fuse update for 4.18

The most interesting part of this update is user namespace support, mostly
 done by Eric Biederman.  This enables safe unprivileged fuse mounts within
 a user namespace.
 
 There are also a couple of fixes for bugs found by syzbot and miscellaneous
 fixes and cleanups.
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Merge tag 'fuse-update-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse updates from Miklos Szeredi:
 "The most interesting part of this update is user namespace support,
  mostly done by Eric Biederman. This enables safe unprivileged fuse
  mounts within a user namespace.

  There are also a couple of fixes for bugs found by syzbot and
  miscellaneous fixes and cleanups"

* tag 'fuse-update-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: don't keep dead fuse_conn at fuse_fill_super().
  fuse: fix control dir setup and teardown
  fuse: fix congested state leak on aborted connections
  fuse: Allow fully unprivileged mounts
  fuse: Ensure posix acls are translated outside of init_user_ns
  fuse: add writeback documentation
  fuse: honor AT_STATX_FORCE_SYNC
  fuse: honor AT_STATX_DONT_SYNC
  fuse: Restrict allow_other to the superblock's namespace or a descendant
  fuse: Support fuse filesystems outside of init_user_ns
  fuse: Fail all requests with invalid uids or gids
  fuse: Remove the buggy retranslation of pids in fuse_dev_do_read
  fuse: return -ECONNABORTED on /dev/fuse read after abort
  fuse: atomic_o_trunc should truncate pagecache
This commit is contained in:
Linus Torvalds 2018-06-07 08:50:57 -07:00
commit da315f6e03
11 changed files with 209 additions and 63 deletions

View file

@ -34,7 +34,7 @@ struct posix_acl *fuse_get_acl(struct inode *inode, int type)
return ERR_PTR(-ENOMEM);
size = fuse_getxattr(inode, name, value, PAGE_SIZE);
if (size > 0)
acl = posix_acl_from_xattr(&init_user_ns, value, size);
acl = posix_acl_from_xattr(fc->user_ns, value, size);
else if ((size == 0) || (size == -ENODATA) ||
(size == -EOPNOTSUPP && fc->no_getxattr))
acl = NULL;
@ -81,7 +81,7 @@ int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type)
if (!value)
return -ENOMEM;
ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
ret = posix_acl_to_xattr(fc->user_ns, acl, value, size);
if (ret < 0) {
kfree(value);
return ret;

View file

@ -35,7 +35,7 @@ static ssize_t fuse_conn_abort_write(struct file *file, const char __user *buf,
{
struct fuse_conn *fc = fuse_ctl_file_conn_get(file);
if (fc) {
fuse_abort_conn(fc);
fuse_abort_conn(fc, true);
fuse_conn_put(fc);
}
return count;
@ -211,10 +211,11 @@ static struct dentry *fuse_ctl_add_dentry(struct dentry *parent,
if (!dentry)
return NULL;
fc->ctl_dentry[fc->ctl_ndents++] = dentry;
inode = new_inode(fuse_control_sb);
if (!inode)
if (!inode) {
dput(dentry);
return NULL;
}
inode->i_ino = get_next_ino();
inode->i_mode = mode;
@ -228,6 +229,9 @@ static struct dentry *fuse_ctl_add_dentry(struct dentry *parent,
set_nlink(inode, nlink);
inode->i_private = fc;
d_add(dentry, inode);
fc->ctl_dentry[fc->ctl_ndents++] = dentry;
return dentry;
}
@ -284,7 +288,10 @@ void fuse_ctl_remove_conn(struct fuse_conn *fc)
for (i = fc->ctl_ndents - 1; i >= 0; i--) {
struct dentry *dentry = fc->ctl_dentry[i];
d_inode(dentry)->i_private = NULL;
d_drop(dentry);
if (!i) {
/* Get rid of submounts: */
d_invalidate(dentry);
}
dput(dentry);
}
drop_nlink(d_inode(fuse_control_sb->s_root));

