From 76b907ee00c4a5cdd5d0adbacdaa1c1989385615 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Fri, 9 Sep 2022 12:42:11 +0200 Subject: [PATCH 1/5] netfilter: conntrack: remove nf_conntrack_helper documentation This toggle has been already remove by b118509076b3 ("netfilter: remove nf_conntrack_helper sysctl and modparam toggles"). Remove the documentation entry for this toggle too. Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- Documentation/networking/nf_conntrack-sysctl.rst | 9 --------- 1 file changed, 9 deletions(-) diff --git a/Documentation/networking/nf_conntrack-sysctl.rst b/Documentation/networking/nf_conntrack-sysctl.rst index 834945ebc4cdf..1120d71f28d7b 100644 --- a/Documentation/networking/nf_conntrack-sysctl.rst +++ b/Documentation/networking/nf_conntrack-sysctl.rst @@ -70,15 +70,6 @@ nf_conntrack_generic_timeout - INTEGER (seconds) Default for generic timeout. This refers to layer 4 unknown/unsupported protocols. -nf_conntrack_helper - BOOLEAN - - 0 - disabled (default) - - not 0 - enabled - - Enable automatic conntrack helper assignment. - If disabled it is required to set up iptables rules to assign - helpers to connections. See the CT target description in the - iptables-extensions(8) man page for further information. - nf_conntrack_icmp_timeout - INTEGER (seconds) default 30 From 921ebde3c0d22c8cba74ce8eb3cc4626abff1ccd Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Mon, 12 Sep 2022 21:41:00 +0900 Subject: [PATCH 2/5] netfilter: nf_tables: fix nft_counters_enabled underflow at nf_tables_addchain() syzbot is reporting underflow of nft_counters_enabled counter at nf_tables_addchain() [1], for commit 43eb8949cfdffa76 ("netfilter: nf_tables: do not leave chain stats enabled on error") missed that nf_tables_chain_destroy() after nft_basechain_init() in the error path of nf_tables_addchain() decrements the counter because nft_basechain_init() makes nft_is_base_chain() return true by setting NFT_CHAIN_BASE flag. Increment the counter immediately after returning from nft_basechain_init(). Link: https://syzkaller.appspot.com/bug?extid=b5d82a651b71cd8a75ab [1] Reported-by: syzbot Signed-off-by: Tetsuo Handa Tested-by: syzbot Fixes: 43eb8949cfdffa76 ("netfilter: nf_tables: do not leave chain stats enabled on error") Signed-off-by: Florian Westphal --- net/netfilter/nf_tables_api.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 816052089b336..e062754dc6ccb 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2197,7 +2197,6 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask, struct netlink_ext_ack *extack) { const struct nlattr * const *nla = ctx->nla; - struct nft_stats __percpu *stats = NULL; struct nft_table *table = ctx->table; struct nft_base_chain *basechain; struct net *net = ctx->net; @@ -2212,6 +2211,7 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask, return -EOVERFLOW; if (nla[NFTA_CHAIN_HOOK]) { + struct nft_stats __percpu *stats = NULL; struct nft_chain_hook hook; if (flags & NFT_CHAIN_BINDING) @@ -2245,6 +2245,8 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask, kfree(basechain); return err; } + if (stats) + static_branch_inc(&nft_counters_enabled); } else { if (flags & NFT_CHAIN_BASE) return -EINVAL; @@ -2319,9 +2321,6 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask, goto err_unregister_hook; } - if (stats) - static_branch_inc(&nft_counters_enabled); - table->use++; return 0; From 9a4d6dd554b86e65581ef6b6638a39ae079b17ac Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Mon, 12 Sep 2022 22:58:51 +0900 Subject: [PATCH 3/5] netfilter: nf_tables: fix percpu memory leak at nf_tables_addchain() It seems to me that percpu memory for chain stats started leaking since commit 3bc158f8d0330f0a ("netfilter: nf_tables: map basechain priority to hardware priority") when nft_chain_offload_priority() returned an error. Signed-off-by: Tetsuo Handa Fixes: 3bc158f8d0330f0a ("netfilter: nf_tables: map basechain priority to hardware priority") Signed-off-by: Florian Westphal --- net/netfilter/nf_tables_api.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index e062754dc6ccb..63c70141b3e5d 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2243,6 +2243,7 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask, if (err < 0) { nft_chain_release_hook(&hook); kfree(basechain); + free_percpu(stats); return err; } if (stats) From 62ce44c4fff947eebdf10bb582267e686e6835c9 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 20 Sep 2022 14:20:17 +0200 Subject: [PATCH 4/5] netfilter: ebtables: fix memory leak when blob is malformed The bug fix was incomplete, it "replaced" crash with a memory leak. The old code had an assignment to "ret" embedded into the conditional, restore this. Fixes: 7997eff82828 ("netfilter: ebtables: reject blobs that don't provide all entry points") Reported-and-tested-by: syzbot+a24c5252f3e3ab733464@syzkaller.appspotmail.com Signed-off-by: Florian Westphal --- net/bridge/netfilter/ebtables.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 9a0ae59cdc500..4f385d52a1c49 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1040,8 +1040,10 @@ static int do_replace_finish(struct net *net, struct ebt_replace *repl, goto free_iterate; } - if (repl->valid_hooks != t->valid_hooks) + if (repl->valid_hooks != t->valid_hooks) { + ret = -EINVAL; goto free_unlock; + } if (repl->num_counters && repl->num_counters != t->private->nentries) { ret = -EINVAL; From d25088932227680988a6b794221e031a7232f137 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 20 Sep 2022 18:31:30 +0200 Subject: [PATCH 5/5] netfilter: nf_ct_ftp: fix deadlock when nat rewrite is needed We can't use ct->lock, this is already used by the seqadj internals. When using ftp helper + nat, seqadj will attempt to acquire ct->lock again. Revert back to a global lock for now. Fixes: c783a29c7e59 ("netfilter: nf_ct_ftp: prefer skb_linearize") Reported-by: Bruno de Paula Larini Signed-off-by: Florian Westphal --- net/netfilter/nf_conntrack_ftp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nf_conntrack_ftp.c b/net/netfilter/nf_conntrack_ftp.c index 0d9332e9cf71a..617f744a2e3a3 100644 --- a/net/netfilter/nf_conntrack_ftp.c +++ b/net/netfilter/nf_conntrack_ftp.c @@ -33,6 +33,7 @@ MODULE_AUTHOR("Rusty Russell "); MODULE_DESCRIPTION("ftp connection tracking helper"); MODULE_ALIAS("ip_conntrack_ftp"); MODULE_ALIAS_NFCT_HELPER(HELPER_NAME); +static DEFINE_SPINLOCK(nf_ftp_lock); #define MAX_PORTS 8 static u_int16_t ports[MAX_PORTS]; @@ -409,7 +410,8 @@ static int help(struct sk_buff *skb, } datalen = skb->len - dataoff; - spin_lock_bh(&ct->lock); + /* seqadj (nat) uses ct->lock internally, nf_nat_ftp would cause deadlock */ + spin_lock_bh(&nf_ftp_lock); fb_ptr = skb->data + dataoff; ends_in_nl = (fb_ptr[datalen - 1] == '\n'); @@ -538,7 +540,7 @@ static int help(struct sk_buff *skb, if (ends_in_nl) update_nl_seq(ct, seq, ct_ftp_info, dir, skb); out: - spin_unlock_bh(&ct->lock); + spin_unlock_bh(&nf_ftp_lock); return ret; }