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=-19.0 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 0FD32C43333 for ; Mon, 15 Mar 2021 14:10:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E42FF64E86 for ; Mon, 15 Mar 2021 14:10:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234645AbhCOOKH (ORCPT ); Mon, 15 Mar 2021 10:10:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:53260 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234655AbhCOOEo (ORCPT ); Mon, 15 Mar 2021 10:04:44 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 97F8464F38; Mon, 15 Mar 2021 14:04:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1615817083; bh=lv+0TvJd6eDnBA65zQK+qLe6zQ/VSNK8Tkf105+Wgi8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mYqZvrhLGOpg0fGD7WrofLZtnzcYuY7quSFUZWFsRZIoBsq7PZKRMzilopcQs8cw6 eOjf5s8yoC2OnC3ygKDdIeV8JPWcT2i6v8SmHLp8hSLc7683IZgSZHpDB1o7tM/24Q JSAfU1Wgk65l0WQUyZq5cfXrBgTM/+rDHjCzfqV0= From: gregkh@linuxfoundation.org To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andy Lutomirski , Thomas Gleixner , Borislav Petkov Subject: [PATCH 5.11 291/306] x86/entry: Fix entry/exit mismatch on failed fast 32-bit syscalls Date: Mon, 15 Mar 2021 14:55:54 +0100 Message-Id: <20210315135517.526776954@linuxfoundation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210315135507.611436477@linuxfoundation.org> References: <20210315135507.611436477@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: Greg Kroah-Hartman From: Andy Lutomirski commit 5d5675df792ff67e74a500c4c94db0f99e6a10ef upstream. On a 32-bit fast syscall that fails to read its arguments from user memory, the kernel currently does syscall exit work but not syscall entry work. This confuses audit and ptrace. For example: $ ./tools/testing/selftests/x86/syscall_arg_fault_32 ... strace: pid 264258: entering, ptrace_syscall_info.op == 2 ... This is a minimal fix intended for ease of backporting. A more complete cleanup is coming. Fixes: 0b085e68f407 ("x86/entry: Consolidate 32/64 bit syscall entry") Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/8c82296ddf803b91f8d1e5eac89e5803ba54ab0e.1614884673.git.luto@kernel.org Signed-off-by: Greg Kroah-Hartman --- arch/x86/entry/common.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -128,7 +128,8 @@ static noinstr bool __do_fast_syscall_32 regs->ax = -EFAULT; instrumentation_end(); - syscall_exit_to_user_mode(regs); + local_irq_disable(); + irqentry_exit_to_user_mode(regs); return false; }