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,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 8F930C433DF for ; Fri, 19 Jun 2020 15:12:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5FC3021582 for ; Fri, 19 Jun 2020 15:12:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592579522; bh=wJyh5j0fx3dTdY/TvsFuOEKeXxSb+H8xonC0coZh0V0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=M0tj85lYsk8XsTE6JXB+kDMo3TtAJNYMmGl5yBJZuIbb56F3o5wA29PhfCRkL0hti 6hZm6z7zKqo/NiZybEGcOA2csFrFyEzeKnqTMGlZdcQ9zul5rGO9ElR56HIUzBlfdW 5xp37+MUlL0kFi/K9lv/wrK/v0Xw2ZAdPVzWAEh4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391749AbgFSPMA (ORCPT ); Fri, 19 Jun 2020 11:12:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:42216 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2403853AbgFSPLs (ORCPT ); Fri, 19 Jun 2020 11:11:48 -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 BBC9E2158C; Fri, 19 Jun 2020 15:11:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592579507; bh=wJyh5j0fx3dTdY/TvsFuOEKeXxSb+H8xonC0coZh0V0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eEer/xEJph/n1jGsK6dev0bTBhbtsUGFodnBuOCZfECvSd+u+ZPRiFkYWaicwC6cw nz8z0xkwMjR5Pwv3cl12zDXzIrXCHx1gZJXGza4uwU4dCCvWV3E+2gQYRZKCiSkxP8 pW3Z6T69Q5eCWE+44clRiGPmmJXdA612LbAlhROU= 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 5.4 154/261] bpf: Fix map permissions check Date: Fri, 19 Jun 2020 16:32:45 +0200 Message-Id: <20200619141657.254727951@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141649.878808811@linuxfoundation.org> References: <20200619141649.878808811@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: 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 946cfdd3b2cc..e7af1ac69d75 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1118,7 +1118,8 @@ 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