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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 3D538C636CB for ; Thu, 15 Jul 2021 19:02:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22EC0613FC for ; Thu, 15 Jul 2021 19:02:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239806AbhGOTFF (ORCPT ); Thu, 15 Jul 2021 15:05:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:38430 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242937AbhGOTC1 (ORCPT ); Thu, 15 Jul 2021 15:02:27 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 99ABE613DA; Thu, 15 Jul 2021 18:58:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626375539; bh=9oZV2sweLG7QNjxJq5lidgr3AufUJfafWyGDoLTwjao=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LTF6kqcP85/9BTI16Ypnd1KfNeUuRlE+1+WQbf6ps5cVRct0Q6mQsQm67r6g05ogC bWUAanPGvC986TH9gYyQdfLJwCZy/oEugiGYWaXeaaouGMixG9CjtfsTMD33SoTypQ yUqUiTqoK3Rl1HBK1cmow9c/hLx7Onpr/u0LsDl4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sean Young , Daniel Borkmann , Sasha Levin Subject: [PATCH 5.12 131/242] media, bpf: Do not copy more entries than user space requested Date: Thu, 15 Jul 2021 20:38:13 +0200 Message-Id: <20210715182616.090328656@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210715182551.731989182@linuxfoundation.org> References: <20210715182551.731989182@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sean Young [ Upstream commit 647d446d66e493d23ca1047fa8492b0269674530 ] The syscall bpf(BPF_PROG_QUERY, &attr) should use the prog_cnt field to see how many entries user space provided and return ENOSPC if there are more programs than that. Before this patch, this is not checked and ENOSPC is never returned. Note that one lirc device is limited to 64 bpf programs, and user space I'm aware of -- ir-keytable -- always gives enough space for 64 entries already. However, we should not copy program ids than are requested. Signed-off-by: Sean Young Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20210623213754.632-1-sean@mess.org Signed-off-by: Sasha Levin --- drivers/media/rc/bpf-lirc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/media/rc/bpf-lirc.c b/drivers/media/rc/bpf-lirc.c index 3fe3edd80876..afae0afe3f81 100644 --- a/drivers/media/rc/bpf-lirc.c +++ b/drivers/media/rc/bpf-lirc.c @@ -326,7 +326,8 @@ int lirc_prog_query(const union bpf_attr *attr, union bpf_attr __user *uattr) } if (attr->query.prog_cnt != 0 && prog_ids && cnt) - ret = bpf_prog_array_copy_to_user(progs, prog_ids, cnt); + ret = bpf_prog_array_copy_to_user(progs, prog_ids, + attr->query.prog_cnt); unlock: mutex_unlock(&ir_raw_handler_lock); -- 2.30.2