[v4,3/3] fs: introduce getfsxattrat and setfsxattrat syscalls

Commit Message

Andrey Albershteyn March 21, 2025, 7:48 p.m. UTC

From: Andrey Albershteyn <[e-mail]>

Introduce getfsxattrat and setfsxattrat syscalls to manipulate inode
extended attributes/flags. The syscalls take parent directory fd and
path to the child together with struct fsxattr.

This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference
that file don't need to be open as we can reference it with a path
instead of fd. By having this we can manipulated inode extended
attributes not only on regular files but also on special ones. This
is not possible with FS_IOC_FSSETXATTR ioctl as with special files
we can not call ioctl() directly on the filesystem inode using fd.

This patch adds two new syscalls which allows userspace to get/set
extended inode attributes on special files by using parent directory
and a path - *at() like syscall.

CC: [e-mail]
CC: [e-mail]
CC: [e-mail]
Signed-off-by: Andrey Albershteyn <[e-mail]>
Acked-by: Arnd Bergmann <[e-mail]>
---
 arch/alpha/kernel/syscalls/syscall.tbl      |   2 +
 arch/arm/tools/syscall.tbl                  |   2 +
 arch/arm64/tools/syscall_32.tbl             |   2 +
 arch/m68k/kernel/syscalls/syscall.tbl       |   2 +
 arch/microblaze/kernel/syscalls/syscall.tbl |   2 +
 arch/mips/kernel/syscalls/syscall_n32.tbl   |   2 +
 arch/mips/kernel/syscalls/syscall_n64.tbl   |   2 +
 arch/mips/kernel/syscalls/syscall_o32.tbl   |   2 +
 arch/parisc/kernel/syscalls/syscall.tbl     |   2 +
 arch/powerpc/kernel/syscalls/syscall.tbl    |   2 +
 arch/s390/kernel/syscalls/syscall.tbl       |   2 +
 arch/sh/kernel/syscalls/syscall.tbl         |   2 +
 arch/sparc/kernel/syscalls/syscall.tbl      |   2 +
 arch/x86/entry/syscalls/syscall_32.tbl      |   2 +
 arch/x86/entry/syscalls/syscall_64.tbl      |   2 +
 arch/xtensa/kernel/syscalls/syscall.tbl     |   2 +
 fs/inode.c                                  | 130 ++++++++++++++++++++++++++++
 include/linux/syscalls.h                    |   6 ++
 include/uapi/asm-generic/unistd.h           |   8 +-
 include/uapi/linux/fs.h                     |   3 +
 20 files changed, 178 insertions(+), 1 deletion(-)

Comments

Amir Goldstein March 23, 2025, 8:56 a.m. UTC | #1

On Fri, Mar 21, 2025 at 8:49 PM Andrey Albershteyn <[e-mail]> wrote:
>
> From: Andrey Albershteyn <[e-mail]>
>
> Introduce getfsxattrat and setfsxattrat syscalls to manipulate inode
> extended attributes/flags. The syscalls take parent directory fd and
> path to the child together with struct fsxattr.
>
> This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference
> that file don't need to be open as we can reference it with a path
> instead of fd. By having this we can manipulated inode extended
> attributes not only on regular files but also on special ones. This
> is not possible with FS_IOC_FSSETXATTR ioctl as with special files
> we can not call ioctl() directly on the filesystem inode using fd.
>
> This patch adds two new syscalls which allows userspace to get/set
> extended inode attributes on special files by using parent directory
> and a path - *at() like syscall.
>
> CC: [e-mail]
> CC: [e-mail]
> CC: [e-mail]
> Signed-off-by: Andrey Albershteyn <[e-mail]>
> Acked-by: Arnd Bergmann <[e-mail]>
> ---
...
> +SYSCALL_DEFINE5(setfsxattrat, int, dfd, const char __user *, filename,
> +               struct fsxattr __user *, ufsx, size_t, usize,
> +               unsigned int, at_flags)
> +{
> +       struct fileattr fa;
> +       struct path filepath;
> +       int error;
> +       unsigned int lookup_flags = 0;
> +       struct filename *name;
> +       struct mnt_idmap *idmap;.

