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=-13.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,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 56BE3C433ED for ; Tue, 18 May 2021 09:08:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31A256108D for ; Tue, 18 May 2021 09:08:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347908AbhERJJb (ORCPT ); Tue, 18 May 2021 05:09:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37618 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347736AbhERJIb (ORCPT ); Tue, 18 May 2021 05:08:31 -0400 Received: from mail-wr1-x42a.google.com (mail-wr1-x42a.google.com [IPv6:2a00:1450:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C7F6C061347 for ; Tue, 18 May 2021 02:07:13 -0700 (PDT) Received: by mail-wr1-x42a.google.com with SMTP id z17so9311268wrq.7 for ; Tue, 18 May 2021 02:07:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=5gtHRujbA++rmZKVlVKXeDrh5bnEaeS8o439txwjvSA=; b=kTfjDSsgaq9qbDV1ucHbETvQ/8/ik6lZYd1sDSYBYvzO5YOC2355x5r6WEZJsMFAaq TjWIPb6hh9Qyd0hvSxCnR9xvlg6lHvM/vDQAp3FLdpWv0R8Yg14Us2FuMOSTqfk58N6+ DVYackISrNedtzyFqko1Bn0lLIqV5uuAYTt78ggEYlcBeoZz0zgQ2dWp7v52moTMHu0k 1nLRAjR21BFUJscaSBAVFFb8m536QaQMIjnqjU6zGSi9KmqMhH5uEMUfJFriL2pSSle/ Lum3CioeDmXQXi+uhQfNU++N4jDqC9I52MCTiWwr86qUBCm7cxVwwfczF2cOQQyFYd8x XvPA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=5gtHRujbA++rmZKVlVKXeDrh5bnEaeS8o439txwjvSA=; b=rgacfSgQtkVApePDrWZQ59Z+SVaq23QUEyeOndzNGLhzFBZ1Dm0EriUltyle5Kh/sP ylexXjPkrHPr63PLV84ujYpzSWtRTdebIgPaLgAxWBeiGOOgQWOWvaD2co0DGPd0Ll2W OKVX1Rna+1xLX3v5DSKyC1oA3d018HkaTMO3XPQSZPvsWpcDhzkF+Pnb+vhuWEX0c67z vpJ7zHWa5Fq52xdbAA8aJ0t7wxaIIJJDWkKeB/mKU7eMiGeyRv6IzPUwHiQugb1mUie/ zPNinwxufx7h2InJmZwqa5cCicxugeNJSXNQjPL5u6EpNZbj7Bj8PfyQnc5dQIlaqutH 7owg== X-Gm-Message-State: AOAM533XbEFh2SE3CK2IbEMFy+yangwi8RPSl4LRQJ1yl/QVsjTQlQ0i ODUO7ogCtJJJiTT8S5kjhmE= X-Google-Smtp-Source: ABdhPJzF3v2NF1BehS+3u+lw1sBLeXSGTnvsmTmfUvY3oAh8WDf0nwHq2EO4QH5xarQi9gLUtb3rjQ== X-Received: by 2002:adf:fa45:: with SMTP id y5mr5575639wrr.311.1621328832404; Tue, 18 May 2021 02:07:12 -0700 (PDT) Received: from amanieu-laptop.home ([2a00:23c6:f081:f801:91cf:b949:c46c:f5a9]) by smtp.gmail.com with ESMTPSA id z17sm7520306wrt.81.2021.05.18.02.07.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 May 2021 02:07:12 -0700 (PDT) From: Amanieu d'Antras Cc: Amanieu d'Antras , Ryan Houdek , Catalin Marinas , Will Deacon , Mark Rutland , Steven Price , Arnd Bergmann , David Laight , Mark Brown , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [RESEND PATCH v4 7/8] arm64: Forbid calling compat sigreturn from 64-bit tasks Date: Tue, 18 May 2021 10:06:57 +0100 Message-Id: <20210518090658.9519-8-amanieu@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210518090658.9519-1-amanieu@gmail.com> References: <20210518090658.9519-1-amanieu@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It's impossible for this syscall to do anything sensible in this context. Signed-off-by: Amanieu d'Antras Co-developed-by: Ryan Houdek Signed-off-by: Ryan Houdek --- arch/arm64/kernel/signal32.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c index 2f507f565c48..e2bdd1eaefd8 100644 --- a/arch/arm64/kernel/signal32.c +++ b/arch/arm64/kernel/signal32.c @@ -237,6 +237,10 @@ COMPAT_SYSCALL_DEFINE0(sigreturn) /* Always make any pending restarted system calls return -EINTR */ current->restart_block.fn = do_no_restart_syscall; + /* Reject attempts to call this from a 64-bit process. */ + if (!is_compat_task()) + goto badframe; + /* * Since we stacked the signal on a 64-bit boundary, * then 'sp' should be word aligned here. If it's @@ -268,6 +272,10 @@ COMPAT_SYSCALL_DEFINE0(rt_sigreturn) /* Always make any pending restarted system calls return -EINTR */ current->restart_block.fn = do_no_restart_syscall; + /* Reject attempts to call this from a 64-bit process. */ + if (!is_compat_task()) + goto badframe; + /* * Since we stacked the signal on a 64-bit boundary, * then 'sp' should be word aligned here. If it's -- 2.31.1