|  | // SPDX-License-Identifier: GPL-2.0-or-later | 
|  | /* | 
|  | * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved | 
|  | * Copyright 2005-2006 Ian Kent <raven@themaw.net> | 
|  | */ | 
|  |  | 
|  | #include <linux/seq_file.h> | 
|  | #include <linux/pagemap.h> | 
|  | #include <linux/parser.h> | 
|  |  | 
|  | #include "autofs_i.h" | 
|  |  | 
|  | struct autofs_info *autofs_new_ino(struct autofs_sb_info *sbi) | 
|  | { | 
|  | struct autofs_info *ino; | 
|  |  | 
|  | ino = kzalloc(sizeof(*ino), GFP_KERNEL); | 
|  | if (ino) { | 
|  | INIT_LIST_HEAD(&ino->active); | 
|  | INIT_LIST_HEAD(&ino->expiring); | 
|  | ino->last_used = jiffies; | 
|  | ino->sbi = sbi; | 
|  | ino->count = 1; | 
|  | } | 
|  | return ino; | 
|  | } | 
|  |  | 
|  | void autofs_clean_ino(struct autofs_info *ino) | 
|  | { | 
|  | ino->uid = GLOBAL_ROOT_UID; | 
|  | ino->gid = GLOBAL_ROOT_GID; | 
|  | ino->last_used = jiffies; | 
|  | } | 
|  |  | 
|  | void autofs_free_ino(struct autofs_info *ino) | 
|  | { | 
|  | kfree_rcu(ino, rcu); | 
|  | } | 
|  |  | 
|  | void autofs_kill_sb(struct super_block *sb) | 
|  | { | 
|  | struct autofs_sb_info *sbi = autofs_sbi(sb); | 
|  |  | 
|  | /* | 
|  | * In the event of a failure in get_sb_nodev the superblock | 
|  | * info is not present so nothing else has been setup, so | 
|  | * just call kill_anon_super when we are called from | 
|  | * deactivate_super. | 
|  | */ | 
|  | if (sbi) { | 
|  | /* Free wait queues, close pipe */ | 
|  | autofs_catatonic_mode(sbi); | 
|  | put_pid(sbi->oz_pgrp); | 
|  | } | 
|  |  | 
|  | pr_debug("shutting down\n"); | 
|  | kill_litter_super(sb); | 
|  | if (sbi) | 
|  | kfree_rcu(sbi, rcu); | 
|  | } | 
|  |  | 
|  | static int autofs_show_options(struct seq_file *m, struct dentry *root) | 
|  | { | 
|  | struct autofs_sb_info *sbi = autofs_sbi(root->d_sb); | 
|  | struct inode *root_inode = d_inode(root->d_sb->s_root); | 
|  |  | 
|  | if (!sbi) | 
|  | return 0; | 
|  |  | 
|  | seq_printf(m, ",fd=%d", sbi->pipefd); | 
|  | if (!uid_eq(root_inode->i_uid, GLOBAL_ROOT_UID)) | 
|  | seq_printf(m, ",uid=%u", | 
|  | from_kuid_munged(&init_user_ns, root_inode->i_uid)); | 
|  | if (!gid_eq(root_inode->i_gid, GLOBAL_ROOT_GID)) | 
|  | seq_printf(m, ",gid=%u", | 
|  | from_kgid_munged(&init_user_ns, root_inode->i_gid)); | 
|  | seq_printf(m, ",pgrp=%d", pid_vnr(sbi->oz_pgrp)); | 
|  | seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ); | 
|  | seq_printf(m, ",minproto=%d", sbi->min_proto); | 
|  | seq_printf(m, ",maxproto=%d", sbi->max_proto); | 
|  |  | 
|  | if (autofs_type_offset(sbi->type)) | 
|  | seq_puts(m, ",offset"); | 
|  | else if (autofs_type_direct(sbi->type)) | 
|  | seq_puts(m, ",direct"); | 
|  | else | 
|  | seq_puts(m, ",indirect"); | 
|  | if (sbi->flags & AUTOFS_SBI_STRICTEXPIRE) | 
|  | seq_puts(m, ",strictexpire"); | 