View file

@ -48,6 +48,7 @@
#include <linux/stat.h>
#include <linux/module.h>
#include <linux/uio.h>
#include <linux/user_namespace.h>
#include "fuse_i.h"
@ -406,7 +407,7 @@ err_unlock:
err_region:
unregister_chrdev_region(devt, 1);
err:
fuse_abort_conn(fc);
fuse_abort_conn(fc, false);
goto out;
}
@ -498,7 +499,11 @@ static int cuse_channel_open(struct inode *inode, struct file *file)
if (!cc)
return -ENOMEM;
fuse_conn_init(&cc->fc);
/*
* Limit the cuse channel to requests that can
* be represented in file->f_cred->user_ns.
*/
fuse_conn_init(&cc->fc, file->f_cred->user_ns);
fud = fuse_dev_alloc(&cc->fc);
if (!fud) {
@ -581,7 +586,7 @@ static ssize_t cuse_class_abort_store(struct device *dev,
{
struct cuse_conn *cc = dev_get_drvdata(dev);
fuse_abort_conn(&cc->fc);
fuse_abort_conn(&cc->fc, false);
return count;
}
static DEVICE_ATTR(abort, 0200, NULL, cuse_class_abort_store);

View file

@ -112,13 +112,6 @@ static void __fuse_put_request(struct fuse_req *req)
refcount_dec(&req->count);
}
static void fuse_req_init_context(struct fuse_conn *fc, struct fuse_req *req)
{
req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid());
req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid());
req->in.h.pid = pid_nr_ns(task_pid(current), fc->pid_ns);
}
void fuse_set_initialized(struct fuse_conn *fc)
{
/* Make sure stores before this are seen on another CPU */
@ -163,11 +156,19 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
goto out;
}
fuse_req_init_context(fc, req);
req->in.h.uid = from_kuid(fc->user_ns, current_fsuid());
req->in.h.gid = from_kgid(fc->user_ns, current_fsgid());
req->in.h.pid = pid_nr_ns(task_pid(current), fc->pid_ns);
__set_bit(FR_WAITING, &req->flags);
if (for_background)
__set_bit(FR_BACKGROUND, &req->flags);
if (unlikely(req->in.h.uid == ((uid_t)-1) ||
req->in.h.gid == ((gid_t)-1))) {
fuse_put_request(fc, req);
return ERR_PTR(-EOVERFLOW);
}
return req;
out:
@ -256,7 +257,10 @@ struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
if (!req)
req = get_reserved_req(fc, file);
fuse_req_init_context(fc, req);
req->in.h.uid = from_kuid_munged(fc->user_ns, current_fsuid());
req->in.h.gid = from_kgid_munged(fc->user_ns, current_fsgid());
req->in.h.pid = pid_nr_ns(task_pid(current), fc->pid_ns);
__set_bit(FR_WAITING, &req->flags);
__clear_bit(FR_BACKGROUND, &req->flags);
return req;
@ -381,8 +385,7 @@ static void request_end(struct fuse_conn *fc, struct fuse_req *req)
if (!fc->blocked && waitqueue_active(&fc->blocked_waitq))
wake_up(&fc->blocked_waitq);
if (fc->num_background == fc->congestion_threshold &&
fc->connected && fc->sb) {
if (fc->num_background == fc->congestion_threshold && fc->sb) {
clear_bdi_congested(fc->sb->s_bdi, BLK_RW_SYNC);
clear_bdi_congested(fc->sb->s_bdi, BLK_RW_ASYNC);
}
@ -1234,9 +1237,10 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
if (err)
goto err_unlock;
err = -ENODEV;
if (!fiq->connected)
if (!fiq->connected) {
err = (fc->aborted && fc->abort_err) ? -ECONNABORTED : -ENODEV;
goto err_unlock;
}
if (!list_empty(&fiq->interrupts)) {
req = list_entry(fiq->interrupts.next, struct fuse_req,
@ -1260,12 +1264,6 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
in = &req->in;
reqsize = in->h.len;
if (task_active_pid_ns(current) != fc->pid_ns) {
rcu_read_lock();
in->h.pid = pid_vnr(find_pid_ns(in->h.pid, fc->pid_ns));
rcu_read_unlock();
}
/* If request is too large, reply with an error and restart the read */
if (nbytes < reqsize) {
req->out.h.error = -EIO;
@ -1287,7 +1285,7 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
spin_lock(&fpq->lock);
clear_bit(FR_LOCKED, &req->flags);
if (!fpq->connected) {
err = -ENODEV;
err = (fc->aborted && fc->abort_err) ? -ECONNABORTED : -ENODEV;
goto out_end;
}
if (err) {
@ -2076,7 +2074,7 @@ static void end_polls(struct fuse_conn *fc)
* is OK, the request will in that case be removed from the list before we touch
* it.
*/
void fuse_abort_conn(struct fuse_conn *fc)
void fuse_abort_conn(struct fuse_conn *fc, bool is_abort)
{
struct fuse_iqueue *fiq = &fc->iq;
@ -2089,6 +2087,7 @@ void fuse_abort_conn(struct fuse_conn *fc)
fc->connected = 0;
fc->blocked = 0;
fc->aborted = is_abort;
fuse_set_initialized(fc);
list_for_each_entry(fud, &fc->devices, entry) {
struct fuse_pqueue *fpq = &fud->pq;
@ -2151,7 +2150,7 @@ int fuse_dev_release(struct inode *inode, struct file *file)
/* Are we the last open device? */
if (atomic_dec_and_test(&fc->dev_count)) {
WARN_ON(fc->iq.fasync != NULL);
fuse_abort_conn(fc);
fuse_abort_conn(fc, false);
}
fuse_dev_free(fud);
}

