From 3c5ab3f395d66a9e4e937fcfdf6ebc63894f028b Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Sat, 29 Apr 2017 20:33:09 +0300 Subject: ipvs: SNAT packet replies only for NATed connections We do not check if packet from real server is for NAT connection before performing SNAT. This causes problems for setups that use DR/TUN and allow local clients to access the real server directly, for example: - local client in director creates IPVS-DR/TUN connection CIP->VIP and the request packets are routed to RIP. Talks are finished but IPVS connection is not expired yet. - second local client creates non-IPVS connection CIP->RIP with same reply tuple RIP->CIP and when replies are received on LOCAL_IN we wrongly assign them for the first client connection because RIP->CIP matches the reply direction. As result, IPVS SNATs replies for non-IPVS connections. The problem is more visible to local UDP clients but in rare cases it can happen also for TCP or remote clients when the real server sends the reply traffic via the director. So, better to be more precise for the reply traffic. As replies are not expected for DR/TUN connections, better to not touch them. Reported-by: Nick Moriarty Tested-by: Nick Moriarty Signed-off-by: Julian Anastasov Signed-off-by: Simon Horman --- net/netfilter/ipvs/ip_vs_core.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'net') diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c index d2d7bdf1d510..ad99c1ceea6f 100644 --- a/net/netfilter/ipvs/ip_vs_core.c +++ b/net/netfilter/ipvs/ip_vs_core.c @@ -849,10 +849,8 @@ static int handle_response_icmp(int af, struct sk_buff *skb, { unsigned int verdict = NF_DROP; - if (IP_VS_FWD_METHOD(cp) != 0) { - pr_err("shouldn't reach here, because the box is on the " - "half connection in the tun/dr module.\n"); - } + if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ) + goto ignore_cp; /* Ensure the checksum is correct */ if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) { @@ -886,6 +884,8 @@ static int handle_response_icmp(int af, struct sk_buff *skb, ip_vs_notrack(skb); else ip_vs_update_conntrack(skb, cp, 0); + +ignore_cp: verdict = NF_ACCEPT; out: @@ -1385,8 +1385,11 @@ ip_vs_out(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, in */ cp = pp->conn_out_get(ipvs, af, skb, &iph); - if (likely(cp)) + if (likely(cp)) { + if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ) + goto ignore_cp; return handle_response(af, skb, pd, cp, &iph, hooknum); + } /* Check for real-server-started requests */ if (atomic_read(&ipvs->conn_out_counter)) { @@ -1444,9 +1447,15 @@ ip_vs_out(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, in } } } + +out: IP_VS_DBG_PKT(12, af, pp, skb, iph.off, "ip_vs_out: packet continues traversal as normal"); return NF_ACCEPT; + +ignore_cp: + __ip_vs_conn_put(cp); + goto out; } /* -- cgit From a2b7cbdd2559aff06cebc28a7150f81c307a90d3 Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Wed, 19 Apr 2017 11:39:20 -0700 Subject: netfilter: ctnetlink: Make some parameters integer to avoid enum mismatch Not all parameters passed to ctnetlink_parse_tuple() and ctnetlink_exp_dump_tuple() match the enum type in the signatures of these functions. Since this is intended change the argument type of to be an unsigned integer value. Signed-off-by: Matthias Kaehlcke Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index dcf561b5c97a..fa752626029e 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1007,9 +1007,8 @@ static const struct nla_policy tuple_nla_policy[CTA_TUPLE_MAX+1] = { static int ctnetlink_parse_tuple(const struct nlattr * const cda[], - struct nf_conntrack_tuple *tuple, - enum ctattr_type type, u_int8_t l3num, - struct nf_conntrack_zone *zone) + struct nf_conntrack_tuple *tuple, u32 type, + u_int8_t l3num, struct nf_conntrack_zone *zone) { struct nlattr *tb[CTA_TUPLE_MAX+1]; int err; @@ -2447,7 +2446,7 @@ static struct nfnl_ct_hook ctnetlink_glue_hook = { static int ctnetlink_exp_dump_tuple(struct sk_buff *skb, const struct nf_conntrack_tuple *tuple, - enum ctattr_expect type) + u32 type) { struct nlattr *nest_parms; -- cgit From d110a3942aca78d14929bc648aeb83ee0b245a61 Mon Sep 17 00:00:00 2001 From: Liping Zhang Date: Sat, 6 May 2017 20:28:02 +0800 Subject: netfilter: don't setup nat info for confirmed ct We cannot setup nat info if the ct has been confirmed already, else, different cpu may race to handle the same ct. In extreme situation, we may hit the "BUG_ON(nf_nat_initialized(ct, maniptype))" in the nf_nat_setup_info. Also running the following commands will easily hit NF_CT_ASSERT in nf_conntrack_alter_reply: # nft flush ruleset # ping -c 2 -W 1 1.1.1.111 & # nft add table t # nft add chain t c {type nat hook postrouting priority 0 \;} # nft add rule t c snat to 4.5.6.7 WARNING: CPU: 1 PID: 10065 at net/netfilter/nf_conntrack_core.c:1472 nf_conntrack_alter_reply+0x9a/0x1a0 [nf_conntrack] [...] Call Trace: nf_nat_setup_info+0xad/0x840 [nf_nat] ? deactivate_slab+0x65d/0x6c0 nft_nat_eval+0xcd/0x100 [nft_nat] nft_do_chain+0xff/0x5d0 [nf_tables] ? mark_held_locks+0x6f/0xa0 ? __local_bh_enable_ip+0x70/0xa0 ? trace_hardirqs_on_caller+0x11f/0x190 ? ipt_do_table+0x310/0x610 ? trace_hardirqs_on+0xd/0x10 ? __local_bh_enable_ip+0x70/0xa0 ? ipt_do_table+0x32b/0x610 ? __lock_acquire+0x2ac/0x1580 ? ipt_do_table+0x32b/0x610 nft_nat_do_chain+0x65/0x80 [nft_chain_nat_ipv4] nf_nat_ipv4_fn+0x1ae/0x240 [nf_nat_ipv4] nf_nat_ipv4_out+0x4a/0xf0 [nf_nat_ipv4] nft_nat_ipv4_out+0x15/0x20 [nft_chain_nat_ipv4] nf_hook_slow+0x2c/0xf0 ip_output+0x154/0x270 So for the confirmed ct, just ignore it and return NF_ACCEPT. Fixes: 9a08ecfe74d7 ("netfilter: don't attach a nat extension by default") Signed-off-by: Liping Zhang Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_nat_core.