1 files changed, 386 insertions, 0 deletions
diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c
new file mode 100644
index 000000000..affa70360
--- /dev/null
+++ b/fs/autofs/inode.c
@@ -0,0 +1,386 @@
+// 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;
+}