From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- fs/init.c | 269 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 269 insertions(+) create mode 100644 fs/init.c (limited to 'fs/init.c') diff --git a/fs/init.c b/fs/init.c new file mode 100644 index 000000000..5c36adaa9 --- /dev/null +++ b/fs/init.c @@ -0,0 +1,269 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Routines that mimic syscalls, but don't use the user address space or file + * descriptors. Only for init/ and related early init code. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +int __init init_mount(const char *dev_name, const char *dir_name, + const char *type_page, unsigned long flags, void *data_page) +{ + struct path path; + int ret; + + ret = kern_path(dir_name, LOOKUP_FOLLOW, &path); + if (ret) + return ret; + ret = path_mount(dev_name, &path, type_page, flags, data_page); + path_put(&path); + return ret; +} + +int __init init_umount(const char *name, int flags) +{ + int lookup_flags = LOOKUP_MOUNTPOINT; + struct path path; + int ret; + + if (!(flags & UMOUNT_NOFOLLOW)) + lookup_flags |= LOOKUP_FOLLOW; + ret = kern_path(name, lookup_flags, &path); + if (ret) + return ret; + return path_umount(&path, flags); +} + +int __init init_chdir(const char *filename) +{ + struct path path; + int error; + + error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path); + if (error) + return error; + error = path_permission(&path, MAY_EXEC | MAY_CHDIR); + if (!error) + set_fs_pwd(current->fs, &path); + path_put(&path); + return error; +} + +int __init init_chroot(const char *filename) +{ + struct path path; + int error; + + error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path); + if (error) + return error; + error = path_permission(&path, MAY_EXEC | MAY_CHDIR); + if (error) + goto dput_and_out; + error = -EPERM; + if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT)) + goto dput_and_out; + error = security_path_chroot(&path); + if (error) + goto dput_and_out; + set_fs_root(current->fs, &path); +dput_and_out: + path_put(&path); + return error; +} + +int __init init_chown(const char *filename, uid_t user, gid_t group, int flags) +{ + int lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; + struct path path; + int error; + + error = kern_path(filename, lookup_flags, &path); + if (error) + return error; + error = mnt_want_write(path.mnt); + if (!error) { + error = chown_common(&path, user, group); + mnt_drop_write(path.mnt); + } + path_put(&path); + return error; +} + +int __init init_chmod(const char *filename, umode_t mode) +{ + struct path path; + int error; + + error = kern_path(filename, LOOKUP_FOLLOW, &path); + if (error) + return error; + error = chmod_common(&path, mode); + path_put(&path); + return error; +} + +int __init init_eaccess(const char *filename) +{ + struct path path; + int error; + + error = kern_path(filename, LOOKUP_FOLLOW, &path); + if (error) + return error; + error = path_permission(&path, MAY_ACCESS); + path_put(&path); + return error; +} + +int __init init_stat(const char *filename, struct kstat *stat, int flags) +{ + int lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; + struct path path; + int error; + + error = kern_path(filename, lookup_flags, &path); + if (error) + return error; + error = vfs_getattr(&path, stat, STATX_BASIC_STATS, + flags | AT_NO_AUTOMOUNT); + path_put(&path); + 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(mnt_user_ns(path.mnt), 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; + struct path old_path, new_path; + struct user_namespace *mnt_userns; + int error; + + error = kern_path(oldname, 0, &old_path); + if (error) + return error; + + new_dentry = kern_path_create(AT_FDCWD, newname, &new_path, 0); + error = PTR_ERR(new_dentry); + if (IS_ERR(new_dentry)) + goto out; + + error = -EXDEV; + if (old_path.mnt != new_path.mnt) + goto out_dput; + mnt_userns = mnt_user_ns(new_path.mnt); + error = may_linkat(mnt_userns, &old_path); + if (unlikely(error)) + goto out_dput; + error = security_path_link(old_path.dentry, &new_path, new_dentry); + if (error) + goto out_dput; + error = vfs_link(old_path.dentry, mnt_userns, new_path.dentry->d_inode, + new_dentry, NULL); +out_dput: + done_path_create(&new_path, new_dentry); +out: + path_put(&old_path); + return error; +} + +int __init init_symlink(const char *oldname, const char *newname) +{ + struct dentry *dentry; + struct path path; + int error; + + dentry = kern_path_create(AT_FDCWD, newname, &path, 0); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + error = security_path_symlink(&path, dentry, oldname); + if (!error) + error = vfs_symlink(mnt_user_ns(path.mnt), path.dentry->d_inode, + dentry, oldname); + done_path_create(&path, dentry); + return error; +} + +int __init init_unlink(const char *pathname) +{ + return do_unlinkat(AT_FDCWD, getname_kernel(pathname)); +} + +int __init init_mkdir(const char *pathname, umode_t mode) +{ + struct dentry *dentry; + struct path path; + int error; + + dentry = kern_path_create(AT_FDCWD, pathname, &path, LOOKUP_DIRECTORY); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + if (!IS_POSIXACL(path.dentry->d_inode)) + mode &= ~current_umask(); + error = security_path_mkdir(&path, dentry, mode); + if (!error) + error = vfs_mkdir(mnt_user_ns(path.mnt), path.dentry->d_inode, + dentry, mode); + done_path_create(&path, dentry); + return error; +} + +int __init init_rmdir(const char *pathname) +{ + return do_rmdir(AT_FDCWD, getname_kernel(pathname)); +} + +int __init init_utimes(char *filename, struct timespec64 *ts) +{ + struct path path; + int error; + + error = kern_path(filename, 0, &path); + if (error) + return error; + error = vfs_utimes(&path, ts); + path_put(&path); + return error; +} + +int __init init_dup(struct file *file) +{ + int fd; + + fd = get_unused_fd_flags(0); + if (fd < 0) + return fd; + fd_install(fd, get_file(file)); + return 0; +} -- cgit v1.2.3