64 Commits
Author SHA1 Message Date
Miklos Szeredi e9bf38500e fuse: add refcount to fuse_dev
This will make it possible to grab the fuse_dev and subsequently release
the file that it came from.

In the above case, fud->fc will be set to FUSE_DEV_FC_DISCONNECTED to
indicate that this is no longer a functional device.

When trying to assign an fc to such a disconnected fuse_dev, the fc is set
to the disconnected state.

Use atomic operations xchg() and cmpxchg() to prevent races.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2026-04-02 20:43:24 +02:00
Linus Torvalds bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook 69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Miklos Szeredi dfb84c3307 fuse: allow synchronous FUSE_INIT
FUSE_INIT has always been asynchronous with mount.  That means that the
server processed this request after the mount syscall returned.

This means that FUSE_INIT can't supply the root inode's ID, hence it
currently has a hardcoded value.  There are other limitations such as not
being able to perform getxattr during mount, which is needed by selinux.

To remove these limitations allow server to process FUSE_INIT while
initializing the in-core super block for the fuse filesystem.  This can
only be done if the server is prepared to handle this, so add
FUSE_DEV_IOC_SYNC_INIT ioctl, which

 a) lets the server know whether this feature is supported, returning
 ENOTTY othewrwise.

 b) lets the kernel know to perform a synchronous initialization

The implementation is slightly tricky, since fuse_dev/fuse_conn are set up
only during super block creation.  This is solved by setting the private
data of the fuse device file to a special value ((struct fuse_dev *) 1) and
waiting for this to be turned into a proper fuse_dev before commecing with
operations on the device file.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2025-09-02 11:14:15 +02:00
Joanne KoongandMiklos Szeredi 68bfb7eb7f fuse: remove pages for requests and exclusively use folios
All fuse requests use folios instead of pages for transferring data.
Remove pages from the requests and exclusively use folios.

No functional changes.

[SzM: rename back folio_descs -> descs, etc.]

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2024-11-05 14:08:35 +01:00
Joanne KoongandMiklos Szeredi ee80369a8a fuse: convert cuse to use folios
Convert cuse requests to use a folio instead of a page.

No functional changes.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2024-11-05 11:14:32 +01:00
Yang LiandMiklos Szeredi 09492cb451 cuse: add kernel-doc comments to cuse_process_init_reply()
This commit adds kernel-doc style comments with complete parameter
descriptions for the function  cuse_process_init_reply.

Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2024-04-15 11:02:10 +02:00
Al Viro 053fc4f755 fuse: fix UAF in rcu pathwalks
->permission(), ->get_link() and ->inode_get_acl() might dereference
->s_fs_info (and, in case of ->permission(), ->s_fs_info->fc->user_ns
as well) when called from rcu pathwalk.

Freeing ->s_fs_info->fc is rcu-delayed; we need to make freeing ->s_fs_info
and dropping ->user_ns rcu-delayed too.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-02-25 02:10:32 -05:00
Greg Kroah-Hartman 1aaba11da9 driver core: class: remove module * from class_create()
The module pointer in class_create() never actually did anything, and it
shouldn't have been requred to be set as a parameter even if it did
something.  So just remove it and fix up all callers of the function in
the kernel tree at the same time.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17 15:16:33 +01:00
Randy DunlapandMiklos Szeredi 06bbb761c1 fuse: fix all W=1 kernel-doc warnings
Use correct function name in kernel-doc notation. (1)
Don't use "/**" to begin non-kernel-doc comments. (3)

Fixes these warnings:

fs/fuse/cuse.c:272: warning: expecting prototype for cuse_parse_dev_info(). Prototype was for cuse_parse_devinfo() instead
fs/fuse/dev.c:212: warning: expecting prototype for A new request is available, wake fiq(). Prototype was for fuse_dev_wake_and_unlock() instead
fs/fuse/dir.c:149: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Mark the attributes as stale due to an atime change.  Avoid the invalidate if
fs/fuse/file.c:656: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * In case of short read, the caller sets 'pos' to the position of

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2023-01-26 17:10:58 +01:00
ye xingchenandMiklos Szeredi e2283a7366 fuse: remove the unneeded result variable
Return the value fuse_dev_release() directly instead of storing it in
another redundant variable.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-11-23 09:10:49 +01:00
Miklos Szeredi 3c9c14338c cuse: simplify refcount
Put extra reference early in cuse_channel_open().

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2021-04-14 10:40:58 +02:00
Miklos Szeredi 8217673d07 cuse: prevent clone
For cloned connections cuse_channel_release() will be called more than
once, resulting in use after free.

Prevent device cloning for CUSE, which does not make sense at this point,
and highly unlikely to be used in real life.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2021-04-14 10:40:58 +02:00
Max ReitzandMiklos Szeredi fcee216beb fuse: split fuse_mount off of fuse_conn
We want to allow submounts for the same fuse_conn, but with different
superblocks so that each of the submounts has its own device ID.  To do
so, we need to split all mount-specific information off of fuse_conn
into a new fuse_mount structure, so that multiple mounts can share a
single fuse_conn.

We need to take care only to perform connection-level actions once (i.e.
when the fuse_conn and thus the first fuse_mount are established, or
when the last fuse_mount and thus the fuse_conn are destroyed).  For
example, fuse_sb_destroy() must invoke fuse_send_destroy() until the
last superblock is released.

