Merge tag 'fs.idmapped.v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping

Pull vfs idmapping updates from Christian Brauner:

 - Last cycle we introduced the dedicated struct mnt_idmap type for
   mount idmapping and the required infrastucture in 256c8aed2b42 ("fs:
   introduce dedicated idmap type for mounts"). As promised in last
   cycle's pull request message this converts everything to rely on
   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 relevant on the mount level. Especially for
   non-vfs developers without detailed knowledge in this area this was a
   potential source for bugs.

   This finishes the conversion. Instead of passing the plain namespace
   around this updates all places that currently take a pointer to a
   mnt_userns with a pointer to struct mnt_idmap.

   Now that the conversion is done all helpers down to the really
   low-level helpers only accept a struct mnt_idmap argument instead of
   two namespace arguments.

   Conflating mount and other idmappings will now cause the compiler to
   complain loudly thus eliminating the possibility of any bugs. This
   makes it impossible for filesystem developers to mix up mount and
   filesystem idmappings as they are two distinct types and require
   distinct helpers that cannot be used interchangeably.

   Everything associated with struct mnt_idmap is moved into a single
   separate file. With that change no code can poke around in struct
   mnt_idmap. It can only be interacted with through dedicated helpers.
   That means all filesystems are and all of the vfs is completely
   oblivious to the actual implementation of idmappings.

   We are now also able to extend struct mnt_idmap as we see fit. For
   example, we can decouple it completely from namespaces for users that
   don't require or don't want to use them at all. We can also extend
   the concept of idmappings so we can cover filesystem specific
   requirements.

   In combination with the vfs{g,u}id_t work we finished in v6.2 this
   makes this feature substantially more robust and thus difficult to
   implement wrong by a given filesystem and also protects the vfs.

 - Enable idmapped mounts for tmpfs and fulfill a longstanding request.

   A long-standing request from users had been to make it possible to
   create idmapped mounts for tmpfs. For example, to share the host's
   tmpfs mount between multiple sandboxes. This is a prerequisite for
   some advanced Kubernetes cases. Systemd also has a range of use-cases
   to increase service isolation. And there are more users of this.

   However, with all of the other work going on this was way down on the
   priority list but luckily someone other than ourselves picked this
   up.

   As usual the patch is tiny as all the infrastructure work had been
   done multiple kernel releases ago. In addition to all the tests that
   we already have I requested that Rodrigo add a dedicated tmpfs
   testsuite for idmapped mounts to xfstests. It is to be included into
   xfstests during the v6.3 development cycle. This should add a slew of
   additional tests.

* tag 'fs.idmapped.v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: (26 commits)
  shmem: support idmapped mounts for tmpfs
  fs: move mnt_idmap
  fs: port vfs{g,u}id helpers to mnt_idmap
  fs: port fs{g,u}id helpers to mnt_idmap
  fs: port i_{g,u}id_into_vfs{g,u}id() to mnt_idmap
  fs: port i_{g,u}id_{needs_}update() to mnt_idmap
  quota: port to mnt_idmap
  fs: port privilege checking helpers to mnt_idmap
  fs: port inode_owner_or_capable() to mnt_idmap
  fs: port inode_init_owner() to mnt_idmap
  fs: port acl to mnt_idmap
  fs: port xattr to mnt_idmap
  fs: port ->permission() to pass mnt_idmap
  fs: port ->fileattr_set() to pass mnt_idmap
  fs: port ->set_acl() to pass mnt_idmap
  fs: port ->get_acl() to pass mnt_idmap
  fs: port ->tmpfile() to pass mnt_idmap
  fs: port ->rename() to pass mnt_idmap
  fs: port ->mknod() to pass mnt_idmap
  fs: port ->mkdir() to pass mnt_idmap
  ...