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net') diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index b48d6b5aae8a..ef0be325a0c6 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -409,6 +409,10 @@ nf_nat_setup_info(struct nf_conn *ct, { struct nf_conntrack_tuple curr_tuple, new_tuple; + /* Can't setup nat info for confirmed ct. */ + if (nf_ct_is_confirmed(ct)) + return NF_ACCEPT; + NF_CT_ASSERT(maniptype == NF_NAT_MANIP_SRC || maniptype == NF_NAT_MANIP_DST); BUG_ON(nf_nat_initialized(ct, maniptype)); -- cgit From d91fc59cd77c719f33eda65c194ad8f95a055190 Mon Sep 17 00:00:00 2001 From: Liping Zhang Date: Sun, 7 May 2017 22:01:55 +0800 Subject: netfilter: introduce nf_conntrack_helper_put helper function And convert module_put invocation to nf_conntrack_helper_put, this is prepared for the followup patch, which will add a refcnt for cthelper, so we can reject the deleting request when cthelper is in use. Signed-off-by: Liping Zhang Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_helper.c | 6 ++++++ net/netfilter/nft_ct.c | 4 ++-- net/netfilter/xt_CT.c | 6 +++--- net/openvswitch/conntrack.c | 4 ++-- 4 files changed, 13 insertions(+), 7 deletions(-) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c index 3a60efa7799b..e17006b6e434 100644 --- a/net/netfilter/nf_conntrack_helper.c +++ b/net/netfilter/nf_conntrack_helper.c @@ -181,6 +181,12 @@ nf_conntrack_helper_try_module_get(const char *name, u16 l3num, u8 protonum) } EXPORT_SYMBOL_GPL(nf_conntrack_helper_try_module_get); +void nf_conntrack_helper_put(struct nf_conntrack_helper *helper) +{ + module_put(helper->me); +} +EXPORT_SYMBOL_GPL(nf_conntrack_helper_put); + struct nf_conn_help * nf_ct_helper_ext_add(struct nf_conn *ct, struct nf_conntrack_helper *helper, gfp_t gfp) diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index a34ceb38fc55..1678e9e75e8e 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -826,9 +826,9 @@ static void nft_ct_helper_obj_destroy(struct nft_object *obj) struct nft_ct_helper_obj *priv = nft_obj_data(obj); if (priv->helper4) - module_put(priv->helper4->me); + nf_conntrack_helper_put(priv->helper4); if (priv->helper6) - module_put(priv->helper6->me); + nf_conntrack_helper_put(priv->helper6); } static void nft_ct_helper_obj_eval(struct nft_object *obj, diff --git a/net/netfilter/xt_CT.c b/net/netfilter/xt_CT.c index bb7ad82dcd56..623ef37de886 100644 --- a/net/netfilter/xt_CT.c +++ b/net/netfilter/xt_CT.c @@ -96,7 +96,7 @@ xt_ct_set_helper(struct nf_conn *ct, const char *helper_name, help = nf_ct_helper_ext_add(ct, helper, GFP_KERNEL); if (help == NULL) { - module_put(helper->me); + nf_conntrack_helper_put(helper); return -ENOMEM; } @@ -263,7 +263,7 @@ out: err4: help = nfct_help(ct); if (help) - module_put(help->helper->me); + nf_conntrack_helper_put(help->helper); err3: nf_ct_tmpl_free(ct); err2: @@ -346,7 +346,7 @@ static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par, if (ct) { help = nfct_help(ct); if (help) - module_put(help->helper->me); + nf_conntrack_helper_put(help->helper); nf_ct_netns_put(par->net, par->family); diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c index bf602e33c40a..08679ebb3068 100644 --- a/net/openvswitch/conntrack.c +++ b/net/openvswitch/conntrack.c @@ -1123,7 +1123,7 @@ static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name, help = nf_ct_helper_ext_add(info->ct, helper, GFP_KERNEL); if (!help) { - module_put(helper->me); + nf_conntrack_helper_put(helper); return -ENOMEM; } @@ -1584,7 +1584,7 @@ void ovs_ct_free_action(const struct nlattr *a) static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info) { if (ct_info->helper) - module_put(ct_info->helper->me); + nf_conntrack_helper_put(ct_info->helper); if (ct_info->ct) nf_ct_tmpl_free(ct_info->ct); } -- cgit From 9338d7b4418e9996a7642867d8f6b482a6040ed6 Mon Sep 17 00:00:00 2001 From: Liping Zhang Date: Sun, 7 May 2017 22:01:56 +0800 Subject: netfilter: nfnl_cthelper: reject del request if helper obj is in use We can still delete the ct helper even if it is in use, this will cause a use-after-free error. In more detail, I mean: # nfct helper add ssdp inet udp # iptables -t raw -A OUTPUT -p udp -j CT --helper ssdp # nfct helper delete ssdp //--> oops, succeed! BUG: unable to handle kernel paging request at 000026ca IP: 0x26ca [...] Call Trace: ? ipv4_helper+0x62/0x80 [nf_conntrack_ipv4] nf_hook_slow+0x21/0xb0 ip_output+0xe9/0x100 ? ip_fragment.constprop.54+0xc0/0xc0 ip_local_out+0x33/0x40 ip_send_skb+0x16/0x80 udp_send_skb+0x84/0x240 udp_sendmsg+0x35d/0xa50 So add reference count to fix this issue, if ct helper is used by others, reject the delete request. Apply this patch: # nfct helper delete ssdp nfct v1.4.3: netlink error: Device or resource busy Signed-off-by: Liping Zhang Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_helper.c | 6 ++++++ net/netfilter/nfnetlink_cthelper.c | 17 +++++++++++------ 2 files changed, 17 insertions(+), 6 deletions(-) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c index e17006b6e434..7f6100ca63be 100644 --- a/net/netfilter/nf_conntrack_helper.c +++ b/net/netfilter/nf_conntrack_helper.c @@ -174,6 +174,10 @@ nf_conntrack_helper_try_module_get(const char *name, u16 l3num, u8 protonum) #endif if (h != NULL && !try_module_get(h->me)) h = NULL; + if (h != NULL && !refcount_inc_not_zero(&h->refcnt)) { + module_put(h->me); + h = NULL; + } rcu_read_unlock(); @@ -183,6 +187,7 @@ EXPORT_SYMBOL_GPL(nf_conntrack_helper_try_module_get); void nf_conntrack_helper_put(struct nf_conntrack_helper *helper) { + refcount_dec(&helper->refcnt); module_put(helper->me); } EXPORT_SYMBOL_GPL(nf_conntrack_helper_put); @@ -423,6 +428,7 @@ int nf_conntrack_helper_register(struct nf_conntrack_helper *me) } } } + refcount_set(&me->refcnt, 1); hlist_add_head_rcu(&me->hnode, &nf_ct_helper_hash[h]); nf_ct_helper_count++; out: diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c index 950bf6eadc65..be678a323598 100644 --- a/net/netfilter/nfnetlink_cthelper.c +++ b/net/netfilter/nfnetlink_cthelper.c @@ -686,6 +686,7 @@ static int nfnl_cthelper_del(struct net *net, struct sock *nfnl, tuple_set = true; } + ret = -ENOENT; list_for_each_entry_safe(nlcth, n, &nfnl_cthelper_list, list) { cur = &nlcth->helper; j++; @@ -699,16 +700,20 @@ static int nfnl_cthelper_del(struct net *net, struct sock *nfnl, tuple.dst.protonum != cur->tuple.dst.protonum)) continue; - found = true; - nf_conntrack_helper_unregister(cur); - kfree(cur->expect_policy); + if (refcount_dec_if_one(&cur->refcnt)) { + found = true; + nf_conntrack_helper_unregister(cur); + kfree(cur->expect_policy); - list_del(&nlcth->list); - kfree(nlcth); + list_del(&nlcth->list); + kfree(nlcth); + } else { + ret = -EBUSY; + } } /* Make sure we return success if we flush and there is no helpers */ - return (found || j == 0) ? 0 : -ENOENT; + return (found || j == 0) ? 