diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/evm.h | 6 | ||||
| -rw-r--r-- | include/linux/fs.h | 140 | ||||
| -rw-r--r-- | include/linux/mnt_idmapping.h | 279 | ||||
| -rw-r--r-- | include/linux/quotaops.h | 15 | ||||
| -rw-r--r-- | include/linux/security.h | 8 |
5 files changed, 399 insertions, 49 deletions
diff --git a/include/linux/evm.h b/include/linux/evm.h index 4c374be70247..aa63e0b3c0a2 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -21,7 +21,8 @@ extern enum integrity_status evm_verifyxattr(struct dentry *dentry, void *xattr_value, size_t xattr_value_len, struct integrity_iint_cache *iint); -extern int evm_inode_setattr(struct dentry *dentry, struct iattr *attr); +extern int evm_inode_setattr(struct user_namespace *mnt_userns, + struct dentry *dentry, struct iattr *attr); extern void evm_inode_post_setattr(struct dentry *dentry, int ia_valid); extern int evm_inode_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, const char *name, @@ -68,7 +69,8 @@ static inline enum integrity_status evm_verifyxattr(struct dentry *dentry, } #endif -static inline int evm_inode_setattr(struct dentry *dentry, struct iattr *attr) +static inline int evm_inode_setattr(struct user_namespace *mnt_userns, + struct dentry *dentry, struct iattr *attr) { return 0; } 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); diff --git a/include/linux/mnt_idmapping.h b/include/linux/mnt_idmapping.h index ee5a217de2a8..41dc80f8b67c 100644 --- a/include/linux/mnt_idmapping.h +++ b/include/linux/mnt_idmapping.h @@ -13,6 +13,129 @@ struct user_namespace; */ extern struct user_namespace init_user_ns; +typedef struct { + uid_t val; +} vfsuid_t; + +typedef struct { + gid_t val; +} vfsgid_t; + +static_assert(sizeof(vfsuid_t) == sizeof(kuid_t)); +static_assert(sizeof(vfsgid_t) == sizeof(kgid_t)); +static_assert(offsetof(vfsuid_t, val) == offsetof(kuid_t, val)); +static_assert(offsetof(vfsgid_t, val) == offsetof(kgid_t, val)); + +#ifdef CONFIG_MULTIUSER +static inline uid_t __vfsuid_val(vfsuid_t uid) +{ + return uid.val; +} + +static inline gid_t __vfsgid_val(vfsgid_t gid) +{ + return gid.val; +} +#else +static inline uid_t __vfsuid_val(vfsuid_t uid) +{ + return 0; +} + +static inline gid_t __vfsgid_val(vfsgid_t gid) +{ + return 0; +} +#endif + +static inline bool vfsuid_valid(vfsuid_t uid) +{ + return __vfsuid_val(uid) != (uid_t)-1; +} + +static inline bool vfsgid_valid(vfsgid_t gid) +{ + return __vfsgid_val(gid) != (gid_t)-1; +} + +static inline bool vfsuid_eq(vfsuid_t left, vfsuid_t right) +{ + return vfsuid_valid(left) && __vfsuid_val(left) == __vfsuid_val(right); +} + +static inline bool vfsgid_eq(vfsgid_t left, vfsgid_t right) +{ + return vfsgid_valid(left) && __vfsgid_val(left) == __vfsgid_val(right); +} + +/** + * vfsuid_eq_kuid - check whether kuid and vfsuid have the same value + * @vfsuid: the vfsuid to compare + * @kuid: the kuid to compare + * + * Check whether @vfsuid and @kuid have the same values. + * + * Return: true if @vfsuid and @kuid have the same value, false if not. + * Comparison between two invalid uids returns false. + */ +static inline bool vfsuid_eq_kuid(vfsuid_t vfsuid, kuid_t kuid) +{ + return vfsuid_valid(vfsuid) && __vfsuid_val(vfsuid) == __kuid_val(kuid); +} + +/** + * vfsgid_eq_kgid - check whether kgid and vfsgid have the same value + * @vfsgid: the vfsgid to compare + * @kgid: the kgid to compare + * + * Check whether @vfsgid and @kgid have the same values. + * + * Return: true if @vfsgid and @kgid have the same value, false if not. + * Comparison between two invalid gids returns false. + */ +static inline bool