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=ham 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 C551DC35640 for ; Fri, 21 Feb 2020 08:14:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 91BE124672 for ; Fri, 21 Feb 2020 08:14:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582272868; bh=kxTg842rKPYYI0+Z1PfQ8eFsHAo/dHjWgz+J9Sx9eRU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BRMxm50FJ7x/l2YVoc1cqfGyhE/9N7kYCXWgp4c9UwFXlM+Zr6NfMySXSnG6xNw8D zAFbG2o3mz06aQnrKQtf28Xf5tVfFb1Pi3xgzDQ08Nkwngh+rPSPisszYylVZ5aGnE tHFBgjEem/FC2OKlk4LkfiM2ifk0kc3KiClJQFKQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733188AbgBUIO1 (ORCPT ); Fri, 21 Feb 2020 03:14:27 -0500 Received: from mail.kernel.org ([198.145.29.99]:50904 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732548AbgBUIO0 (ORCPT ); Fri, 21 Feb 2020 03:14:26 -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 BB07C20578; Fri, 21 Feb 2020 08:14:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582272866; bh=kxTg842rKPYYI0+Z1PfQ8eFsHAo/dHjWgz+J9Sx9eRU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vxEZY6C3boTiS0OljzWOk/lhNSDzsRlU/GPlMrXjDerdD3lLuLOxREaeCnkWU14UG nVI3kgoBMozn5KeafymtjWJ+nT6FRBNmd4qtvVt9kgry5IQcUY7gtu8pWljwcSOf8k rlAdSCN6jLlKkptPRStXyFcvW3L/VRHa+mGmWLTg= 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 5.4 305/344] bpf: map_seq_next should always increase position index Date: Fri, 21 Feb 2020 08:41:44 +0100 Message-Id: <20200221072417.619752452@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200221072349.335551332@linuxfoundation.org> References: <20200221072349.335551332@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 a70f7209cda3f..218c09ff6a273 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