From aba36930a35e7f1fe1319b203f25c05d6c119936 Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Sat, 24 Nov 2018 14:21:16 -0500 Subject: net: always initialize pagedlen In ip packet generation, pagedlen is initialized for each skb at the start of the loop in __ip(6)_append_data, before label alloc_new_skb. Depending on compiler options, code can be generated that jumps to this label, triggering use of an an uninitialized variable. In practice, at -O2, the generated code moves the initialization below the label. But the code should not rely on that for correctness. Fixes: 15e36f5b8e98 ("udp: paged allocation with gso") Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller --- net/ipv6/ip6_output.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/ipv6') diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 89e0d5118afe..827a3f5ff3bb 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1354,7 +1354,7 @@ emsgsize: unsigned int fraglen; unsigned int fraggap; unsigned int alloclen; - unsigned int pagedlen = 0; + unsigned int pagedlen; alloc_new_skb: /* There's no room in the current skb */ if (skb) @@ -1378,6 +1378,7 @@ alloc_new_skb: if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len; fraglen = datalen + fragheaderlen; + pagedlen = 0; if ((flags & MSG_MORE) && !(rt->dst.dev->features&NETIF_F_SG)) -- cgit v1.2.3 From 508b09046c0f21678652fb66fd1e9959d55591d2 Mon Sep 17 00:00:00 2001 From: Alin Nastac Date: Wed, 21 Nov 2018 14:00:30 +0100 Subject: netfilter: ipv6: Preserve link scope traffic original oif When ip6_route_me_harder is invoked, it resets outgoing interface of: - link-local scoped packets sent by neighbor discovery - multicast packets sent by MLD host - multicast packets send by MLD proxy daemon that sets outgoing interface through IPV6_PKTINFO ipi6_ifindex Link-local and multicast packets must keep their original oif after ip6_route_me_harder is called. Signed-off-by: Alin Nastac Signed-off-by: Pablo Neira Ayuso --- net/ipv6/netfilter.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/ipv6') diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c index 5ae8e1c51079..8b075f0bc351 100644 --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -24,7 +24,8 @@ int ip6_route_me_harder(struct net *net, struct sk_buff *skb) unsigned int hh_len; struct dst_entry *dst; struct flowi6 fl6 = { - .flowi6_oif = sk ? sk->sk_bound_dev_if : 0, + .flowi6_oif = sk && sk->sk_bound_dev_if ? sk->sk_bound_dev_if : + rt6_need_strict(&iph->daddr) ? skb_dst(skb)->dev->ifindex : 0, .flowi6_mark = skb->mark, .flowi6_uid = sock_net_uid(net, sk), .daddr = iph->daddr, -- cgit v1.2.3 From 584eab291c67894cb17cc87544b9d086228ea70f Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Thu, 22 Nov 2018 19:59:46 +0900 Subject: netfilter: add missing error handling code for register functions register_{netdevice/inetaddr/inet6addr}_notifier may return an error value, this patch adds the code to handle these error paths. Signed-off-by: Taehee Yoo Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/ipv4/nf_nat_masquerade.h | 2 +- include/net/netfilter/ipv6/nf_nat_masquerade.h | 2 +- net/ipv4/netfilter/ipt_MASQUERADE.c | 7 ++++-- net/ipv4/netfilter/nf_nat_masquerade_ipv4.c | 21 +++++++++++++---- net/ipv4/netfilter/nft_masq_ipv4.c | 4 +++- net/ipv6/netfilter/ip6t_MASQUERADE.c | 8 +++++-- net/ipv6/netfilter/nf_nat_masquerade_ipv6.c | 32 ++++++++++++++++++-------- net/ipv6/netfilter/nft_masq_ipv6.c | 4 +++- net/netfilter/nft_flow_offload.c | 5 +++- 9 files changed, 63 insertions(+), 22 deletions(-) (limited to 'net/ipv6') diff --git a/include/net/netfilter/ipv4/nf_nat_masquerade.h b/include/net/netfilter/ipv4/nf_nat_masquerade.h