> +       struct dentry *dentry;
> +       struct vfsmount *mnt;
> +       struct fsxattr fsx = {};
> +
> +       BUILD_BUG_ON(sizeof(struct fsxattr) < FSXATTR_SIZE_VER0);
> +       BUILD_BUG_ON(sizeof(struct fsxattr) != FSXATTR_SIZE_LATEST);
> +
> +       if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
> +               return -EINVAL;
> +
> +       if (!(at_flags & AT_SYMLINK_NOFOLLOW))
> +               lookup_flags |= LOOKUP_FOLLOW;
> +
> +       if (at_flags & AT_EMPTY_PATH)
> +               lookup_flags |= LOOKUP_EMPTY;
> +
> +       if (usize > PAGE_SIZE)
> +               return -E2BIG;
> +
> +       if (usize < FSXATTR_SIZE_VER0)
> +               return -EINVAL;
> +
> +       error = copy_struct_from_user(&fsx, sizeof(struct fsxattr), ufsx, usize);
> +       if (error)
> +               return error;
> +
> +       fsxattr_to_fileattr(&fsx, &fa);
> +
> +       name = getname_maybe_null(filename, at_flags);
> +       if (!name) {
> +               CLASS(fd, f)(dfd);
> +
> +               if (fd_empty(f))
> +                       return -EBADF;
> +
> +               idmap = file_mnt_idmap(fd_file(f));
> +               dentry = file_dentry(fd_file(f));
> +               mnt = fd_file(f)->f_path.mnt;
> +       } else {
> +               error = filename_lookup(dfd, name, lookup_flags, &filepath,
> +                                       NULL);
> +               if (error)
> +                       return error;
> +
> +               idmap = mnt_idmap(filepath.mnt);
> +               dentry = filepath.dentry;
> +               mnt = filepath.mnt;
> +       }
> +
> +       error = mnt_want_write(mnt);
> +       if (!error) {
> +               error = vfs_fileattr_set(idmap, dentry, &fa);
> +               if (error == -ENOIOCTLCMD)
> +                       error = -EOPNOTSUPP;

This is awkward.
vfs_fileattr_set() should return -EOPNOTSUPP.
ioctl_setflags() could maybe convert it to -ENOIOCTLCMD,
but looking at similar cases ioctl_fiemap(), ioctl_fsfreeze() the
ioctl returns -EOPNOTSUPP.

I don't think it is necessarily a bad idea to start returning
 -EOPNOTSUPP instead of -ENOIOCTLCMD for the ioctl
because that really reflects the fact that the ioctl is now implemented
in vfs and not in the specific fs.

and I think it would not be a bad idea at all to make that change
together with the merge of the syscalls as a sort of hint to userspace
that uses the ioctl, that the sycalls API exists.

Thanks,
Amir.

Andrey Albershteyn March 27, 2025, 9:33 a.m. UTC | #2

On 2025-03-23 09:56:25, Amir Goldstein wrote:
> On Fri, Mar 21, 2025 at 8:49 PM Andrey Albershteyn <[e-mail]> wrote:
> >
> > From: Andrey Albershteyn <[e-mail]>
> >
> > Introduce getfsxattrat and setfsxattrat syscalls to manipulate inode
> > extended attributes/flags. The syscalls take parent directory fd and
> > path to the child together with struct fsxattr.
> >
> > This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference
> > that file don't need to be open as we can reference it with a path
> > instead of fd. By having this we can manipulated inode extended
> > attributes not only on regular files but also on special ones. This
> > is not possible with FS_IOC_FSSETXATTR ioctl as with special files
> > we can not call ioctl() directly on the filesystem inode using fd.
> >