View file

@ -858,8 +858,8 @@ static void fuse_fillattr(struct inode *inode, struct fuse_attr *attr,
stat->ino = attr->ino;
stat->mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
stat->nlink = attr->nlink;
stat->uid = make_kuid(&init_user_ns, attr->uid);
stat->gid = make_kgid(&init_user_ns, attr->gid);
stat->uid = make_kuid(fc->user_ns, attr->uid);
stat->gid = make_kgid(fc->user_ns, attr->gid);
stat->rdev = inode->i_rdev;
stat->atime.tv_sec = attr->atime;
stat->atime.tv_nsec = attr->atimensec;
@ -924,12 +924,20 @@ static int fuse_do_getattr(struct inode *inode, struct kstat *stat,
}
static int fuse_update_get_attr(struct inode *inode, struct file *file,
struct kstat *stat)
struct kstat *stat, unsigned int flags)
{
struct fuse_inode *fi = get_fuse_inode(inode);
int err = 0;
bool sync;
if (time_before64(fi->i_time, get_jiffies_64())) {
if (flags & AT_STATX_FORCE_SYNC)
sync = true;
else if (flags & AT_STATX_DONT_SYNC)
sync = false;
else
sync = time_before64(fi->i_time, get_jiffies_64());
if (sync) {
forget_all_cached_acls(inode);
err = fuse_do_getattr(inode, stat, file);
} else if (stat) {
@ -943,7 +951,7 @@ static int fuse_update_get_attr(struct inode *inode, struct file *file,
int fuse_update_attributes(struct inode *inode, struct file *file)
{
return fuse_update_get_attr(inode, file, NULL);
return fuse_update_get_attr(inode, file, NULL, 0);
}
int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
@ -1030,7 +1038,7 @@ int fuse_allow_current_process(struct fuse_conn *fc)
const struct cred *cred;
if (fc->allow_other)
return 1;
return current_in_userns(fc->user_ns);
cred = current_cred();
if (uid_eq(cred->euid, fc->user_id) &&
@ -1475,17 +1483,17 @@ static bool update_mtime(unsigned ivalid, bool trust_local_mtime)
return true;
}
static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg,
bool trust_local_cmtime)
static void iattr_to_fattr(struct fuse_conn *fc, struct iattr *iattr,
struct fuse_setattr_in *arg, bool trust_local_cmtime)
{
unsigned ivalid = iattr->ia_valid;
if (ivalid & ATTR_MODE)
arg->valid |= FATTR_MODE, arg->mode = iattr->ia_mode;
if (ivalid & ATTR_UID)
arg->valid |= FATTR_UID, arg->uid = from_kuid(&init_user_ns, iattr->ia_uid);
arg->valid |= FATTR_UID, arg->uid = from_kuid(fc->user_ns, iattr->ia_uid);
if (ivalid & ATTR_GID)
arg->valid |= FATTR_GID, arg->gid = from_kgid(&init_user_ns, iattr->ia_gid);
arg->valid |= FATTR_GID, arg->gid = from_kgid(fc->user_ns, iattr->ia_gid);
if (ivalid & ATTR_SIZE)
arg->valid |= FATTR_SIZE, arg->size = iattr->ia_size;
if (ivalid & ATTR_ATIME) {
@ -1629,8 +1637,19 @@ int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
return err;
if (attr->ia_valid & ATTR_OPEN) {
if (fc->atomic_o_trunc)
/* This is coming from open(..., ... | O_TRUNC); */
WARN_ON(!(attr->ia_valid & ATTR_SIZE));
WARN_ON(attr->ia_size != 0);
if (fc->atomic_o_trunc) {
/*
* No need to send request to userspace, since actual
* truncation has already been done by OPEN. But still
* need to truncate page cache.
*/
i_size_write(inode, 0);
truncate_pagecache(inode, 0);
return 0;
}
file = NULL;
}
@ -1646,7 +1665,7 @@ int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
memset(&inarg, 0, sizeof(inarg));
memset(&outarg, 0, sizeof(outarg));
iattr_to_fattr(attr, &inarg, trust_local_cmtime);
iattr_to_fattr(fc, attr, &inarg, trust_local_cmtime);
if (file) {
struct fuse_file *ff = file->private_data;
inarg.valid |= FATTR_FH;
@ -1783,7 +1802,7 @@ static int fuse_getattr(const struct path *path, struct kstat *stat,
if (!fuse_allow_current_process(fc))
return -EACCES;
return fuse_update_get_attr(inode, NULL, stat);
return fuse_update_get_attr(inode, NULL, stat, flags);
}
static const struct inode_operations fuse_dir_inode_operations = {