vfsgid_eq_kgid(vfsgid_t vfsgid, kgid_t kgid) +{ + return vfsgid_valid(vfsgid) && __vfsgid_val(vfsgid) == __kgid_val(kgid); +} + +/* + * vfs{g,u}ids are created from k{g,u}ids. + * We don't allow them to be created from regular {u,g}id. + */ +#define VFSUIDT_INIT(val) (vfsuid_t){ __kuid_val(val) } +#define VFSGIDT_INIT(val) (vfsgid_t){ __kgid_val(val) } + +#define INVALID_VFSUID VFSUIDT_INIT(INVALID_UID) +#define INVALID_VFSGID VFSGIDT_INIT(INVALID_GID) + +/* + * Allow a vfs{g,u}id to be used as a k{g,u}id where we want to compare + * whether the mapped value is identical to value of a k{g,u}id. + */ +#define AS_KUIDT(val) (kuid_t){ __vfsuid_val(val) } +#define AS_KGIDT(val) (kgid_t){ __vfsgid_val(val) } + +#ifdef CONFIG_MULTIUSER +/** + * vfsgid_in_group_p() - check whether a vfsuid matches the caller's groups + * @vfsgid: the mnt gid to match + * + * This function can be used to determine whether @vfsuid matches any of the + * caller's groups. + * + * Return: 1 if vfsuid matches caller's groups, 0 if not. + */ +static inline int vfsgid_in_group_p(vfsgid_t vfsgid) +{ + return in_group_p(AS_KGIDT(vfsgid)); +} +#else +static inline int vfsgid_in_group_p(vfsgid_t vfsgid) +{ + return 1; +} +#endif + /** * initial_idmapping - check whether this is the initial mapping * @ns: idmapping to check @@ -48,7 +171,7 @@ static inline bool no_idmapping(const struct user_namespace *mnt_userns, } /** - * mapped_kuid_fs - map a filesystem kuid into a mnt_userns + * make_vfsuid - map a filesystem kuid into a mnt_userns * @mnt_userns: the mount's idmapping * @fs_userns: the filesystem's idmapping * @kuid : kuid to be mapped @@ -67,25 +190,33 @@ static inline bool no_idmapping(const struct user_namespace *mnt_userns, * If @kuid has no mapping in either @mnt_userns or @fs_userns INVALID_UID is * returned. */ -static inline kuid_t mapped_kuid_fs(struct user_namespace *mnt_userns, - struct user_namespace *fs_userns, - kuid_t kuid) + +static inline vfsuid_t make_vfsuid(struct user_namespace *mnt_userns, + struct user_namespace *fs_userns, + kuid_t kuid) { uid_t uid; if (no_idmapping(mnt_userns, fs_userns)) - return kuid; + return VFSUIDT_INIT(kuid); if (initial_idmapping(fs_userns)) uid = __kuid_val(kuid); else uid = from_kuid(fs_userns, kuid); if (uid == (uid_t)-1) - return INVALID_UID; - return make_kuid(mnt_userns, uid); + return INVALID_VFSUID; + return VFSUIDT_INIT(make_kuid(mnt_userns, uid)); +} + +static inline kuid_t mapped_kuid_fs(struct user_namespace *mnt_userns, + struct user_namespace *fs_userns, + kuid_t kuid) +{ + return AS_KUIDT(make_vfsuid(mnt_userns, fs_userns, kuid)); } /** - * mapped_kgid_fs - map a filesystem kgid into a mnt_userns + * make_vfsgid - map a filesystem kgid into a mnt_userns * @mnt_userns: the mount's idmapping * @fs_userns: the filesystem's idmapping * @kgid : kgid to be mapped @@ -104,21 +235,56 @@ static inline kuid_t mapped_kuid_fs(struct user_namespace *mnt_userns, * If @kgid has no mapping in either @mnt_userns or @fs_userns INVALID_GID is * returned. */ -static inline kgid_t mapped_kgid_fs(struct user_namespace *mnt_userns, - struct user_namespace *fs_userns, - kgid_t kgid) + +static inline vfsgid_t make_vfsgid(struct user_namespace *mnt_userns, + struct user_namespace *fs_userns, + kgid_t kgid) { gid_t gid; if (no_idmapping(mnt_userns, fs_userns)) - return kgid; + return VFSGIDT_INIT(kgid); if (initial_idmapping(fs_userns)) gid = __kgid_val(kgid); else gid = from_kgid(fs_userns, kgid); if (gid == (gid_t)-1) - return INVALID_GID; - return make_kgid(mnt_userns, gid); + return INVALID_VFSGID; + return