> > This patch adds two new syscalls which allows userspace to get/set
> > extended inode attributes on special files by using parent directory
> > and a path - *at() like syscall.
> >
> > CC: [e-mail]
> > CC: [e-mail]
> > CC: [e-mail]
> > Signed-off-by: Andrey Albershteyn <[e-mail]>
> > Acked-by: Arnd Bergmann <[e-mail]>
> > ---
> ...
> > +SYSCALL_DEFINE5(setfsxattrat, int, dfd, const char __user *, filename,
> > +               struct fsxattr __user *, ufsx, size_t, usize,
> > +               unsigned int, at_flags)
> > +{
> > +       struct fileattr fa;
> > +       struct path filepath;
> > +       int error;
> > +       unsigned int lookup_flags = 0;
> > +       struct filename *name;
> > +       struct mnt_idmap *idmap;.
> 
> > +       struct dentry *dentry;
> > +       struct vfsmount *mnt;
> > +       struct fsxattr fsx = {};
> > +
> > +       BUILD_BUG_ON(sizeof(struct fsxattr) < FSXATTR_SIZE_VER0);
> > +       BUILD_BUG_ON(sizeof(struct fsxattr) != FSXATTR_SIZE_LATEST);
> > +
> > +       if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
> > +               return -EINVAL;
> > +
> > +       if (!(at_flags & AT_SYMLINK_NOFOLLOW))
> > +               lookup_flags |= LOOKUP_FOLLOW;
> > +
> > +       if (at_flags & AT_EMPTY_PATH)
> > +               lookup_flags |= LOOKUP_EMPTY;
> > +
> > +       if (usize > PAGE_SIZE)
> > +               return -E2BIG;
> > +
> > +       if (usize < FSXATTR_SIZE_VER0)
> > +               return -EINVAL;
> > +
> > +       error = copy_struct_from_user(&fsx, sizeof(struct fsxattr), ufsx, usize);
> > +       if (error)
> > +               return error;
> > +
> > +       fsxattr_to_fileattr(&fsx, &fa);
> > +
> > +       name = getname_maybe_null(filename, at_flags);
> > +       if (!name) {
> > +               CLASS(fd, f)(dfd);
> > +
> > +               if (fd_empty(f))
> > +                       return -EBADF;
> > +
> > +               idmap = file_mnt_idmap(fd_file(f));
> > +               dentry = file_dentry(fd_file(f));
> > +               mnt = fd_file(f)->f_path.mnt;
> > +       } else {
> > +               error = filename_lookup(dfd, name, lookup_flags, &filepath,
> > +                                       NULL);
> > +               if (error)
> > +                       return error;
> > +
> > +               idmap = mnt_idmap(filepath.mnt);
> > +               dentry = filepath.dentry;
> > +               mnt = filepath.mnt;
> > +       }
> > +
> > +       error = mnt_want_write(mnt);
> > +       if (!error) {
> > +               error = vfs_fileattr_set(idmap, dentry, &fa);
> > +               if (error == -ENOIOCTLCMD)
> > +                       error = -EOPNOTSUPP;
> 
> This is awkward.
> vfs_fileattr_set() should return -EOPNOTSUPP.
> ioctl_setflags() could maybe convert it to -ENOIOCTLCMD,
> but looking at similar cases ioctl_fiemap(), ioctl_fsfreeze() the
> ioctl returns -EOPNOTSUPP.
> 
> I don't think it is necessarily a bad idea to start returning
>  -EOPNOTSUPP instead of -ENOIOCTLCMD for the ioctl
> because that really reflects the fact that the ioctl is now implemented
> in vfs and not in the specific fs.
> 
> and I think it would not be a bad idea at all to make that change
> together with the merge of the syscalls as a sort of hint to userspace
> that uses the ioctl, that the sycalls API exists.
> 
> Thanks,
> Amir.
> 