View file

@ -26,6 +26,7 @@
#include <linux/xattr.h>
#include <linux/pid_namespace.h>
#include <linux/refcount.h>
#include <linux/user_namespace.h>
/** Max number of pages that can be used in a single read request */
#define FUSE_MAX_PAGES_PER_REQ 32
@ -466,6 +467,9 @@ struct fuse_conn {
/** The pid namespace for this mount */
struct pid_namespace *pid_ns;
/** The user namespace for this mount */
struct user_namespace *user_ns;
/** Maximum read size */
unsigned max_read;
@ -515,6 +519,9 @@ struct fuse_conn {
abort and device release */
unsigned connected;
/** Connection aborted via sysfs */
bool aborted;
/** Connection failed (version mismatch). Cannot race with
setting other bitfields since it is only set once in INIT
reply, before any other request, and never cleared */
@ -526,6 +533,9 @@ struct fuse_conn {
/** Do readpages asynchronously? Only set in INIT */
unsigned async_read:1;
/** Return an unique read error after abort. Only set in INIT */
unsigned abort_err:1;
/** Do not send separate SETATTR request before open(O_TRUNC) */
unsigned atomic_o_trunc:1;
@ -851,7 +861,7 @@ void fuse_request_send_background_locked(struct fuse_conn *fc,
struct fuse_req *req);
/* Abort all requests */
void fuse_abort_conn(struct fuse_conn *fc);
void fuse_abort_conn(struct fuse_conn *fc, bool is_abort);
/**
* Invalidate inode attributes
@ -870,7 +880,7 @@ struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
/**
* Initialize fuse_conn
*/
void fuse_conn_init(struct fuse_conn *fc);
void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns);
/**
* Release reference to fuse_conn
@ -975,6 +985,7 @@ ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
int fuse_removexattr(struct inode *inode, const char *name);
extern const struct xattr_handler *fuse_xattr_handlers[];
extern const struct xattr_handler *fuse_acl_xattr_handlers[];
extern const struct xattr_handler *fuse_no_acl_xattr_handlers[];
struct posix_acl;
struct posix_acl *fuse_get_acl(struct inode *inode, int type);

