From patchwork Sun Jul 26 07:13:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11685531 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 3C97B138C for ; Sun, 26 Jul 2020 07:14:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 236B720738 for ; Sun, 26 Jul 2020 07:14:51 +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="grf+yo47" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727884AbgGZHOt (ORCPT ); Sun, 26 Jul 2020 03:14:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727815AbgGZHOp (ORCPT ); Sun, 26 Jul 2020 03:14:45 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A830C0619D2; Sun, 26 Jul 2020 00:14:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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=MJxfIJc5GcfguEdhmuCVs1Q0Ywd1gqUYWhUUmceWjfw=; b=grf+yo473sM13bqM012FJatkSK abapynIxJJ9osJbVaZG+jaBQsZh7J2n3RVqQqmUWtuwdo7i9M+yCmd3rBIyc0q801K9TxClLpjnWc BGVumqUtiD+hdPL24zOzgSz4MlDN2HyI06FzIKnftoNJrcM8p00+wJFNJQuNjp4OVfpI9kxLClrCN zQM3eSgvaNdUkMFgNnamOO7/gbnJI/LJUeFuEek5bnz7+OEbaksvrzCE7eyaeL7MA15nWCjUQuQyx n3MauqJOoGuJ1cQaOcHVquypSav86Num9KWdOfNgJHmMkL4tbM1s9mQaXzbbsQtNP+VtLnG3vK0tE Hj7boR8w==; Received: from [2001:4bb8:18c:2acc:5ff1:d0b0:8643:670e] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jzarp-0002WW-7l; Sun, 26 Jul 2020 07:14:41 +0000 From: Christoph Hellwig To: Al Viro , Linus Torvalds Cc: Greg Kroah-Hartman , "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org Subject: [PATCH 19/21] init: add an init_mknod helper Date: Sun, 26 Jul 2020 09:13:54 +0200 Message-Id: <20200726071356.287160-20-hch@lst.de> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200726071356.287160-1-hch@lst.de> References: <20200726071356.287160-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.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 Add a simple helper to mknod with a kernel space file name and switch the early init code over to it. Remove the now unused ksys_mknod. Signed-off-by: Christoph Hellwig --- fs/for_init.c | 25 +++++++++++++++++++++++++ fs/internal.h | 2 -- fs/namei.c | 2 +- include/linux/init_syscalls.h | 1 + include/linux/syscalls.h | 9 --------- init/do_mounts.h | 2 +- init/initramfs.c | 2 +- init/noinitramfs.c | 3 +-- 8 files changed, 30 insertions(+), 16 deletions(-) diff --git a/fs/for_init.c b/fs/for_init.c index 6ae3305bece1eb..50813d2913b57b 100644 --- a/fs/for_init.c +++ b/fs/for_init.c @@ -118,6 +118,31 @@ int __init init_eaccess(const char *filename) return error; } +int __init init_mknod(const char *filename, umode_t mode, unsigned int dev) +{ + struct dentry *dentry; + struct path path; + int error; + + if (S_ISFIFO(mode) || S_ISSOCK(mode)) + dev = 0; + else if (!(S_ISBLK(mode) || S_ISCHR(mode))) + return -EINVAL; + + dentry = kern_path_create(AT_FDCWD, filename, &path, 0); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + + if (!IS_POSIXACL(path.dentry->d_inode)) + mode &= ~current_umask(); + error = security_path_mknod(&path, dentry, mode, dev); + if (!error) + error = vfs_mknod(path.dentry->d_inode, dentry, mode, + new_decode_dev(dev)); + done_path_create(&path, dentry); + return error; +} + int __init init_link(const char *oldname, const char *newname) { struct dentry *new_dentry; diff --git a/fs/internal.h b/fs/internal.h index 4741e591e923bf..07e145b2f88c4a 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -62,8 +62,6 @@ extern int filename_lookup(int dfd, struct filename *name, unsigned flags, struct path *path, struct path *root); extern int vfs_path_lookup(struct dentry *, struct vfsmount *, const char *, unsigned int, struct path *); -long do_mknodat(int dfd, const char __user *filename, umode_t mode, - unsigned int dev); long do_rmdir(int dfd, struct filename *name); long do_unlinkat(int dfd, struct filename *name); int may_linkat(struct path *link); diff --git a/fs/namei.c b/fs/namei.c index d6b25dd32f4d50..fde8fe086c090d 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3564,7 +3564,7 @@ static int may_mknod(umode_t mode) } } -long do_mknodat(int dfd, const char __user *filename, umode_t mode, +static long do_mknodat(int dfd, const char __user *filename, umode_t mode, unsigned int dev) { struct dentry *dentry; diff --git a/include/linux/init_syscalls.h b/include/linux/init_syscalls.h index d808985231f8f8..fa1fe7a877795f 100644 --- a/include/linux/init_syscalls.h +++ b/include/linux/init_syscalls.h @@ -8,6 +8,7 @@ int __init init_chroot(const char *filename); int __init init_chown(const char *filename, uid_t user, gid_t group, int flags); int __init init_chmod(const char *filename, umode_t mode); int __init init_eaccess(const char *filename); +int __init init_mknod(const char *filename, umode_t mode, unsigned int dev); int __init init_link(const char *oldname, const char *newname); int __init init_symlink(const char *oldname, const char *newname); int __init init_unlink(const char *pathname); diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 5ef77a91382aa5..63046c5e9fc5d4 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1270,15 +1270,6 @@ int compat_ksys_ipc(u32 call, int first, int second, * The following kernel syscall equivalents are just wrappers to fs-internal * functions. Therefore, provide stubs to be inlined at the callsites. */ -extern long do_mknodat(int dfd, const char __user *filename, umode_t mode, - unsigned int dev); - -static inline long ksys_mknod(const char __user *filename, umode_t mode, - unsigned int dev) -{ - return do_mknodat(AT_FDCWD, filename, mode, dev); -} - extern int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group, int flag); diff --git a/init/do_mounts.h b/init/do_mounts.h index 104d8431725aeb..7a29ac3e427bab 100644 --- a/init/do_mounts.h +++ b/init/do_mounts.h @@ -17,7 +17,7 @@ extern int root_mountflags; static inline __init int create_dev(char *name, dev_t dev) { init_unlink(name); - return ksys_mknod(name, S_IFBLK|0600, new_encode_dev(dev)); + return init_mknod(name, S_IFBLK | 0600, new_encode_dev(dev)); } #ifdef CONFIG_BLK_DEV_RAM diff --git a/init/initramfs.c b/init/initramfs.c index 076e66f11bda8d..9b2d93a2eb5e4b 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -352,7 +352,7 @@ static int __init do_name(void) } else if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { if (maybe_link() == 0) { - ksys_mknod(collected, mode, rdev); + init_mknod(collected, mode, rdev); init_chown(collected, uid, gid, 0); init_chmod(collected, mode); do_utime(collected, mtime); diff --git a/init/noinitramfs.c b/init/noinitramfs.c index 94cc4df74b11f2..3d62b07f3bb9c3 100644 --- a/init/noinitramfs.c +++ b/init/noinitramfs.c @@ -22,8 +22,7 @@ static int __init default_rootfs(void) if (err < 0) goto out; - err = ksys_mknod((const char __user __force *) "/dev/console", - S_IFCHR | S_IRUSR | S_IWUSR, + err = init_mknod("/dev/console", S_IFCHR | S_IRUSR | S_IWUSR, new_encode_dev(MKDEV(5, 1))); if (err < 0) goto out;