From: Christian Brauner christian.brauner@ubuntu.com
commit 4472071331549e911a5abad41aea6e3be855a1a4 upstream.
In a few places the vfs needs to interact with bare k{g,u}ids directly instead of struct inode. These are just a few. In previous patches we introduced low-level mapping helpers that are able to support filesystems mounted an idmapping. This patch simply converts the places to use these new helpers.
Link: https://lore.kernel.org/r/20211123114227.3124056-7-brauner@kernel.org (v1) Link: https://lore.kernel.org/r/20211130121032.3753852-7-brauner@kernel.org (v2) Link: https://lore.kernel.org/r/20211203111707.3901969-7-brauner@kernel.org Cc: Seth Forshee sforshee@digitalocean.com Cc: Amir Goldstein amir73il@gmail.com Cc: Christoph Hellwig hch@lst.de Cc: Al Viro viro@zeniv.linux.org.uk CC: linux-fsdevel@vger.kernel.org Reviewed-by: Seth Forshee sforshee@digitalocean.com Signed-off-by: Christian Brauner christian.brauner@ubuntu.com Signed-off-by: Christian Brauner (Microsoft) brauner@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ksmbd/smbacl.c | 18 ++---------------- fs/ksmbd/smbacl.h | 4 ++-- fs/open.c | 4 ++-- fs/posix_acl.c | 16 ++++++++++------ security/commoncap.c | 13 ++++++++----- 5 files changed, 24 insertions(+), 31 deletions(-)
--- a/fs/ksmbd/smbacl.c +++ b/fs/ksmbd/smbacl.c @@ -275,14 +275,7 @@ static int sid_to_id(struct user_namespa uid_t id;
id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]); - /* - * Translate raw sid into kuid in the server's user - * namespace. - */ - uid = make_kuid(&init_user_ns, id); - - /* If this is an idmapped mount, apply the idmapping. */ - uid = kuid_from_mnt(user_ns, uid); + uid = mapped_kuid_user(user_ns, &init_user_ns, KUIDT_INIT(id)); if (uid_valid(uid)) { fattr->cf_uid = uid; rc = 0; @@ -292,14 +285,7 @@ static int sid_to_id(struct user_namespa gid_t id;
id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]); - /* - * Translate raw sid into kgid in the server's user - * namespace. - */ - gid = make_kgid(&init_user_ns, id); - - /* If this is an idmapped mount, apply the idmapping. */ - gid = kgid_from_mnt(user_ns, gid); + gid = mapped_kgid_user(user_ns, &init_user_ns, KGIDT_INIT(id)); if (gid_valid(gid)) { fattr->cf_gid = gid; rc = 0; --- a/fs/ksmbd/smbacl.h +++ b/fs/ksmbd/smbacl.h @@ -217,7 +217,7 @@ static inline uid_t posix_acl_uid_transl kuid_t kuid;
/* If this is an idmapped mount, apply the idmapping. */ - kuid = kuid_into_mnt(mnt_userns, pace->e_uid); + kuid = mapped_kuid_fs(mnt_userns, &init_user_ns, pace->e_uid);
/* Translate the kuid into a userspace id ksmbd would see. */ return from_kuid(&init_user_ns, kuid); @@ -229,7 +229,7 @@ static inline gid_t posix_acl_gid_transl kgid_t kgid;
/* If this is an idmapped mount, apply the idmapping. */ - kgid = kgid_into_mnt(mnt_userns, pace->e_gid); + kgid = mapped_kgid_fs(mnt_userns, &init_user_ns, pace->e_gid);
/* Translate the kgid into a userspace id ksmbd would see. */ return from_kgid(&init_user_ns, kgid); --- a/fs/open.c +++ b/fs/open.c @@ -653,8 +653,8 @@ int chown_common(const struct path *path gid = make_kgid(current_user_ns(), group);
mnt_userns = mnt_user_ns(path->mnt); - uid = kuid_from_mnt(mnt_userns, uid); - gid = kgid_from_mnt(mnt_userns, gid); + uid = mapped_kuid_user(mnt_userns, &init_user_ns, uid); + gid = mapped_kgid_user(mnt_userns, &init_user_ns, gid);