View file

@ -171,8 +171,8 @@ void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
inode->i_ino = fuse_squash_ino(attr->ino);
inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
set_nlink(inode, attr->nlink);
inode->i_uid = make_kuid(&init_user_ns, attr->uid);
inode->i_gid = make_kgid(&init_user_ns, attr->gid);
inode->i_uid = make_kuid(fc->user_ns, attr->uid);
inode->i_gid = make_kgid(fc->user_ns, attr->gid);
inode->i_blocks = attr->blocks;
inode->i_atime.tv_sec = attr->atime;
inode->i_atime.tv_nsec = attr->atimensec;
@ -371,7 +371,7 @@ void fuse_unlock_inode(struct inode *inode)
static void fuse_umount_begin(struct super_block *sb)
{
fuse_abort_conn(get_fuse_conn_super(sb));
fuse_abort_conn(get_fuse_conn_super(sb), false);
}
static void fuse_send_destroy(struct fuse_conn *fc)
@ -393,7 +393,7 @@ static void fuse_put_super(struct super_block *sb)
fuse_send_destroy(fc);
fuse_abort_conn(fc);
fuse_abort_conn(fc, false);
mutex_lock(&fuse_mutex);
list_del(&fc->entry);
fuse_ctl_remove_conn(fc);
@ -477,7 +477,8 @@ static int fuse_match_uint(substring_t *s, unsigned int *res)
return err;
}
static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev,
struct user_namespace *user_ns)
{
char *p;
memset(d, 0, sizeof(struct fuse_mount_data));
@ -513,7 +514,7 @@ static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
case OPT_USER_ID:
if (fuse_match_uint(&args[0], &uv))
return 0;
d->user_id = make_kuid(current_user_ns(), uv);
d->user_id = make_kuid(user_ns, uv);
if (!uid_valid(d->user_id))
return 0;
d->user_id_present = 1;
@ -522,7 +523,7 @@ static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
case OPT_GROUP_ID:
if (fuse_match_uint(&args[0], &uv))
return 0;
d->group_id = make_kgid(current_user_ns(), uv);
d->group_id = make_kgid(user_ns, uv);
if (!gid_valid(d->group_id))
return 0;
d->group_id_present = 1;
@ -565,8 +566,8 @@ static int fuse_show_options(struct seq_file *m, struct dentry *root)
struct super_block *sb = root->d_sb;
struct fuse_conn *fc = get_fuse_conn_super(sb);
seq_printf(m, ",user_id=%u", from_kuid_munged(&init_user_ns, fc->user_id));
seq_printf(m, ",group_id=%u", from_kgid_munged(&init_user_ns, fc->group_id));
seq_printf(m, ",user_id=%u", from_kuid_munged(fc->user_ns, fc->user_id));
seq_printf(m, ",group_id=%u", from_kgid_munged(fc->user_ns, fc->group_id));
if (fc->default_permissions)
seq_puts(m, ",default_permissions");
if (fc->allow_other)
@ -597,7 +598,7 @@ static void fuse_pqueue_init(struct fuse_pqueue *fpq)
fpq->connected = 1;
}
void fuse_conn_init(struct fuse_conn *fc)
void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns)
{
memset(fc, 0, sizeof(*fc));
spin_lock_init(&fc->lock);
@ -621,6 +622,7 @@ void fuse_conn_init(struct fuse_conn *fc)
fc->attr_version = 1;
get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
fc->pid_ns = get_pid_ns(task_active_pid_ns(current));
fc->user_ns = get_user_ns(user_ns);
}
EXPORT_SYMBOL_GPL(fuse_conn_init);
@ -630,6 +632,7 @@ void fuse_conn_put(struct fuse_conn *fc)
if (fc->destroy_req)
fuse_request_free(fc->destroy_req);
put_pid_ns(fc->pid_ns);
put_user_ns(fc->user_ns);
fc->release(fc);
}
}
@ -918,6 +921,8 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
fc->posix_acl = 1;
fc->sb->s_xattr = fuse_acl_xattr_handlers;
}
if (arg->flags & FUSE_ABORT_ERROR)
fc->abort_err = 1;
} else {
ra_pages = fc->max_read / PAGE_SIZE;
fc->no_lock = 1;
@ -948,7 +953,8 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT |
FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL;
FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL |
FUSE_ABORT_ERROR;
req->in.h.opcode = FUSE_INIT;
req->in.numargs = 1;
req->in.args[0].size = sizeof(*arg);
@ -1061,7 +1067,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION);
if (!parse_fuse_opt(data, &d, is_bdev))
if (!parse_fuse_opt(data, &d, is_bdev, sb->s_user_ns))
goto err;
if (is_bdev) {
@ -1089,16 +1095,27 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
if (!file)
goto err;
if ((file->f_op != &fuse_dev_operations) ||
(file->f_cred->user_ns != &init_user_ns))
/*
* Require mount to happen from the same user namespace which
* opened /dev/fuse to prevent potential attacks.
*/
if (file->f_op != &fuse_dev_operations ||
file->f_cred->user_ns != sb->s_user_ns)
goto err_fput;
/*
* If we are not in the initial user namespace posix
* acls must be translated.
*/
if (sb->s_user_ns != &init_user_ns)
sb->s_xattr = fuse_no_acl_xattr_handlers;
fc = kmalloc(sizeof(*fc), GFP_KERNEL);
err = -ENOMEM;
if (!fc)
goto err_fput;
fuse_conn_init(fc);
fuse_conn_init(fc, sb->s_user_ns);
fc->release = fuse_free_conn;
fud = fuse_dev_alloc(fc);
@ -1179,6 +1196,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
fuse_dev_free(fud);
err_put_conn:
fuse_conn_put(fc);
sb->s_fs_info = NULL;
err_fput:
fput(file);
err:
@ -1208,7 +1226,7 @@ static void fuse_kill_sb_anon(struct super_block *sb)
static struct file_system_type fuse_fs_type = {
.owner = THIS_MODULE,
.name = "fuse",
.fs_flags = FS_HAS_SUBTYPE,
.fs_flags = FS_HAS_SUBTYPE | FS_USERNS_MOUNT,
.mount = fuse_mount,
.kill_sb = fuse_kill_sb_anon,
};