0 : ret; } static const struct nla_policy nfnl_cthelper_policy[NFCTH_MAX+1] = { -- cgit From 324318f0248c31be8a08984146e7e4dd7cdd091d Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Tue, 9 May 2017 16:17:37 -0400 Subject: netfilter: xtables: zero padding in data_to_user When looking up an iptables rule, the iptables binary compares the aligned match and target data (XT_ALIGN). In some cases this can exceed the actual data size to include padding bytes. Before commit f77bc5b23fb1 ("iptables: use match, target and data copy_to_user helpers") the malloc()ed bytes were overwritten by the kernel with kzalloced contents, zeroing the padding and making the comparison succeed. After this patch, the kernel copies and clears only data, leaving the padding bytes undefined. Extend the clear operation from data size to aligned data size to include the padding bytes, if any. Padding bytes can be observed in both match and target, and the bug triggered, by issuing a rule with match icmp and target ACCEPT: iptables -t mangle -A INPUT -i lo -p icmp --icmp-type 1 -j ACCEPT iptables -t mangle -D INPUT -i lo -p icmp --icmp-type 1 -j ACCEPT Fixes: f77bc5b23fb1 ("iptables: use match, target and data copy_to_user helpers") Reported-by: Paul Moore Reported-by: Richard Guy Briggs Signed-off-by: Willem de Bruijn Signed-off-by: Pablo Neira Ayuso --- net/bridge/netfilter/ebtables.c | 9 ++++++--- net/netfilter/x_tables.c | 9 ++++++--- 2 files changed, 12 insertions(+), 6 deletions(-) (limited to 'net') diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 9ec0c9f908fa..9c6e619f452b 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1373,7 +1373,8 @@ static inline int ebt_obj_to_user(char __user *um, const char *_name, strlcpy(name, _name, sizeof(name)); if (copy_to_user(um, name, EBT_FUNCTION_MAXNAMELEN) || put_user(datasize, (int __user *)(um + EBT_FUNCTION_MAXNAMELEN)) || - xt_data_to_user(um + entrysize, data, usersize, datasize)) + xt_data_to_user(um + entrysize, data, usersize, datasize, + XT_ALIGN(datasize))) return -EFAULT; return 0; @@ -1658,7 +1659,8 @@ static int compat_match_to_user(struct ebt_entry_match *m, void __user **dstptr, if (match->compat_to_user(cm->data, m->data)) return -EFAULT; } else { - if (xt_data_to_user(cm->data, m->data, match->usersize, msize)) + if (xt_data_to_user(cm->data, m->data, match->usersize, msize, + COMPAT_XT_ALIGN(msize))) return -EFAULT; } @@ -1687,7 +1689,8 @@ static int compat_target_to_user(struct ebt_entry_target *t, if (target->compat_to_user(cm->data, t->data)) return -EFAULT; } else { - if (xt_data_to_user(cm->data, t->data, target->usersize, tsize)) + if (xt_data_to_user(cm->data, t->data, target->usersize, tsize, + COMPAT_XT_ALIGN(tsize))) return -EFAULT; } diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index 8876b7da6884..d17769599c10 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -283,12 +283,13 @@ static int xt_obj_to_user(u16 __user *psize, u16 size, &U->u.user.revision, K->u.kernel.TYPE->revision) int xt_data_to_user(void __user *dst, const void *src, - int usersize, int size) + int usersize, int size, int aligned_size) { usersize = usersize ? : size; if (copy_to_user(dst, src, usersize)) return -EFAULT; - if (usersize != size && clear_user(dst + usersize, size - usersize)) + if (usersize != aligned_size && + clear_user(dst + usersize, aligned_size - usersize)) return -EFAULT; return 0; @@ -298,7 +299,9 @@ EXPORT_SYMBOL_GPL(xt_data_to_user); #define XT_DATA_TO_USER(U, K, TYPE, C_SIZE) \ xt_data_to_user(U->data, K->data, \ K->u.kernel.TYPE->usersize, \ - C_SIZE ? : K->u.kernel.TYPE->TYPE##size) + C_SIZE ? : K->u.kernel.TYPE->TYPE##size, \ + C_SIZE ? COMPAT_XT_ALIGN(C_SIZE) : \ + XT_ALIGN(K->u.kernel.TYPE->TYPE##size)) int xt_match_to_user(const struct xt_entry_match *m, struct xt_entry_match __user *u) -- cgit From 87e94dbc210a720a34be5c1174faee5c84be963e Mon Sep 17 00:00:00 2001 From: Eric Leblond Date: Thu, 11 May 2017 18:56:38 +0200 Subject: netfilter: synproxy: fix conntrackd interaction This patch fixes the creation of connection tracking entry from netlink when synproxy is used. It was missing the addition of the synproxy extension. This was causing kernel crashes when a conntrack entry created by conntrackd was used after the switch of traffic from active node to the passive node. Signed-off-by: Eric Leblond Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index fa752626029e..9799a50bc604 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -45,6 +45,8 @@ #include #include #include +#include +#include #ifdef CONFIG_NF_NAT_NEEDED #include #include @@ -1827,6 +1829,8 @@ ctnetlink_create_conntrack(struct net *net, nf_ct_tstamp_ext_add(ct, GFP_ATOMIC); nf_ct_ecache_ext_add(ct, 0, 0, GFP_ATOMIC); nf_ct_labels_ext_add(ct); + nfct_seqadj_ext_add(ct); + nfct_synproxy_ext_add(ct); /* we must add conntrack extensions before confirmation. */ ct->status |= IPS_CONFIRMED; -- cgit From fa803605eef39372e53d7813002d73a3fcf10c88 Mon Sep 17 00:00:00 2001 From: Liping Zhang Date: Sun, 14 May 2017 21:35:22 +0800 Subject: netfilter: nf_tables: can't assume lock is acquired when dumping set elems When dumping the elements related to a specified set, we may invoke the nf_tables_dump_set with the NFNL_SUBSYS_NFTABLES lock not acquired. So we should use the proper rcu operation to avoid race condition, just like other nft dump operations. Signed-off-by: Liping Zhang Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 78 +++++++++++++++++++++++++++++++------------ net/netfilter/nft_set_hash.c | 2 +- 2 files changed, 57 insertions(+), 23 deletions(-) (limited to 'net') diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 559225029740..5f4a4d48b871 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -3367,35 +3367,50 @@ static int nf_tables_dump_setelem(const struct nft_ctx *ctx, return nf_tables_fill_setelem(args->skb, set, elem); } +struct nft_set_dump_ctx { + const struct nft_set *set; + struct nft_ctx ctx; +}; + static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb) { + struct nft_set_dump_ctx *dump_ctx = cb->data; struct net *net = sock_net(skb->sk); - u8 genmask = nft_genmask_cur(net); + struct nft_af_info *afi; + struct nft_table *table; struct nft_set *set; struct nft_set_dump_args args; - struct nft_ctx ctx; - struct nlattr *nla[NFTA_SET_ELEM_LIST_MAX + 1]; + bool set_found = false; struct nfgenmsg *nfmsg; struct nlmsghdr *nlh; struct nlattr *nest; u32 portid, seq; - int event, err; + int event; - err = nlmsg_parse(cb->nlh, sizeof(struct nfgenmsg), nla, - NFTA_SET_ELEM_LIST_MAX, nft_set_elem_list_policy, - NULL); - if (err < 0) - return err; + rcu_read_lock(); + list_for_each_entry_rcu(afi, &net->nft.af_info, list) { + if (afi != dump_ctx->ctx.afi) + continue; - err = nft_ctx_init_from_elemattr(&ctx, net, cb->skb, cb->nlh, - (void *)nla, genmask); - if (err < 0) - return err; + list_for_each_entry_rcu(table, &afi->tables, list) { + if (table != dump_ctx->ctx.table) + continue; - set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_ELEM_LIST_SET], - genmask); - if (IS_ERR(set)) - return PTR_ERR(set); + list_for_each_entry_rcu(set, &table->sets, list) { + if (set == dump_ctx->set) { + set_found = true; + break; + } + } + break; + } + break; + } + + if (!set_found) { + rcu_read_unlock(); + return -ENOENT; + } event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWSETELEM); portid = NETLINK_CB(cb->skb).portid; @@ -3407,11 +3422,11 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb) goto nla_put_failure; nfmsg = nlmsg_data(nlh); - nfmsg->nfgen_family = ctx.afi->family; + nfmsg->nfgen_family = afi->family; nfmsg->version = NFNETLINK_V0; - nfmsg->res_id = htons(ctx.net->nft.base_seq & 0xffff); + nfmsg->res_id = htons(net->nft.base_seq & 0xffff); - if (nla_put_string(skb, NFTA_SET_ELEM_LIST_TABLE, ctx.table->name)) + if (nla_put_string(skb, NFTA_SET_ELEM_LIST_TABLE, table->name)) goto nla_put_failure; if (nla_put_string(skb, NFTA_SET_ELEM_LIST_SET, set->name)) goto nla_put_failure; @@ -3422,12 +3437,13 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb) args.cb = cb; args.skb = skb; - args.iter.genmask = nft_genmask_cur(ctx.net); + args.iter.genmask = nft_genmask_cur(net); args.iter.skip = cb->args[0]; args.iter.count = 0; args.iter.err = 0; args.iter.fn = nf_tables_dump_setelem; - set->ops->walk(&ctx, set, &args.iter); + set->ops->walk(&dump_ctx->ctx, set, &args.iter); + rcu_read_unlock(); nla_nest_end(skb, nest); nlmsg_end(skb, nlh); @@ -3441,9 +3457,16 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb) return skb->len; nla_put_failure: + rcu_read_unlock(); return -ENOSPC; } +static int nf_tables_dump_set_done(struct netlink_callback *cb) +{ + kfree(cb->data); + return 0; +} + static int nf_tables_getsetelem(struct net *net, struct sock *nlsk, struct sk_buff *skb, const struct nlmsghdr *nlh, const struct nlattr * const nla[]) @@ -3465,7 +3488,18 @@ static int nf_tables_getsetelem(struct net *net, struct sock *nlsk, if (nlh->nlmsg_flags & NLM_F_DUMP) { struct netlink_dump_control c = { .dump = nf_tables_dump_set, + .done = nf_tables_dump_set_done, }; + struct nft_set_dump_ctx *dump_ctx; + + dump_ctx = kmalloc(sizeof(*dump_ctx), GFP_KERNEL); + if (!dump_ctx) + return -ENOMEM; + + dump_ctx->set = set; + dump_ctx->ctx = ctx; + + c.data = dump_ctx; return netlink_dump_start(nlsk, skb, nlh, &c); } return -EOPNOTSUPP; diff --git a/net/netfilter/nft_set_hash.c b/net/netfilter/nft_set_hash.c index 8ec086b6b56b..3d3a6df4ce70 100644 --- a/net/netfilter/nft_set_hash.c +++ b/net/netfilter/nft_set_hash.c @@ -222,7 +222,7 @@ static void nft_hash_walk(const struct nft_ctx *ctx, struct nft_set *set, struct nft_set_elem elem; int err; - err = rhashtable_walk_init(&priv->ht, &hti, GFP_KERNEL); + err = rhashtable_walk_init(&priv->ht, &hti, GFP_ATOMIC); iter->err = err; if (err) return; -- cgit From 71df14b0ce094be46d105b5a3ededd83b8e779a0 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 15 May 2017 11:17:29 +0100 Subject: netfilter: nf_tables: missing sanitization in data from userspace Do not assume userspace always sends us NFT_DATA_VALUE for bitwise and cmp expressions. Although NFT_DATA_VERDICT does not make any sense, it is still possible to handcraft a netlink message using this incorrect data type. Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_bitwise.c | 19 ++++++++++++++----- net/netfilter/nft_cmp.c | 12 ++++++++++-- 2 files changed, 24 insertions(+), 7 deletions(-) (limited to 'net') diff --git a/net/netfilter/nft_bitwise.c b/net/netfilter/nft_bitwise.c index 877d9acd91ef..96bd4f325b0f 100644 --- a/net/netfilter/nft_bitwise.c +++ b/net/netfilter/nft_bitwise.c @@ -83,17 +83,26 @@ static int nft_bitwise_init(const struct nft_ctx *ctx, tb[NFTA_BITWISE_MASK]); if (err < 0) return err; - if (d1.len != priv->len) - return -EINVAL; + if (d1.len != priv->len) { + err = -EINVAL; + goto err1; + } err = nft_data_init(NULL, &priv->xor, sizeof(priv->xor), &d2, tb[NFTA_BITWISE_XOR]); if (err < 0) - return err; - if (d2.len != priv->len) - return -EINVAL; + goto err1; + if (d2.len != priv->len) { + err = -EINVAL; + goto err2; + } return 0; +err2: + nft_data_uninit(&priv->xor, d2.type); +err1: + nft_data_uninit(&priv->mask, d1.type); + return err; } static int nft_bitwise_dump(struct sk_buff *skb, const struct nft_expr *expr) diff --git a/net/netfilter/nft_cmp.c b/net/netfilter/nft_cmp.c index 2b96effeadc1..8c9d0fb19118 100644 --- a/net/netfilter/nft_cmp.c +++ b/net/netfilter/nft_cmp.c @@ -201,10 +201,18 @@ nft_cmp_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[]) if (err < 0) return ERR_PTR(err); + if (desc.type != NFT_DATA_VALUE) { + err = -EINVAL; + goto err1; + } + if (desc.len <= sizeof(u32) && op == NFT_CMP_EQ) return &nft_cmp_fast_ops; - else - return &nft_cmp_ops; + + return &nft_cmp_ops; +err1: + nft_data_uninit(&data, desc.type); + return ERR_PTR(-EINVAL); } struct nft_expr_type nft_cmp_type __read_mostly = { -- cgit From 591054469b3eef34bc097c30fae8ededddf8d796 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 15 May 2017 11:17:34 +0100 Subject: netfilter: nf_tables: revisit chain/object refcounting from elements Andreas reports that the following incremental update using our commit protocol doesn't work. # nft -f incremental-update.nft delete element ip filter client_to_any { 10.180.86.22 : goto CIn_1 } delete chain ip filter CIn_1 ... Error: Could not process rule: Device or resource busy The existing code is not well-integrated into the commit phase protocol, since element deletions do not result in refcount decrement from the preparation phase. This results in bogus EBUSY errors like the one above. Two new functions come with this patch: * nft_set_elem_activate() function is used from the abort path, to restore the set element refcounting on objects that occurred from the preparation phase. * nft_set_elem_deactivate() that is called from nft_del_setelem() to decrement set element refcounting on objects from the preparation phase in the commit protocol. The nft_data_uninit() has been renamed to nft_data_release() since this function does not uninitialize any data store in the data register, instead just releases the references to objects. Moreover, a new function nft_data_hold() has been introduced to be used from nft_set_elem_activate(). Reported-by: Andreas Schultz Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 82 +++++++++++++++++++++++++++++++++++++------ net/netfilter/nft_bitwise.c | 4 +-- net/netfilter/nft_cmp.c | 2 +- net/netfilter/nft_immediate.c | 5 +-- net/netfilter/nft_range.c | 4 +-- 5 files changed, 80 insertions(+), 17 deletions(-) (limited to 'net') diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 5f4a4d48b871..da314be0c048 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -3627,9 +3627,9 @@ void nft_set_elem_destroy(const struct nft_set *set, void *elem, { struct nft_set_ext *ext = nft_set_elem_ext(set, elem); - nft_data_uninit(nft_set_ext_key(ext), NFT_DATA_VALUE); + nft_data_release(nft_set_ext_key(ext), NFT_DATA_VALUE); if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA)) - nft_data_uninit(nft_set_ext_data(ext), set->dtype); + nft_data_release(nft_set_ext_data(ext), set->dtype); if (destroy_expr && nft_set_ext_exists(ext, NFT_SET_EXT_EXPR)) nf_tables_expr_destroy(NULL, nft_set_ext_expr(ext)); if (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF)) @@ -3638,6 +3638,18 @@ void nft_set_elem_destroy(const