From 9999e48639b3cecb08ffb37358bcba3b48161b29 Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Fri, 10 May 2024 08:50:17 +0000 Subject: [PATCH] add ax88772_rst --- kernel/fs/nsfs.c | 82 ++++++++++++++++++++++++++-------------- 1 files changed, 53 insertions(+), 29 deletions(-) diff --git a/kernel/fs/nsfs.c b/kernel/fs/nsfs.c index 30d150a..800c1d0 100644 --- a/kernel/fs/nsfs.c +++ b/kernel/fs/nsfs.c @@ -1,7 +1,9 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/mount.h> +#include <linux/pseudo_fs.h> #include <linux/file.h> #include <linux/fs.h> +#include <linux/proc_fs.h> #include <linux/proc_ns.h> #include <linux/magic.h> #include <linux/ktime.h> @@ -9,6 +11,8 @@ #include <linux/user_namespace.h> #include <linux/nsfs.h> #include <linux/uaccess.h> + +#include "internal.h" static struct vfsmount *nsfs_mnt; @@ -51,7 +55,7 @@ ns->ops->put(ns); } -static void *__ns_get_path(struct path *path, struct ns_common *ns) +static int __ns_get_path(struct path *path, struct ns_common *ns) { struct vfsmount *mnt = nsfs_mnt; struct dentry *dentry; @@ -70,13 +74,13 @@ got_it: path->mnt = mntget(mnt); path->dentry = dentry; - return NULL; + return 0; slow: rcu_read_unlock(); inode = new_inode_pseudo(mnt->mnt_sb); if (!inode) { ns->ops->put(ns); - return ERR_PTR(-ENOMEM); + return -ENOMEM; } inode->i_ino = ns->inum; inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); @@ -88,7 +92,7 @@ dentry = d_alloc_anon(mnt->mnt_sb); if (!dentry) { iput(inode); - return ERR_PTR(-ENOMEM); + return -ENOMEM; } d_instantiate(dentry, inode); dentry->d_fsdata = (void *)ns->ops; @@ -97,25 +101,23 @@ d_delete(dentry); /* make sure ->d_prune() does nothing */ dput(dentry); cpu_relax(); - return ERR_PTR(-EAGAIN); + return -EAGAIN; } goto got_it; } -void *ns_get_path_cb(struct path *path, ns_get_path_helper_t *ns_get_cb, +int ns_get_path_cb(struct path *path, ns_get_path_helper_t *ns_get_cb, void *private_data) { - struct ns_common *ns; - void *ret; + int ret; -again: - ns = ns_get_cb(private_data); - if (!ns) - return ERR_PTR(-ENOENT); + do { + struct ns_common *ns = ns_get_cb(private_data); + if (!ns) + return -ENOENT; + ret = __ns_get_path(path, ns); + } while (ret == -EAGAIN); - ret = __ns_get_path(path, ns); - if (IS_ERR(ret) && PTR_ERR(ret) == -EAGAIN) - goto again; return ret; } @@ -131,7 +133,7 @@ return args->ns_ops->get(args->task); } -void *ns_get_path(struct path *path, struct task_struct *task, +int ns_get_path(struct path *path, struct task_struct *task, const struct proc_ns_operations *ns_ops) { struct ns_get_path_task_args args = { @@ -147,14 +149,14 @@ { struct path path = {}; struct file *f; - void *err; + int err; int fd; fd = get_unused_fd_flags(O_CLOEXEC); if (fd < 0) return fd; - while (1) { + do { struct ns_common *relative; relative = get_ns(ns); @@ -164,13 +166,11 @@ } err = __ns_get_path(&path, relative); - if (IS_ERR(err) && PTR_ERR(err) == -EAGAIN) - continue; - break; - } - if (IS_ERR(err)) { + } while (err == -EAGAIN); + + if (err) { put_unused_fd(fd); - return PTR_ERR(err); + return err; } f = dentry_open(&path, O_RDONLY, current_cred()); @@ -229,6 +229,11 @@ return res; } +bool proc_ns_file(const struct file *file) +{ + return file->f_op == &ns_file_operations; +} + struct file *proc_ns_fget(int fd) { struct file *file; @@ -247,6 +252,20 @@ return ERR_PTR(-EINVAL); } +/** + * ns_match() - Returns true if current namespace matches dev/ino provided. + * @ns_common: current ns + * @dev: dev_t from nsfs that will be matched against current nsfs + * @ino: ino_t from nsfs that will be matched against current nsfs + * + * Return: true if dev and ino matches the current nsfs. + */ +bool ns_match(const struct ns_common *ns, dev_t dev, ino_t ino) +{ + return (ns->inum == ino) && (nsfs_mnt->mnt_sb->s_dev == dev); +} + + static int nsfs_show_path(struct seq_file *seq, struct dentry *dentry) { struct inode *inode = d_inode(dentry); @@ -261,15 +280,20 @@ .evict_inode = nsfs_evict, .show_path = nsfs_show_path, }; -static struct dentry *nsfs_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data) + +static int nsfs_init_fs_context(struct fs_context *fc) { - return mount_pseudo(fs_type, "nsfs:", &nsfs_ops, - &ns_dentry_operations, NSFS_MAGIC); + struct pseudo_fs_context *ctx = init_pseudo(fc, NSFS_MAGIC); + if (!ctx) + return -ENOMEM; + ctx->ops = &nsfs_ops; + ctx->dops = &ns_dentry_operations; + return 0; } + static struct file_system_type nsfs = { .name = "nsfs", - .mount = nsfs_mount, + .init_fs_context = nsfs_init_fs_context, .kill_sb = kill_anon_super, }; -- Gitblit v1.6.2