1 files changed, 36 insertions, 36 deletions

diff --git a/fs/ksmbd/smbacl.c b/fs/ksmbd/smbacl.c
index ab5c68cc0e13..6d6cfb6957a9 100644
--- a/fs/ksmbd/smbacl.c
+++ b/fs/ksmbd/smbacl.c
@@ -254,7 +254,7 @@ void id_to_sid(unsigned int cid, uint sidtype, struct smb_sid *ssid)
 	ssid->num_subauth++;
 }
 
-static int sid_to_id(struct user_namespace *user_ns,
+static int sid_to_id(struct mnt_idmap *idmap,
 		     struct smb_sid *psid, uint sidtype,
 		     struct smb_fattr *fattr)
 {
@@ -276,7 +276,7 @@ static int sid_to_id(struct user_namespace *user_ns,
 
 		id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
 		uid = KUIDT_INIT(id);
-		uid = from_vfsuid(user_ns, &init_user_ns, VFSUIDT_INIT(uid));
+		uid = from_vfsuid(idmap, &init_user_ns, VFSUIDT_INIT(uid));
 		if (uid_valid(uid)) {
 			fattr->cf_uid = uid;
 			rc = 0;
@@ -287,7 +287,7 @@ static int sid_to_id(struct user_namespace *user_ns,
 
 		id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
 		gid = KGIDT_INIT(id);
-		gid = from_vfsgid(user_ns, &init_user_ns, VFSGIDT_INIT(gid));
+		gid = from_vfsgid(idmap, &init_user_ns, VFSGIDT_INIT(gid));
 		if (gid_valid(gid)) {
 			fattr->cf_gid = gid;
 			rc = 0;
@@ -362,7 +362,7 @@ void free_acl_state(struct posix_acl_state *state)
 	kfree(state->groups);
 }
 
-static void parse_dacl(struct user_namespace *user_ns,
+static void parse_dacl(struct mnt_idmap *idmap,
 		       struct smb_acl *pdacl, char *end_of_acl,
 		       struct smb_sid *pownersid, struct smb_sid *pgrpsid,
 		       struct smb_fattr *fattr)
@@ -489,7 +489,7 @@ static void parse_dacl(struct user_namespace *user_ns,
 			acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
 							ppace[i]->type);
 			temp_fattr.cf_uid = INVALID_UID;
-			ret = sid_to_id(user_ns, &ppace[i]->sid, SIDOWNER, &temp_fattr);
+			ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr);
 			if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
 				pr_err("%s: Error %d mapping Owner SID to uid\n",
 				       __func__, ret);
@@ -575,7 +575,7 @@ static void parse_dacl(struct user_namespace *user_ns,
 	free_acl_state(&default_acl_state);
 }
 
-static void set_posix_acl_entries_dacl(struct user_namespace *user_ns,
+static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap,
 				       struct smb_ace *pndace,
 				       struct smb_fattr *fattr, u32 *num_aces,
 				       u16 *size, u32 nt_aces_num)
@@ -600,14 +600,14 @@ static void set_posix_acl_entries_dacl(struct user_namespace *user_ns,
 			uid_t uid;
 			unsigned int sid_type = SIDOWNER;
 
-			uid = posix_acl_uid_translate(user_ns, pace);
+			uid = posix_acl_uid_translate(idmap, pace);
 			if (!uid)
 				sid_type = SIDUNIX_USER;
 			id_to_sid(uid, sid_type, sid);
 		} else if (pace->e_tag == ACL_GROUP) {
 			gid_t gid;
 
-			gid = posix_acl_gid_translate(user_ns, pace);
+			gid = posix_acl_gid_translate(idmap, pace);
 			id_to_sid(gid, SIDUNIX_GROUP, sid);
 		} else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
 			smb_copy_sid(sid, &sid_everyone);
@@ -666,12 +666,12 @@ posix_default_acl:
 		if (pace->e_tag == ACL_USER) {
 			uid_t uid;
 
-			uid = posix_acl_uid_translate(user_ns, pace);
+			uid = posix_acl_uid_translate(idmap, pace);
 			id_to_sid(uid, SIDCREATOR_OWNER, sid);
 		} else if (pace->e_tag == ACL_GROUP) {
 			gid_t gid;
 
-			gid = posix_acl_gid_translate(user_ns, pace);
+			gid = posix_acl_gid_translate(idmap, pace);
 			id_to_sid(gid, SIDCREATOR_GROUP, sid);
 		} else {
 			kfree(sid);
@@ -689,7 +689,7 @@ posix_default_acl:
 	}
 }
 