Hmm, not sure what you're suggesting here. I see it as:
- get/setfsxattrat should return EOPNOTSUPP as it make more sense
  than ENOIOCTLCMD
- ioctl_setflags returns ENOIOCTLCMD which also expected

Don't really see a reason to change what vfs_fileattr_set() returns
and then copying this if() to other places or start returning
EOPNOTSUPP.

Amir Goldstein March 27, 2025, 11:39 a.m. UTC | #3

On Thu, Mar 27, 2025 at 10:33 AM Andrey Albershteyn <[e-mail]> wrote:
>
> On 2025-03-23 09:56:25, Amir Goldstein wrote:
> > On Fri, Mar 21, 2025 at 8:49 PM Andrey Albershteyn <[e-mail]> wrote:
> > >
> > > From: Andrey Albershteyn <[e-mail]>
> > >
> > > Introduce getfsxattrat and setfsxattrat syscalls to manipulate inode
> > > extended attributes/flags. The syscalls take parent directory fd and
> > > path to the child together with struct fsxattr.
> > >
> > > This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference
> > > that file don't need to be open as we can reference it with a path
> > > instead of fd. By having this we can manipulated inode extended
> > > attributes not only on regular files but also on special ones. This
> > > is not possible with FS_IOC_FSSETXATTR ioctl as with special files
> > > we can not call ioctl() directly on the filesystem inode using fd.
> > >
> > > This patch adds two new syscalls which allows userspace to get/set
> > > extended inode attributes on special files by using parent directory
> > > and a path - *at() like syscall.
> > >
> > > CC: [e-mail]
> > > CC: [e-mail]
> > > CC: [e-mail]
> > > Signed-off-by: Andrey Albershteyn <[e-mail]>
> > > Acked-by: Arnd Bergmann <[e-mail]>
> > > ---
> > ...
> > > +SYSCALL_DEFINE5(setfsxattrat, int, dfd, const char __user *, filename,
> > > +               struct fsxattr __user *, ufsx, size_t, usize,
> > > +               unsigned int, at_flags)
> > > +{
> > > +       struct fileattr fa;
> > > +       struct path filepath;
> > > +       int error;
> > > +       unsigned int lookup_flags = 0;
> > > +       struct filename *name;
> > > +       struct mnt_idmap *idmap;.
> >
> > > +       struct dentry *dentry;
> > > +       struct vfsmount *mnt;
> > > +       struct fsxattr fsx = {};
> > > +
> > > +       BUILD_BUG_ON(sizeof(struct fsxattr) < FSXATTR_SIZE_VER0);
> > > +       BUILD_BUG_ON(sizeof(struct fsxattr) != FSXATTR_SIZE_LATEST);
> > > +
> > > +       if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
> > > +               return -EINVAL;
> > > +
> > > +       if (!(at_flags & AT_SYMLINK_NOFOLLOW))
> > > +               lookup_flags |= LOOKUP_FOLLOW;
> > > +
> > > +       if (at_flags & AT_EMPTY_PATH)
> > > +               lookup_flags |= LOOKUP_EMPTY;
> > > +
> > > +       if (usize > PAGE_SIZE)
> > > +               return -E2BIG;
> > > +
> > > +       if (usize < FSXATTR_SIZE_VER0)
> > > +               return -EINVAL;
> > > +
> > > +       error = copy_struct_from_user(&fsx, sizeof(struct fsxattr), ufsx, usize);
> > > +       if (error)
> > > +               return error;
> > > +
> > > +       fsxattr_to_fileattr(&fsx, &fa);
> > > +
> > > +       name = getname_maybe_null(filename, at_flags);
> > > +       if (!name) {
> > > +               CLASS(fd, f)(dfd);
> > > +
> > > +               if (fd_empty(f))
> > > +                       return -EBADF;
> > > +
> > > +               idmap = file_mnt_idmap(fd_file(f));
> > > +               dentry = file_dentry(fd_file(f));
> > > +               mnt = fd_file(f)->f_path.mnt;
> > > +       } else {
> > > +               error = filename_lookup(dfd, name, lookup_flags, &filepath,
> > > +                                       NULL);
> > > +               if (error)
> > > +                       return error;
> > > +
> > > +               idmap = mnt_idmap(filepath.mnt);
> > > +               dentry = filepath.dentry;
> > > +               mnt = filepath.mnt;
> > > +       }
> > > +
> > > +       error = mnt_want_write(mnt);
> > > +       if (!error) {
> > > +               error = vfs_fileattr_set(idmap, dentry, &fa);
> > > +               if (error == -ENOIOCTLCMD)
> > > +                       error = -EOPNOTSUPP;
> >
> > This is awkward.
> > vfs_fileattr_set() should return -EOPNOTSUPP.
> > ioctl_setflags() could maybe convert it to -ENOIOCTLCMD,
> > but looking at similar cases ioctl_fiemap(), ioctl_fsfreeze() the
> > ioctl returns -EOPNOTSUPP.
> >
> > I don't think it is necessarily a bad idea to start returning
> >  -EOPNOTSUPP instead of -ENOIOCTLCMD for the ioctl
> > because that really reflects the fact that the ioctl is now implemented
> > in vfs and not in the specific fs.
> >
> > and I think it would not be a bad idea at all to make that change
> > together with the merge of the syscalls as a sort of hint to userspace
> > that uses the ioctl, that the sycalls API exists.
> >
> > Thanks,
> > Amir.
> >
>
> Hmm, not sure what you're suggesting here. I see it as:
> - get/setfsxattrat should return EOPNOTSUPP as it make more sense
>   than ENOIOCTLCMD
> - ioctl_setflags returns ENOIOCTLCMD which also expected
>
> Don't really see a reason to change what vfs_fileattr_set() returns
> and then copying this if() to other places or start returning
> EOPNOTSUPP.

ENOIOCTLCMD conceptually means that the ioctl command is unknown
This is not the case since ->fileattr_[gs]et() became a vfs API
the ioctl command is handled by vfs and it is known, but individual
filesystems may not support it, so conceptually, returning EOPNOTSUPP
from ioctl() is more correct these days, exactly as is done with the ioctls
FS_IOC_FIEMAP and FIFREEZE which were also historically per fs
ioctls and made into a vfs API.

The fact that bcachefs does not implement ->fileattr_[gs]et() and does
implement FS_IOC_FS[GS]ETXATTR is an oversight IMO, since it
was probably merged after the vfs conversion patch.

This mistake means that bcachefs fileattr cannot be copied up by
ovl_copy_fileattr() which uses the vfs API and NOT the ioctl.

However, if you would made the internal vfs API change that I suggested,
it will have broken ovl_real_fileattr_get() and ovl_copy_fileattr(),
so leave it for now - if I care enough I can do it later together with
fixing the overlayfs and fuse code.

Thanks,
Amir.

