From dc15af8e9dbd039ebb06336597d2c491ef46ab74 Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Tue, 25 Feb 2020 10:05:47 +0300 Subject: [PATCH 01/11] netfilter: nf_conntrack: ct_cpu_seq_next should increase position index If .next function does not change position index, following .show function will repeat output related to current position index. Cc: stable@vger.kernel.org Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code ...") Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_standalone.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c index 410809c669e11..4912069627b65 100644 --- a/net/netfilter/nf_conntrack_standalone.c +++ b/net/netfilter/nf_conntrack_standalone.c @@ -411,7 +411,7 @@ static void *ct_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) *pos = cpu + 1; return per_cpu_ptr(net->ct.stat, cpu); } - + (*pos)++; return NULL; } From bb71f846a0002239f7058c84f1496648ff4a5c20 Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Tue, 25 Feb 2020 10:05:59 +0300 Subject: [PATCH 02/11] netfilter: synproxy: synproxy_cpu_seq_next should increase position index If .next function does not change position index, following .show function will repeat output related to current position index. Cc: stable@vger.kernel.org Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code ...") Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_synproxy_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netfilter/nf_synproxy_core.c b/net/netfilter/nf_synproxy_core.c index b0930d4aba228..b9cbe1e2453e8 100644 --- a/net/netfilter/nf_synproxy_core.c +++ b/net/netfilter/nf_synproxy_core.c @@ -267,7 +267,7 @@ static void *synproxy_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) *pos = cpu + 1; return per_cpu_ptr(snet->stats, cpu); } - + (*pos)++; return NULL; } From db25517a550926f609c63054b12ea9ad515e1a10 Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Tue, 25 Feb 2020 10:06:29 +0300 Subject: [PATCH 03/11] netfilter: xt_recent: recent_seq_next should increase position index If .next function does not change position index, following .show function will repeat output related to current position index. Without the patch: # dd if=/proc/net/xt_recent/SSH # original file outpt src=127.0.0.4 ttl: 0 last_seen: 6275444819 oldest_pkt: 1 6275444819 src=127.0.0.2 ttl: 0 last_seen: 6275438906 oldest_pkt: 1 6275438906 src=127.0.0.3 ttl: 0 last_seen: 6275441953 oldest_pkt: 1 6275441953 0+1 records in 0+1 records out 204 bytes copied, 6.1332e-05 s, 3.3 MB/s Read after lseek into middle of last line (offset 140 in example below) generates expected end of last line and then unexpected whole last line once again # dd if=/proc/net/xt_recent/SSH bs=140 skip=1 dd: /proc/net/xt_recent/SSH: cannot skip to specified offset 127.0.0.3 ttl: 0 last_seen: 6275441953 oldest_pkt: 1 6275441953 src=127.0.0.3 ttl: 0 last_seen: 6275441953 oldest_pkt: 1 6275441953 0+1 records in 0+1 records out 132 bytes copied, 6.2487e-05 s, 2.1 MB/s Cc: stable@vger.kernel.org Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code ...") Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin Signed-off-by: Pablo Neira Ayuso --- net/netfilter/xt_recent.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c index 0a9708004e205..225a7ab6d79a9 100644 --- a/net/netfilter/xt_recent.c +++ b/net/netfilter/xt_recent.c @@ -492,12 +492,12 @@ static void *recent_seq_next(struct seq_file *seq, void *v, loff_t *pos) const struct recent_entry *e = v; const struct list_head *head = e->list.next; + (*pos)++; while (head == &t->iphash[st->bucket]) { if (++st->bucket >= ip_list_hash_size) return NULL; head = t->iphash[st->bucket].next; } - (*pos)++; return list_entry(head, struct recent_entry, list); } From ee84f19cbbe9cf7cba2958acb03163fed3ecbb0f Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Tue, 25 Feb 2020 10:07:12 +0300 Subject: [PATCH 04/11] netfilter: x_tables: xt_mttg_seq_next should increase