struct nft_set *set, void *elem, } EXPORT_SYMBOL_GPL(nft_set_elem_destroy); +/* Only called from commit path, nft_set_elem_deactivate() already deals with + * the refcounting from the preparation phase. + */ +static void nf_tables_set_elem_destroy(const struct nft_set *set, void *elem) +{ + struct nft_set_ext *ext = nft_set_elem_ext(set, elem); + + if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPR)) + nf_tables_expr_destroy(NULL, nft_set_ext_expr(ext)); + kfree(elem); +} + static int nft_setelem_parse_flags(const struct nft_set *set, const struct nlattr *attr, u32 *flags) { @@ -3849,9 +3861,9 @@ err4: kfree(elem.priv); err3: if (nla[NFTA_SET_ELEM_DATA] != NULL) - nft_data_uninit(&data, d2.type); + nft_data_release(&data, d2.type); err2: - nft_data_uninit(&elem.key.val, d1.type); + nft_data_release(&elem.key.val, d1.type); err1: return err; } @@ -3896,6 +3908,53 @@ static int nf_tables_newsetelem(struct net *net, struct sock *nlsk, return err; } +/** + * nft_data_hold - hold a nft_data item + * + * @data: struct nft_data to release + * @type: type of data + * + * Hold a nft_data item. NFT_DATA_VALUE types can be silently discarded, + * NFT_DATA_VERDICT bumps the reference to chains in case of NFT_JUMP and + * NFT_GOTO verdicts. This function must be called on active data objects + * from the second phase of the commit protocol. + */ +static void nft_data_hold(const struct nft_data *data, enum nft_data_types type) +{ + if (type == NFT_DATA_VERDICT) { + switch (data->verdict.code) { + case NFT_JUMP: + case NFT_GOTO: + data->verdict.chain->use++; + break; + } + } +} + +static void nft_set_elem_activate(const struct net *net, + const struct nft_set *set, + struct nft_set_elem *elem) +{ + const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv); + + if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA)) + nft_data_hold(nft_set_ext_data(ext), set->dtype); + if (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF)) + (*nft_set_ext_obj(ext))->use++; +} + +static void nft_set_elem_deactivate(const struct net *net, + const struct nft_set *set, + struct nft_set_elem *elem) +{ + const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv); + + if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA)) + nft_data_release(nft_set_ext_data(ext), set->dtype); + if (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF)) + (*nft_set_ext_obj(ext))->use--; +} + static int nft_del_setelem(struct nft_ctx *ctx, struct nft_set *set, const struct nlattr *attr) { @@ -3961,6 +4020,8 @@ static int nft_del_setelem(struct nft_ctx *ctx, struct nft_set *set, kfree(elem.priv); elem.priv = priv; + nft_set_elem_deactivate(ctx->net, set, &elem); + nft_trans_elem(trans) = elem; list_add_tail(&trans->list, &ctx->net->nft.commit_list); return 0; @@ -3970,7 +4031,7 @@ err4: err3: kfree(elem.priv); err2: - nft_data_uninit(&elem.key.val, desc.type); + nft_data_release(&elem.key.val, desc.type); err1: return err; } @@ -4777,8 +4838,8 @@ static void nf_tables_commit_release(struct nft_trans *trans) nft_set_destroy(nft_trans_set(trans)); break; case NFT_MSG_DELSETELEM: - nft_set_elem_destroy(nft_trans_elem_set(trans), - nft_trans_elem(trans).priv, true); + nf_tables_set_elem_destroy(nft_trans_elem_set(trans), + nft_trans_elem(trans).priv); break; case NFT_MSG_DELOBJ: nft_obj_destroy(nft_trans_obj(trans)); @@ -5013,6 +5074,7 @@ static int nf_tables_abort(struct net *net, struct sk_buff *skb) case NFT_MSG_DELSETELEM: te = (struct nft_trans_elem *)trans->data; + nft_set_elem_activate(net, te->set, &te->elem); te->set->ops->activate(net, te->set, &te->elem); te->set->ndeact--; @@ -5498,7 +5560,7 @@ int nft_data_init(const struct nft_ctx *ctx, EXPORT_SYMBOL_GPL(nft_data_init); /** - * nft_data_uninit - release a nft_data item + * nft_data_release - release a nft_data item * * @data: struct nft_data to release * @type: type of data @@ -5506,7 +5568,7 @@ EXPORT_SYMBOL_GPL(nft_data_init); * Release a nft_data item. NFT_DATA_VALUE types can be silently discarded, * all others need to be released by calling this function. */ -void nft_data_uninit(const struct nft_data *data, enum nft_data_types type) +void nft_data_release(const struct nft_data *data, enum nft_data_types type) { if (type < NFT_DATA_VERDICT) return; @@ -5517,7 +5579,7 @@ void nft_data_uninit(const struct nft_data *data, enum nft_data_types type) WARN_ON(1); } } -EXPORT_SYMBOL_GPL(nft_data_uninit); +EXPORT_SYMBOL_GPL(nft_data_release); int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data, enum nft_data_types type, unsigned int len) diff --git a/net/netfilter/nft_bitwise.c b/net/netfilter/nft_bitwise.c index 96bd4f325b0f..fff8073e2a56 100644 --- a/net/netfilter/nft_bitwise.c +++ b/net/netfilter/nft_bitwise.c @@ -99,9 +99,9 @@ static int nft_bitwise_init(const struct nft_ctx *ctx, return 0; err2: - nft_data_uninit(&priv->xor, d2.type); + nft_data_release(&priv->xor, d2.type); err1: - nft_data_uninit(&priv->mask, d1.type); + nft_data_release(&priv->mask, d1.type); return err; } diff --git a/net/netfilter/nft_cmp.c b/net/netfilter/nft_cmp.c index 8c9d0fb19118..c2945eb3397c 100644 --- a/net/netfilter/nft_cmp.c +++ b/net/netfilter/nft_cmp.c @@ -211,7 +211,7 @@ nft_cmp_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[]) return &nft_cmp_ops; err1: - nft_data_uninit(&data, desc.type); + nft_data_release(&data, desc.type); return ERR_PTR(-EINVAL); } diff --git a/net/netfilter/nft_immediate.c b/net/netfilter/nft_immediate.c index 728baf88295a..4717d7796927 100644 --- a/net/netfilter/nft_immediate.c +++ b/net/netfilter/nft_immediate.c @@ -65,7 +65,7 @@ static int nft_immediate_init(const struct nft_ctx *ctx, return 0; err1: - nft_data_uninit(&priv->data, desc.type); + nft_data_release(&priv->data, desc.type); return err; } @@ -73,7 +73,8 @@ static void nft_immediate_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) { const struct nft_immediate_expr *priv = nft_expr_priv(expr); - return nft_data_uninit(&priv->data, nft_dreg_to_type(priv->dreg)); + + return nft_data_release(&priv->data, nft_dreg_to_type(priv->dreg)); } static int nft_immediate_dump(struct sk_buff *skb, const struct nft_expr *expr) diff --git a/net/netfilter/nft_range.c b/net/netfilter/nft_range.c index 9edc74eedc10..cedb96c3619f 100644 --- a/net/netfilter/nft_range.c +++ b/net/netfilter/nft_range.c @@ -102,9 +102,9 @@ static int nft_range_init(const struct nft_ctx *ctx, const struct nft_expr *expr priv->len = desc_from.len; return 0; err2: - nft_data_uninit(&priv->data_to, desc_to.type); + nft_data_release(&priv->data_to, desc_to.type); err1: - nft_data_uninit(&priv->data_from, desc_from.type); + nft_data_release(&priv->data_from, desc_from.type); return err; } -- cgit From c953d63548207a085abcb12a15fefc8a11ffdf0a Mon Sep 17 00:00:00 2001 From: Gao Feng Date: Tue, 16 May 2017 09:30:18 +0800 Subject: ebtables: arpreply: Add the standard target sanity check The info->target comes from userspace and it would be used directly. So we need to add the sanity check to make sure it is a valid standard target, although the ebtables tool has already checked it. Kernel needs to validate anything coming from userspace. If the target is set as an evil value, it would break the ebtables and cause a panic. Because the non-standard target is treated as one offset. Now add one helper function ebt_invalid_target, and we would replace the macro INVALID_TARGET later. Signed-off-by: Gao Feng Signed-off-by: Pablo Neira Ayuso --- net/bridge/netfilter/ebt_arpreply.