View file

@ -192,6 +192,26 @@ static int fuse_xattr_set(const struct xattr_handler *handler,
return fuse_setxattr(inode, name, value, size, flags);
}
static bool no_xattr_list(struct dentry *dentry)
{
return false;
}
static int no_xattr_get(const struct xattr_handler *handler,
struct dentry *dentry, struct inode *inode,
const char *name, void *value, size_t size)
{
return -EOPNOTSUPP;
}
static int no_xattr_set(const struct xattr_handler *handler,
struct dentry *dentry, struct inode *nodee,
const char *name, const void *value,
size_t size, int flags)
{
return -EOPNOTSUPP;
}
static const struct xattr_handler fuse_xattr_handler = {
.prefix = "",
.get = fuse_xattr_get,
@ -209,3 +229,26 @@ const struct xattr_handler *fuse_acl_xattr_handlers[] = {
&fuse_xattr_handler,
NULL
};
static const struct xattr_handler fuse_no_acl_access_xattr_handler = {
.name = XATTR_NAME_POSIX_ACL_ACCESS,
.flags = ACL_TYPE_ACCESS,
.list = no_xattr_list,
.get = no_xattr_get,
.set = no_xattr_set,
};
static const struct xattr_handler fuse_no_acl_default_xattr_handler = {
.name = XATTR_NAME_POSIX_ACL_DEFAULT,
.flags = ACL_TYPE_ACCESS,
.list = no_xattr_list,
.get = no_xattr_get,
.set = no_xattr_set,
};
const struct xattr_handler *fuse_no_acl_xattr_handlers[] = {
&fuse_no_acl_access_xattr_handler,
&fuse_no_acl_default_xattr_handler,
&fuse_xattr_handler,
NULL
};