Jan Kara March 27, 2025, 12:31 p.m. UTC | #4

On Fri 21-03-25 20:48:42, Andrey Albershteyn wrote:
> From: Andrey Albershteyn <[e-mail]>
> 
> Introduce getfsxattrat and setfsxattrat syscalls to manipulate inode
> extended attributes/flags. The syscalls take parent directory fd and
> path to the child together with struct fsxattr.
> 
> This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference
> that file don't need to be open as we can reference it with a path
> instead of fd. By having this we can manipulated inode extended
> attributes not only on regular files but also on special ones. This
> is not possible with FS_IOC_FSSETXATTR ioctl as with special files
> we can not call ioctl() directly on the filesystem inode using fd.
> 
> This patch adds two new syscalls which allows userspace to get/set
> extended inode attributes on special files by using parent directory
> and a path - *at() like syscall.
> 
> CC: [e-mail]
> CC: [e-mail]
> CC: [e-mail]
> Signed-off-by: Andrey Albershteyn <[e-mail]>
> Acked-by: Arnd Bergmann <[e-mail]>

Looks good. Just two nits below:

> +SYSCALL_DEFINE5(getfsxattrat, int, dfd, const char __user *, filename,
> +		struct fsxattr __user *, ufsx, size_t, usize,
> +		unsigned int, at_flags)
> +{
> +	struct fileattr fa = {};
> +	struct path filepath;
> +	int error;
> +	unsigned int lookup_flags = 0;
> +	struct filename *name;
> +	struct fsxattr fsx = {};
> +
> +	BUILD_BUG_ON(sizeof(struct fsxattr) < FSXATTR_SIZE_VER0);
> +	BUILD_BUG_ON(sizeof(struct fsxattr) != FSXATTR_SIZE_LATEST);
> +
> +	if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
> +		return -EINVAL;
> +
> +	if (!(at_flags & AT_SYMLINK_NOFOLLOW))
> +		lookup_flags |= LOOKUP_FOLLOW;
> +
> +	if (at_flags & AT_EMPTY_PATH)
> +		lookup_flags |= LOOKUP_EMPTY;

Strictly speaking setting LOOKUP_EMPTY does not have any effect because
empty names are already handled by getname_maybe_null(). But it does not
hurt either so I don't really care...

> +
> +	if (usize > PAGE_SIZE)
> +		return -E2BIG;
> +
> +	if (usize < FSXATTR_SIZE_VER0)
> +		return -EINVAL;
> +
> +	name = getname_maybe_null(filename, at_flags);
> +	if (!name) {
> +		CLASS(fd, f)(dfd);
> +
> +		if (fd_empty(f))
> +			return -EBADF;
> +		error = vfs_fileattr_get(file_dentry(fd_file(f)), &fa);
> +	} else {
> +		error = filename_lookup(dfd, name, lookup_flags, &filepath,
> +					NULL);
> +		if (error)
> +			goto out;
> +		error = vfs_fileattr_get(filepath.dentry, &fa);
> +		path_put(&filepath);
> +	}
> +	if (error == -ENOIOCTLCMD)
> +		error = -EOPNOTSUPP;
> +	if (!error) {
> +		fileattr_to_fsxattr(&fa, &fsx);
> +		error = copy_struct_to_user(ufsx, usize, &fsx,
> +					    sizeof(struct fsxattr), NULL);
> +	}
> +out:
> +	putname(name);
> +	return error;
> +}
> +
> +SYSCALL_DEFINE5(setfsxattrat, int, dfd, const char __user *, filename,
> +		struct fsxattr __user *, ufsx, size_t, usize,
> +		unsigned int, at_flags)
> +{
> +	struct fileattr fa;
> +	struct path filepath;
> +	int error;
> +	unsigned int lookup_flags = 0;
> +	struct filename *name;
> +	struct mnt_idmap *idmap;
> +	struct dentry *dentry;
> +	struct vfsmount *mnt;
> +	struct fsxattr fsx = {};
> +
> +	BUILD_BUG_ON(sizeof(struct fsxattr) < FSXATTR_SIZE_VER0);
> +	BUILD_BUG_ON(sizeof(struct fsxattr) != FSXATTR_SIZE_LATEST);
> +
> +	if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
> +		return -EINVAL;
> +
> +	if (!(at_flags & AT_SYMLINK_NOFOLLOW))
> +		lookup_flags |= LOOKUP_FOLLOW;
> +
> +	if (at_flags & AT_EMPTY_PATH)
> +		lookup_flags |= LOOKUP_EMPTY;

Same comment regarding LOOKUP_EMPTY here.