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net') diff --git a/net/bridge/netfilter/ebt_arpreply.c b/net/bridge/netfilter/ebt_arpreply.c index 5929309beaa1..db85230e49c3 100644 --- a/net/bridge/netfilter/ebt_arpreply.c +++ b/net/bridge/netfilter/ebt_arpreply.c @@ -68,6 +68,9 @@ static int ebt_arpreply_tg_check(const struct xt_tgchk_param *par) if (e->ethproto != htons(ETH_P_ARP) || e->invflags & EBT_IPROTO) return -EINVAL; + if (ebt_invalid_target(info->target)) + return -EINVAL; + return 0; } -- cgit From 751a9c763849f5859cb69ea44b0430d00672f637 Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Wed, 17 May 2017 11:24:47 -0400 Subject: netfilter: xtables: fix build failure from COMPAT_XT_ALIGN outside CONFIG_COMPAT The patch in the Fixes references COMPAT_XT_ALIGN in the definition of XT_DATA_TO_USER, outside an #ifdef CONFIG_COMPAT block. Split XT_DATA_TO_USER into separate compat and non compat variants and define the first inside an CONFIG_COMPAT block. This simplifies both variants by removing branches inside the macro. Fixes: 324318f0248c ("netfilter: xtables: zero padding in data_to_user") Reported-by: Stephen Rothwell Signed-off-by: Willem de Bruijn Signed-off-by: Pablo Neira Ayuso --- net/netfilter/x_tables.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'net') diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index d17769599c10..1770c1d9b37f 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -296,18 +296,17 @@ int xt_data_to_user(void __user *dst, const void *src, } EXPORT_SYMBOL_GPL(xt_data_to_user); -#define XT_DATA_TO_USER(U, K, TYPE, C_SIZE) \ +#define XT_DATA_TO_USER(U, K, TYPE) \ xt_data_to_user(U->data, K->data, \ K->u.kernel.TYPE->usersize, \ - C_SIZE ? : K->u.kernel.TYPE->TYPE##size, \ - C_SIZE ? COMPAT_XT_ALIGN(C_SIZE) : \ - XT_ALIGN(K->u.kernel.TYPE->TYPE##size)) + K->u.kernel.TYPE->TYPE##size, \ + XT_ALIGN(K->u.kernel.TYPE->TYPE##size)) int xt_match_to_user(const struct xt_entry_match *m, struct xt_entry_match __user *u) { return XT_OBJ_TO_USER(u, m, match, 0) || - XT_DATA_TO_USER(u, m, match, 0); + XT_DATA_TO_USER(u, m, match); } EXPORT_SYMBOL_GPL(xt_match_to_user); @@ -315,7 +314,7 @@ int xt_target_to_user(const struct xt_entry_target *t, struct xt_entry_target __user *u) { return XT_OBJ_TO_USER(u, t, target, 0) || - XT_DATA_TO_USER(u, t, target, 0); + XT_DATA_TO_USER(u, t, target); } EXPORT_SYMBOL_GPL(xt_target_to_user); @@ -614,6 +613,12 @@ void xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr, } EXPORT_SYMBOL_GPL(xt_compat_match_from_user); +#define COMPAT_XT_DATA_TO_USER(U, K, TYPE, C_SIZE) \ + xt_data_to_user(U->data, K->data, \ + K->u.kernel.TYPE->usersize, \ + C_SIZE, \ + COMPAT_XT_ALIGN(C_SIZE)) + int xt_compat_match_to_user(const struct xt_entry_match *m, void __user **dstptr, unsigned int *size) { @@ -629,7 +634,7 @@ int xt_compat_match_to_user(const struct xt_entry_match *m, if (match->compat_to_user((void __user *)cm->data, m->data)) return -EFAULT; } else { - if (XT_DATA_TO_USER(cm, m, match, msize - sizeof(*cm))) + if (COMPAT_XT_DATA_TO_USER(cm, m, match, msize - sizeof(*cm))) return -EFAULT; } @@ -975,7 +980,7 @@ int xt_compat_target_to_user(const struct xt_entry_target *t, if (target->compat_to_user((void __user *)ct->data, t->data)) return -EFAULT; } else { - if (XT_DATA_TO_USER(ct, t, target, tsize - sizeof(*ct))) + if (COMPAT_XT_DATA_TO_USER(ct, t, target, tsize - sizeof(*ct))) return -EFAULT; } -- cgit From 499350a5a6e7512d9ed369ed63a4244b6536f4f8 Mon Sep 17 00:00:00 2001 From: Wei Wang Date: Thu, 18 May 2017 11:22:33 -0700 Subject: tcp: initialize rcv_mss to TCP_MIN_MSS instead of 0 When tcp_disconnect() is called, inet_csk_delack_init() sets icsk->icsk_ack.rcv_mss to 0. This could potentially cause tcp_recvmsg() => tcp_cleanup_rbuf() => __tcp_select_window() call path to have division by 0 issue. So this patch initializes rcv_mss to TCP_MIN_MSS instead of 0. Reported-by: Andrey Konovalov Signed-off-by: Wei Wang Signed-off-by: Eric Dumazet Signed-off-by: Neal Cardwell Signed-off-by: Yuchung Cheng Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net') diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 1e4c76d2b827..842b575f8fdd 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2320,6 +2320,10 @@ int tcp_disconnect(struct sock *sk, int flags) tcp_set_ca_state(sk, TCP_CA_Open); tcp_clear_retrans(tp); inet_csk_delack_init(sk); + /* Initialize rcv_mss to TCP_MIN_MSS to avoid division by 0 + * issue in __tcp_select_window() + */ + icsk->icsk_ack.rcv_mss = TCP_MIN_MSS; tcp_init_send_head(sk); memset(&tp->rx_opt, 0, sizeof(tp->rx_opt)); __sk_dst_reset(sk); -- cgit From 34eb5fe07831458cf8238d54c1fc847dedeaf68c Mon Sep 17 00:00:00 2001 From: Ihar Hrachyshka Date: Thu, 18 May 2017 12:41:18 -0700 Subject: arp: fixed error in a comment the is_garp code deals just with gratuitous ARP packets, not every unsolicited packet. This patch is a result of a discussion in netdev: http://marc.info/?l=linux-netdev&m=149506354216994 Suggested-by: Julian Anastasov Signed-off-by: Ihar Hrachyshka Signed-off-by: David S. Miller --- net/ipv4/arp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index d54345a06f72..053492af8a6e 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -846,7 +846,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) */ is_garp = tip == sip && addr_type == RTN_UNICAST; - /* Unsolicited ARP _replies_ also require target hwaddr to be + /* Gratuitous ARP _replies_ also require target hwaddr to be * the same as source. */ if (is_garp && arp->ar_op == htons(ARPOP_REPLY)) -- cgit From 6fd05633bdafc0ae6ec0d55e61af10780d4d3530 Mon Sep 17 00:00:00 2001 From: Ihar Hrachyshka Date: Thu, 18 May 2017 12:41:19 -0700 Subject: arp: decompose is_garp logic into a separate function The code is quite involving already to earn a separate function for itself. If anything, it helps arp_process readability. Signed-off-by: Ihar Hrachyshka Signed-off-by: David S. Miller --- net/ipv4/arp.c | 35 +++++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 