From 6b1686a71e3158d3c5f125260effce171cc7852b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 28 Oct 2010 12:34:21 +0200 Subject: [PATCH 1/5] netfilter: nf_conntrack: allow nf_ct_alloc_hashtable() to get highmem pages commit ea781f197d6a8 (use SLAB_DESTROY_BY_RCU and get rid of call_rcu()) did a mistake in __vmalloc() call in nf_ct_alloc_hashtable(). I forgot to add __GFP_HIGHMEM, so pages were taken from LOWMEM only. Signed-off-by: Eric Dumazet Cc: stable@kernel.org Signed-off-by: Patrick McHardy --- net/netfilter/nf_conntrack_core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 1eacf8d9966a..27a5ea6b6a0f 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1312,7 +1312,8 @@ void *nf_ct_alloc_hashtable(unsigned int *sizep, int *vmalloced, int nulls) if (!hash) { *vmalloced = 1; printk(KERN_WARNING "nf_conntrack: falling back to vmalloc.\n"); - hash = __vmalloc(sz, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL); + hash = __vmalloc(sz, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, + PAGE_KERNEL); } if (hash && nulls) From 64e46749224aa658d8fc0d37ea83ab20b1d7955d Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Fri, 29 Oct 2010 16:28:07 +0200 Subject: [PATCH 2/5] netfilter: nf_nat: fix compiler warning with CONFIG_NF_CT_NETLINK=n net/ipv4/netfilter/nf_nat_core.c:52: warning: 'nf_nat_proto_find_get' defined but not used net/ipv4/netfilter/nf_nat_core.c:66: warning: 'nf_nat_proto_put' defined but not used Reported-by: Geert Uytterhoeven Signed-off-by: Patrick McHardy --- net/ipv4/netfilter/nf_nat_core.c | 40 ++++++++++++++++---------------- 1 file changed, 20 insertions(+), 20 deletions(-) diff --git a/net/ipv4/netfilter/nf_nat_core.c b/net/ipv4/netfilter/nf_nat_core.c index 295c97431e43..c04787ce1a71 100644 --- a/net/ipv4/netfilter/nf_nat_core.c +++ b/net/ipv4/netfilter/nf_nat_core.c @@ -47,26 +47,6 @@ __nf_nat_proto_find(u_int8_t protonum) return rcu_dereference(nf_nat_protos[protonum]); } -static const struct nf_nat_protocol * -nf_nat_proto_find_get(u_int8_t protonum) -{ - const struct nf_nat_protocol *p; - - rcu_read_lock(); - p = __nf_nat_proto_find(protonum); - if (!try_module_get(p->me)) - p = &nf_nat_unknown_protocol; - rcu_read_unlock(); - - return p; -} - -static void -nf_nat_proto_put(const struct nf_nat_protocol *p) -{ - module_put(p->me); -} - /* We keep an extra hash for each conntrack, for fast searching. */ static inline unsigned int hash_by_src(const struct net *net, u16 zone, @@ -588,6 +568,26 @@ static struct nf_ct_ext_type nat_extend __read_mostly = { #include #include +static const struct nf_nat_protocol * +nf_nat_proto_find_get(u_int8_t protonum) +{ + const struct nf_nat_protocol *p; + + rcu_read_lock(); + p = __nf_nat_proto_find(protonum); + if (!try_module_get(p->me)) + p = &nf_nat_unknown_protocol; + rcu_read_unlock(); + + return p; +} + +static void +nf_nat_proto_put(const struct nf_nat_protocol *p) +{ + module_put(p->me); +} + static const struct nla_policy protonat_nla_policy[CTA_PROTONAT_MAX+1] = { [CTA_PROTONAT_PORT_MIN] = { .type = NLA_U16 }, [CTA_PROTONAT_PORT_MAX] = { .type = NLA_U16 }, From d817d29d0b37290d90b3a9e2a61162f1dbf2be4f Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 29 Oct 2010 19:59:40 +0200 Subject: [PATCH 3/5] netfilter: fix nf_conntrack_l4proto_register() While doing __rcu annotations work on net/netfilter I found following bug. On some arches, it is possible we publish a table while its content is not yet committed to memory, and lockless reader can dereference wild pointer. Signed-off-by: Eric Dumazet Signed-off-by: Patrick McHardy --- net/netfilter/nf_conntrack_proto.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c index ed6d92958023..dc7bb74110df 100644 --- a/net/netfilter/nf_conntrack_proto.c +++ b/net/netfilter/nf_conntrack_proto.c @@ -292,6 +292,12 @@ int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *l4proto) for (i = 0; i < MAX_NF_CT_PROTO; i++) proto_array[i] = &nf_conntrack_l4proto_generic; + + /* Before making proto_array visible to lockless readers, + * we must make sure its content is committed to memory. + */ + smp_wmb(); + nf_ct_protos[l4proto->l3proto] = proto_array; } else if (nf_ct_protos[l4proto->l3proto][l4proto->l4proto] != &nf_conntrack_l4proto_generic) { From 1a8b7a67224eb0c9dbd883b9bfc4938278bad370 Mon Sep 17 00:00:00 2001 From: Vasiliy Kulikov Date: Wed, 3 Nov 2010 08:44:12 +0100 Subject: [PATCH 4/5] ipv4: netfilter: arp_tables: fix information leak to userland Structure arpt_getinfo is copied to userland with the field "name" that has the last elements unitialized. It leads to leaking of contents of kernel stack memory. Signed-off-by: Vasiliy Kulikov Signed-off-by: Patrick McHardy --- net/ipv4/netfilter/arp_tables.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index 3cad2591ace0..3fac340a28d5 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -927,6 +927,7 @@ static int get_info(struct net *net, void __user *user, private = &tmp; } #endif + memset(&info, 0, sizeof(info)); info.valid_hooks = t->valid_hooks; memcpy(info.hook_entry, private->hook_entry, sizeof(info.hook_entry)); From b5f15ac4f89f84853544c934fc7a744289e95e34 Mon Sep 17 00:00:00 2001 From: Vasiliy Kulikov Date: Wed, 3 Nov 2010 08:45:06 +0100 Subject: [PATCH 5/5] ipv4: netfilter: ip_tables: fix information leak to userland Structure ipt_getinfo is copied to userland with the field "name" that has the last elements unitialized. It leads to leaking of contents of kernel stack memory. Signed-off-by: Vasiliy Kulikov Signed-off-by: Patrick McHardy --- net/ipv4/netfilter/ip_tables.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index d31b007a6d80..a846d633b3b6 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1124,6 +1124,7 @@ static int get_info(struct net *net, void __user *user, private = &tmp; } #endif + memset(&info, 0, sizeof(info)); info.valid_hooks = t->valid_hooks; memcpy(info.hook_entry, private->hook_entry, sizeof(info.hook_entry));