|  | if (sbi->flags & AUTOFS_SBI_IGNORE) | 
|  | seq_puts(m, ",ignore"); | 
|  | #ifdef CONFIG_CHECKPOINT_RESTORE | 
|  | if (sbi->pipe) | 
|  | seq_printf(m, ",pipe_ino=%ld", file_inode(sbi->pipe)->i_ino); | 
|  | else | 
|  | seq_puts(m, ",pipe_ino=-1"); | 
|  | #endif | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void autofs_evict_inode(struct inode *inode) | 
|  | { | 
|  | clear_inode(inode); | 
|  | kfree(inode->i_private); | 
|  | } | 
|  |  | 
|  | static const struct super_operations autofs_sops = { | 
|  | .statfs		= simple_statfs, | 
|  | .show_options	= autofs_show_options, | 
|  | .evict_inode	= autofs_evict_inode, | 
|  | }; | 
|  |  | 
|  | enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto, | 
|  | Opt_indirect, Opt_direct, Opt_offset, Opt_strictexpire, | 
|  | Opt_ignore}; | 
|  |  | 
|  | static const match_table_t tokens = { | 
|  | {Opt_fd, "fd=%u"}, | 
|  | {Opt_uid, "uid=%u"}, | 
|  | {Opt_gid, "gid=%u"}, | 
|  | {Opt_pgrp, "pgrp=%u"}, | 
|  | {Opt_minproto, "minproto=%u"}, | 
|  | {Opt_maxproto, "maxproto=%u"}, | 
|  | {Opt_indirect, "indirect"}, | 
|  | {Opt_direct, "direct"}, | 
|  | {Opt_offset, "offset"}, | 
|  | {Opt_strictexpire, "strictexpire"}, | 
|  | {Opt_ignore, "ignore"}, | 
|  | {Opt_err, NULL} | 
|  | }; | 
|  |  | 
|  | static int parse_options(char *options, | 
|  | struct inode *root, int *pgrp, bool *pgrp_set, | 
|  | struct autofs_sb_info *sbi) | 
|  | { | 
|  | char *p; | 
|  | substring_t args[MAX_OPT_ARGS]; | 
|  | int option; | 
|  | int pipefd = -1; | 
|  | kuid_t uid; | 
|  | kgid_t gid; | 
|  |  | 
|  | root->i_uid = current_uid(); | 
|  | root->i_gid = current_gid(); | 
|  |  | 
|  | sbi->min_proto = AUTOFS_MIN_PROTO_VERSION; | 
|  | sbi->max_proto = AUTOFS_MAX_PROTO_VERSION; | 
|  |  | 
|  | sbi->pipefd = -1; | 
|  |  | 
|  | if (!options) | 
|  | return 1; | 
|  |  | 
|  | while ((p = strsep(&options, ",")) != NULL) { | 
|  | int token; | 
|  |  | 
|  | if (!*p) | 
|  | continue; | 
|  |  | 
|  | token = match_token(p, tokens, args); | 
|  | switch (token) { | 
|  | case Opt_fd: | 
|  | if (match_int(args, &pipefd)) | 
|  | return 1; | 
|  | sbi->pipefd = pipefd; | 
|  | break; | 
|  | case Opt_uid: | 
|  | if (match_int(args, &option)) | 
|  | return 1; | 
|  | uid = make_kuid(current_user_ns(), option); | 
|  | if (!uid_valid(uid)) | 
|  | return 1; | 
|  | root->i_uid = uid; | 
|  | break; | 
|  | case Opt_gid: | 
|  | if (match_int(args, &option)) | 
|  | return 1; | 
|  | gid = make_kgid(current_user_ns(), option); | 
|  | if (!gid_valid(gid)) | 
|  | return 1; | 
|  | root->i_gid = gid; | 
|  | break; | 
|  | case Opt_pgrp: | 
|  | if (match_int(args, &option)) | 
|  | return 1; | 
|  | *pgrp = option; | 
|  | *pgrp_set = true; | 
|  | break; | 
|  | case Opt_minproto: | 
|  | if (match_int(args, &option)) | 
|  | return 1; | 
|  | sbi->min_proto = option; | 
