ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 12:43:29 +02:00
Code Issues Packages Projects Releases Wiki Activity

fs: port ->permission() to pass mnt_idmap

Browse Source 
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
This commit is contained in:
Christian Brauner
2023-01-13 12:49:22 +01:00
committed by Christian Brauner (Microsoft)
parent 8782a9aea3
commit 4609e1f18e
84 changed files with 422 additions and 421 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
include/linux/fs.h
View File

@@ -1766,18 +1766,19 @@ static inline void inode_fsgid_set(struct inode *inode,
/**
* fsuidgid_has_mapping() - check whether caller's fsuid/fsgid is mapped
* @sb: the superblock we want a mapping in
* @mnt_userns: user namespace of the relevant mount
* @idmap: idmap of the relevant mount
*
* Check whether the caller's fsuid and fsgid have a valid mapping in the
* s_user_ns of the superblock @sb. If the caller is on an idmapped mount map
* the caller's fsuid and fsgid according to the @mnt_userns first.
* the caller's fsuid and fsgid according to the @idmap first.
*
* Return: true if fsuid and fsgid is mapped, false if not.
*/
static inline bool fsuidgid_has_mapping(struct super_block *sb,
struct user_namespace *mnt_userns)
struct mnt_idmap *idmap)
{
struct user_namespace *fs_userns = sb->s_user_ns;
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
kuid_t kuid;
kgid_t kgid;
@@ -2134,7 +2135,7 @@ struct file_operations {
struct inode_operations {
struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
int (*permission) (struct user_namespace *, struct inode *, int);
int (*permission) (struct mnt_idmap *, struct inode *, int);
struct posix_acl * (*get_inode_acl)(struct inode *, int, bool);
int (*readlink) (struct dentry *, char __user *,int);
@@ -2322,9 +2323,11 @@ static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags
#define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
(inode)->i_rdev == WHITEOUT_DEV)
static inline bool HAS_UNMAPPED_ID(struct user_namespace *mnt_userns,
static inline bool HAS_UNMAPPED_ID(struct mnt_idmap *idmap,
struct inode *inode)
{
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
return !vfsuid_valid(i_uid_into_vfsuid(mnt_userns, inode)) ||
!vfsgid_valid(i_gid_into_vfsgid(mnt_userns, inode));
}
@@ -2902,16 +2905,16 @@ static inline int bmap(struct inode *inode, sector_t *block)
int notify_change(struct mnt_idmap *, struct dentry *,
struct iattr *, struct inode **);
int inode_permission(struct user_namespace *, struct inode *, int);
int generic_permission(struct user_namespace *, struct inode *, int);
int inode_permission(struct mnt_idmap *, struct inode *, int);
int generic_permission(struct mnt_idmap *, struct inode *, int);
static inline int file_permission(struct file *file, int mask)
{
return inode_permission(file_mnt_user_ns(file),
return inode_permission(file_mnt_idmap(file),
file_inode(file), mask);
}
static inline int path_permission(const struct path *path, int mask)
{
return inode_permission(mnt_user_ns(path->mnt),
return inode_permission(mnt_idmap(path->mnt),
d_inode(path->dentry), mask);
}
int __check_sticky(struct user_namespace *mnt_userns, struct inode *dir,
@@ -3365,7 +3368,7 @@ extern int generic_check_addressable(unsigned, u64);
extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry);
int may_setattr(struct user_namespace *mnt_userns, struct inode *inode,
int may_setattr(struct mnt_idmap *idmap, struct inode *inode,
unsigned int ia_valid);
int setattr_prepare(struct mnt_idmap *, struct dentry *, struct iattr *);
extern int inode_newsize_ok(const struct inode *, loff_t offset);