position index If .next function does not change position index, following .show function will repeat output related to current position index. Without patch: # dd if=/proc/net/ip_tables_matches # original file output conntrack conntrack conntrack recent recent icmp udplite udp tcp 0+1 records in 0+1 records out 65 bytes copied, 5.4074e-05 s, 1.2 MB/s # dd if=/proc/net/ip_tables_matches bs=62 skip=1 dd: /proc/net/ip_tables_matches: cannot skip to specified offset cp <<< end of last line tcp <<< and then unexpected whole last line once again 0+1 records in 0+1 records out 7 bytes copied, 0.000102447 s, 68.3 kB/s Cc: stable@vger.kernel.org Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code ...") Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin Signed-off-by: Pablo Neira Ayuso --- net/netfilter/x_tables.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index e27c6c5ba9df8..cd2b034eef59a 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -1551,6 +1551,9 @@ static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos, uint8_t nfproto = (unsigned long)PDE_DATA(file_inode(seq->file)); struct nf_mttg_trav *trav = seq->private; + if (ppos != NULL) + ++(*ppos); + switch (trav->class) { case MTTG_TRAV_INIT: trav->class = MTTG_TRAV_NFP_UNSPEC; @@ -1576,9 +1579,6 @@ static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos, default: return NULL; } - - if (ppos != NULL) - ++*ppos; return trav; } From 2d285f26ecd072800a29c5b71e63437f21ef830a Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 2 Mar 2020 21:58:50 +0100 Subject: [PATCH 05/11] netfilter: nf_tables: free flowtable hooks on hook register error If hook registration fails, the hooks allocated via nft_netdev_hook_alloc need to be freed. We can't change the goto label to 'goto 5' -- while it does fix the memleak it does cause a warning splat from the netfilter core (the hooks were not registered). Fixes: 3f0465a9ef02 ("netfilter: nf_tables: dynamically allocate hooks per net_device in flowtables") Reported-by: syzbot+a2ff6fa45162a5ed4dd3@syzkaller.appspotmail.com Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index d1318bdf49ca9..bb064aa4154b4 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -6300,8 +6300,13 @@ static int nf_tables_newflowtable(struct net *net, struct sock *nlsk, goto err4; err = nft_register_flowtable_net_hooks(ctx.net, table, flowtable); - if (err < 0) + if (err < 0) { + list_for_each_entry_safe(hook, next, &flowtable->hook_list, list) { + list_del_rcu(&hook->list); + kfree_rcu(hook, rcu); + } goto err4; + } err = nft_trans_flowtable_add(&ctx, NFT_MSG_NEWFLOWTABLE, flowtable); if (err < 0) From c049b3450072b8e3998053490e025839fecfef31 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 2 Mar 2020 21:08:31 -0800 Subject: [PATCH 06/11] netfilter: cthelper: add missing attribute validation for cthelper Add missing attribute validation for cthelper to the netlink policy. Fixes: 12f7a505331e ("netfilter: add user-space connection tracking helper infrastructure") Signed-off-by: Jakub Kicinski Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nfnetlink_cthelper.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c index de3a9596b7f1b..a5f294aa8e4cf 100644 --- a/net/netfilter/nfnetlink_cthelper.c +++ b/net/netfilter/nfnetlink_cthelper.c @@ -742,6 +742,8 @@ static const struct nla_policy nfnl_cthelper_policy[NFCTH_MAX+1] = { [NFCTH_NAME] = { .type = NLA_NUL_STRING, .len = NF_CT_HELPER_NAME_LEN-1 }, [NFCTH_QUEUE_NUM] = { .type = NLA_U32, }, + [NFCTH_PRIV_DATA_LEN] = { .type = NLA_U32, }, + [NFCTH_STATUS] = { .type = NLA_U32, }, }; static const struct nfnl_callback nfnl_cthelper_cb[NFNL_MSG_CTHELPER_MAX] = { From 9d6effb2f1523eb84516e44213c00f2fd9e6afff Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 2 Mar 2020 21:08:32 -0800 Subject: [PATCH 07/11] netfilter: nft_payload: add missing attribute validation for payload csum flags Add missing attribute validation for NFTA_PAYLOAD_CSUM_FLAGS to the netlink policy. Fixes: 1814096980bb ("netfilter: nft_payload: layer 4 checksum adjustment for pseudoheader fields") Signed-off-by: Jakub Kicinski Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_payload.