|  | break; | 
|  | case Opt_maxproto: | 
|  | if (match_int(args, &option)) | 
|  | return 1; | 
|  | sbi->max_proto = option; | 
|  | break; | 
|  | case Opt_indirect: | 
|  | set_autofs_type_indirect(&sbi->type); | 
|  | break; | 
|  | case Opt_direct: | 
|  | set_autofs_type_direct(&sbi->type); | 
|  | break; | 
|  | case Opt_offset: | 
|  | set_autofs_type_offset(&sbi->type); | 
|  | break; | 
|  | case Opt_strictexpire: | 
|  | sbi->flags |= AUTOFS_SBI_STRICTEXPIRE; | 
|  | break; | 
|  | case Opt_ignore: | 
|  | sbi->flags |= AUTOFS_SBI_IGNORE; | 
|  | break; | 
|  | default: | 
|  | return 1; | 
|  | } | 
|  | } | 
|  | return (sbi->pipefd < 0); | 
|  | } | 
|  |  | 
|  | int autofs_fill_super(struct super_block *s, void *data, int silent) | 
|  | { | 
|  | struct inode *root_inode; | 
|  | struct dentry *root; | 
|  | struct file *pipe; | 
|  | struct autofs_sb_info *sbi; | 
|  | struct autofs_info *ino; | 
|  | int pgrp = 0; | 
|  | bool pgrp_set = false; | 
|  | int ret = -EINVAL; | 
|  |  | 
|  | sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); | 
|  | if (!sbi) | 
|  | return -ENOMEM; | 
|  | pr_debug("starting up, sbi = %p\n", sbi); | 
|  |  | 
|  | s->s_fs_info = sbi; | 
|  | sbi->magic = AUTOFS_SBI_MAGIC; | 
|  | sbi->pipefd = -1; | 
|  | sbi->pipe = NULL; | 
|  | sbi->exp_timeout = 0; | 
|  | sbi->oz_pgrp = NULL; | 
|  | sbi->sb = s; | 
|  | sbi->version = 0; | 
|  | sbi->sub_version = 0; | 
|  | sbi->flags = AUTOFS_SBI_CATATONIC; | 
|  | set_autofs_type_indirect(&sbi->type); | 
|  | sbi->min_proto = 0; | 
|  | sbi->max_proto = 0; | 
|  | mutex_init(&sbi->wq_mutex); | 
|  | mutex_init(&sbi->pipe_mutex); | 
|  | spin_lock_init(&sbi->fs_lock); | 
|  | sbi->queues = NULL; | 
|  | spin_lock_init(&sbi->lookup_lock); | 
|  | INIT_LIST_HEAD(&sbi->active_list); | 
|  | INIT_LIST_HEAD(&sbi->expiring_list); | 
|  | s->s_blocksize = 1024; | 
|  | s->s_blocksize_bits = 10; | 
|  | s->s_magic = AUTOFS_SUPER_MAGIC; | 
|  | s->s_op = &autofs_sops; | 
|  | s->s_d_op = &autofs_dentry_operations; | 
|  | s->s_time_gran = 1; | 
|  |  | 
|  | /* | 
|  | * Get the root inode and dentry, but defer checking for errors. | 
|  | */ | 
|  | ino = autofs_new_ino(sbi); | 
|  | if (!ino) { | 
|  | ret = -ENOMEM; | 
|  | goto fail_free; | 
|  | } | 
|  | root_inode = autofs_get_inode(s, S_IFDIR | 0755); | 
|  | root = d_make_root(root_inode); | 
|  | if (!root) { | 
|  | ret = -ENOMEM; | 
|  | goto fail_ino; | 
|  | } | 
|  | pipe = NULL; | 
|  |  | 
|  | root->d_fsdata = ino; | 
|  |  | 
|  | /* Can this call block? */ | 
|  | if (parse_options(data, root_inode, &pgrp, &pgrp_set, sbi)) { | 
|  | pr_err("called with bogus options\n"); | 
|  | goto fail_dput; | 
|  | } | 
|  |  | 
|  | /* Test versions first */ | 
|  | if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION || | 
|  | sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) { | 
