[00/29] const xattr tables

  From: Wedson Almeida Filho <walmeida@microsoft.com>

The 's_xattr' field of 'struct super_block' currently requires a mutable
table of 'struct xattr_handler' entries (although each handler itself is
const). However, no code in vfs actually modifies the tables.

So this series changes the type of 's_xattr' to allow const tables, and
modifies existing file system to move their tables to .rodata. This is
desirable because these tables contain entries with function pointers in
them; moving them to .rodata makes it considerably less likely to be
modified accidentally or maliciously at runtime.

I found this while writing Rust abstractions for vfs.

Wedson Almeida Filho (29):
  xattr: make the xattr array itself const
  ext4: move ext4_xattr_handlers to .rodata
  9p: move xattr-related structs to .rodata
  afs: move afs_xattr_handlers to .rodata
  btrfs: move btrfs_xattr_handlers to .rodata
  ceph: move ceph_xattr_handlers to .rodata
  ecryptfs: move ecryptfs_xattr_handlers to .rodata
  erofs: move erofs_xattr_handlers and xattr_handler_map to .rodata
  ext2: move ext2_xattr_handlers and ext2_xattr_handler_map to .rodata
  f2fs: move f2fs_xattr_handlers and f2fs_xattr_handler_map to .rodata
  fuse: move fuse_xattr_handlers to .rodata
  gfs2: move gfs2_xattr_handlers_max to .rodata
  hfs: move hfs_xattr_handlers to .rodata
  hfsplus: move hfsplus_xattr_handlers to .rodata
  jffs2: move jffs2_xattr_handlers to .rodata
  jfs: move jfs_xattr_handlers to .rodata
  kernfs: move kernfs_xattr_handlers to .rodata
  nfs: move nfs4_xattr_handlers to .rodata
  ntfs3: move ntfs_xattr_handlers to .rodata
  ocfs2: move ocfs2_xattr_handlers and ocfs2_xattr_handler_map to
    .rodata
  orangefs: move orangefs_xattr_handlers to .rodata
  reiserfs: move reiserfs_xattr_handlers to .rodata
  smb: move cifs_xattr_handlers to .rodata
  squashfs: move squashfs_xattr_handlers to .rodata
  ubifs: move ubifs_xattr_handlers to .rodata
  xfs: move xfs_xattr_handlers to .rodata
  overlayfs: move xattr tables to .rodata
  shmem: move shmem_xattr_handlers to .rodata
  net: move sockfs_xattr_handlers to .rodata

 fs/9p/xattr.c                 | 8 ++++----
 fs/9p/xattr.h                 | 2 +-
 fs/afs/internal.h             | 2 +-
 fs/afs/xattr.c                | 2 +-
 fs/btrfs/xattr.c              | 2 +-
 fs/btrfs/xattr.h              | 2 +-
 fs/ceph/super.h               | 2 +-
 fs/ceph/xattr.c               | 2 +-
 fs/ecryptfs/ecryptfs_kernel.h | 2 +-
 fs/ecryptfs/inode.c           | 2 +-
 fs/erofs/xattr.c              | 2 +-
 fs/erofs/xattr.h              | 4 ++--
 fs/ext2/xattr.c               | 4 ++--
 fs/ext2/xattr.h               | 2 +-
 fs/ext4/xattr.c               | 2 +-
 fs/ext4/xattr.h               | 2 +-
 fs/f2fs/xattr.c               | 4 ++--
 fs/f2fs/xattr.h               | 2 +-
 fs/fuse/fuse_i.h              | 2 +-
 fs/fuse/xattr.c               | 2 +-
 fs/gfs2/super.h               | 4 ++--
 fs/gfs2/xattr.c               | 4 ++--
 fs/hfs/attr.c                 | 2 +-
 fs/hfs/hfs_fs.h               | 2 +-
 fs/hfsplus/xattr.c            | 2 +-
 fs/hfsplus/xattr.h            | 2 +-
 fs/jffs2/xattr.c              | 2 +-
 fs/jffs2/xattr.h              | 2 +-
 fs/jfs/jfs_xattr.h            | 2 +-
 fs/jfs/xattr.c                | 2 +-
 fs/kernfs/inode.c             | 2 +-
 fs/kernfs/kernfs-internal.h   | 2 +-
 fs/nfs/nfs.h                  | 2 +-
 fs/nfs/nfs4_fs.h              | 2 +-
 fs/nfs/nfs4proc.c             | 2 +-
 fs/ntfs3/ntfs_fs.h            | 2 +-
 fs/ntfs3/xattr.c              | 2 +-
 fs/ocfs2/xattr.c              | 4 ++--
 fs/ocfs2/xattr.h              | 2 +-
 fs/orangefs/orangefs-kernel.h | 2 +-
 fs/orangefs/xattr.c           | 2 +-
 fs/overlayfs/super.c          | 4 ++--
 fs/reiserfs/reiserfs.h        | 2 +-
 fs/reiserfs/xattr.c           | 2 +-
 fs/smb/client/cifsfs.h        | 2 +-
 fs/smb/client/xattr.c         | 2 +-
 fs/squashfs/squashfs.h        | 2 +-
 fs/squashfs/xattr.c           | 2 +-
 fs/ubifs/ubifs.h              | 2 +-
 fs/ubifs/xattr.c              | 2 +-
 fs/xattr.c                    | 6 +++---
 fs/xfs/xfs_xattr.c            | 2 +-
 fs/xfs/xfs_xattr.h            | 2 +-
 include/linux/fs.h            | 2 +-
 include/linux/pseudo_fs.h     | 2 +-
 mm/shmem.c                    | 2 +-
 net/socket.c                  | 2 +-
 57 files changed, 69 insertions(+), 69 deletions(-)


