From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 079BF535FBB; Wed, 23 Sep 2026 14:39:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790174375; cv=none; b=OVoNfK36Ck3jxmdiiQs2CRF0fK3avXVnLyZ3Z9QxcqFE88BVXMLAHHH7T6qdbw02NP5GkVrPUhp5WJpWiEdNQh6aTGRaZMJ/StUWkA8k43sJ4beH4T+BM3MsqGdDQAlrJVX4sZXGpUbU/fVC+siexgGxBLS1SZ/LSCND0lhHj9w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790174375; c=relaxed/simple; bh=bakQTiDcdVnux9rtYqBwizQb61QE+kS2uljXLkcUqj4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sG7n8kAhZUXJWxKytAr1RgIf5GXqvD1zcEmxzXA3Fhopzfhnhq3yae38uSREyj0XKhzJ2rkplCN4n8sjVdcVKJS3aOFYP/1c+gnLtWYQpc6twCz2i+xgp0gSIhDDQ9rpvbcHQWYofyjD4VRDzVyVHmtRcEavefHG27K6KWQuQVM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ULngKkvy; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ULngKkvy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 588121F000FF; Wed, 23 Sep 2026 14:39:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790174373; bh=6dt7DpmBFHMK9aPXJf7YEY2k4Ce2KL6Td3zzs7K6gTw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ULngKkvyw3EjjfQVF7KTDXnE/TajBFHNiYouziyqEvPAR77BEDFw6Ng6OUsNPMPx8 QtXvkLF6XFW2eBNzrIaW8fC3LIeG7MulHSpl4z2Wu7b2GE6LlA6bsZdmlp0ZeDiuJm er7GZofCZafcmvV7RVl5YQiZs6KCPqDF0J/dp0Gs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Wei Fang , Fernando Fernandez Mancera , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 6.18 093/398] netfilter: nf_tables: fix device name and prefix match in hook lookup Date: Wed, 23 Sep 2026 16:02:47 +0200 Message-ID: <20260923140645.849734859@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140643.441954610@linuxfoundation.org> References: <20260923140643.441954610@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Fernando Fernandez Mancera [ Upstream commit 444e4c88c9c62a3d823069006563513fe7d5aa66 ] Currently, a netdev chain or flowtable hooked to a device prefix can be unintentionally deleted by a control-plane request targeting an exact device name or even a shorter one due to the usage of min() to calculate the length to match. Fix this by making sure an exact device match never matches a prefix and that both the target and the candidate have the same length during delete operation. The add and update paths retain the existing overlap matching to prevent a single device from matching multiple hooks. Reported-by: Wei Fang Closes: https://lore.kernel.org/netfilter-devel/CANE+tVrDeNCHQVmsqkV2ozeBqyE3GtRDMhZgsg1bhw10yGNTRQ@mail.gmail.com/ Fixes: 6d07a289504a ("netfilter: nf_tables: Support wildcard netdev hook specs") Signed-off-by: Fernando Fernandez Mancera Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nf_tables_api.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index a3a66b6268cd6..321a0dd92178b 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2343,11 +2343,14 @@ static struct nft_hook *nft_netdev_hook_alloc(struct net *net, } static struct nft_hook *nft_hook_list_find(struct list_head *hook_list, - const struct nft_hook *this) + const struct nft_hook *this, + bool strict) { struct nft_hook *hook; list_for_each_entry(hook, hook_list, list) { + if (strict && hook->ifnamelen != this->ifnamelen) + continue; if (!strncmp(hook->ifname, this->ifname, min(hook->ifnamelen, this->ifnamelen))) return hook; @@ -2385,7 +2388,7 @@ static int nf_tables_parse_netdev_hooks(struct net *net, err = PTR_ERR(hook); goto err_hook; } - if (nft_hook_list_find(hook_list, hook)) { + if (nft_hook_list_find(hook_list, hook, false)) { NL_SET_BAD_ATTR(extack, tmp); nft_netdev_hook_free(hook); err = -EEXIST; @@ -2842,7 +2845,7 @@ static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy, ops->hook = basechain->ops.hook; } - if (nft_hook_list_find(&basechain->hook_list, h)) { + if (nft_hook_list_find(&basechain->hook_list, h, false)) { list_del(&h->list); nft_netdev_hook_free(h); continue; @@ -2855,7 +2858,8 @@ static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy, !nft_trans_chain_update(trans)) continue; - if (nft_hook_list_find(&nft_trans_chain_hooks(trans), h)) { + if (nft_hook_list_find(&nft_trans_chain_hooks(trans), + h, false)) { nft_chain_release_hook(&hook); return -EEXIST; } @@ -3130,7 +3134,7 @@ static int nft_delchain_hook(struct nft_ctx *ctx, return err; list_for_each_entry(this, &chain_hook.list, list) { - hook = nft_hook_list_find(&basechain->hook_list, this); + hook = nft_hook_list_find(&basechain->hook_list, this, true); if (!hook) { err = -ENOENT; goto err_chain_del_hook; @@ -8921,7 +8925,7 @@ static int nft_register_flowtable_net_hooks(struct net *net, if (!nft_is_active_next(net, ft)) continue; - if (nft_hook_list_find(&ft->hook_list, hook)) { + if (nft_hook_list_find(&ft->hook_list, hook, false)) { err = -EEXIST; goto err_unregister_net_hooks; } @@ -8980,7 +8984,7 @@ static int nft_flowtable_update(struct nft_ctx *ctx, const struct nlmsghdr *nlh, return err; list_for_each_entry_safe(hook, next, &flowtable_hook.list, list) { - if (nft_hook_list_find(&flowtable->hook_list, hook)) { + if (nft_hook_list_find(&flowtable->hook_list, hook, false)) { list_del(&hook->list); nft_netdev_hook_free(hook); continue; @@ -8993,7 +8997,7 @@ static int nft_flowtable_update(struct nft_ctx *ctx, const struct nlmsghdr *nlh, !nft_trans_flowtable_update(trans)) continue; - if (nft_hook_list_find(&nft_trans_flowtable_hooks(trans), hook)) { + if (nft_hook_list_find(&nft_trans_flowtable_hooks(trans), hook, false)) { err = -EEXIST; goto err_flowtable_update_hook; } @@ -9213,7 +9217,7 @@ static int nft_delflowtable_hook(struct nft_ctx *ctx, return err; list_for_each_entry(this, &flowtable_hook.list, list) { - hook = nft_hook_list_find(&flowtable->hook_list, this); + hook = nft_hook_list_find(&flowtable->hook_list, this, true); if (!hook) { err = -ENOENT; goto err_flowtable_del_hook; -- 2.53.0