VFSGIDT_INIT(make_kgid(mnt_userns, gid)); +} + +static inline kgid_t mapped_kgid_fs(struct user_namespace *mnt_userns, + struct user_namespace *fs_userns, + kgid_t kgid) +{ + return AS_KGIDT(make_vfsgid(mnt_userns, fs_userns, kgid)); +} + +/** + * from_vfsuid - map a vfsuid into the filesystem idmapping + * @mnt_userns: the mount's idmapping + * @fs_userns: the filesystem's idmapping + * @vfsuid : vfsuid to be mapped + * + * Map @vfsuid into the filesystem idmapping. This function has to be used in + * order to e.g. write @vfsuid to inode->i_uid. + * + * Return: @vfsuid mapped into the filesystem idmapping + */ +static inline kuid_t from_vfsuid(struct user_namespace *mnt_userns, + struct user_namespace *fs_userns, + vfsuid_t vfsuid) +{ + uid_t uid; + + if (no_idmapping(mnt_userns, fs_userns)) + return AS_KUIDT(vfsuid); + uid = from_kuid(mnt_userns, AS_KUIDT(vfsuid)); + if (uid == (uid_t)-1) + return INVALID_UID; + if (initial_idmapping(fs_userns)) + return KUIDT_INIT(uid); + return make_kuid(fs_userns, uid); } /** @@ -145,16 +311,53 @@ static inline kuid_t mapped_kuid_user(struct user_namespace *mnt_userns, struct user_namespace *fs_userns, kuid_t kuid) { - uid_t uid; + return from_vfsuid(mnt_userns, fs_userns, VFSUIDT_INIT(kuid)); +} + +/** + * vfsuid_has_fsmapping - check whether a vfsuid maps into the filesystem + * @mnt_userns: the mount's idmapping + * @fs_userns: the filesystem's idmapping + * @vfsuid: vfsuid to be mapped + * + * Check whether @vfsuid has a mapping in the filesystem idmapping. Use this + * function to check whether the filesystem idmapping has a mapping for + * @vfsuid. + * + * Return: true if @vfsuid has a mapping in the filesystem, false if not. + */ +static inline bool vfsuid_has_fsmapping(struct user_namespace *mnt_userns, + struct user_namespace *fs_userns, + vfsuid_t vfsuid) +{ + return uid_valid(from_vfsuid(mnt_userns, fs_userns, vfsuid)); +} + +/** + * from_vfsgid - map a vfsgid into the filesystem idmapping + * @mnt_userns: the mount's idmapping + * @fs_userns: the filesystem's idmapping + * @vfsgid : vfsgid to be mapped + * + * Map @vfsgid into the filesystem idmapping. This function has to be used in + * order to e.g. write @vfsgid to inode->i_gid. + * + * Return: @vfsgid mapped into the filesystem idmapping + */ +static inline kgid_t from_vfsgid(struct user_namespace *mnt_userns, + struct user_namespace *fs_userns, + vfsgid_t vfsgid) +{ + gid_t gid; if (no_idmapping(mnt_userns, fs_userns)) - return kuid; - uid = from_kuid(mnt_userns, kuid); - if (uid == (uid_t)-1) - return INVALID_UID; + return AS_KGIDT(vfsgid); + gid = from_kgid(mnt_userns, AS_KGIDT(vfsgid)); + if (gid == (gid_t)-1) + return INVALID_GID; if (initial_idmapping(fs_userns)) - return KUIDT_INIT(uid); - return make_kuid(fs_userns, uid); + return KGIDT_INIT(gid); + return make_kgid(fs_userns, gid); } /** @@ -181,16 +384,26 @@ static inline kgid_t mapped_kgid_user(struct user_namespace *mnt_userns, struct user_namespace *fs_userns, kgid_t kgid) { - gid_t gid; + return from_vfsgid(mnt_userns, fs_userns, VFSGIDT_INIT(kgid)); +} - if (no_idmapping(mnt_userns, fs_userns)) - return kgid; - gid = from_kgid(mnt_userns, kgid); - if (gid == (gid_t)-1) - return INVALID_GID; - if (initial_idmapping(fs_userns)) - return KGIDT_INIT(gid); - return make_kgid(fs_userns, gid); +/** + * vfsgid_has_fsmapping - check whether a vfsgid maps into the filesystem + * @mnt_userns: the mount's idmapping + * @fs_userns: the filesystem's idmapping + * @vfsgid: vfsgid to be mapped + * + * Check whether @vfsgid has a mapping in the filesystem idmapping. Use this + * function to check whether the