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index 1993af3a29795..a7de3a58f553d 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -129,6 +129,7 @@ static const struct nla_policy nft_payload_policy[NFTA_PAYLOAD_MAX + 1] = { [NFTA_PAYLOAD_LEN] = { .type = NLA_U32 }, [NFTA_PAYLOAD_CSUM_TYPE] = { .type = NLA_U32 }, [NFTA_PAYLOAD_CSUM_OFFSET] = { .type = NLA_U32 }, + [NFTA_PAYLOAD_CSUM_FLAGS] = { .type = NLA_U32 }, }; static int nft_payload_init(const struct nft_ctx *ctx, From 88a637719a1570705c02cacb3297af164b1714e7 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 2 Mar 2020 21:08:33 -0800 Subject: [PATCH 08/11] netfilter: nft_tunnel: add missing attribute validation for tunnels Add missing attribute validation for tunnel source and destination ports to the netlink policy. Fixes: af308b94a2a4 ("netfilter: nf_tables: add tunnel support") Signed-off-by: Jakub Kicinski Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_tunnel.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/netfilter/nft_tunnel.c b/net/netfilter/nft_tunnel.c index 4c3f2e24c7cba..764e88682a81f 100644 --- a/net/netfilter/nft_tunnel.c +++ b/net/netfilter/nft_tunnel.c @@ -339,6 +339,8 @@ static const struct nla_policy nft_tunnel_key_policy[NFTA_TUNNEL_KEY_MAX + 1] = [NFTA_TUNNEL_KEY_FLAGS] = { .type = NLA_U32, }, [NFTA_TUNNEL_KEY_TOS] = { .type = NLA_U8, }, [NFTA_TUNNEL_KEY_TTL] = { .type = NLA_U8, }, + [NFTA_TUNNEL_KEY_SPORT] = { .type = NLA_U16, }, + [NFTA_TUNNEL_KEY_DPORT] = { .type = NLA_U16, }, [NFTA_TUNNEL_KEY_OPTS] = { .type = NLA_NESTED, }, }; From d78008de6103c708171baff9650a7862645d23b0 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 3 Mar 2020 15:02:45 +0100 Subject: [PATCH 09/11] netfilter: nf_tables: dump NFTA_CHAIN_FLAGS attribute Missing NFTA_CHAIN_FLAGS netlink attribute when dumping basechain definitions. Fixes: c9626a2cbdb2 ("netfilter: nf_tables: add hardware offload support") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index bb064aa4154b4..f9e60981bd361 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1405,6 +1405,11 @@ static int nf_tables_fill_chain_info(struct sk_buff *skb, struct net *net, lockdep_commit_lock_is_held(net)); if (nft_dump_stats(skb, stats)) goto nla_put_failure; + + if ((chain->flags & NFT_CHAIN_HW_OFFLOAD) && + nla_put_be32(skb, NFTA_CHAIN_FLAGS, + htonl(NFT_CHAIN_HW_OFFLOAD))) + goto nla_put_failure; } if (nla_put_be32(skb, NFTA_CHAIN_USE, htonl(chain->use))) From 1d305ba40eb8081ff21eeb8ca6ba5c70fd920934 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 5 Mar 2020 11:15:36 +0100 Subject: [PATCH 10/11] netfilter: nf_tables: fix infinite loop when expr is not available nft will loop forever if the kernel doesn't support an expression: 1. nft_expr_type_get() appends the family specific name to the module list. 2. -EAGAIN is returned to nfnetlink, nfnetlink calls abort path. 3. abort path sets ->done to true and calls request_module for the expression. 4. nfnetlink replays the batch, we end up in nft_expr_type_get() again. 5. nft_expr_type_get attempts to append family-specific name. This one already exists on the list, so we continue 6. nft_expr_type_get adds the generic expression name to the module list. -EAGAIN is returned, nfnetlink calls abort path. 7. abort path encounters the family-specific expression which has 'done' set, so it gets removed. 