-static void set_ntacl_dacl(struct user_namespace *user_ns,
+static void set_ntacl_dacl(struct mnt_idmap *idmap,
 			   struct smb_acl *pndacl,
 			   struct smb_acl *nt_dacl,
 			   unsigned int aces_size,
@@ -723,13 +723,13 @@ static void set_ntacl_dacl(struct user_namespace *user_ns,
 		}
 	}
 
-	set_posix_acl_entries_dacl(user_ns, pndace, fattr,
+	set_posix_acl_entries_dacl(idmap, pndace, fattr,
 				   &num_aces, &size, nt_num_aces);
 	pndacl->num_aces = cpu_to_le32(num_aces);
 	pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
 }
 
-static void set_mode_dacl(struct user_namespace *user_ns,
+static void set_mode_dacl(struct mnt_idmap *idmap,
 			  struct smb_acl *pndacl, struct smb_fattr *fattr)
 {
 	struct smb_ace *pace, *pndace;
@@ -741,7 +741,7 @@ static void set_mode_dacl(struct user_namespace *user_ns,
 	pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
 
 	if (fattr->cf_acls) {
-		set_posix_acl_entries_dacl(user_ns, pndace, fattr,
+		set_posix_acl_entries_dacl(idmap, pndace, fattr,
 					   &num_aces, &size, num_aces);
 		goto out;
 	}
@@ -808,7 +808,7 @@ static int parse_sid(struct smb_sid *psid, char *end_of_acl)
 }
 
 /* Convert CIFS ACL to POSIX form */
-int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
+int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd,
 		   int acl_len, struct smb_fattr *fattr)
 {
 	int rc = 0;
@@ -851,7 +851,7 @@ int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
 			return rc;
 		}
 
-		rc = sid_to_id(user_ns, owner_sid_ptr, SIDOWNER, fattr);
+		rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr);
 		if (rc) {
 			pr_err("%s: Error %d mapping Owner SID to uid\n",
 			       __func__, rc);
@@ -866,7 +866,7 @@ int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
 			       __func__, rc);
 			return rc;
 		}
-		rc = sid_to_id(user_ns, group_sid_ptr, SIDUNIX_GROUP, fattr);
+		rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr);
 		if (rc) {
 			pr_err("%s: Error %d mapping Group SID to gid\n",
 			       __func__, rc);
@@ -881,7 +881,7 @@ int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
 		pntsd->type |= cpu_to_le16(DACL_PROTECTED);
 
 	if (dacloffset) {
-		parse_dacl(user_ns, dacl_ptr, end_of_acl,
+		parse_dacl(idmap, dacl_ptr, end_of_acl,
 			   owner_sid_ptr, group_sid_ptr, fattr);
 	}
 
@@ -889,7 +889,7 @@ int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
 }
 
 /* Convert permission bits from mode to equivalent CIFS ACL */
-int build_sec_desc(struct user_namespace *user_ns,
+int build_sec_desc(struct mnt_idmap *idmap,
 		   struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
 		   int ppntsd_size, int addition_info, __u32 *secdesclen,
 		   struct smb_fattr *fattr)
@@ -950,7 +950,7 @@ int build_sec_desc(struct user_namespace *user_ns,
 		dacl_ptr->num_aces = 0;
 
 		if (!ppntsd) {
-			set_mode_dacl(user_ns, dacl_ptr, fattr);
+			set_mode_dacl(idmap, dacl_ptr, fattr);
 		} else {
 			struct smb_acl *ppdacl_ptr;
 			unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
@@ -966,7 +966,7 @@ int build_sec_desc(struct user_namespace *user_ns,
 			    ppdacl_size < sizeof(struct smb_acl))
 				goto out;
 
-			set_ntacl_dacl(user_ns, dacl_ptr, ppdacl_ptr,
+			set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr,
 				       ntacl_size - sizeof(struct smb_acl),
 				       nowner_sid_ptr, ngroup_sid_ptr,
 				       fattr);
@@ -1002,13 +1002,13 @@ int smb_inherit_dacl(struct ksmbd_conn *conn,
 	struct smb_ntsd *parent_pntsd = NULL;
 	struct smb_sid owner_sid, group_sid;
 	struct dentry *parent = path->dentry->d_parent;
-	struct user_namespace *user_ns = mnt_user_ns(path->mnt);
+	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
 	int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
 	int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
 	char *aces_base;
 	bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
 
