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 36546C433E1 for ; Fri, 19 Jun 2020 15:42:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0A10120809 for ; Fri, 19 Jun 2020 15:42:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592581355; bh=U+JU3pulcrPnDSUFMUHuppeZgdml6VTYsuEf4BfNm28=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=oWcgHRdUQXTxtZXE+Iv4Gm9jmsA2h7Kp/oFSmfD88vzAjgkbBe4ov9t0pGsArqqUc Mq9b/MTq6Honh8wUX7RPoPdD7uTX5oTb/6oeo0VPASzZW3GKnhsJNy3eZFU2qN34ef 9cGFBcJQ5jmdaVmbATJ5iAAazfUOE6ZDGA9l/e+4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394022AbgFSPmd (ORCPT ); Fri, 19 Jun 2020 11:42:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:60370 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393633AbgFSP2e (ORCPT ); Fri, 19 Jun 2020 11:28:34 -0400 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 4112821919; Fri, 19 Jun 2020 15:28:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592580513; bh=U+JU3pulcrPnDSUFMUHuppeZgdml6VTYsuEf4BfNm28=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D5h4+87wGtENue0bBu6lzsTZl9CiW1yewL0XLTvTNFPF1q9xIxMbWift8Sm5qduYa uKBRiJEZD0DqDuZSJ563RCCeorAdQA0vMQfkN/xMf/jcixGHrxgGOahdgDVOpQuKr7 2H7cLvtITBv26JmOsFOIOxoMdfQkejBfVNCZTM9w= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anton Protopopov , Daniel Borkmann , Alexei Starovoitov , Sasha Levin Subject: [PATCH 5.7 248/376] bpf: Fix map permissions check Date: Fri, 19 Jun 2020 16:32:46 +0200 Message-Id: <20200619141722.065296471@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141710.350494719@linuxfoundation.org> References: <20200619141710.350494719@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Anton Protopopov [ Upstream commit 1ea0f9120c8ce105ca181b070561df5cbd6bc049 ] The map_lookup_and_delete_elem() function should check for both FMODE_CAN_WRITE and FMODE_CAN_READ permissions because it returns a map element to user space. Fixes: bd513cd08f10 ("bpf: add MAP_LOOKUP_AND_DELETE_ELEM syscall") Signed-off-by: Anton Protopopov Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200527185700.14658-5-a.s.protopopov@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- kernel/bpf/syscall.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 4e6dee19a668..5e52765161f9 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1468,7 +1468,8 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr) map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); - if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { + if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || + !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { err = -EPERM; goto err_put; } -- 2.25.1