A mount's idmapping is immutable. The only thing that is allowed to be modified afterwards is the reference count and that is hidden behind mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads from the idmapping. This is the same model that struct cred uses and the idmapping is also rather sensitive.
So make the idmap argument const wherever we can. The conversion is done from the bottom up so callers can continue to pass a non-const pointer to a const parameter until the conversion is finished. Signed-off-by: Christian Brauner (Amutable) <[email protected]> --- Christian Brauner (27): userns: pass const uid_gid_map in lookup helpers fs: port mnt_idmap_{get,put}() to const mnt_idmap fs: port vfs{g,u}id helpers to const mnt_idmap fs: port fs{g,u}id helpers to const mnt_idmap fs: port i_{g,u}id_into_vfs{g,u}id() to const mnt_idmap fs: port i_{g,u}id_{needs_}update() to const mnt_idmap quota: port to const mnt_idmap fs: port privilege checking helpers to const mnt_idmap fs: port inode_owner_or_capable() to const mnt_idmap fs: port inode_init_owner() to const mnt_idmap fs: port acl to const mnt_idmap fs: port ->permission() to pass const mnt_idmap fs: port xattr to const mnt_idmap fs: port ->fileattr_set() to pass const mnt_idmap fs: port ->set_acl() to pass const mnt_idmap fs: port ->get_acl() to pass const mnt_idmap fs: port ->tmpfile() to pass const mnt_idmap fs: port ->mknod() to pass const mnt_idmap fs: port ->rename() to pass const mnt_idmap fs: port ->mkdir() to pass const mnt_idmap fs: port ->symlink() to pass const mnt_idmap fs: port ->create() to pass const mnt_idmap fs: port ->getattr() to pass const mnt_idmap fs: port ->setattr() to pass const mnt_idmap fs: port vfs_*() helpers to const mnt_idmap fs: port mnt_idmap() and file_mnt_idmap() to const mnt_idmap fs: make nop_mnt_idmap and invalid_mnt_idmap const Documentation/filesystems/locking.rst | 24 +++---- Documentation/filesystems/porting.rst | 13 ++++ Documentation/filesystems/vfs.rst | 24 +++---- arch/powerpc/platforms/cell/spufs/inode.c | 2 +- drivers/android/binder/rust_binderfs.c | 2 +- drivers/android/binderfs.c | 2 +- fs/9p/acl.c | 4 +- fs/9p/acl.h | 4 +- fs/9p/v9fs.h | 2 +- fs/9p/v9fs_vfs.h | 2 +- fs/9p/vfs_inode.c | 14 ++-- fs/9p/vfs_inode_dotl.c | 14 ++-- fs/9p/xattr.c | 2 +- fs/adfs/adfs.h | 2 +- fs/adfs/inode.c | 2 +- fs/affs/affs.h | 10 +-- fs/affs/inode.c | 2 +- fs/affs/namei.c | 8 +-- fs/afs/dir.c | 16 ++--- fs/afs/inode.c | 4 +- fs/afs/internal.h | 6 +- fs/afs/security.c | 2 +- fs/afs/xattr.c | 4 +- fs/anon_inodes.c | 4 +- fs/attr.c | 16 ++--- fs/autofs/root.c | 12 ++-- fs/backing-file.c | 2 +- fs/bad_inode.c | 20 +++--- fs/bfs/dir.c | 4 +- fs/btrfs/acl.c | 2 +- fs/btrfs/acl.h | 2 +- fs/btrfs/btrfs_inode.h | 2 +- fs/btrfs/inode.c | 24 +++---- fs/btrfs/ioctl.c | 16 ++--- fs/btrfs/ioctl.h | 2 +- fs/btrfs/xattr.c | 6 +- fs/ceph/acl.c | 2 +- fs/ceph/dir.c | 10 +-- fs/ceph/file.c | 2 +- fs/ceph/inode.c | 10 +-- fs/ceph/mds_client.h | 2 +- fs/ceph/super.h | 10 +-- fs/ceph/xattr.c | 2 +- fs/coda/coda_linux.h | 6 +- fs/coda/dir.c | 10 +-- fs/coda/inode.c | 4 +- fs/coda/pioctl.c | 4 +- fs/configfs/configfs_internal.h | 4 +- fs/configfs/dir.c | 2 +- fs/configfs/inode.c | 2 +- fs/configfs/symlink.c | 2 +- fs/coredump.c | 2 +- fs/debugfs/inode.c | 2 +- fs/ecryptfs/inode.c | 26 +++---- fs/efivarfs/inode.c | 6 +- fs/erofs/inode.c | 2 +- fs/erofs/internal.h | 2 +- fs/exec.c | 4 +- fs/exfat/exfat_fs.h | 4 +- fs/exfat/file.c | 6 +- fs/exfat/namei.c | 6 +- fs/ext2/acl.c | 2 +- fs/ext2/acl.h | 2 +- fs/ext2/ext2.h | 6 +- fs/ext2/inode.c | 4 +- fs/ext2/ioctl.c | 2 +- fs/ext2/namei.c | 12 ++-- fs/ext2/xattr_security.c | 2 +- fs/ext2/xattr_trusted.c | 2 +- fs/ext2/xattr_user.c | 2 +- fs/ext4/acl.c | 2 +- fs/ext4/acl.h | 2 +- fs/ext4/ext4.h | 10 +-- fs/ext4/ialloc.c | 2 +- fs/ext4/inode.c | 6 +- fs/ext4/ioctl.c | 6 +- fs/ext4/namei.c | 16 ++--- fs/ext4/symlink.c | 2 +- fs/ext4/xattr_hurd.c | 2 +- fs/ext4/xattr_security.c | 2 +- fs/ext4/xattr_trusted.c | 2 +- fs/ext4/xattr_user.c | 2 +- fs/f2fs/acl.c | 6 +- fs/f2fs/acl.h | 2 +- fs/f2fs/f2fs.h | 8 +-- fs/f2fs/file.c | 14 ++-- fs/f2fs/namei.c | 24 +++---- fs/f2fs/xattr.c | 4 +- fs/failfs.c | 4 +- fs/fat/fat.h | 4 +- fs/fat/file.c | 6 +- fs/fat/namei_msdos.c | 6 +- fs/fat/namei_vfat.c | 6 +- fs/fhandle.c | 2 +- fs/file_attr.c | 6 +- fs/fuse/acl.c | 4 +- fs/fuse/dir.c | 51 +++++++------- fs/fuse/file.c | 2 +- fs/fuse/fuse_i.h | 12 ++-- fs/fuse/ioctl.c | 2 +- fs/fuse/req.c | 8 ++- fs/fuse/xattr.c | 2 +- fs/gfs2/acl.c | 2 +- fs/gfs2/acl.h | 2 +- fs/gfs2/file.c | 2 +- fs/gfs2/inode.c | 16 ++--- fs/gfs2/inode.h | 4 +- fs/gfs2/xattr.c | 2 +- fs/hfs/attr.c | 2 +- fs/hfs/dir.c | 6 +- fs/hfs/hfs_fs.h | 2 +- fs/hfs/inode.c | 2 +- fs/hfsplus/dir.c | 10 +-- fs/hfsplus/hfsplus_fs.h | 4 +- fs/hfsplus/inode.c | 6 +- fs/hfsplus/xattr.c | 2 +- fs/hfsplus/xattr_security.c | 2 +- fs/hfsplus/xattr_trusted.c | 2 +- fs/hfsplus/xattr_user.c | 2 +- fs/hostfs/hostfs_kern.c | 14 ++-- fs/hpfs/hpfs_fn.h | 2 +- fs/hpfs/inode.c | 2 +- fs/hpfs/namei.c | 10 +-- fs/hugetlbfs/inode.c | 14 ++-- fs/inode.c | 12 ++-- fs/internal.h | 28 ++++---- fs/jffs2/acl.c | 2 +- fs/jffs2/acl.h | 2 +- fs/jffs2/dir.c | 20 +++--- fs/jffs2/fs.c | 2 +- fs/jffs2/os-linux.h | 2 +- fs/jffs2/security.c | 2 +- fs/jffs2/xattr_trusted.c | 2 +- fs/jffs2/xattr_user.c | 2 +- fs/jfs/acl.c | 2 +- fs/jfs/file.c | 2 +- fs/jfs/ioctl.c | 2 +- fs/jfs/jfs_acl.h | 2 +- fs/jfs/jfs_inode.h | 4 +- fs/jfs/namei.c | 10 +-- fs/jfs/xattr.c | 4 +- fs/kernfs/dir.c | 4 +- fs/kernfs/inode.c | 10 +-- fs/kernfs/kernfs-internal.h | 6 +- fs/libfs.c | 8 +-- fs/minix/file.c | 2 +- fs/minix/inode.c | 2 +- fs/minix/minix.h | 2 +- fs/minix/namei.c | 12 ++-- fs/mnt_idmapping.c | 33 +++++---- fs/namei.c | 84 +++++++++++------------ fs/namespace.c | 8 +-- fs/nfs/dir.c | 12 ++-- fs/nfs/inode.c | 4 +- fs/nfs/internal.h | 10 +-- fs/nfs/namespace.c | 4 +- fs/nfs/nfs3_fs.h | 2 +- fs/nfs/nfs3acl.c | 2 +- fs/nfs/nfs4proc.c | 10 +-- fs/nilfs2/inode.c | 4 +- fs/nilfs2/ioctl.c | 2 +- fs/nilfs2/namei.c | 10 +-- fs/nilfs2/nilfs.h | 6 +- fs/ntfs/ea.c | 10 +-- fs/ntfs/ea.h | 6 +- fs/ntfs/file.c | 4 +- fs/ntfs/inode.h | 4 +- fs/ntfs/namei.c | 12 ++-- fs/ntfs3/file.c | 6 +- fs/ntfs3/inode.c | 2 +- fs/ntfs3/namei.c | 10 +-- fs/ntfs3/ntfs_fs.h | 16 ++--- fs/ntfs3/xattr.c | 12 ++-- fs/ocfs2/acl.c | 2 +- fs/ocfs2/acl.h | 2 +- fs/ocfs2/dlmfs/dlmfs.c | 6 +- fs/ocfs2/file.c | 6 +- fs/ocfs2/file.h | 6 +- fs/ocfs2/ioctl.c | 2 +- fs/ocfs2/ioctl.h | 2 +- fs/ocfs2/namei.c | 10 +-- fs/ocfs2/xattr.c | 6 +- fs/omfs/dir.c | 6 +- fs/omfs/file.c | 2 +- fs/open.c | 6 +- fs/orangefs/acl.c | 2 +- fs/orangefs/inode.c | 8 +-- fs/orangefs/namei.c | 8 +-- fs/orangefs/orangefs-kernel.h | 8 +-- fs/orangefs/xattr.c | 2 +- fs/overlayfs/dir.c | 14 ++-- fs/overlayfs/file.c | 2 +- fs/overlayfs/inode.c | 16 ++--- fs/overlayfs/overlayfs.h | 14 ++-- fs/overlayfs/ovl_entry.h | 2 +- fs/overlayfs/util.c | 4 +- fs/overlayfs/xattrs.c | 4 +- fs/pidfs.c | 6 +- fs/posix_acl.c | 26 +++---- fs/proc/base.c | 10 +-- fs/proc/fd.c | 6 +- fs/proc/fd.h | 2 +- fs/proc/generic.c | 4 +- fs/proc/internal.h | 4 +- fs/proc/proc_net.c | 2 +- fs/proc/proc_sysctl.c | 6 +- fs/proc/root.c | 2 +- fs/quota/dquot.c | 2 +- fs/ramfs/file-nommu.c | 4 +- fs/ramfs/inode.c | 10 +-- fs/remap_range.c | 2 +- fs/smb/client/cifsacl.c | 4 +- fs/smb/client/cifsfs.c | 2 +- fs/smb/client/cifsfs.h | 16 ++--- fs/smb/client/cifsproto.h | 4 +- fs/smb/client/dir.c | 6 +- fs/smb/client/inode.c | 8 +-- fs/smb/client/link.c | 2 +- fs/smb/client/xattr.c | 2 +- fs/smb/server/ndr.c | 2 +- fs/smb/server/ndr.h | 2 +- fs/smb/server/oplock.c | 2 +- fs/smb/server/smb2pdu.c | 22 +++--- fs/smb/server/smb_common.c | 2 +- fs/smb/server/smbacl.c | 20 +++--- fs/smb/server/smbacl.h | 8 +-- fs/smb/server/vfs.c | 44 ++++++------ fs/smb/server/vfs.h | 28 ++++---- fs/stat.c | 4 +- fs/tracefs/event_inode.c | 2 +- fs/tracefs/inode.c | 8 +-- fs/ubifs/dir.c | 14 ++-- fs/ubifs/file.c | 4 +- fs/ubifs/ioctl.c | 2 +- fs/ubifs/ubifs.h | 6 +- fs/ubifs/xattr.c | 2 +- fs/udf/file.c | 2 +- fs/udf/namei.c | 12 ++-- fs/udf/symlink.c | 2 +- fs/ufs/inode.c | 2 +- fs/ufs/namei.c | 10 +-- fs/ufs/ufs.h | 2 +- fs/vboxsf/dir.c | 8 +-- fs/vboxsf/utils.c | 4 +- fs/vboxsf/vfsmod.h | 4 +- fs/xattr.c | 30 ++++----- fs/xfs/libxfs/xfs_inode_util.h | 2 +- fs/xfs/xfs_acl.c | 2 +- fs/xfs/xfs_acl.h | 2 +- fs/xfs/xfs_inode.c | 4 +- fs/xfs/xfs_inode.h | 2 +- fs/xfs/xfs_ioctl.c | 2 +- fs/xfs/xfs_ioctl.h | 2 +- fs/xfs/xfs_iops.c | 24 +++---- fs/xfs/xfs_iops.h | 2 +- fs/xfs/xfs_itable.c | 2 +- fs/xfs/xfs_itable.h | 2 +- fs/xfs/xfs_symlink.c | 2 +- fs/xfs/xfs_symlink.h | 2 +- fs/xfs/xfs_xattr.c | 2 +- fs/zonefs/super.c | 2 +- include/linux/capability.h | 8 +-- include/linux/fileattr.h | 2 +- include/linux/fs.h | 108 +++++++++++++++--------------- include/linux/lsm_hook_defs.h | 24 +++---- include/linux/mnt_idmapping.h | 24 +++---- include/linux/mount.h | 4 +- include/linux/namei.h | 16 ++--- include/linux/nfs_fs.h | 6 +- include/linux/posix_acl.h | 24 +++---- include/linux/quotaops.h | 6 +- include/linux/security.h | 54 +++++++-------- include/linux/uidgid.h | 12 ++-- include/linux/xattr.h | 20 +++--- ipc/mqueue.c | 2 +- kernel/bpf/inode.c | 6 +- kernel/capability.c | 4 +- kernel/user_namespace.c | 28 ++++---- mm/secretmem.c | 2 +- mm/shmem.c | 30 ++++----- net/socket.c | 6 +- net/unix/af_unix.c | 2 +- security/apparmor/apparmorfs.c | 2 +- security/apparmor/lsm.c | 4 +- security/commoncap.c | 10 +-- security/integrity/evm/evm_main.c | 26 +++---- security/integrity/ima/ima.h | 10 +-- security/integrity/ima/ima_api.c | 2 +- security/integrity/ima/ima_appraise.c | 12 ++-- security/integrity/ima/ima_main.c | 6 +- security/integrity/ima/ima_policy.c | 4 +- security/security.c | 24 +++---- security/selinux/hooks.c | 14 ++-- security/selinux/selinuxfs.c | 2 +- security/smack/smack_lsm.c | 14 ++-- virt/kvm/guest_memfd.c | 2 +- 296 files changed, 1156 insertions(+), 1135 deletions(-) --- base-commit: cee9395acd8043be0644b25c34bfa86623f2b935 change-id: 20260901-work-idmap-const-bafb8e12a7fa