index cd24be4c4a99..13d55206bb9f 100644 --- a/include/net/netfilter/ipv4/nf_nat_masquerade.h +++ b/include/net/netfilter/ipv4/nf_nat_masquerade.h @@ -9,7 +9,7 @@ nf_nat_masquerade_ipv4(struct sk_buff *skb, unsigned int hooknum, const struct nf_nat_range2 *range, const struct net_device *out); -void nf_nat_masquerade_ipv4_register_notifier(void); +int nf_nat_masquerade_ipv4_register_notifier(void); void nf_nat_masquerade_ipv4_unregister_notifier(void); #endif /*_NF_NAT_MASQUERADE_IPV4_H_ */ diff --git a/include/net/netfilter/ipv6/nf_nat_masquerade.h b/include/net/netfilter/ipv6/nf_nat_masquerade.h index 0c3b5ebf0bb8..2917bf95c437 100644 --- a/include/net/netfilter/ipv6/nf_nat_masquerade.h +++ b/include/net/netfilter/ipv6/nf_nat_masquerade.h @@ -5,7 +5,7 @@ unsigned int nf_nat_masquerade_ipv6(struct sk_buff *skb, const struct nf_nat_range2 *range, const struct net_device *out); -void nf_nat_masquerade_ipv6_register_notifier(void); +int nf_nat_masquerade_ipv6_register_notifier(void); void nf_nat_masquerade_ipv6_unregister_notifier(void); #endif /* _NF_NAT_MASQUERADE_IPV6_H_ */ diff --git a/net/ipv4/netfilter/ipt_MASQUERADE.c b/net/ipv4/netfilter/ipt_MASQUERADE.c index ce1512b02cb2..fd3f9e8a74da 100644 --- a/net/ipv4/netfilter/ipt_MASQUERADE.c +++ b/net/ipv4/netfilter/ipt_MASQUERADE.c @@ -81,9 +81,12 @@ static int __init masquerade_tg_init(void) int ret; ret = xt_register_target(&masquerade_tg_reg); + if (ret) + return ret; - if (ret == 0) - nf_nat_masquerade_ipv4_register_notifier(); + ret = nf_nat_masquerade_ipv4_register_notifier(); + if (ret) + xt_unregister_target(&masquerade_tg_reg); return ret; } diff --git a/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c b/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c index a9d5e013e555..c7d7fa4fc369 100644 --- a/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c +++ b/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c @@ -149,16 +149,29 @@ static struct notifier_block masq_inet_notifier = { static atomic_t masquerade_notifier_refcount = ATOMIC_INIT(0); -void nf_nat_masquerade_ipv4_register_notifier(void) +int nf_nat_masquerade_ipv4_register_notifier(void) { + int ret; + /* check if the notifier was already set */ if (atomic_inc_return(&masquerade_notifier_refcount) > 1) - return; + return 0; /* Register for device down reports */ - register_netdevice_notifier(&masq_dev_notifier); + ret = register_netdevice_notifier(&masq_dev_notifier); + if (ret) + goto err_dec; /* Register IP address change reports */ - register_inetaddr_notifier(&masq_inet_notifier); + ret = register_inetaddr_notifier(&masq_inet_notifier); + if (ret) + goto err_unregister; + + return ret; +err_unregister: + unregister_netdevice_notifier(&masq_dev_notifier); +err_dec: + atomic_dec(&masquerade_notifier_refcount); + return ret; } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv4_register_notifier); diff --git a/net/ipv4/netfilter/nft_masq_ipv4.c b/net/ipv4/netfilter/nft_masq_ipv4.c index f1193e1e928a..6847de1d1db8 100644 --- a/net/ipv4/netfilter/nft_masq_ipv4.c +++ b/net/ipv4/netfilter/nft_masq_ipv4.c @@ -69,7 +69,9 @@ static int __init nft_masq_ipv4_module_init(void) if (ret < 0) return ret; - nf_nat_masquerade_ipv4_register_notifier(); + ret = nf_nat_masquerade_ipv4_register_notifier(); + if (ret) + nft_unregister_expr(&nft_masq_ipv4_type); return ret; } diff --git a/net/ipv6/netfilter/ip6t_MASQUERADE.c b/net/ipv6/netfilter/ip6t_MASQUERADE.c index 491f808e356a..29c7f1915a96 100644 --- a/net/ipv6/netfilter/ip6t_MASQUERADE.c +++ b/net/ipv6/netfilter/ip6t_MASQUERADE.c @@ -58,8 +58,12 @@ static int __init masquerade_tg6_init(void) int err; err = xt_register_target(&masquerade_tg6_reg); - if (err == 0) - nf_nat_masquerade_ipv6_register_notifier(); + if (err) + return err; + + err = nf_nat_masquerade_ipv6_register_notifier(); + if (err) + xt_unregister_target(&masquerade_tg6_reg); return err; } diff --git a/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c b/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c index 3e4bf2286abe..7afd1e63d2db 100644 --- a/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c +++ b/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c @@ -132,8 +132,8 @@ static void iterate_cleanup_work(struct work_struct *work) * of ipv6 addresses being deleted), we also need to add an upper * limit to the number of queued work items. */ -static int masq_inet_event(struct notifier_block *this, - unsigned long event, void *ptr) +static int masq_inet6_event(struct notifier_block *this, + unsigned long event, void *ptr) { struct inet6_ifaddr *ifa = ptr; const struct net_device *dev; @@ -171,20 +171,34 @@ static int masq_inet_event(struct notifier_block *this, return NOTIFY_DONE; } -static struct notifier_block masq_inet_notifier = { - .notifier_call = masq_inet_event, +static struct notifier_block masq_inet6_notifier = { + .notifier_call = masq_inet6_event, }; static atomic_t masquerade_notifier_refcount = ATOMIC_INIT(0); -void nf_nat_masquerade_ipv6_register_notifier(void) +int nf_nat_masquerade_ipv6_register_notifier(void) { + int ret; + /* check if the notifier is already set */ if (atomic_inc_return(&masquerade_notifier_refcount) > 1) - return; + return 0; - register_netdevice_notifier(&masq_dev_notifier); - register_inet6addr_notifier(&masq_inet_notifier); + ret = register_netdevice_notifier(&masq_dev_notifier); + if (ret) + goto err_dec; + + ret = register_inet6addr_notifier(&masq_inet6_notifier); + if (ret) + goto err_unregister; + + return ret; +err_unregister: + unregister_netdevice_notifier(&masq_dev_notifier); +err_dec: + atomic_dec(&masquerade_notifier_refcount); + return ret; } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv6_register_notifier); @@ -194,7 +208,7 @@ void nf_nat_masquerade_ipv6_unregister_notifier(void) if (atomic_dec_return(&masquerade_notifier_refcount) > 0) return; - unregister_inet6addr_notifier(&masq_inet_notifier); + unregister_inet6addr_notifier(&masq_inet6_notifier); unregister_netdevice_notifier(&masq_dev_notifier); } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv6_unregister_notifier); diff --git a/net/ipv6/netfilter/nft_masq_ipv6.c b/net/ipv6/netfilter/nft_masq_ipv6.c index dd0122f3cffe..e06c82e9dfcd 100644 --- a/net/ipv6/netfilter/nft_masq_ipv6.c +++ b/net/ipv6/netfilter/nft_masq_ipv6.c @@ -70,7 +70,9 @@ static int __init nft_masq_ipv6_module_init(void) if (ret < 0) return ret; - nf_nat_masquerade_ipv6_register_notifier(); + ret = nf_nat_masquerade_ipv6_register_notifier(); + if (ret) + nft_unregister_expr(&nft_masq_ipv6_type); return ret; } diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c index e82d9a966c45..974525eb92df 100644 --- a/net/netfilter/nft_flow_offload.c +++ b/net/netfilter/nft_flow_offload.c @@ -214,7 +214,9 @@ static int __init nft_flow_offload_module_init(void) { int err; - register_netdevice_notifier(&flow_offload_netdev_notifier); + err = register_netdevice_notifier(&flow_offload_netdev_notifier); + if (err) + goto err; err = nft_register_expr(&nft_flow_offload_type); if (err < 0) @@ -224,6 +226,7 @@ static int __init nft_flow_offload_module_init(void) register_expr: unregister_netdevice_notifier(&flow_offload_netdev_notifier); +err: return err; } -- cgit v1.2.3 From 095faf45e64be00bff4da2d6182dface3d69c9b7 Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Thu, 22 Nov 2018 19:59:57 +0900 Subject: netfilter: nat: fix double register in masquerade modules There is a reference counter to ensure that masquerade modules register notifiers only once. However, the existing reference counter approach is not safe, test commands are: while : do modprobe ip6t_MASQUERADE & modprobe nft_masq_ipv6 & modprobe -rv ip6t_MASQUERADE & modprobe -rv nft_masq_ipv6 & done numbers below represent the reference counter. -------------------------------------------------------- CPU0 CPU1 CPU2 CPU3 CPU4 [insmod] [insmod] [rmmod] [rmmod] [insmod] -------------------------------------------------------- 0->1 register 1->2 returns 2->1 returns 1->0 0->1 register <-- unregister -------------------------------------------------------- The unregistation of CPU3 should be processed before the registration of CPU4. In order to fix this, use a mutex instead of reference counter. splat looks like: [ 323.869557] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [modprobe:1381] [ 323.869574] Modules linked in: nf_tables(+) nf_nat_ipv6(-) nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 n] [ 323.869574] irq event stamp: 194074 [ 323.898930] hardirqs last enabled at (194073): [] trace_hardirqs_on_thunk+0x1a/0x1c [ 323.898930] hardirqs last disabled at (194074): [] trace_hardirqs_off_thunk+0x1a/0x1c [ 323.898930] softirqs last enabled at (182132): [] __do_softirq+0x6ec/0xa3b [ 323.898930] softirqs last disabled at (182109): [] irq_exit+0x1a6/0x1e0 [ 323.898930] CPU: 0 PID: 1381 Comm: modprobe Not tainted 4.20.0-rc2+ #27 [ 323.898930] RIP: 0010:raw_notifier_chain_register+0xea/0x240 [ 323.898930] Code: 3c 03 0f 8e f2 00 00 00 44 3b 6b 10 7f 4d 49 bc 00 00 00 00 00 fc ff df eb 22 48 8d 7b 10 488 [ 323.898930] RSP: 0018:ffff888101597218 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13 [ 323.898930] RAX: 0000000000000000 RBX: ffffffffc04361c0 RCX: 0000000000000000 [ 323.898930] RDX: 1ffffffff26132ae RSI: ffffffffc04aa3c0 RDI: ffffffffc04361d0 [ 323.898930] RBP: ffffffffc04361c8 R08: 0000000000000000 R09: 0000000000000001 [ 323.898930] R10: ffff8881015972b0 R11: fffffbfff26132c4 R12: dffffc0000000000 [ 323.898930] R13: 0000000000000000 R14: 1ffff110202b2e44 R15: ffffffffc04aa3c0 [ 323.898930] FS: 00007f813ed41540(0000) GS:ffff88811ae00000(0000) knlGS:0000000000000000 [ 323.898930] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 323.898930] CR2: 0000559bf2c9f120 CR3: 000000010bc80000 CR4: 00000000001006f0 [ 323.898930] Call Trace: [ 323.898930] ? atomic_notifier_chain_register+0x2d0/0x2d0 [ 323.898930] ? down_read+0x150/0x150 [ 323.898930] ? sched_clock_cpu+0x126/0x170 [ 323.898930] ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables] [ 323.898930] ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables] [ 323.898930] register_netdevice_notifier+0xbb/0x790 [ 323.898930] ? __dev_close_many+0x2d0/0x2d0 [ 323.898930] ? __mutex_unlock_slowpath+0x17f/0x740 [ 323.898930] ? wait_for_completion+0x710/0x710 [ 323.898930] ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables] [ 323.898930] ? up_write+0x6c/0x210 [ 323.898930] ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables] [ 324.127073] ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables] [ 324.127073] nft_chain_filter_init+0x1e/0xe8a [nf_tables] [ 324.127073] nf_tables_module_init+0x37/0x92 [nf_tables] [ ... ] Fixes: 8dd33cc93ec9 ("netfilter: nf_nat: generalize IPv4 masquerading support for nf_tables") Fixes: be6b635cd674 ("netfilter: nf_nat: generalize IPv6 masquerading support for nf_tables") Signed-off-by: Taehee Yoo Signed-off-by: Pablo Neira Ayuso --- net/ipv4/netfilter/nf_nat_masquerade_ipv4.c | 23 ++++++++++++++++------- net/ipv6/netfilter/nf_nat_masquerade_ipv6.c | 23 ++++++++++++++++------- 2 files changed, 32 insertions(+), 14 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c b/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c index c7d7fa4fc369..41327bb99093 100644 --- a/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c +++ b/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c @@ -147,15 +147,17 @@ static struct notifier_block masq_inet_notifier = { .notifier_call = masq_inet_event, }; -static atomic_t masquerade_notifier_refcount = ATOMIC_INIT(0); +static int masq_refcnt; +static DEFINE_MUTEX(masq_mutex); int nf_nat_masquerade_ipv4_register_notifier(void) { - int ret; + int ret = 0; + mutex_lock(&masq_mutex); /* check if the notifier was already set */ - if (atomic_inc_return(&masquerade_notifier_refcount) > 1) - return 0; + if (++masq_refcnt > 1) + goto out_unlock; /* Register for device down reports */ ret = register_netdevice_notifier(&masq_dev_notifier); @@ -166,22 +168,29 @@ int nf_nat_masquerade_ipv4_register_notifier(void) if (ret) goto err_unregister; + mutex_unlock(&masq_mutex); return ret; + err_unregister: unregister_netdevice_notifier(&masq_dev_notifier); err_dec: - atomic_dec(&masquerade_notifier_refcount); + masq_refcnt--; +out_unlock: + mutex_unlock(&masq_mutex); return ret; } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv4_register_notifier); void nf_nat_masquerade_ipv4_unregister_notifier(void) { + mutex_lock(&masq_mutex); /* check if the notifier still has clients */ - if (atomic_dec_return(&masquerade_notifier_refcount) > 0) - return; + if (--masq_refcnt > 0) + goto out_unlock; unregister_netdevice_notifier(&masq_dev_notifier); unregister_inetaddr_notifier(&masq_inet_notifier); +out_unlock: + mutex_unlock(&masq_mutex); } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv4_unregister_notifier); diff --git a/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c b/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c index 7afd1e63d2db..0ad0da5a2600 100644 --- a/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c +++ b/net/ipv6/netfilter/nf_nat_masquerade_ipv6.c @@ -175,15 +175,17 @@ static struct notifier_block masq_inet6_notifier = { .notifier_call = masq_inet6_event, }; -static atomic_t masquerade_notifier_refcount = ATOMIC_INIT(0); +static int masq_refcnt; +static DEFINE_MUTEX(masq_mutex); int nf_nat_masquerade_ipv6_register_notifier(void) { - int ret; + int ret = 0; + mutex_lock(&masq_mutex); /* check if the notifier is already set */ - if (atomic_inc_return(&masquerade_notifier_refcount) > 1) - return 0; + if (++masq_refcnt > 1) + goto out_unlock; ret = register_netdevice_notifier(&masq_dev_notifier); if (ret) @@ -193,22 +195,29 @@ int nf_nat_masquerade_ipv6_register_notifier(void) if (ret) goto err_unregister; + mutex_unlock(&masq_mutex); return ret; + err_unregister: unregister_netdevice_notifier(&masq_dev_notifier); err_dec: - atomic_dec(&masquerade_notifier_refcount); + masq_refcnt--; +out_unlock: + mutex_unlock(&masq_mutex); return ret; } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv6_register_notifier); void nf_nat_masquerade_ipv6_unregister_notifier(void) { + mutex_lock(&masq_mutex); /* check if the notifier still has clients */ - if (atomic_dec_return(&masquerade_notifier_refcount) > 0) - return; + if (--masq_refcnt > 0) + goto out_unlock; unregister_inet6addr_notifier(&masq_inet6_notifier); unregister_netdevice_notifier(&masq_dev_notifier); +out_unlock: + mutex_unlock(&masq_mutex); } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv6_unregister_notifier); -- cgit v1.2.3