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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 3C54CC2BA83 for ; Fri, 14 Feb 2020 17:00:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 086F12067D for ; Fri, 14 Feb 2020 17:00:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581699639; bh=7P2vlFybEQGvQnGZvdak6Xt5WNMRnhmHfVS2Glgdc78=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tMqfGLlw2SZCfeGQw2WFMe7btDSSw1/hAaQf2BoBwlAS0Kom9lXjo2yUNxHfXVoSZ YPpiDNtCpZcSyETFVbGLrpTgNZIH3ksEJaj2DXMyTGDN0tPu8Yt4K2c65PZ5o4FHtO W1Stu5JCeniCm8Aw95g90QFVBIaAs2cxTzxJjrOs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404286AbgBNQQf (ORCPT ); Fri, 14 Feb 2020 11:16:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:47392 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392616AbgBNQQd (ORCPT ); Fri, 14 Feb 2020 11:16:33 -0500 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 93C2524676; Fri, 14 Feb 2020 16:16:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581696992; bh=7P2vlFybEQGvQnGZvdak6Xt5WNMRnhmHfVS2Glgdc78=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cESJPItgrGwjm6V0ciDAxEe51wumZdjpHEpSzS8PiFrQRkN6SPV3CXgJJF5/GAYeh oYe/tj4iACRngHtA+qOSNBzU2KLbvAHmHashW6Z31bXAJ0Wb+AUl4ILQgJLCz0Nbjp G4gYKJ1NmnCEJ7Cr74ADiMKqvZ/yiun7qNVoXYhg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vasily Averin , Daniel Borkmann , Sasha Levin , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 226/252] bpf: map_seq_next should always increase position index Date: Fri, 14 Feb 2020 11:11:21 -0500 Message-Id: <20200214161147.15842-226-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214161147.15842-1-sashal@kernel.org> References: <20200214161147.15842-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Vasily Averin [ Upstream commit 90435a7891a2259b0f74c5a1bc5600d0d64cba8f ] If seq_file .next fuction does not change position index, read after some lseek can generate an unexpected output. See also: https://bugzilla.kernel.org/show_bug.cgi?id=206283 v1 -> v2: removed missed increment in end of function Signed-off-by: Vasily Averin Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/eca84fdd-c374-a154-d874-6c7b55fc3bc4@virtuozzo.com Signed-off-by: Sasha Levin --- kernel/bpf/inode.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index dc9d7ac8228db..c04815bb15cc1 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -198,6 +198,7 @@ static void *map_seq_next(struct seq_file *m, void *v, loff_t *pos) void *key = map_iter(m)->key; void *prev_key; + (*pos)++; if (map_iter(m)->done) return NULL; @@ -210,8 +211,6 @@ static void *map_seq_next(struct seq_file *m, void *v, loff_t *pos) map_iter(m)->done = true; return NULL; } - - ++(*pos); return key; } -- 2.20.1