base-commit: 2dde18cd1d8fac735875f2e4987f11817cc0bc2c
  

On Sat, Sep 30, 2023 at 02:00:04AM -0300, Wedson Almeida Filho wrote:
> From: Wedson Almeida Filho <walmeida@microsoft.com>
> 
> The 's_xattr' field of 'struct super_block' currently requires a mutable
> table of 'struct xattr_handler' entries (although each handler itself is
> const). However, no code in vfs actually modifies the tables.
> 
> So this series changes the type of 's_xattr' to allow const tables, and
> modifies existing file system to move their tables to .rodata. This is
> desirable because these tables contain entries with function pointers in
> them; moving them to .rodata makes it considerably less likely to be
> modified accidentally or maliciously at runtime.

Fine by me and good idea. On vacation this week but I'll wait for
individual fs maintainers to ack their portions anyway and then pick up
next week.
  

On Sat, Sep 30, 2023 at 02:00:04AM -0300, Wedson Almeida Filho wrote:
> From: Wedson Almeida Filho <walmeida@microsoft.com>
>
> The 's_xattr' field of 'struct super_block' currently requires a mutable
> table of 'struct xattr_handler' entries (although each handler itself is
> const). However, no code in vfs actually modifies the tables.
>
> So this series changes the type of 's_xattr' to allow const tables, and
> modifies existing file system to move their tables to .rodata. This is
> desirable because these tables contain entries with function pointers in
> them; moving them to .rodata makes it considerably less likely to be
> modified accidentally or maliciously at runtime.
>
> I found this while writing Rust abstractions for vfs.

Applied to the vfs.xattr branch of the vfs/vfs.git tree.
Patches in the vfs.xattr branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.xattr

[01/29] xattr: make the xattr array itself const
        https://git.kernel.org/vfs/vfs/c/e346fb6d774a
[02/29] ext4: move ext4_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/e60ac1283340
[03/29] 9p: move xattr-related structs to .rodata
        https://git.kernel.org/vfs/vfs/c/b6079dc9cb51
[04/29] afs: move afs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/f710c2e48135
[05/29] btrfs: move btrfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/8a25b4189896
[06/29] ceph: move ceph_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/10f9fbe9f25a
[07/29] ecryptfs: move ecryptfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/f354ed981066
[08/29] erofs: move erofs_xattr_handlers and xattr_handler_map to .rodata
        https://git.kernel.org/vfs/vfs/c/3591f40e223c
[09/29] ext2: move ext2_xattr_handlers and ext2_xattr_handler_map to .rodata
        https://git.kernel.org/vfs/vfs/c/ce78a1ec1c3b
[10/29] f2fs: move f2fs_xattr_handlers and f2fs_xattr_handler_map to .rodata
        https://git.kernel.org/vfs/vfs/c/a1c0752c33d2
[11/29] fuse: move fuse_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/34271edb1878
[12/29] gfs2: move gfs2_xattr_handlers_max to .rodata
        https://git.kernel.org/vfs/vfs/c/89491fafa81c
[13/29] hfs: move hfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/e27a45b65070
[14/29] hfsplus: move hfsplus_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/2c323f2c5650
[15/29] jffs2: move jffs2_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/13a75c3abcbe
[16/29] jfs: move jfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/ea780283e2c0
[17/29] kernfs: move kernfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/ffb2e0650827
[18/29] nfs: move nfs4_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/f496647e3b09
[19/29] ntfs3: move ntfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/5bf1dd9441da
[20/29] ocfs2: move ocfs2_xattr_handlers and ocfs2_xattr_handler_map to .rodata
        https://git.kernel.org/vfs/vfs/c/2cba9af99b3f
[21/29] orangefs: move orangefs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/2e9440ac0716
[22/29] reiserfs: move reiserfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/c063254b7de8
[23/29] smb: move cifs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/e45679b0d2e4
[24/29] squashfs: move squashfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/8a2ae79c7db0
[25/29] ubifs: move ubifs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/582f1ebe32a9
[26/29] xfs: move xfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/6fca42a3b168
[27/29] overlayfs: move xattr tables to .rodata
        https://git.kernel.org/vfs/vfs/c/3f644c1cd7b5
[28/29] shmem: move shmem_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/2f8e5f98045e
[29/29] net: move sockfs_xattr_handlers to .rodata
        https://git.kernel.org/vfs/vfs/c/dcff22588d9a