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,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 22380C433E0 for ; Tue, 9 Jun 2020 00:01:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E001F2074B for ; Tue, 9 Jun 2020 00:01:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591660879; bh=wJyh5j0fx3dTdY/TvsFuOEKeXxSb+H8xonC0coZh0V0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=WR0KnRTSupf7OH/HCITacIrUeLnydz42uS/l1lJs96b40UZ7FaD4S+37otkubahHr 7t8urc3kkDQtROdulroWByVDzcPh/CyVp4JGP2XcCzFZfUTGBzJJLk/Umqfz+u2jyq sKrFscv/ID5KLs+SpIFj9hCEgYldbOaSCyOVLigE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387432AbgFIABR (ORCPT ); Mon, 8 Jun 2020 20:01:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:47082 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730946AbgFHXW2 (ORCPT ); Mon, 8 Jun 2020 19:22:28 -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 A9F1E208B8; Mon, 8 Jun 2020 23:22:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591658548; bh=wJyh5j0fx3dTdY/TvsFuOEKeXxSb+H8xonC0coZh0V0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ywm0/pZwDZcF+0gSsWQd2lp21yqA9KL/sqOgacny5NDQYwTZdtndliWpLCB1iqptj OuzHMDtTeGa7zJr/UlApwL2mhEj3UNIpArL+rbUMrsyXs5FaL736ZO6lfaJHnmA5NJ MbbNPFlNFpI7xe5iJguvW+jRBkVTb596sso5kPw8= 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 5.4 169/175] bpf: Fix map permissions check Date: Mon, 8 Jun 2020 19:18:42 -0400 Message-Id: <20200608231848.3366970-169-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200608231848.3366970-1-sashal@kernel.org> References: <20200608231848.3366970-1-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 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