retry_deleg: newattrs.ia_valid = ATTR_CTIME; --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -376,7 +376,9 @@ posix_acl_permission(struct user_namespa goto check_perm; break; case ACL_USER: - uid = kuid_into_mnt(mnt_userns, pa->e_uid); + uid = mapped_kuid_fs(mnt_userns, + &init_user_ns, + pa->e_uid); if (uid_eq(uid, current_fsuid())) goto mask; break; @@ -389,7 +391,9 @@ posix_acl_permission(struct user_namespa } break; case ACL_GROUP: - gid = kgid_into_mnt(mnt_userns, pa->e_gid); + gid = mapped_kgid_fs(mnt_userns, + &init_user_ns, + pa->e_gid); if (in_group_p(gid)) { found = 1; if ((pa->e_perm & want) == want) @@ -736,17 +740,17 @@ static void posix_acl_fix_xattr_userns( case ACL_USER: uid = make_kuid(from, le32_to_cpu(entry->e_id)); if (from_user) - uid = kuid_from_mnt(mnt_userns, uid); + uid = mapped_kuid_user(mnt_userns, &init_user_ns, uid); else - uid = kuid_into_mnt(mnt_userns, uid); + uid = mapped_kuid_fs(mnt_userns, &init_user_ns, uid); entry->e_id = cpu_to_le32(from_kuid(to, uid)); break; case ACL_GROUP: gid = make_kgid(from, le32_to_cpu(entry->e_id)); if (from_user) - gid = kgid_from_mnt(mnt_userns, gid); + gid = mapped_kgid_user(mnt_userns, &init_user_ns, gid); else - gid = kgid_into_mnt(mnt_userns, gid); + gid = mapped_kgid_fs(mnt_userns, &init_user_ns, gid); entry->e_id = cpu_to_le32(from_kgid(to, gid)); break; default: --- a/security/commoncap.c +++ b/security/commoncap.c @@ -419,7 +419,7 @@ int cap_inode_getsecurity(struct user_na kroot = make_kuid(fs_ns, root);
/* If this is an idmapped mount shift the kuid. */ - kroot = kuid_into_mnt(mnt_userns, kroot); + kroot = mapped_kuid_fs(mnt_userns, &init_user_ns, kroot);
/* If the root kuid maps to a valid uid in current ns, then return * this as a nscap. */ @@ -489,6 +489,7 @@ out_free: * @size: size of @ivalue * @task_ns: user namespace of the caller * @mnt_userns: user namespace of the mount the inode was found from + * @fs_userns: user namespace of the filesystem * * If the inode has been found through an idmapped mount the user namespace of * the vfsmount must be passed through @mnt_userns. This function will then @@ -498,7 +499,8 @@ out_free: */ static kuid_t rootid_from_xattr(const void *value, size_t size, struct user_namespace *task_ns, - struct user_namespace *mnt_userns) + struct user_namespace *mnt_userns, + struct user_namespace *fs_userns) { const struct vfs_ns_cap_data *nscap = value; kuid_t rootkid; @@ -508,7 +510,7 @@ static kuid_t rootid_from_xattr(const vo rootid = le32_to_cpu(nscap->rootid);
rootkid = make_kuid(task_ns, rootid); - return kuid_from_mnt(mnt_userns, rootkid); + return mapped_kuid_user(mnt_userns, fs_userns, rootkid); }
static bool validheader(size_t size, const struct vfs_cap_data *cap) @@ -559,7 +561,8 @@ int cap_convert_nscap(struct user_namesp /* user is privileged, just write the v2 */ return size;
- rootid = rootid_from_xattr(*ivalue, size, task_ns, mnt_userns); + rootid = rootid_from_xattr(*ivalue, size, task_ns, mnt_userns, + &init_user_ns); if (!uid_valid(rootid)) return -EINVAL;
@@ -700,7 +703,7 @@ int get_vfs_caps_from_disk(struct user_n /* Limit the caps to the mounter of the filesystem * or the more limited uid specified in the xattr. */ - rootkuid = kuid_into_mnt(mnt_userns, rootkuid); + rootkuid = mapped_kuid_fs(mnt_userns, &init_user_ns, rootkuid); if (!rootid_owns_currentns(rootkuid)) return -ENODATA;