12 deletions(-) (limited to 'net') diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index 053492af8a6e..ca6e1e6c1496 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -641,6 +641,27 @@ void arp_xmit(struct sk_buff *skb) } EXPORT_SYMBOL(arp_xmit); +static bool arp_is_garp(struct net_device *dev, int addr_type, + __be16 ar_op, + __be32 sip, __be32 tip, + unsigned char *sha, unsigned char *tha) +{ + bool is_garp = tip == sip && addr_type == RTN_UNICAST; + + /* Gratuitous ARP _replies_ also require target hwaddr to be + * the same as source. + */ + if (is_garp && ar_op == htons(ARPOP_REPLY)) + is_garp = + /* IPv4 over IEEE 1394 doesn't provide target + * hardware address field in its ARP payload. + */ + tha && + !memcmp(tha, sha, dev->addr_len); + + return is_garp; +} + /* * Process an arp request. */ @@ -844,18 +865,8 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) It is possible, that this option should be enabled for some devices (strip is candidate) */ - is_garp = tip == sip && addr_type == RTN_UNICAST; - - /* Gratuitous ARP _replies_ also require target hwaddr to be - * the same as source. - */ - if (is_garp && arp->ar_op == htons(ARPOP_REPLY)) - is_garp = - /* IPv4 over IEEE 1394 doesn't provide target - * hardware address field in its ARP payload. - */ - tha && - !memcmp(tha, sha, dev->addr_len); + is_garp = arp_is_garp(dev, addr_type, arp->ar_op, + sip, tip, sha, tha); if (!n && ((arp->ar_op == htons(ARPOP_REPLY) && -- cgit From d9ef2e7bf99f59179b89d5c1c4d5b4919375daee Mon Sep 17 00:00:00 2001 From: Ihar Hrachyshka Date: Thu, 18 May 2017 12:41:20 -0700 Subject: arp: postpone addr_type calculation to as late as possible The addr_type retrieval can be costly, so it's worth trying to avoid its calculation as much as possible. This patch makes it calculated only for gratuitous ARP packets. This is especially important since later we may want to move is_garp calculation outside of arp_accept block, at which point the costly operation will be executed for all setups. The patch is the result of a discussion in net-dev: http://marc.info/?l=linux-netdev&m=149506354216994 Suggested-by: Julian Anastasov Signed-off-by: Ihar Hrachyshka Signed-off-by: David S. Miller --- net/ipv4/arp.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) (limited to 'net') diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index ca6e1e6c1496..c22103cec823 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -641,12 +641,12 @@ void arp_xmit(struct sk_buff *skb) } EXPORT_SYMBOL(arp_xmit); -static bool arp_is_garp(struct net_device *dev, int addr_type, - __be16 ar_op, +static bool arp_is_garp(struct net *net, struct net_device *dev, + int *addr_type, __be16 ar_op, __be32 sip, __be32 tip, unsigned char *sha, unsigned char *tha) { - bool is_garp = tip == sip && addr_type == RTN_UNICAST; + bool is_garp = tip == sip; /* Gratuitous ARP _replies_ also require target hwaddr to be * the same as source. @@ -659,6 +659,11 @@ static bool arp_is_garp(struct net_device *dev, int addr_type, tha && !memcmp(tha, sha, dev->addr_len); + if (is_garp) { + *addr_type = inet_addr_type_dev_table(net, dev, sip); + if (*addr_type != RTN_UNICAST) + is_garp = false; + } return is_garp; } @@ -859,18 +864,23 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) n = __neigh_lookup(&arp_tbl, &sip, dev, 0); if (IN_DEV_ARP_ACCEPT(in_dev)) { - unsigned int addr_type = inet_addr_type_dev_table(net, dev, sip); + addr_type = -1; /* Unsolicited ARP is not accepted by default. It is possible, that this option should be enabled for some devices (strip is candidate) */ - is_garp = arp_is_garp(dev, addr_type, arp->ar_op, + is_garp = arp_is_garp(net, dev, &addr_type, arp->ar_op, sip, tip, sha, tha); if (!n && - ((arp->ar_op == htons(ARPOP_REPLY) && - addr_type == RTN_UNICAST) || is_garp)) + (is_garp || + (arp->ar_op == htons(ARPOP_REPLY) && + (addr_type == RTN_UNICAST || + (addr_type < 0 && + /* postpone calculation to as late as possible */ + inet_addr_type_dev_table(net, dev, sip) == + RTN_UNICAST))))) n = __neigh_lookup(&arp_tbl, &sip, dev, 1); } -- cgit From 7d472a59c0e5ec117220a05de6b370447fb6cb66 Mon Sep 17 00:00:00 2001 From: Ihar Hrachyshka Date: Thu, 18 May 2017 12:41:21 -0700 Subject: arp: always override existing neigh entries with gratuitous ARP Currently, when arp_accept is 1, we always override existing neigh entries with incoming gratuitous ARP replies. Otherwise, we override them only if new replies satisfy _locktime_ conditional (packets arrive not earlier than _locktime_ seconds since the last update to the neigh entry). The idea behind locktime is to pick the very first (=> close) reply received in a unicast burst when ARP proxies are used. This helps to avoid ARP thrashing where Linux would switch back and forth from one proxy to another. This logic has nothing to do with gratuitous ARP replies that are generally not aligned in time when multiple IP address carriers send them into network. This patch enforces overriding of existing neigh entries by all incoming gratuitous ARP packets, irrespective of their time of arrival. This will make the kernel honour all incoming gratuitous ARP packets. Signed-off-by: Ihar Hrachyshka Signed-off-by: David S. Miller --- net/ipv4/arp.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'net') diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index c22103cec823..ae96e6f3e0cb 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -863,16 +863,17 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) n = __neigh_lookup(&arp_tbl, &sip, dev, 0); - if (IN_DEV_ARP_ACCEPT(in_dev)) { + if (n || IN_DEV_ARP_ACCEPT(in_dev)) { addr_type = -1; + is_garp = arp_is_garp(net, dev, &addr_type, arp->ar_op, + sip, tip, sha, tha); + } + if (IN_DEV_ARP_ACCEPT(in_dev)) { /* Unsolicited ARP is not accepted by default. It is possible, that this option should be enabled for some devices (strip is candidate) */ - is_garp = arp_is_garp(net, dev, &addr_type, arp->ar_op, - sip, tip, sha, tha); - if (!n && (is_garp || (arp->ar_op == htons(ARPOP_REPLY) && -- cgit From 6d18c732b95c0a9d35e9f978b4438bba15412284 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Fri, 19 May 2017 22:20:29 +0800 Subject: bridge: start hello_timer when enabling KERNEL_STP in br_stp_start Since commit 76b91c32dd86 ("bridge: stp: when using userspace stp stop kernel hello and hold timers"), bridge would not start hello_timer if stp_enabled is not KERNEL_STP when br_dev_open. The problem is even if users set stp_enabled with KERNEL_STP later, the timer will still not be started. It causes that KERNEL_STP can not really work. Users have to re-ifup the bridge to avoid this. This patch is to fix it by starting br->hello_timer when enabling KERNEL_STP in br_stp_start. As an improvement, it's also to start hello_timer again only when br->stp_enabled is KERNEL_STP in br_hello_timer_expired, there is no reason to start the timer again when it's NO_STP. Fixes: 76b91c32dd86 ("bridge: stp: when using userspace stp stop kernel hello and hold timers") Reported-by: Haidong Li Signed-off-by: Xin Long Acked-by: Nikolay Aleksandrov Reviewed-by: Ivan Vecera Signed-off-by: David S. Miller --- net/bridge/br_stp_if.c | 1 + net/bridge/br_stp_timer.