fdb_dump_legacy(const struct nlmsghdr *nlh, + int *br_idx, int *brport_idx, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb[IFLA_MAX+1]; + int err; + + /* A hack to preserve kernel<->userspace interface. + * Before Linux v4.12 this code accepted ndmsg since iproute2 v3.3.0. + * However, ndmsg is shorter than ifinfomsg thus nlmsg_parse() bails. + * So, check for ndmsg with an optional u32 attribute (not used here). + * Fortunately these sizes don't conflict with the size of ifinfomsg + * with an optional attribute. + */ + if (nlmsg_len(nlh) != sizeof(struct ndmsg) && + (nlmsg_len(nlh) != sizeof(struct ndmsg) + + nla_attr_size(sizeof(u32)))) { + struct ifinfomsg *ifm; + + err = nlmsg_parse(nlh, sizeof(struct ifinfomsg), tb, IFLA_MAX, + ifla_policy, extack); + if (err < 0) { + return -EINVAL; + } else if (err == 0) { + if (tb[IFLA_MASTER]) + *br_idx = nla_get_u32(tb[IFLA_MASTER]); + } + + ifm = nlmsg_data(nlh); + *brport_idx = ifm->ifi_index; + } + return 0; +} + static int rtnl_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb) { struct net_device *dev; - struct nlattr *tb[IFLA_MAX+1]; struct net_device *br_dev = NULL; const struct net_device_ops *ops = NULL; const struct net_device_ops *cops = NULL; - struct ifinfomsg *ifm = nlmsg_data(cb->nlh); struct net *net = sock_net(skb->sk); struct hlist_head *head; int brport_idx = 0; @@ -3740,16 +3902,14 @@ static int rtnl_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb) int err = 0; int fidx = 0; - err = nlmsg_parse(cb->nlh, sizeof(struct ifinfomsg), tb, - IFLA_MAX, ifla_policy, NULL); - if (err < 0) { - return -EINVAL; - } else if (err == 0) { - if (tb[IFLA_MASTER]) - br_idx = nla_get_u32(tb[IFLA_MASTER]); - } - - brport_idx = ifm->ifi_index; + if (cb->strict_check) + err = valid_fdb_dump_strict(cb->nlh, &br_idx, &brport_idx, + cb->extack); + else + err = valid_fdb_dump_legacy(cb->nlh, &br_idx, &brport_idx, + cb->extack); + if (err < 0) + return err; if (br_idx) { br_dev = __dev_get_by_index(net, br_idx); @@ -3934,28 +4094,72 @@ nla_put_failure: } EXPORT_SYMBOL_GPL(ndo_dflt_bridge_getlink); +static int valid_bridge_getlink_req(const struct nlmsghdr *nlh, + bool strict_check, u32 *filter_mask, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb[IFLA_MAX+1]; + int err, i; + + if (strict_check) { + struct ifinfomsg *ifm; + + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) { + NL_SET_ERR_MSG(extack, "Invalid header for bridge link dump"); + return -EINVAL; + } + + ifm = nlmsg_data(nlh); + if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags || + ifm->ifi_change || ifm->ifi_index) { + NL_SET_ERR_MSG(extack, "Invalid values in header for bridge link dump request"); + return -EINVAL; + } + + err = nlmsg_parse_strict(nlh, sizeof(struct ifinfomsg), tb, + IFLA_MAX, ifla_policy, extack); + } else { + err = nlmsg_parse(nlh, sizeof(struct ifinfomsg), tb, + IFLA_MAX, ifla_policy, extack); + } + if (err < 0) + return err; + + /* new attributes should only be added with strict checking */ + for (i = 0; i <= IFLA_MAX; ++i) { + if (!tb[i]) + continue; + + switch (i) { + case IFLA_EXT_MASK: + *filter_mask = nla_get_u32(tb[i]); + break; + default: + if (strict_check) { + NL_SET_ERR_MSG(extack, "Unsupported attribute in bridge link dump request"); + return -EINVAL; + } + } + } + + return 0; +} + static int rtnl_bridge_getlink(struct sk_buff *skb, struct netlink_callback *cb) { + const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); struct net_device *dev; int idx = 0; u32 portid = NETLINK_CB(cb->skb).portid; - u32 seq = cb->nlh->nlmsg_seq; + u32 seq = nlh->nlmsg_seq; u32 filter_mask = 0; int err; - if (nlmsg_len(cb->nlh) > sizeof(struct ifinfomsg)) { - struct nlattr *extfilt; - - extfilt = nlmsg_find_attr(cb->nlh, sizeof(struct ifinfomsg), - IFLA_EXT_MASK); - if (extfilt) { - if (nla_len(extfilt) < sizeof(filter_mask)) - return -EINVAL; - - filter_mask = nla_get_u32(extfilt); - } - } + err = valid_bridge_getlink_req(nlh, cb->strict_check, &filter_mask, + cb->extack); + if (err < 0 && cb->strict_check) + return err; rcu_read_lock(); for_each_netdev_rcu(net, dev) { @@ -4549,6 +4753,7 @@ static int rtnl_stats_get(struct sk_buff *skb, struct nlmsghdr *nlh, static int rtnl_stats_dump(struct sk_buff *skb, struct netlink_callback *cb) { + struct netlink_ext_ack *extack = cb->extack; int h, s_h, err, s_idx, s_idxattr, s_prividx; struct net *net = sock_net(skb->sk); unsigned int flags = NLM_F_MULTI; @@ -4565,13 +4770,32 @@ static int rtnl_stats_dump(struct sk_buff *skb, struct netlink_callback *cb) cb->seq = net->dev_base_seq; - if (nlmsg_len(cb->nlh) < sizeof(*ifsm)) + if (nlmsg_len(cb->nlh) < sizeof(*ifsm)) { + NL_SET_ERR_MSG(extack, "Invalid header for stats dump"); return -EINVAL; + } ifsm = nlmsg_data(cb->nlh); + + /* only requests using strict checks can pass data to influence + * the dump. The legacy exception is filter_mask. + */ + if (cb->strict_check) { + if (ifsm->pad1 || ifsm->pad2 || ifsm->ifindex) { + NL_SET_ERR_MSG(extack, "Invalid values in header for stats dump request"); + return -EINVAL; + } + if (nlmsg_attrlen(cb->nlh, sizeof(*ifsm))) { + NL_SET_ERR_MSG(extack, "Invalid attributes after stats header"); + return -EINVAL; + } + } + filter_mask = ifsm->filter_mask; - if (!filter_mask) + if (!filter_mask) { + NL_SET_ERR_MSG(extack, "Filter mask must be set for stats dump"); return -EINVAL; + } for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { idx = 0; |