8. abort path requests the generic expression name, sets done to true. 9. batch is replayed. If the expression could not be loaded, then we will end up back at 1), because the family-specific name got removed and the cycle starts again. Note that userspace can SIGKILL the nft process to stop the cycle, but the desired behaviour is to return an error after the generic expr name fails to load the expression. Fixes: eb014de4fd418 ("netfilter: nf_tables: autoload modules from the abort path") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index f9e60981bd361..38c680f28f157 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7388,13 +7388,8 @@ static void nf_tables_module_autoload(struct net *net) list_splice_init(&net->nft.module_list, &module_list); mutex_unlock(&net->nft.commit_mutex); list_for_each_entry_safe(req, next, &module_list, list) { - if (req->done) { - list_del(&req->list); - kfree(req); - } else { - request_module("%s", req->module); - req->done = true; - } + request_module("%s", req->module); + req->done = true; } mutex_lock(&net->nft.commit_mutex); list_splice(&module_list, &net->nft.module_list); @@ -8177,6 +8172,7 @@ static void __net_exit nf_tables_exit_net(struct net *net) __nft_release_tables(net); mutex_unlock(&net->nft.commit_mutex); WARN_ON_ONCE(!list_empty(&net->nft.tables)); + WARN_ON_ONCE(!list_empty(&net->nft.module_list)); } static struct pernet_operations nf_tables_net_ops = { From 6a42cefb25d8bdc1b391f4a53c78c32164eea2dd Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Fri, 6 Mar 2020 17:37:28 +0100 Subject: [PATCH 11/11] netfilter: nft_chain_nat: inet family is missing module ownership Set owner to THIS_MODULE, otherwise the nft_chain_nat module might be removed while there are still inet/nat chains in place. [ 117.942096] BUG: unable to handle page fault for address: ffffffffa0d5e040 [ 117.942101] #PF: supervisor read access in kernel mode [ 117.942103] #PF: error_code(0x0000) - not-present page [ 117.942106] PGD 200c067 P4D 200c067 PUD 200d063 PMD 3dc909067 PTE 0 [ 117.942113] Oops: 0000 [#1] PREEMPT SMP PTI [ 117.942118] CPU: 3 PID: 27 Comm: kworker/3:0 Not tainted 5.6.0-rc3+ #348 [ 117.942133] Workqueue: events nf_tables_trans_destroy_work [nf_tables] [ 117.942145] RIP: 0010:nf_tables_chain_destroy.isra.0+0x94/0x15a [nf_tables] [ 117.942149] Code: f6 45 54 01 0f 84 d1 00 00 00 80 3b 05 74 44 48 8b 75 e8 48 c7 c7 72 be de a0 e8 56 e6 2d e0 48 8b 45 e8 48 c7 c7 7f be de a0 <48> 8b 30 e8 43 e6 2d e0 48 8b 45 e8 48 8b 40 10 48 85 c0 74 5b 8b [ 117.942152] RSP: 0018:ffffc9000015be10 EFLAGS: 00010292 [ 117.942155] RAX: ffffffffa0d5e040 RBX: ffff88840be87fc2 RCX: 0000000000000007 [ 117.942158] RDX: 0000000000000007 RSI: 0000000000000086 RDI: ffffffffa0debe7f [ 117.942160] RBP: ffff888403b54b50 R08: 0000000000001482 R09: 0000000000000004 [ 117.942162] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8883eda7e540 [ 117.942164] R13: dead000000000122 R14: dead000000000100 R15: ffff888403b3db80 [ 117.942167] FS: 0000000000000000(0000) GS:ffff88840e4c0000(0000) knlGS:0000000000000000 [ 117.942169] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 117.942172] CR2: ffffffffa0d5e040 CR3: 00000003e4c52002 CR4: 00000000001606e0 [ 117.942174] Call Trace: [ 117.942188] nf_tables_trans_destroy_work.cold+0xd/0x12 [nf_tables] [ 117.942196] process_one_work+0x1d6/0x3b0 [ 117.942200] worker_thread+0x45/0x3c0 [ 117.942203] ? process_one_work+0x3b0/0x3b0 [ 117.942210] kthread+0x112/0x130 [ 117.942214] ? kthread_create_worker_on_cpu+0x40/0x40 [ 117.942221] ret_from_fork+0x35/0x40 nf_tables_chain_destroy() crashes on module_put() because the module is gone. Fixes: d164385ec572 ("netfilter: nat: add inet family nat support") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_chain_nat.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/netfilter/nft_chain_nat.c b/net/netfilter/nft_chain_nat.c index ff9ac8ae0031f..eac4a901233f2 100644 --- a/net/netfilter/nft_chain_nat.c +++ b/net/netfilter/nft_chain_nat.c @@ -89,6 +89,7 @@ static const struct nft_chain_type nft_chain_nat_inet = { .name = "nat", .type = NFT_CHAIN_T_NAT, .family = NFPROTO_INET, + .owner = THIS_MODULE, .hook_mask = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN) | (1 << NF_INET_LOCAL_OUT) |