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-rw-r--r--fs/autofs/inode.c386
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;
+}