From 848edc69192a38bf9d261032f248b14f47e6af8b Mon Sep 17 00:00:00 2001 From: Santosh Nayak Date: Tue, 6 Mar 2012 01:22:50 +0000 Subject: netfilter: ebtables: fix wrong name length while copying to user-space user-space ebtables expects 32 bytes-long names, but xt_match names use 29 bytes. We have to copy less 29 bytes and then, make sure we fill the remaining bytes with zeroes. Signed-off-by: Santosh Nayak Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller --- net/bridge/netfilter/ebtables.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'net/bridge') diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 8aa4ad0..15e9575 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1335,7 +1335,12 @@ static inline int ebt_make_matchname(const struct ebt_entry_match *m, const char *base, char __user *ubase) { char __user *hlp = ubase + ((char *)m - base); - if (copy_to_user(hlp, m->u.match->name, EBT_FUNCTION_MAXNAMELEN)) + char name[EBT_FUNCTION_MAXNAMELEN] = {}; + + /* ebtables expects 32 bytes long names but xt_match names are 29 bytes + long. Copy 29 bytes and fill remaining bytes with zeroes. */ + strncpy(name, m->u.match->name, sizeof(name)); + if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) return -EFAULT; return 0; } @@ -1344,7 +1349,10 @@ static inline int ebt_make_watchername(const struct ebt_entry_watcher *w, const char *base, char __user *ubase) { char __user *hlp = ubase + ((char *)w - base); - if (copy_to_user(hlp , w->u.watcher->name, EBT_FUNCTION_MAXNAMELEN)) + char name[EBT_FUNCTION_MAXNAMELEN] = {}; + + strncpy(name, w->u.watcher->name, sizeof(name)); + if (copy_to_user(hlp , name, EBT_FUNCTION_MAXNAMELEN)) return -EFAULT; return 0; } @@ -1355,10 +1363,12 @@ ebt_make_names(struct ebt_entry *e, const char *base, char __user *ubase) int ret; char __user *hlp; const struct ebt_entry_target *t; + char name[EBT_FUNCTION_MAXNAMELEN] = {}; if (e->bitmask == 0) return 0; + strncpy(name, t->u.target->name, sizeof(name)); hlp = ubase + (((char *)e + e->target_offset) - base); t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); @@ -1368,7 +1378,7 @@ ebt_make_names(struct ebt_entry *e, const char *base, char __user *ubase) ret = EBT_WATCHER_ITERATE(e, ebt_make_watchername, base, ubase); if (ret != 0) return ret; - if (copy_to_user(hlp, t->u.target->name, EBT_FUNCTION_MAXNAMELEN)) + if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) return -EFAULT; return 0; } -- cgit v1.1 From a157b9d5b5b626e46eba2ac4e342da8db25cabc4 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 6 Mar 2012 01:22:53 +0000 Subject: netfilter: bridge: fix wrong pointer dereference In adf7ff8, a invalid dereference was added in ebt_make_names. CC [M] net/bridge/netfilter/ebtables.o net/bridge/netfilter/ebtables.c: In function `ebt_make_names': net/bridge/netfilter/ebtables.c:1371:20: warning: `t' may be used uninitialized in this function [-Wuninitialized] Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller --- net/bridge/netfilter/ebtables.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/bridge') diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 15e9575..5fe2ff3 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1368,7 +1368,6 @@ ebt_make_names(struct ebt_entry *e, const char *base, char __user *ubase) if (e->bitmask == 0) return 0; - strncpy(name, t->u.target->name, sizeof(name)); hlp = ubase + (((char *)e + e->target_offset) - base); t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); @@ -1378,6 +1377,7 @@ ebt_make_names(struct ebt_entry *e, const char *base, char __user *ubase) ret = EBT_WATCHER_ITERATE(e, ebt_make_watchername, base, ubase); if (ret != 0) return ret; + strncpy(name, t->u.target->name, sizeof(name)); if (copy_to_user(hlp, name, EBT_FUNCTION_MAXNAMELEN)) return -EFAULT; return 0; -- cgit v1.1 From 739e4505a0e8209622dc71743bfa1c804eacf7f4 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 6 Mar 2012 01:22:54 +0000 Subject: bridge: netfilter: don't call iptables on vlan packets if sysctl is off When net.bridge.bridge-nf-filter-vlan-tagged is 0 (default), vlan packets arriving should not be sent to ip(6)tables by bridge netfilter. However, it turns out that we currently always send VLAN packets to netfilter, if .. a), CONFIG_VLAN_8021Q is enabled ; or b), CONFIG_VLAN_8021Q is not set but rx vlan offload is enabled on the bridge port. This is because bridge netfilter treats skb with skb->protocol == ETH_P_IP{V6} as "non-vlan packet". With rx vlan offload on or CONFIG_VLAN_8021Q=y, the vlan header has already been removed here, and we cannot rely on skb->protocol alone. Fix this by only using skb->protocol if the skb has no vlan tag, or if a vlan tag is present and filter-vlan-tagged bridge netfilter sysctl is enabled. We cannot remove the skb->protocol == htons(ETH_P_8021Q) test because the vlan tag is still around in the CONFIG_VLAN_8021Q=n && "ethtool -K $itf rxvlan off" case. reproducer: iptables -t raw -I PREROUTING -i br0 iptables -t raw -I PREROUTING -i br0.1 Then send packets to an ip address configured on br0.1 interface. Even with net.bridge.bridge-nf-filter-vlan-tagged=0, the 1st rule will match instead of the 2nd one. With this patch applied, the 2nd rule will match instead. In the non-local address case, netfilter won't be consulted after this patch unless the sysctl is switched on. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller --- net/bridge/br_netfilter.c | 32 ++++++++++++++++++-------------- 1 file changed, 18 insertions(+), 14 deletions(-) (limited to 'net/bridge') diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index 8412247..dec4f38 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -62,6 +62,15 @@ static int brnf_filter_pppoe_tagged __read_mostly = 0; #define brnf_filter_pppoe_tagged 0 #endif +#define IS_IP(skb) \ + (!vlan_tx_tag_present(skb) && skb->protocol == htons(ETH_P_IP)) + +#define IS_IPV6(skb) \ + (!vlan_tx_tag_present(skb) && skb->protocol == htons(ETH_P_IPV6)) + +#define IS_ARP(skb) \ + (!vlan_tx_tag_present(skb) && skb->protocol == htons(ETH_P_ARP)) + static inline __be16 vlan_proto(const struct sk_buff *skb) { if (vlan_tx_tag_present(skb)) @@ -639,8 +648,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff *skb, return NF_DROP; br = p->br; - if (skb->protocol == htons(ETH_P_IPV6) || IS_VLAN_IPV6(skb) || - IS_PPPOE_IPV6(skb)) { + if (IS_IPV6(skb) || IS_VLAN_IPV6(skb) || IS_PPPOE_IPV6(skb)) { if (!brnf_call_ip6tables && !br->nf_call_ip6tables) return NF_ACCEPT; @@ -651,8 +659,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff *skb, if (!brnf_call_iptables && !br->nf_call_iptables) return NF_ACCEPT; - if (skb->protocol != htons(ETH_P_IP) && !IS_VLAN_IP(skb) && - !IS_PPPOE_IP(skb)) + if (!IS_IP(skb) && !IS_VLAN_IP(skb) && !IS_PPPOE_IP(skb)) return NF_ACCEPT; nf_bridge_pull_encap_header_rcsum(skb); @@ -701,7 +708,7 @@ static int br_nf_forward_finish(struct sk_buff *skb) struct nf_bridge_info *nf_bridge = skb->nf_bridge; struct net_device *in; - if (skb->protocol != htons(ETH_P_ARP) && !IS_VLAN_ARP(skb)) { + if (!IS_ARP(skb) && !IS_VLAN_ARP(skb)) { in = nf_bridge->physindev; if (nf_bridge->mask & BRNF_PKT_TYPE) { skb->pkt_type = PACKET_OTHERHOST; @@ -718,6 +725,7 @@ static int br_nf_forward_finish(struct sk_buff *skb) return 0; } + /* This is the 'purely bridged' case. For IP, we pass the packet to * netfilter with indev and outdev set to the bridge device, * but we are still able to filter on the 'real' indev/outdev @@ -744,11 +752,9 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff *skb, if (!parent) return NF_DROP; - if (skb->protocol == htons(ETH_P_IP) || IS_VLAN_IP(skb) || - IS_PPPOE_IP(skb)) + if (IS_IP(skb) || IS_VLAN_IP(skb) || IS_PPPOE_IP(skb)) pf = PF_INET; - else if (skb->protocol == htons(ETH_P_IPV6) || IS_VLAN_IPV6(skb) || - IS_PPPOE_IPV6(skb)) + else if (IS_IPV6(skb) || IS_VLAN_IPV6(skb) || IS_PPPOE_IPV6(skb)) pf = PF_INET6; else return NF_ACCEPT; @@ -795,7 +801,7 @@ static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff *skb, if (!brnf_call_arptables && !br->nf_call_arptables) return NF_ACCEPT; - if (skb->protocol != htons(ETH_P_ARP)) { + if (!IS_ARP(skb)) { if (!IS_VLAN_ARP(skb)) return NF_ACCEPT; nf_bridge_pull_encap_header(skb); @@ -853,11 +859,9 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff *skb, if (!realoutdev) return NF_DROP; - if (skb->protocol == htons(ETH_P_IP) || IS_VLAN_IP(skb) || - IS_PPPOE_IP(skb)) + if (IS_IP(skb) || IS_VLAN_IP(skb) || IS_PPPOE_IP(skb)) pf = PF_INET; - else if (skb->protocol == htons(ETH_P_IPV6) || IS_VLAN_IPV6(skb) || - IS_PPPOE_IPV6(skb)) + else if (IS_IPV6(skb) || IS_VLAN_IPV6(skb) || IS_PPPOE_IPV6(skb)) pf = PF_INET6; else return NF_ACCEPT; -- cgit v1.1 From d9e179ecec0805c41b17f9a0c3b925d415677772 Mon Sep 17 00:00:00 2001 From: Paulius Zaleckas Date: Tue, 6 Mar 2012 22:25:14 +0000 Subject: bridge: br_log_state() s/entering/entered/ When br_log_state() is reporting state it should say "entered" istead of "entering" since state at this point is already changed. Signed-off-by: Paulius Zaleckas Signed-off-by: David S. Miller --- net/bridge/br_stp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/bridge') diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c index 6751ed4..8c836d9 100644 --- a/net/bridge/br_stp.c +++ b/net/bridge/br_stp.c @@ -31,7 +31,7 @@ static const char *const br_port_state_names[] = { void br_log_state(const struct net_bridge_port *p) { - br_info(p->br, "port %u(%s) entering %s state\n", + br_info(p->br, "port %u(%s) entered %s state\n", (unsigned) p->port_no, p->dev->name, br_port_state_names[p->state]); } -- cgit v1.1 From 5200959b833ddacf28b6ffce8c331dfd6e0ca797 Mon Sep 17 00:00:00 2001 From: Paulius Zaleckas Date: Tue, 6 Mar 2012 22:25:22 +0000 Subject: bridge: fix state reporting when port is disabled Now we have: eth0: link *down* br0: port 1(eth0) entered *forwarding* state br_log_state(p) should be called *after* p->state is set to BR_STATE_DISABLED. Reported-by: Zilvinas Valinskas Signed-off-by: Paulius Zaleckas Acked-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/bridge/br_stp_if.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'net/bridge') diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c index 19308e3..f494496 100644 --- a/net/bridge/br_stp_if.c +++ b/net/bridge/br_stp_if.c @@ -98,14 +98,13 @@ void br_stp_disable_port(struct net_bridge_port *p) struct net_bridge *br = p->br; int wasroot; - br_log_state(p); - wasroot = br_is_root_bridge(br); br_become_designated_port(p); p->state = BR_STATE_DISABLED; p->topology_change_ack = 0; p->config_pending = 0; + br_log_state(p); br_ifinfo_notify(RTM_NEWLINK, p); del_timer(&p->message_age_timer); -- cgit v1.1