> +
> +	if (usize > PAGE_SIZE)
> +		return -E2BIG;
> +
> +	if (usize < FSXATTR_SIZE_VER0)
> +		return -EINVAL;
> +
> +	error = copy_struct_from_user(&fsx, sizeof(struct fsxattr), ufsx, usize);
> +	if (error)
> +		return error;
> +
> +	fsxattr_to_fileattr(&fsx, &fa);
> +
> +	name = getname_maybe_null(filename, at_flags);
> +	if (!name) {
> +		CLASS(fd, f)(dfd);
> +
> +		if (fd_empty(f))
> +			return -EBADF;
> +
> +		idmap = file_mnt_idmap(fd_file(f));
> +		dentry = file_dentry(fd_file(f));
> +		mnt = fd_file(f)->f_path.mnt;
> +	} else {
> +		error = filename_lookup(dfd, name, lookup_flags, &filepath,
> +					NULL);
> +		if (error)
> +			return error;
> +
> +		idmap = mnt_idmap(filepath.mnt);
> +		dentry = filepath.dentry;
> +		mnt = filepath.mnt;
> +	}
> +
> +	error = mnt_want_write(mnt);
> +	if (!error) {
> +		error = vfs_fileattr_set(idmap, dentry, &fa);
> +		if (error == -ENOIOCTLCMD)
> +			error = -EOPNOTSUPP;
> +		mnt_drop_write(mnt);
> +	}
> +
> +	path_put(&filepath);

filepath will not be initialized here in case of name == NULL. 

> +	return error;
> +}

With this fixed feel free to add:

Reviewed-by: Jan Kara <[e-mail]>

								Honza

Patch

diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index c59d53d6d3f3490f976ca179ddfe02e69265ae4d..4b9e687494c16b60c6fd6ca1dc4d6564706a7e25 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl
@@ -506,3 +506,5 @@ 
 574	common	getxattrat			sys_getxattrat
 575	common	listxattrat			sys_listxattrat
 576	common	removexattrat			sys_removexattrat
+577	common	getfsxattrat			sys_getfsxattrat
+578	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index 49eeb2ad8dbd8e074c6240417693f23fb328afa8..66466257f3c2debb3e2299f0b608c6740c98cab2 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -481,3 +481,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/arm64/tools/syscall_32.tbl b/arch/arm64/tools/syscall_32.tbl
index 69a829912a05eb8a3e21ed701d1030e31c0148bc..9c516118b154811d8d11d5696f32817430320dbf 100644
--- a/arch/arm64/tools/syscall_32.tbl
+++ b/arch/arm64/tools/syscall_32.tbl
@@ -478,3 +478,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index f5ed71f1910d09769c845c2d062d99ee0449437c..159476387f394a92ee5e29db89b118c630372db2 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl
@@ -466,3 +466,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index 680f568b77f2cbefc3eacb2517f276041f229b1e..a6d59ee740b58cacf823702003cf9bad17c0d3b7 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -472,3 +472,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index 0b9b7e25b69ad592642f8533bee9ccfe95ce9626..cfe38fcebe1a0279e11751378d3e71c5ec6b6569 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -405,3 +405,5 @@ 
 464	n32	getxattrat			sys_getxattrat
 465	n32	listxattrat			sys_listxattrat
 466	n32	removexattrat			sys_removexattrat
+467	n32	getfsxattrat			sys_getfsxattrat
+468	n32	setfsxattrat			sys_setfsxattrat
diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl
index c844cd5cda620b2809a397cdd6f4315ab6a1bfe2..29a0c5974d1aa2f01e33edc0252d75fb97abe230 100644
--- a/arch/mips/kernel/syscalls/syscall_n64.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n64.tbl
@@ -381,3 +381,5 @@ 
 464	n64	getxattrat			sys_getxattrat
 465	n64	listxattrat			sys_listxattrat
 466	n64	removexattrat			sys_removexattrat
+467	n64	getfsxattrat			sys_getfsxattrat
+468	n64	setfsxattrat			sys_setfsxattrat
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index 349b8aad1159f404103bd2057a1e64e9bf309f18..6c00436807c57c492ba957fcd59af1202231cf80 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -454,3 +454,5 @@ 
 464	o32	getxattrat			sys_getxattrat
 465	o32	listxattrat			sys_listxattrat
 466	o32	removexattrat			sys_removexattrat
+467	o32	getfsxattrat			sys_getfsxattrat
+468	o32	setfsxattrat			sys_setfsxattrat
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index d9fc94c869657fcfbd7aca1d5f5abc9fae2fb9d8..b3578fac43d6b65167787fcc97d2d09f5a9828e7 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -465,3 +465,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index d8b4ab78bef076bd50d49b87dea5060fd8c1686a..808045d82c9465c3bfa96b15947546efe5851e9a 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -557,3 +557,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index e9115b4d8b635b846e5c9ad6ce229605323723a5..78dfc2c184d4815baf8a9e61c546c9936d58a47c 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -469,3 +469,5 @@ 
 464  common	getxattrat		sys_getxattrat			sys_getxattrat
 465  common	listxattrat		sys_listxattrat			sys_listxattrat
 466  common	removexattrat		sys_removexattrat		sys_removexattrat
+467  common	getfsxattrat		sys_getfsxattrat		sys_getfsxattrat
+468  common	setfsxattrat		sys_setfsxattrat		sys_setfsxattrat
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index c8cad33bf250ea110de37bd1407f5a43ec5e38f2..d5a5c8339f0ed25ea07c4aba90351d352033c8a0 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl
@@ -470,3 +470,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index 727f99d333b304b3db0711953a3d91ece18a28eb..817dcd8603bcbffc47f3f59aa3b74b16486453d0 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl
@@ -512,3 +512,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 4d0fb2fba7e208ae9455459afe11e277321d9f74..b4842c027c5d00c0236b2ba89387c5e2267447bd 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -472,3 +472,5 @@ 
 464	i386	getxattrat		sys_getxattrat
 465	i386	listxattrat		sys_listxattrat
 466	i386	removexattrat		sys_removexattrat
+467	i386	getfsxattrat		sys_getfsxattrat
+468	i386	setfsxattrat		sys_setfsxattrat
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 5eb708bff1c791debd6cfc5322583b2ae53f6437..b6f0a7236aaee624cf9b484239a1068085a8ffe1 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -390,6 +390,8 @@ 
 464	common	getxattrat		sys_getxattrat
 465	common	listxattrat		sys_listxattrat
 466	common	removexattrat		sys_removexattrat
+467	common	getfsxattrat		sys_getfsxattrat
+468	common	setfsxattrat		sys_setfsxattrat
 