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c index 08341d2aa9c9..0db8102995a5 100644 --- a/net/bridge/br_stp_if.c +++ b/net/bridge/br_stp_if.c @@ -179,6 +179,7 @@ static void br_stp_start(struct net_bridge *br) br_debug(br, "using kernel STP\n"); /* To start timers on any ports left in blocking */ + mod_timer(&br->hello_timer, jiffies + br->hello_time); br_port_state_selection(br); } diff --git a/net/bridge/br_stp_timer.c b/net/bridge/br_stp_timer.c index c98b3e5c140a..60b6fe277a8b 100644 --- a/net/bridge/br_stp_timer.c +++ b/net/bridge/br_stp_timer.c @@ -40,7 +40,7 @@ static void br_hello_timer_expired(unsigned long arg) if (br->dev->flags & IFF_UP) { br_config_bpdu_generation(br); - if (br->stp_enabled != BR_USER_STP) + if (br->stp_enabled == BR_KERNEL_STP) mod_timer(&br->hello_timer, round_jiffies(jiffies + br->hello_time)); } -- cgit From 232cd35d0804cc241eb887bb8d4d9b3b9881c64a Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 19 May 2017 14:17:48 -0700 Subject: ipv6: fix out of bound writes in __ip6_append_data() Andrey Konovalov and idaifish@gmail.com reported crashes caused by one skb shared_info being overwritten from __ip6_append_data() Andrey program lead to following state : copy -4200 datalen 2000 fraglen 2040 maxfraglen 2040 alloclen 2048 transhdrlen 0 offset 0 fraggap 6200 The skb_copy_and_csum_bits(skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); is overwriting skb->head and skb_shared_info Since we apparently detect this rare condition too late, move the code earlier to even avoid allocating skb and risking crashes. Once again, many thanks to Andrey and syzkaller team. Signed-off-by: Eric Dumazet Reported-by: Andrey Konovalov Tested-by: Andrey Konovalov Reported-by: Signed-off-by: David S. Miller --- net/ipv6/ip6_output.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'net') diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index d4a31becbd25..bf8a58a1c32d 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1466,6 +1466,11 @@ alloc_new_skb: */ alloclen += sizeof(struct frag_hdr); + copy = datalen - transhdrlen - fraggap; + if (copy < 0) { + err = -EINVAL; + goto error; + } if (transhdrlen) { skb = sock_alloc_send_skb(sk, alloclen + hh_len, @@ -1515,13 +1520,9 @@ alloc_new_skb: data += fraggap; pskb_trim_unique(skb_prev, maxfraglen); } - copy = datalen - transhdrlen - fraggap; - - if (copy < 0) { - err = -EINVAL; - kfree_skb(skb); - goto error; - } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { + if (copy > 0 && + getfrag(from, data + transhdrlen, offset, + copy, fraggap, skb) < 0) { err = -EFAULT; kfree_skb(skb); goto error; -- cgit From 499fde662f1957e3cb8d192a94a099ebe19c714b Mon Sep 17 00:00:00 2001 From: WANG Cong Date: Fri, 19 May 2017 11:21:59 -0700 Subject: vsock: use new wait API for vsock_stream_sendmsg() As reported by Michal, vsock_stream_sendmsg() could still sleep at vsock_stream_has_space() after prepare_to_wait(): vsock_stream_has_space vmci_transport_stream_has_space vmci_qpair_produce_free_space qp_lock qp_acquire_queue_mutex mutex_lock Just switch to the new wait API like we did for commit d9dc8b0f8b4e ("net: fix sleeping for sk_wait_event()"). Reported-by: Michal Kubecek Cc: Stefan Hajnoczi Cc: Jorgen Hansen Cc: "Michael S. Tsirkin" Cc: Claudio Imbrenda Signed-off-by: Cong Wang Reviewed-by: Stefan Hajnoczi Signed-off-by: David S. Miller --- net/vmw_vsock/af_vsock.c | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) (limited to 'net') diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index 6f7f6757ceef..dfc8c51e4d74 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1540,8 +1540,7 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, long timeout; int err; struct vsock_transport_send_notify_data send_data; - - DEFINE_WAIT(wait); + DEFINE_WAIT_FUNC(wait, woken_wake_function); sk = sock->sk; vsk = vsock_sk(sk); @@ -1584,11 +1583,10 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, if (err < 0) goto out; - while (total_written < len) { ssize_t written; - prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); + add_wait_queue(sk_sleep(sk), &wait); while (vsock_stream_has_space(vsk) == 0 && sk->sk_err == 0 && !(sk->sk_shutdown & SEND_SHUTDOWN) && @@ -1597,33 +1595,30 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, /* Don't wait for non-blocking sockets. */ if (timeout == 0) { err = -EAGAIN; - finish_wait(sk_sleep(sk), &wait); + remove_wait_queue(sk_sleep(sk), &wait); goto out_err; } err = transport->notify_send_pre_block(vsk, &send_data); if (err < 0) { - finish_wait(sk_sleep(sk), &wait); + remove_wait_queue(sk_sleep(sk), &wait); goto out_err; } release_sock(sk); - timeout = schedule_timeout(timeout); + timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); lock_sock(sk); if (signal_pending(current)) { err = sock_intr_errno(timeout); - finish_wait(sk_sleep(sk), &wait); + remove_wait_queue(sk_sleep(sk), &wait); goto out_err; } else if (timeout == 0) { err = -EAGAIN; - finish_wait(sk_sleep(sk), &wait); + remove_wait_queue(sk_sleep(sk), &wait); goto out_err; } - - prepare_to_wait(sk_sleep(sk), &wait, - TASK_INTERRUPTIBLE); } - finish_wait(sk_sleep(sk), &wait); + remove_wait_queue(sk_sleep(sk), &wait); /* These checks occur both as part of and after the loop * conditional since we need to check before and after -- cgit From 2d76b2f8b54abd16225cd80afca36ed43f113c41 Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Mon, 22 May 2017 16:46:13 +0200 Subject: net: sched: cls_matchall: fix null pointer dereference Since the head is guaranteed by the check above to be null, the call_rcu would explode. Remove the previously logically dead code that was made logically very much alive and kicking. Fixes: 985538eee06f ("net/sched: remove redundant null check on head") Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- net/sched/cls_matchall.c | 1 - 1 file changed, 1 deletion(-) (limited to 'net') diff --git a/net/sched/cls_matchall.c b/net/sched/cls_matchall.c index dee469fed967..51859b8edd7e 100644 --- a/net/sched/cls_matchall.c +++ b/net/sched/cls_matchall.c @@ -203,7 +203,6 @@ static int mall_change(struct net *net, struct sk_buff *in_skb, *arg = (unsigned long) head; rcu_assign_pointer(tp->root, new); - call_rcu(&head->rcu, mall_destroy_rcu); return 0; err_replace_hw_filter: -- cgit