-	pntsd_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
+	pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
 					    parent, &parent_pntsd);
 	if (pntsd_size <= 0)
 		return -ENOENT;
@@ -1162,7 +1162,7 @@ pass:
 			pntsd_size += sizeof(struct smb_acl) + nt_size;
 		}
 
-		ksmbd_vfs_set_sd_xattr(conn, user_ns,
+		ksmbd_vfs_set_sd_xattr(conn, idmap,
 				       path->dentry, pntsd, pntsd_size);
 		kfree(pntsd);
 	}
@@ -1190,7 +1190,7 @@ bool smb_inherit_flags(int flags, bool is_dir)
 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
 			__le32 *pdaccess, int uid)
 {
-	struct user_namespace *user_ns = mnt_user_ns(path->mnt);
+	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
 	struct smb_ntsd *pntsd = NULL;
 	struct smb_acl *pdacl;
 	struct posix_acl *posix_acls;
@@ -1206,7 +1206,7 @@ int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
 	unsigned short ace_size;
 
 	ksmbd_debug(SMB, "check permission using windows acl\n");
-	pntsd_size = ksmbd_vfs_get_sd_xattr(conn, user_ns,
+	pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
 					    path->dentry, &pntsd);
 	if (pntsd_size <= 0 || !pntsd)
 		goto err_out;
@@ -1296,9 +1296,9 @@ int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
 			pa_entry = posix_acls->a_entries;
 			for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
 				if (pa_entry->e_tag == ACL_USER)
-					id = posix_acl_uid_translate(user_ns, pa_entry);
+					id = posix_acl_uid_translate(idmap, pa_entry);
 				else if (pa_entry->e_tag == ACL_GROUP)
-					id = posix_acl_gid_translate(user_ns, pa_entry);
+					id = posix_acl_gid_translate(idmap, pa_entry);
 				else
 					continue;
 
@@ -1360,14 +1360,14 @@ int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
 	int rc;
 	struct smb_fattr fattr = {{0}};
 	struct inode *inode = d_inode(path->dentry);
-	struct user_namespace *user_ns = mnt_user_ns(path->mnt);
+	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
 	struct iattr newattrs;
 
 	fattr.cf_uid = INVALID_UID;
 	fattr.cf_gid = INVALID_GID;
 	fattr.cf_mode = inode->i_mode;
 
-	rc = parse_sec_desc(user_ns, pntsd, ntsd_len, &fattr);
+	rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr);
 	if (rc)
 		goto out;
 
@@ -1383,17 +1383,17 @@ int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
 	newattrs.ia_valid |= ATTR_MODE;
 	newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
 
-	ksmbd_vfs_remove_acl_xattrs(user_ns, path->dentry);
+	ksmbd_vfs_remove_acl_xattrs(idmap, path->dentry);
 	/* Update posix acls */
 	if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
-		rc = set_posix_acl(user_ns, path->dentry,
+		rc = set_posix_acl(idmap, path->dentry,
 				   ACL_TYPE_ACCESS, fattr.cf_acls);
 		if (rc < 0)
 			ksmbd_debug(SMB,
 				    "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
 				    rc);
 		if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
-			rc = set_posix_acl(user_ns, path->dentry,
+			rc = set_posix_acl(idmap, path->dentry,
 					   ACL_TYPE_DEFAULT, fattr.cf_dacls);
 			if (rc)
 				ksmbd_debug(SMB,
@@ -1403,7 +1403,7 @@ int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
 	}
 
 	inode_lock(inode);
-	rc = notify_change(user_ns, path->dentry, &newattrs, NULL);
+	rc = notify_change(idmap, path->dentry, &newattrs, NULL);
 	inode_unlock(inode);
 	if (rc)
 		goto out;
@@ -1414,8 +1414,8 @@ int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
 
 	if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
 		/* Update WinACL in xattr */
-		ksmbd_vfs_remove_sd_xattrs(user_ns, path->dentry);
-		ksmbd_vfs_set_sd_xattr(conn, user_ns,
+		ksmbd_vfs_remove_sd_xattrs(idmap, path->dentry);
+		ksmbd_vfs_set_sd_xattr(conn, idmap,
 				       path->dentry, pntsd, ntsd_len);
 	}