 #
 # Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index 37effc1b134eea061f2c350c1d68b4436b65a4dd..425d56be337d1de22f205ac503df61ff86224fee 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -437,3 +437,5 @@ 
 464	common	getxattrat			sys_getxattrat
 465	common	listxattrat			sys_listxattrat
 466	common	removexattrat			sys_removexattrat
+467	common	getfsxattrat			sys_getfsxattrat
+468	common	setfsxattrat			sys_setfsxattrat
diff --git a/fs/inode.c b/fs/inode.c
index 6b4c77268fc0ecace4ac78a9ca777fbffc277f4a..811debf379ab299f287ed90863277cfda27db30c 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -23,6 +23,9 @@ 
 #include <linux/rw_hint.h>
 #include <linux/seq_file.h>
 #include <linux/debugfs.h>
+#include <linux/syscalls.h>
+#include <linux/fileattr.h>
+#include <linux/namei.h>
 #include <trace/events/writeback.h>
 #define CREATE_TRACE_POINTS
 #include <trace/events/timestamp.h>
@@ -2953,3 +2956,130 @@  umode_t mode_strip_sgid(struct mnt_idmap *idmap,
 	return mode & ~S_ISGID;
 }
 EXPORT_SYMBOL(mode_strip_sgid);
+
+SYSCALL_DEFINE5(getfsxattrat, int, dfd, const char __user *, filename,
+		struct fsxattr __user *, ufsx, size_t, usize,
+		unsigned int, at_flags)
+{
+	struct fileattr fa = {};
+	struct path filepath;
+	int error;
+	unsigned int lookup_flags = 0;
+	struct filename *name;
+	struct fsxattr fsx = {};
+
+	BUILD_BUG_ON(sizeof(struct fsxattr) < FSXATTR_SIZE_VER0);
+	BUILD_BUG_ON(sizeof(struct fsxattr) != FSXATTR_SIZE_LATEST);
+
+	if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
+		return -EINVAL;
+
+	if (!(at_flags & AT_SYMLINK_NOFOLLOW))
+		lookup_flags |= LOOKUP_FOLLOW;
+
+	if (at_flags & AT_EMPTY_PATH)
+		lookup_flags |= LOOKUP_EMPTY;
+
+	if (usize > PAGE_SIZE)
+		return -E2BIG;
+
+	if (usize < FSXATTR_SIZE_VER0)
+		return -EINVAL;
+
+	name = getname_maybe_null(filename, at_flags);
+	if (!name) {
+		CLASS(fd, f)(dfd);
+
+		if (fd_empty(f))
+			return -EBADF;
+		error = vfs_fileattr_get(file_dentry(fd_file(f)), &fa);
+	} else {
+		error = filename_lookup(dfd, name, lookup_flags, &filepath,
+					NULL);
+		if (error)
+			goto out;
+		error = vfs_fileattr_get(filepath.dentry, &fa);
+		path_put(&filepath);
+	}
+	if (error == -ENOIOCTLCMD)
+		error = -EOPNOTSUPP;
+	if (!error) {
+		fileattr_to_fsxattr(&fa, &fsx);
+		error = copy_struct_to_user(ufsx, usize, &fsx,
+					    sizeof(struct fsxattr), NULL);
+	}
+out:
+	putname(name);
+	return error;
+}
+
+SYSCALL_DEFINE5(setfsxattrat, int, dfd, const char __user *, filename,
+		struct fsxattr __user *, ufsx, size_t, usize,
+		unsigned int, at_flags)
+{
+	struct fileattr fa;
+	struct path filepath;
+	int error;
+	unsigned int lookup_flags = 0;
+	struct filename *name;
+	struct mnt_idmap *idmap;
+	struct dentry *dentry;
+	struct vfsmount *mnt;
+	struct fsxattr fsx = {};
+
+	BUILD_BUG_ON(sizeof(struct fsxattr) < FSXATTR_SIZE_VER0);
+	BUILD_BUG_ON(sizeof(struct fsxattr) != FSXATTR_SIZE_LATEST);
+
+	if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
+		return -EINVAL;
+
