userns: Allow chown and setgid preservation
- Allow chown if CAP_CHOWN is present in the current user namespace and the uid of the inode maps into the current user namespace, and the destination uid or gid maps into the current user namespace. - Allow perserving setgid when changing an inode if CAP_FSETID is present in the current user namespace and the owner of the file has a mapping into the current user namespace. Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
parent
5eaf563e53
commit
7fa294c899
11
fs/attr.c
11
fs/attr.c
|
@ -49,14 +49,15 @@ int inode_change_ok(const struct inode *inode, struct iattr *attr)
|
||||||
/* Make sure a caller can chown. */
|
/* Make sure a caller can chown. */
|
||||||
if ((ia_valid & ATTR_UID) &&
|
if ((ia_valid & ATTR_UID) &&
|
||||||
(!uid_eq(current_fsuid(), inode->i_uid) ||
|
(!uid_eq(current_fsuid(), inode->i_uid) ||
|
||||||
!uid_eq(attr->ia_uid, inode->i_uid)) && !capable(CAP_CHOWN))
|
!uid_eq(attr->ia_uid, inode->i_uid)) &&
|
||||||
|
!inode_capable(inode, CAP_CHOWN))
|
||||||
return -EPERM;
|
return -EPERM;
|
||||||
|
|
||||||
/* Make sure caller can chgrp. */
|
/* Make sure caller can chgrp. */
|
||||||
if ((ia_valid & ATTR_GID) &&
|
if ((ia_valid & ATTR_GID) &&
|
||||||
(!uid_eq(current_fsuid(), inode->i_uid) ||
|
(!uid_eq(current_fsuid(), inode->i_uid) ||
|
||||||
(!in_group_p(attr->ia_gid) && !gid_eq(attr->ia_gid, inode->i_gid))) &&
|
(!in_group_p(attr->ia_gid) && !gid_eq(attr->ia_gid, inode->i_gid))) &&
|
||||||
!capable(CAP_CHOWN))
|
!inode_capable(inode, CAP_CHOWN))
|
||||||
return -EPERM;
|
return -EPERM;
|
||||||
|
|
||||||
/* Make sure a caller can chmod. */
|
/* Make sure a caller can chmod. */
|
||||||
|
@ -65,7 +66,8 @@ int inode_change_ok(const struct inode *inode, struct iattr *attr)
|
||||||
return -EPERM;
|
return -EPERM;
|
||||||
/* Also check the setgid bit! */
|
/* Also check the setgid bit! */
|
||||||
if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
|
if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
|
||||||
inode->i_gid) && !capable(CAP_FSETID))
|
inode->i_gid) &&
|
||||||
|
!inode_capable(inode, CAP_FSETID))
|
||||||
attr->ia_mode &= ~S_ISGID;
|
attr->ia_mode &= ~S_ISGID;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
@ -157,7 +159,8 @@ void setattr_copy(struct inode *inode, const struct iattr *attr)
|
||||||
if (ia_valid & ATTR_MODE) {
|
if (ia_valid & ATTR_MODE) {
|
||||||
umode_t mode = attr->ia_mode;
|
umode_t mode = attr->ia_mode;
|
||||||
|
|
||||||
if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
|
if (!in_group_p(inode->i_gid) &&
|
||||||
|
!inode_capable(inode, CAP_FSETID))
|
||||||
mode &= ~S_ISGID;
|
mode &= ~S_ISGID;
|
||||||
inode->i_mode = mode;
|
inode->i_mode = mode;
|
||||||
}
|
}
|
||||||
|
|
Loading…
Reference in New Issue