filesystem idmapping has a mapping for + * @vfsgid. + * + * Return: true if @vfsgid has a mapping in the filesystem, false if not. + */ +static inline bool vfsgid_has_fsmapping(struct user_namespace *mnt_userns, + struct user_namespace *fs_userns, + vfsgid_t vfsgid) +{ + return gid_valid(from_vfsgid(mnt_userns, fs_userns, vfsgid)); } /** @@ -209,7 +422,8 @@ static inline kgid_t mapped_kgid_user(struct user_namespace *mnt_userns, static inline kuid_t mapped_fsuid(struct user_namespace *mnt_userns, struct user_namespace *fs_userns) { - return mapped_kuid_user(mnt_userns, fs_userns, current_fsuid()); + return from_vfsuid(mnt_userns, fs_userns, + VFSUIDT_INIT(current_fsuid())); } /** @@ -228,7 +442,8 @@ static inline kuid_t mapped_fsuid(struct user_namespace *mnt_userns, static inline kgid_t mapped_fsgid(struct user_namespace *mnt_userns, struct user_namespace *fs_userns) { - return mapped_kgid_user(mnt_userns, fs_userns, current_fsgid()); + return from_vfsgid(mnt_userns, fs_userns, + VFSGIDT_INIT(current_fsgid())); } #endif /* _LINUX_MNT_IDMAPPING_H */ diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h index a0f6668924d3..0d8625d71733 100644 --- a/include/linux/quotaops.h +++ b/include/linux/quotaops.h @@ -20,11 +20,12 @@ static inline struct quota_info *sb_dqopt(struct super_block *sb) } /* i_mutex must being held */ -static inline bool is_quota_modification(struct inode *inode, struct iattr *ia) +static inline bool is_quota_modification(struct user_namespace *mnt_userns, + struct inode *inode, struct iattr *ia) { - return (ia->ia_valid & ATTR_SIZE) || - (ia->ia_valid & ATTR_UID && !uid_eq(ia->ia_uid, inode->i_uid)) || - (ia->ia_valid & ATTR_GID && !gid_eq(ia->ia_gid, inode->i_gid)); + return ((ia->ia_valid & ATTR_SIZE) || + i_uid_needs_update(mnt_userns, ia, inode) || + i_gid_needs_update(mnt_userns, ia, inode)); } #if defined(CONFIG_QUOTA) @@ -115,7 +116,8 @@ int dquot_set_dqblk(struct super_block *sb, struct kqid id, struct qc_dqblk *di); int __dquot_transfer(struct inode *inode, struct dquot **transfer_to); -int dquot_transfer(struct inode *inode, struct iattr *iattr); +int dquot_transfer(struct user_namespace *mnt_userns, struct inode *inode, + struct iattr *iattr); static inline struct mem_dqinfo *sb_dqinfo(struct super_block *sb, int type) { @@ -234,7 +236,8 @@ static inline void dquot_free_inode(struct inode *inode) { } -static inline int dquot_transfer(struct inode *inode, struct iattr *iattr) +static inline int dquot_transfer(struct user_namespace *mnt_userns, + struct inode *inode, struct iattr *iattr) { return 0; } diff --git a/include/linux/security.h b/include/linux/security.h index 7fc4e9f49f54..4d0baf30266e 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -353,7 +353,8 @@ int security_inode_readlink(struct dentry *dentry); int security_inode_follow_link(struct dentry *dentry, struct inode *inode, bool rcu); int security_inode_permission(struct inode *inode, int mask); -int security_inode_setattr(struct dentry *dentry, struct iattr *attr); +int security_inode_setattr(struct user_namespace *mnt_userns, + struct dentry *dentry, struct iattr *attr); int security_inode_getattr(const struct path *path); int security_inode_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, const char *name, @@ -848,8 +849,9 @@ static inline int security_inode_permission(struct inode *inode, int mask) return 0; } -static inline int security_inode_setattr(struct dentry *dentry, - struct iattr *attr) +static inline int security_inode_setattr(struct user_namespace *mnt_userns, + struct dentry *dentry, + struct iattr *attr) { return 0; } |