To do so, we keep track of which fuse_mount is the root mount and
perform all fuse_conn-level actions only when this fuse_mount is
involved.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-18 15:17:41 +02:00
Kees Cook 3f649ab728 treewide: Remove uninitialized_var() usage
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-16 12:35:15 -07:00
zhengbinandMiklos Szeredi cabdb4fa2f fuse: use true,false for bool variable
Fixes coccicheck warning:

fs/fuse/readdir.c:335:1-19: WARNING: Assignment of 0/1 to bool variable
fs/fuse/file.c:1398:2-19: WARNING: Assignment of 0/1 to bool variable
fs/fuse/file.c:1400:2-20: WARNING: Assignment of 0/1 to bool variable
fs/fuse/cuse.c:454:1-20: WARNING: Assignment of 0/1 to bool variable
fs/fuse/cuse.c:455:1-19: WARNING: Assignment of 0/1 to bool variable
fs/fuse/inode.c:497:2-17: WARNING: Assignment of 0/1 to bool variable
fs/fuse/inode.c:504:2-23: WARNING: Assignment of 0/1 to bool variable
fs/fuse/inode.c:511:2-22: WARNING: Assignment of 0/1 to bool variable
fs/fuse/inode.c:518:2-23: WARNING: Assignment of 0/1 to bool variable
fs/fuse/inode.c:522:2-26: WARNING: Assignment of 0/1 to bool variable
fs/fuse/inode.c:526:2-18: WARNING: Assignment of 0/1 to bool variable
fs/fuse/inode.c:1000:1-20: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-02-06 16:39:28 +01:00
zhengbinandMiklos Szeredi 9ad09b1976 fuse: fix memleak in cuse_channel_open
If cuse_send_init fails, need to fuse_conn_put cc->fc.

cuse_channel_open->fuse_conn_init->refcount_set(&fc->count, 1)
                 ->fuse_dev_alloc->fuse_conn_get
                 ->fuse_dev_free->fuse_conn_put

Fixes: cc080e9e9b ("fuse: introduce per-instance fuse_dev structure")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-24 15:28:01 +02:00
Vivek GoyalandMiklos Szeredi 0cd1eb9a41 fuse: separate fuse device allocation and installation in fuse_conn
As of now fuse_dev_alloc() both allocates a fuse device and installs it in
fuse_conn list.  fuse_dev_alloc() can fail if fuse_device allocation fails.

virtio-fs needs to initialize multiple fuse devices (one per virtio queue).
It initializes one fuse device as part of call to fuse_fill_super_common()
and rest of the devices are allocated and installed after that.

But, we can't afford to fail after calling fuse_fill_super_common() as we
don't have a way to undo all the actions done by fuse_fill_super_common().
So to avoid failures after the call to fuse_fill_super_common(),
pre-allocate all fuse devices early and install them into fuse connection
later.

This patch provides two separate helpers for fuse device allocation and
fuse device installation in fuse_conn.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-12 14:59:41 +02:00
Stefan HajnocziandMiklos Szeredi ae3aad77f4 fuse: add fuse_iqueue_ops callbacks
The /dev/fuse device uses fiq->waitq and fasync to signal that requests are
available.  These mechanisms do not apply to virtio-fs.  This patch
introduces callbacks so alternative behavior can be used.

Note that queue_interrupt() changes along these lines:

  spin_lock(&fiq->waitq.lock);
  wake_up_locked(&fiq->waitq);
+ kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
  spin_unlock(&fiq->waitq.lock);
- kill_fasync(&fiq->fasync, SIGIO, POLL_IN);

Since queue_request() and queue_forget() also call kill_fasync() inside
the spinlock this should be safe.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-12 14:59:41 +02:00
Miklos Szeredi b50ef7c52a cuse: convert init to simple api
This is a straightforward conversion.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10 16:29:49 +02:00
Miklos Szeredi 56d250ef96 cuse: fix broken release
The inode parameter in cuse_release() is likely *not* a fuse inode.  It's a
small wonder it didn't blow up until now.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-02 11:07:30 +02:00
Thomas GleixnerandGreg Kroah-Hartman 55716d2643 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428
Based on 1 normalized pattern(s):

  this file is released under the gplv2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 68 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:16 +02:00
Kirill SmelkovandMiklos Szeredi f2294482ff fuse: convert printk -> pr_*
Functions, like pr_err, are a more modern variant of printing compared to
printk. They could be used to denoise sources by using needed level in
the print function name, and by automatically inserting per-driver /
function / ... print prefix as defined by pr_fmt macro. pr_* are also
said to be used in Documentation/process/coding-style.rst and more
recent code - for example overlayfs - uses them instead of printk.

Convert CUSE and FUSE to use the new pr_* functions.

CUSE output stays completely unchanged, while FUSE output is amended a
bit for "trying to steal weird page" warning - the second line now comes
also with "fuse:" prefix. I hope it is ok.

Suggested-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24 17:05:06 +02:00
Miklos Szeredi eb98e3bdf3 fuse: clean up aborted
The only caller that needs fc->aborted set is fuse_conn_abort_write().
Setting fc->aborted is now racy (fuse_abort_conn() may already be in
progress or finished) but there's no reason to care.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13 13:15:14 +01:00
Kirill TkhaiandMiklos Szeredi ebf84d0c72 fuse: Add fuse_inode argument to fuse_prepare_release()
Here is preparation for next patches, which introduce new fi->lock for
protection of ff->write_entry linked into fi->write_files.

This patch just passes new argument to the function.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13 13:15:13 +01:00