From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A391F2DF73; Mon, 8 Apr 2024 13:07:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712581665; cv=none; b=QZs64urGK8Dbmm4BZxtrFAyVkOTIYxqOoDDfJEwgH79loY3zJm3rgYr6STDDKCr+jYOFJxkDqss0AbbjQgdprfBaDGGnBuvdTykTFD9nwvc9sLSLztZyM7cJA8zgSD1iSujqKKoc6kwJup9Bab+i63jAM7RPVIWhufWlgFSgMi4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712581665; c=relaxed/simple; bh=kTS1yH+O4ga5knILrZ1annxfQcwEP7vkLcJCC+27ON4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bAt18flcevMVFXeTC4cTrsye0RV9cXu21XoEumFcJuQgAJaWVFkFVkXRWlQla5VKWzuBC6P+F6K+v28Xy+g29QOKoKMc8EKAYxAB18fOLI/P9QdplZK30OnnKJKfIP3XO/pyEZj8QGBsHgEqLZiUdkISoOAiEF0RKEa7Mo0uQ8w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=taUusbAk; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="taUusbAk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F2B6C433C7; Mon, 8 Apr 2024 13:07:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712581665; bh=kTS1yH+O4ga5knILrZ1annxfQcwEP7vkLcJCC+27ON4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=taUusbAkgMjmQhUVXlV74BVRCoujokjOhpAhx5S4p0cMIBIp5uFy0OQHU7I9k/DcL 26QP1ngO7735ncBmTJCBZHs3g/xG2/FV32+5oBVz/7DrlhK4D/YtUO/gdVPjsQppGy R9WTm7bdqJX+pXTFczeHO0WJ35l9wCJrxqMIwZ2k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ziyang Xuan , Pablo Neira Ayuso Subject: [PATCH 6.1 042/138] netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get() Date: Mon, 8 Apr 2024 14:57:36 +0200 Message-ID: <20240408125257.537747327@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125256.218368873@linuxfoundation.org> References: <20240408125256.218368873@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ziyang Xuan commit 24225011d81b471acc0e1e315b7d9905459a6304 upstream. nft_unregister_flowtable_type() within nf_flow_inet_module_exit() can concurrent with __nft_flowtable_type_get() within nf_tables_newflowtable(). And thhere is not any protection when iterate over nf_tables_flowtables list in __nft_flowtable_type_get(). Therefore, there is pertential data-race of nf_tables_flowtables list entry. Use list_for_each_entry_rcu() to iterate over nf_tables_flowtables list in __nft_flowtable_type_get(), and use rcu_read_lock() in the caller nft_flowtable_type_get() to protect the entire type query process. Fixes: 3b49e2e94e6e ("netfilter: nf_tables: add flow table netlink frontend") Signed-off-by: Ziyang Xuan Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/netfilter/nf_tables_api.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7841,11 +7841,12 @@ static int nft_flowtable_parse_hook(cons return err; } +/* call under rcu_read_lock */ static const struct nf_flowtable_type *__nft_flowtable_type_get(u8 family) { const struct nf_flowtable_type *type; - list_for_each_entry(type, &nf_tables_flowtables, list) { + list_for_each_entry_rcu(type, &nf_tables_flowtables, list) { if (family == type->family) return type; } @@ -7857,9 +7858,13 @@ nft_flowtable_type_get(struct net *net, { const struct nf_flowtable_type *type; + rcu_read_lock(); type = __nft_flowtable_type_get(family); - if (type != NULL && try_module_get(type->owner)) + if (type != NULL && try_module_get(type->owner)) { + rcu_read_unlock(); return type; + } + rcu_read_unlock(); lockdep_nfnl_nft_mutex_not_held(); #ifdef CONFIG_MODULES