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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /fs/init.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/init.c')
-rw-r--r--fs/init.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/fs/init.c b/fs/init.c
new file mode 100644
index 0000000000..9684406a84
--- /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 <linux/init.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/fs.h>
+#include <linux/fs_struct.h>
+#include <linux/file.h>
+#include <linux/init_syscalls.h>
+#include <linux/security.h>
+#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_idmap(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 mnt_idmap *idmap;
+ 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;
+ idmap = mnt_idmap(new_path.mnt);
+ error = may_linkat(idmap, &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, idmap, 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_idmap(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_idmap(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;
+}