+	if (!(at_flags & AT_SYMLINK_NOFOLLOW))
+		lookup_flags |= LOOKUP_FOLLOW;
+
+	if (at_flags & AT_EMPTY_PATH)
+		lookup_flags |= LOOKUP_EMPTY;
+
+	if (usize > PAGE_SIZE)
+		return -E2BIG;
+
+	if (usize < FSXATTR_SIZE_VER0)
+		return -EINVAL;
+
+	error = copy_struct_from_user(&fsx, sizeof(struct fsxattr), ufsx, usize);
+	if (error)
+		return error;
+
+	fsxattr_to_fileattr(&fsx, &fa);
+
+	name = getname_maybe_null(filename, at_flags);
+	if (!name) {
+		CLASS(fd, f)(dfd);
+
+		if (fd_empty(f))
+			return -EBADF;
+
+		idmap = file_mnt_idmap(fd_file(f));
+		dentry = file_dentry(fd_file(f));
+		mnt = fd_file(f)->f_path.mnt;
+	} else {
+		error = filename_lookup(dfd, name, lookup_flags, &filepath,
+					NULL);
+		if (error)
+			return error;
+
+		idmap = mnt_idmap(filepath.mnt);
+		dentry = filepath.dentry;
+		mnt = filepath.mnt;
+	}
+
+	error = mnt_want_write(mnt);
+	if (!error) {
+		error = vfs_fileattr_set(idmap, dentry, &fa);
+		if (error == -ENOIOCTLCMD)
+			error = -EOPNOTSUPP;
+		mnt_drop_write(mnt);
+	}
+
+	path_put(&filepath);
+	return error;
+}
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index c6333204d45130eb022f6db460eea34a1f6e91db..e242ea39b3e63a8008bc777764b616fd63bd40c4 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -371,6 +371,12 @@  asmlinkage long sys_removexattrat(int dfd, const char __user *path,
 asmlinkage long sys_lremovexattr(const char __user *path,
 				 const char __user *name);
 asmlinkage long sys_fremovexattr(int fd, const char __user *name);
+asmlinkage long sys_getfsxattrat(int dfd, const char __user *filename,
+				 struct fsxattr __user *ufsx, size_t usize,
+				 unsigned int at_flags);
+asmlinkage long sys_setfsxattrat(int dfd, const char __user *filename,
+				 struct fsxattr __user *ufsx, size_t usize,
+				 unsigned int at_flags);
 asmlinkage long sys_getcwd(char __user *buf, unsigned long size);
 asmlinkage long sys_eventfd2(unsigned int count, int flags);
 asmlinkage long sys_epoll_create1(int flags);
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 88dc393c2bca38c0fa1b3fae579f7cfe4931223c..50be2e1007bc2779120d05c6e9512a689f86779c 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -850,8 +850,14 @@  __SYSCALL(__NR_listxattrat, sys_listxattrat)
 #define __NR_removexattrat 466
 __SYSCALL(__NR_removexattrat, sys_removexattrat)
 
+/* fs/inode.c */
+#define __NR_getfsxattrat 467
+__SYSCALL(__NR_getfsxattrat, sys_getfsxattrat)
+#define __NR_setfsxattrat 468
+__SYSCALL(__NR_setfsxattrat, sys_setfsxattrat)
+
 #undef __NR_syscalls
-#define __NR_syscalls 467
+#define __NR_syscalls 469
 
 /*
  * 32 bit systems traditionally used different
diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
index 7539717707337a8cb22396a869baba3bafa08371..aed753e5d50c97da9b895a187fdaecf0477db74b 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -139,6 +139,9 @@  struct fsxattr {
 	unsigned char	fsx_pad[8];
 };
 
+#define FSXATTR_SIZE_VER0 28
+#define FSXATTR_SIZE_LATEST FSXATTR_SIZE_VER0
+
 /*
  * Flags for the fsx_xflags field
  */