From patchwork Mon Jun 15 12:53:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11604835 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5A86414E3 for ; Mon, 15 Jun 2020 12:54:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 408632076A for ; Mon, 15 Jun 2020 12:54:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="qDldmTPV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730183AbgFOMyG (ORCPT ); Mon, 15 Jun 2020 08:54:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730174AbgFOMyB (ORCPT ); Mon, 15 Jun 2020 08:54:01 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 328BDC061A0E; Mon, 15 Jun 2020 05:54:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=A27NnadNuuURtrOVcCToxHxc4WmXNjPcYjKSm7r2Lj4=; b=qDldmTPVN54waXJTZy3r7RjsuS ZgBBd2sVr6kjLK2n8wGfku54G4YbaUzHRpIKbctytGPmcA7OGDP7bVpYUxuR/o0JVmWOhVclfOTHG TEVgX5ttrLq6hS7b/hHa0JvgTbIwB2dnEG4GnKUdtpkwVWs2KAvuKFMME5lnzE2Ak1NoAPsjmMlGK i53/7hp56aSzEBxr7GrnsoE83HshG4Xbt3f9hTkuM+3GNHzqnxpzQtwvrCSvENd9P51mOKfB69hME FHlfzdeMjSWZPobHqQMQPdIEPjM/GrxkAo1orACziwLqDQ5bGgC25e6hXQBIuXzJiS74xA9WpZI/B Yg59S9JA==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkoci-0000wd-NH; Mon, 15 Jun 2020 12:54:01 +0000 From: Christoph Hellwig To: linux-kernel@vger.kernel.org Cc: "H. Peter Anvin" , Song Liu , Al Viro , Linus Torvalds , linux-raid@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 15/16] init: open code setting up stdin/stdout/stderr Date: Mon, 15 Jun 2020 14:53:22 +0200 Message-Id: <20200615125323.930983-16-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200615125323.930983-1-hch@lst.de> References: <20200615125323.930983-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Don't rely on the implicit set_fs(KERNEL_DS) for ksys_open to work, but instead open a struct file for /dev/console and then install it as FD 0/1/2 manually. Signed-off-by: Christoph Hellwig --- fs/file.c | 7 +------ include/linux/syscalls.h | 1 - init/main.c | 16 ++++++++++------ 3 files changed, 11 insertions(+), 13 deletions(-) diff --git a/fs/file.c b/fs/file.c index abb8b7081d7a44..85b7993165dd2f 100644 --- a/fs/file.c +++ b/fs/file.c @@ -985,7 +985,7 @@ SYSCALL_DEFINE2(dup2, unsigned int, oldfd, unsigned int, newfd) return ksys_dup3(oldfd, newfd, 0); } -int ksys_dup(unsigned int fildes) +SYSCALL_DEFINE1(dup, unsigned int, fildes) { int ret = -EBADF; struct file *file = fget_raw(fildes); @@ -1000,11 +1000,6 @@ int ksys_dup(unsigned int fildes) return ret; } -SYSCALL_DEFINE1(dup, unsigned int, fildes) -{ - return ksys_dup(fildes); -} - int f_dupfd(unsigned int from, struct file *file, unsigned flags) { int err; diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 5215bd413b6eb1..bde56097a7c27e 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1237,7 +1237,6 @@ asmlinkage long sys_ni_syscall(void); */ int ksys_umount(char __user *name, int flags); -int ksys_dup(unsigned int fildes); int ksys_chroot(const char __user *filename); ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count); int ksys_chdir(const char __user *filename); diff --git a/init/main.c b/init/main.c index 0ead83e86b5aa2..db0621dfbb0468 100644 --- a/init/main.c +++ b/init/main.c @@ -1457,15 +1457,19 @@ static int __ref kernel_init(void *unused) "See Linux Documentation/admin-guide/init.rst for guidance."); } +/* Open /dev/console, for stdin/stdout/stderr, this should never fail */ void console_on_rootfs(void) { - /* Open the /dev/console as stdin, this should never fail */ - if (ksys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0) - pr_err("Warning: unable to open an initial console.\n"); + struct file *file = filp_open("/dev/console", O_RDWR, 0); - /* create stdout/stderr */ - (void) ksys_dup(0); - (void) ksys_dup(0); + if (IS_ERR(file)) { + pr_err("Warning: unable to open an initial console.\n"); + return; + } + get_file_rcu_many(file, 2); + fd_install(get_unused_fd_flags(0), file); + fd_install(get_unused_fd_flags(0), file); + fd_install(get_unused_fd_flags(0), file); } static noinline void __init kernel_init_freeable(void)