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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 BA16EC35641 for ; Fri, 21 Feb 2020 08:01:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 877D324673 for ; Fri, 21 Feb 2020 08:01:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582272064; bh=mKJXdC1spszpUhOmwpzsp8VjgJ+xnq6JmhBX2kjg/Cs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=pE9ID+lh9PwncuUC6hDu/MLKN9eVVT3lmT02digSrYkmABqF9CZVS0Lklh6d3wrnf 1gQJJoGeh1z6Y+jC8sZR/fHVtPDeuAddWKFlmLx4nwWM0rwbu/mPcUrYbVBeMjlCLV xXLR9nqFF5zrIcoxNi5yNva9IMXMyvPOENBdWzUI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731153AbgBUIBD (ORCPT ); Fri, 21 Feb 2020 03:01:03 -0500 Received: from mail.kernel.org ([198.145.29.99]:33254 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731142AbgBUIBA (ORCPT ); Fri, 21 Feb 2020 03:01:00 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E8E2D2073A; Fri, 21 Feb 2020 08:00:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582272059; bh=mKJXdC1spszpUhOmwpzsp8VjgJ+xnq6JmhBX2kjg/Cs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UvVnbCCKKWA+54eRtau/wQAK7ot3CI/L6cT9e16Yk2dMOqX0XsBlfxLQ8Cc3OYdRl YwdEGCtss+BFLBQ1mF+VDt5vPnY8/oJC3QzhcLMrpg44Peh5Lw7ERCMfao/zEcuz6j xGmV3Z1xKalgZyvTrRyyz6mv4XxguE3BjUw3SLEc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vasily Averin , Daniel Borkmann , Sasha Levin Subject: [PATCH 5.5 353/399] bpf: map_seq_next should always increase position index Date: Fri, 21 Feb 2020 08:41:18 +0100 Message-Id: <20200221072435.276879379@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200221072402.315346745@linuxfoundation.org> References: <20200221072402.315346745@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 ecf42bec38c00..6f22e0e74ef24 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -196,6 +196,7 @@ 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; @@ -208,8 +209,6 @@ 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