From patchwork Mon Nov 21 18:26:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Felix Fietkau X-Patchwork-Id: 13051541 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C4CDC4332F for ; Mon, 21 Nov 2022 18:26:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229635AbiKUS04 (ORCPT ); Mon, 21 Nov 2022 13:26:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39094 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229913AbiKUS0k (ORCPT ); Mon, 21 Nov 2022 13:26:40 -0500 Received: from nbd.name (nbd.name [46.4.11.11]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 722E7D02D6; Mon, 21 Nov 2022 10:26:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=nbd.name; s=20160729; h=Content-Transfer-Encoding:MIME-Version:Message-Id:Date:Subject: Cc:To:From:Sender:Reply-To:Content-Type:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=Fz7dU5AsHIREf9gJ+3uHjaOYyC69u8wavjx25CmztKk=; b=bmtsOS4rDCd1b4M/f2CJG3mydH MrOT08YZbpgJcOoOZ2dXOODZKLejl3USMNmxKOHXYdBPjqb92gjbWzBZZnN+DOKX0PDZlO9fxjStf T5ZqmNr+vPvcR0V+7EtKn88L4iIublbw8fXn8P3rDt1hHhqcCnaDJPlwvIPSOjDsu16w=; Received: from p200300daa7225c007502151ad3a4cf6f.dip0.t-ipconnect.de ([2003:da:a722:5c00:7502:151a:d3a4:cf6f] helo=Maecks.lan) by ds12 with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 (Exim 4.94.2) (envelope-from ) id 1oxBUm-003YoF-LG; Mon, 21 Nov 2022 19:26:16 +0100 From: Felix Fietkau To: netfilter-devel@vger.kernel.org, Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: coreteam@netfilter.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] netfilter: nf_flow_table: add missing locking Date: Mon, 21 Nov 2022 19:26:15 +0100 Message-Id: <20221121182615.90843-1-nbd@nbd.name> X-Mailer: git-send-email 2.38.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org nf_flow_table_block_setup and the driver TC_SETUP_FT call can modify the flow block cb list while they are being traversed elsewhere, causing a crash. Add a write lock around the calls to protect readers Signed-off-by: Felix Fietkau Reported-by: Chad Monroe --- net/netfilter/nf_flow_table_offload.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/netfilter/nf_flow_table_offload.c b/net/netfilter/nf_flow_table_offload.c index b04645ced89b..00b522890d77 100644 --- a/net/netfilter/nf_flow_table_offload.c +++ b/net/netfilter/nf_flow_table_offload.c @@ -1098,6 +1098,7 @@ static int nf_flow_table_block_setup(struct nf_flowtable *flowtable, struct flow_block_cb *block_cb, *next; int err = 0; + down_write(&flowtable->flow_block_lock); switch (cmd) { case FLOW_BLOCK_BIND: list_splice(&bo->cb_list, &flowtable->flow_block.cb_list); @@ -1112,6 +1113,7 @@ static int nf_flow_table_block_setup(struct nf_flowtable *flowtable, WARN_ON_ONCE(1); err = -EOPNOTSUPP; } + up_write(&flowtable->flow_block_lock); return err; } @@ -1168,7 +1170,9 @@ static int nf_flow_table_offload_cmd(struct flow_block_offload *bo, nf_flow_table_block_offload_init(bo, dev_net(dev), cmd, flowtable, extack); + down_write(&flowtable->flow_block_lock); err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_FT, bo); + up_write(&flowtable->flow_block_lock); if (err < 0) return err;