From 6c1f9f1b6eda0b4f26a752f4f9c4c57aa4fa730c Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Wed, 29 May 2024 19:50:41 +0800 Subject: [PATCH] netfilter: nf_tables: reject new basechain after table flag update stable inclusion from stable-v5.10.215 commit 7b6fba6918714afee3e17796113ccab636255c7b category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9QG4V CVE: CVE-2024-35900 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=7b6fba6918714afee3e17796113ccab636255c7b -------------------------------- commit 994209ddf4f430946f6247616b2e33d179243769 upstream. When dormant flag is toggled, hooks are disabled in the commit phase by iterating over current chains in table (existing and new). The following configuration allows for an inconsistent state: add table x add chain x y { type filter hook input priority 0; } add table x { flags dormant; } add chain x w { type filter hook input priority 1; } which triggers the following warning when trying to unregister chain w which is already unregistered. [ 127.322252] WARNING: CPU: 7 PID: 1211 at net/netfilter/core.c:50 1 __nf_unregister_net_hook+0x21a/0x260 [...] [ 127.322519] Call Trace: [ 127.322521] [ 127.322524] ? __warn+0x9f/0x1a0 [ 127.322531] ? __nf_unregister_net_hook+0x21a/0x260 [ 127.322537] ? report_bug+0x1b1/0x1e0 [ 127.322545] ? handle_bug+0x3c/0x70 [ 127.322552] ? exc_invalid_op+0x17/0x40 [ 127.322556] ? asm_exc_invalid_op+0x1a/0x20 [ 127.322563] ? kasan_save_free_info+0x3b/0x60 [ 127.322570] ? __nf_unregister_net_hook+0x6a/0x260 [ 127.322577] ? __nf_unregister_net_hook+0x21a/0x260 [ 127.322583] ? __nf_unregister_net_hook+0x6a/0x260 [ 127.322590] ? __nf_tables_unregister_hook+0x8a/0xe0 [nf_tables] [ 127.322655] nft_table_disable+0x75/0xf0 [nf_tables] [ 127.322717] nf_tables_commit+0x2571/0x2620 [nf_tables] Fixes: 179d9ba5559a ("netfilter: nf_tables: fix table flag updates") Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman Signed-off-by: Zhengchao Shao --- net/netfilter/nf_tables_api.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index e11a1cad0763..31bc82998d42 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2242,6 +2242,9 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask, struct nft_stats __percpu *stats = NULL; struct nft_chain_hook hook; + if (table->flags & __NFT_TABLE_F_UPDATE) + return -EINVAL; + if (flags & NFT_CHAIN_BINDING) return -EOPNOTSUPP; -- Gitee