|  | pr_err("kernel does not match daemon version " | 
|  | "daemon (%d, %d) kernel (%d, %d)\n", | 
|  | sbi->min_proto, sbi->max_proto, | 
|  | AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION); | 
|  | goto fail_dput; | 
|  | } | 
|  |  | 
|  | /* Establish highest kernel protocol version */ | 
|  | if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION) | 
|  | sbi->version = AUTOFS_MAX_PROTO_VERSION; | 
|  | else | 
|  | sbi->version = sbi->max_proto; | 
|  | sbi->sub_version = AUTOFS_PROTO_SUBVERSION; | 
|  |  | 
|  | if (pgrp_set) { | 
|  | sbi->oz_pgrp = find_get_pid(pgrp); | 
|  | if (!sbi->oz_pgrp) { | 
|  | pr_err("could not find process group %d\n", | 
|  | pgrp); | 
|  | goto fail_dput; | 
|  | } | 
|  | } else { | 
|  | sbi->oz_pgrp = get_task_pid(current, PIDTYPE_PGID); | 
|  | } | 
|  |  | 
|  | if (autofs_type_trigger(sbi->type)) | 
|  | __managed_dentry_set_managed(root); | 
|  |  | 
|  | root_inode->i_fop = &autofs_root_operations; | 
|  | root_inode->i_op = &autofs_dir_inode_operations; | 
|  |  | 
|  | pr_debug("pipe fd = %d, pgrp = %u\n", | 
|  | sbi->pipefd, pid_nr(sbi->oz_pgrp)); | 
|  | pipe = fget(sbi->pipefd); | 
|  |  | 
|  | if (!pipe) { | 
|  | pr_err("could not open pipe file descriptor\n"); | 
|  | goto fail_put_pid; | 
|  | } | 
|  | ret = autofs_prepare_pipe(pipe); | 
|  | if (ret < 0) | 
|  | goto fail_fput; | 
|  | sbi->pipe = pipe; | 
|  | sbi->flags &= ~AUTOFS_SBI_CATATONIC; | 
|  |  | 
|  | /* | 
|  | * Success! Install the root dentry now to indicate completion. | 
|  | */ | 
|  | s->s_root = root; | 
|  | return 0; | 
|  |  | 
|  | /* | 
|  | * Failure ... clean up. | 
|  | */ | 
|  | fail_fput: | 
|  | pr_err("pipe file descriptor does not contain proper ops\n"); | 
|  | fput(pipe); | 
|  | fail_put_pid: | 
|  | put_pid(sbi->oz_pgrp); | 
|  | fail_dput: | 
|  | dput(root); | 
|  | goto fail_free; | 
|  | fail_ino: | 
|  | autofs_free_ino(ino); | 
|  | fail_free: | 
|  | kfree(sbi); | 
|  | s->s_fs_info = NULL; | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | struct inode *autofs_get_inode(struct super_block *sb, umode_t mode) | 
|  | { | 
|  | struct inode *inode = new_inode(sb); | 
|  |  | 
|  | if (inode == NULL) | 
|  | return NULL; | 
|  |  | 
|  | inode->i_mode = mode; | 
|  | if (sb->s_root) { | 
|  | inode->i_uid = d_inode(sb->s_root)->i_uid; | 
|  | inode->i_gid = d_inode(sb->s_root)->i_gid; | 
|  | } | 
|  | inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); | 
|  | inode->i_ino = get_next_ino(); | 
|  |  | 
|  | if (S_ISDIR(mode)) { | 
|  | set_nlink(inode, 2); | 
|  | inode->i_op = &autofs_dir_inode_operations; | 
|  | inode->i_fop = &autofs_dir_operations; | 
|  | } else if (S_ISLNK(mode)) { | 
|  | inode->i_op = &autofs_symlink_inode_operations; | 
|  | } else | 
|  | WARN_ON(1); | 
|  |  | 
|  | return inode; | 
|  | } |