diff options
Diffstat (limited to 'include/linux/fs.h')
| -rw-r--r-- | include/linux/fs.h | 140 |
1 files changed, 134 insertions, 6 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 9ad5e3520fae..ec2e35886779 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -221,8 +221,26 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset, struct iattr { unsigned int ia_valid; umode_t ia_mode; - kuid_t ia_uid; - kgid_t ia_gid; + /* + * The two anonymous unions wrap structures with the same member. + * + * Filesystems raising FS_ALLOW_IDMAP need to use ia_vfs{g,u}id which + * are a dedicated type requiring the filesystem to use the dedicated + * helpers. Other filesystem can continue to use ia_{g,u}id until they + * have been ported. + * + * They always contain the same value. In other words FS_ALLOW_IDMAP + * pass down the same value on idmapped mounts as they would on regular + * mounts. + */ + union { + kuid_t ia_uid; + vfsuid_t ia_vfsuid; + }; + union { + kgid_t ia_gid; + vfsgid_t ia_vfsgid; + }; loff_t ia_size; struct timespec64 ia_atime; struct timespec64 ia_mtime; @@ -1600,13 +1618,68 @@ static inline void i_gid_write(struct inode *inode, gid_t gid) * @mnt_userns: user namespace of the mount the inode was found from * @inode: inode to map * + * Note, this will eventually be removed completely in favor of the type-safe + * i_uid_into_vfsuid(). + * * Return: the inode's i_uid mapped down according to @mnt_userns. * If the inode's i_uid has no mapping INVALID_UID is returned. */ static inline kuid_t i_uid_into_mnt(struct user_namespace *mnt_userns, const struct inode *inode) { - return mapped_kuid_fs(mnt_userns, i_user_ns(inode), inode->i_uid); + return AS_KUIDT(make_vfsuid(mnt_userns, i_user_ns(inode), inode->i_uid)); +} + +/** + * i_uid_into_vfsuid - map an inode's i_uid down into a mnt_userns + * @mnt_userns: user namespace of the mount the inode was found from + * @inode: inode to map + * + * Return: whe inode's i_uid mapped down according to @mnt_userns. + * If the inode's i_uid has no mapping INVALID_VFSUID is returned. + */ +static inline vfsuid_t i_uid_into_vfsuid(struct user_namespace *mnt_userns, + const struct inode *inode) +{ + return make_vfsuid(mnt_userns, i_user_ns(inode), inode->i_uid); +} + +/** + * i_uid_needs_update - check whether inode's i_uid needs to be updated + * @mnt_userns: user namespace of the mount the inode was found from + * @attr: the new attributes of @inode + * @inode: the inode to update + * + * Check whether the $inode's i_uid field needs to be updated taking idmapped + * mounts into account if the filesystem supports it. + * + * Return: true if @inode's i_uid field needs to be updated, false if not. + */ +static inline bool i_uid_needs_update(struct user_namespace *mnt_userns, + const struct iattr *attr, + const struct inode *inode) +{ + return ((attr->ia_valid & ATTR_UID) && + !vfsuid_eq(attr->ia_vfsuid, + i_uid_into_vfsuid(mnt_userns, inode))); +} + +/** + * i_uid_update - update @inode's i_uid field + * @mnt_userns: user namespace of the mount the inode was found from + * @attr: the new attributes of @inode + * @inode: the inode to update + * + * Safely update @inode's i_uid field translating the vfsuid of any idmapped + * mount into the filesystem kuid. + */ +static inline void i_uid_update(struct user_namespace *mnt_userns, + const struct iattr *attr, + struct inode *inode) +{ + if (attr->ia_valid & ATTR_UID) + inode->i_uid = from_vfsuid(mnt_userns, i_user_ns(inode), + attr->ia_vfsuid); } /** @@ -1614,13 +1687,68 @@ static inline kuid_t i_uid_into_mnt(struct user_namespace *mnt_userns, * @mnt_userns: user namespace of the mount the inode was found from * @inode: inode to map * + * Note, this will eventually be removed completely in favor of the type-safe + * i_gid_into_vfsgid(). + * * Return: the inode's i_gid mapped down according to @mnt_userns. * If the inode's i_gid has no mapping INVALID_GID is returned. */ static inline kgid_t i_gid_into_mnt(struct user_namespace *mnt_userns, const struct inode *inode) { - return mapped_kgid_fs(mnt_userns, i_user_ns(inode), inode->i_gid); + return AS_KGIDT(make_vfsgid(mnt_userns, i_user_ns(inode), inode->i_gid)); +} + +/** + * i_gid_into_vfsgid - map an inode's i_gid down into a mnt_userns + * @mnt_userns: user namespace of the mount the inode was found from + * @inode: inode to map + * + * Return: the inode's i_gid mapped down according to @mnt_userns. + * If the inode's i_gid has no mapping INVALID_VFSGID is returned. + */ +static inline vfsgid_t i_gid_into_vfsgid(struct user_namespace *mnt_userns, + const struct inode *inode) +{ + return make_vfsgid(mnt_userns, i_user_ns(inode), inode->i_gid); +} + +/** + * i_gid_needs_update - check whether inode's i_gid needs to be updated + * @mnt_userns: user namespace of the mount the inode was found from + * @attr: the new attributes of @inode + * @inode: the inode to update + * + * Check whether the $inode's i_gid field needs to be updated taking idmapped + * mounts into account if the filesystem supports it. + * + * Return: true if @inode's i_gid field needs to be updated, false if not. + */ +static inline bool i_gid_needs_update(struct user_namespace *mnt_userns, + const struct iattr *attr, + const struct inode *inode) +{ + return ((attr->ia_valid & ATTR_GID) && + !vfsgid_eq(attr->ia_vfsgid, + i_gid_into_vfsgid(mnt_userns, inode))); +} + +/** + * i_gid_update - update @inode's i_gid field + * @mnt_userns: user namespace of the mount the inode was found from + * @attr: the new attributes of @inode + * @inode: the inode to update + * + * Safely update @inode's i_gid field translating the vfsgid of any idmapped + * mount into the filesystem kgid. + */ +static inline void i_gid_update(struct user_namespace *mnt_userns, + const struct iattr *attr, + struct inode *inode) +{ + if (attr->ia_valid & ATTR_GID) + inode->i_gid = from_vfsgid(mnt_userns, i_user_ns(inode), + attr->ia_vfsgid); } /** @@ -2195,8 +2323,8 @@ static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags static inline bool HAS_UNMAPPED_ID(struct user_namespace *mnt_userns, struct inode *inode) { - return !uid_valid(i_uid_into_mnt(mnt_userns, inode)) || - !gid_valid(i_gid_into_mnt(mnt_userns, inode)); + return !vfsuid_valid(i_uid_into_vfsuid(mnt_userns, inode)) || + !vfsgid_valid(i_gid_into_vfsgid(mnt_userns, inode)); } static inline int iocb_flags(struct file *file); |