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,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 E1044C433E0 for ; Tue, 9 Jun 2020 00:44:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B726C20737 for ; Tue, 9 Jun 2020 00:44:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591663479; bh=U+JU3pulcrPnDSUFMUHuppeZgdml6VTYsuEf4BfNm28=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1xQ0r13+hHTVSXdIZG9OLKW/mXcH4BLYDaDvOeCgD+a4wmw+CBVmxHyy+KsdgCCsC h5dZnrAKqXVctGs3cJIUpPw4+xgOl4F+q9Nc3yhdkQVV36xHPTSwchipGVHmn6EztY 2Nlr4KZnPZEN5/jdLo+QzuF03WIu3sniPEyTt5TA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729023AbgFHXL7 (ORCPT ); Mon, 8 Jun 2020 19:11:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:59044 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729013AbgFHXL4 (ORCPT ); Mon, 8 Jun 2020 19:11:56 -0400 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 CF45A2145D; Mon, 8 Jun 2020 23:11:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591657915; bh=U+JU3pulcrPnDSUFMUHuppeZgdml6VTYsuEf4BfNm28=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X0ltNQV0ghGRev4g5tC1lTwAVT+9MUdObSE7WIZnMHBqM4s+P6iOnezrhsGHM6MMX 2LIzPLXswrryB6FL3U2cRhf8l4W3eviauEXh+dtxsxNwSu06oi122K/aigQoG7unlq JZCUG7XR4gFBpuIC8qZuOIBaakQ3nZLtXEtQdH1U= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Anton Protopopov , Daniel Borkmann , Alexei Starovoitov , Sasha Levin , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 5.7 266/274] bpf: Fix map permissions check Date: Mon, 8 Jun 2020 19:05:59 -0400 Message-Id: <20200608230607.3361041-266-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200608230607.3361041-1-sashal@kernel.org> References: <20200608230607.3361041-1-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: 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