From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 223FFC43464 for ; Fri, 18 Sep 2020 02:49:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1F4323444 for ; Fri, 18 Sep 2020 02:49:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600397380; bh=SgnL6lV3WEABDJJLLTBkyo4xD4dIVj3iRHnI1tAuXnA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=hZDmIvg4WaHVkWXjCwS6+ePS/ohen0Vua7mssfKbVC8kHdReCqfDlDx0lRAz6ShgG fwdxZNrWZ673CZmWVScG2LDHzJ5Id3LF62Zf4P0WXPsH7xfZiQGS0uFm5yCNRbCT56 /f53ofhyGZK68zF7jGMkEvg+UJbZv/EkoxSN+wz8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728200AbgIRCJB (ORCPT ); Thu, 17 Sep 2020 22:09:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:60550 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728195AbgIRCI4 (ORCPT ); Thu, 17 Sep 2020 22:08:56 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 136C623770; Fri, 18 Sep 2020 02:08:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600394935; bh=SgnL6lV3WEABDJJLLTBkyo4xD4dIVj3iRHnI1tAuXnA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tq6miZgOxZFQApIR5K4ifyTzOjpXgPBKDI57fhRKNC65cj+l2hL4M4wUtjkOXtqWh 0aWQ0VMH6Rj4VSnGY+KEt7O9/n0vvcihWbBTaeyhQ0idFRxyG1tAmyIR6UeuphIgAg 4JCLbr4KYcxCd/cNEjfN80E4SG286kigqJuBxvq0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vasily Averin , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 045/206] ipv6_route_seq_next should increase position index Date: Thu, 17 Sep 2020 22:05:21 -0400 Message-Id: <20200918020802.2065198-45-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200918020802.2065198-1-sashal@kernel.org> References: <20200918020802.2065198-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Vasily Averin [ Upstream commit 4fc427e0515811250647d44de38d87d7b0e0790f ] if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv6/ip6_fib.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index 5e8979c1f76d8..28b51f4aa6418 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -2372,14 +2372,13 @@ static void *ipv6_route_seq_next(struct seq_file *seq, void *v, loff_t *pos) struct net *net = seq_file_net(seq); struct ipv6_route_iter *iter = seq->private; + ++(*pos); if (!v) goto iter_table; n = rcu_dereference_bh(((struct fib6_info *)v)->fib6_next); - if (n) { - ++*pos; + if (n) return n; - } iter_table: ipv6_route_check_sernum(iter); @@ -2387,8 +2386,6 @@ iter_table: r = fib6_walk_continue(&iter->w); spin_unlock_bh(&iter->tbl->tb6_lock); if (r > 0) { - if (v) - ++*pos; return iter->w.leaf; } else if (r < 0) { fib6_walker_unlink(net, &iter->w); -- 2.25.1