fs: port acl to mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("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>

5 files changed, 26 insertions, 26 deletions

diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 99f7bd8af19a..4e5adddb3577 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -610,7 +610,7 @@ int evm_inode_removexattr(struct mnt_idmap *idmap,
 }
 
 #ifdef CONFIG_FS_POSIX_ACL
-static int evm_inode_set_acl_change(struct user_namespace *mnt_userns,
+static int evm_inode_set_acl_change(struct mnt_idmap *idmap,
 				    struct dentry *dentry, const char *name,
 				    struct posix_acl *kacl)
 {
@@ -622,14 +622,14 @@ static int evm_inode_set_acl_change(struct user_namespace *mnt_userns,
 	if (!kacl)
 		return 1;
 
-	rc = posix_acl_update_mode(mnt_userns, inode, &mode, &kacl);
+	rc = posix_acl_update_mode(idmap, inode, &mode, &kacl);
 	if (rc || (inode->i_mode != mode))
 		return 1;
 
 	return 0;
 }
 #else
-static inline int evm_inode_set_acl_change(struct user_namespace *mnt_userns,
+static inline int evm_inode_set_acl_change(struct mnt_idmap *idmap,
 					   struct dentry *dentry,
 					   const char *name,
 					   struct posix_acl *kacl)
@@ -640,7 +640,7 @@ static inline int evm_inode_set_acl_change(struct user_namespace *mnt_userns,
 
 /**
  * evm_inode_set_acl - protect the EVM extended attribute from posix acls
- * @mnt_userns: user namespace of the idmapped mount
+ * @idmap: idmap of the idmapped mount
  * @dentry: pointer to the affected dentry
  * @acl_name: name of the posix acl
  * @kacl: pointer to the posix acls
@@ -649,7 +649,7 @@ static inline int evm_inode_set_acl_change(struct user_namespace *mnt_userns,
  * and 'security.evm' xattr updated, unless the existing 'security.evm' is
  * valid.
  */
-int evm_inode_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry,
+int evm_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
 		      const char *acl_name, struct posix_acl *kacl)
 {
 	enum integrity_status evm_status;
@@ -678,7 +678,7 @@ int evm_inode_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry,
 		return 0;
 
 	if (evm_status == INTEGRITY_PASS_IMMUTABLE &&
-	    !evm_inode_set_acl_change(mnt_userns, dentry, acl_name, kacl))
+	    !evm_inode_set_acl_change(idmap, dentry, acl_name, kacl))
 		return 0;
 
 	if (evm_status != INTEGRITY_PASS_IMMUTABLE)
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 4078a9ad8531..555342d337f9 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -774,7 +774,7 @@ int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
 	return result;
 }
 
-int ima_inode_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry,
+int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
 		      const char *acl_name, struct posix_acl *kacl)
 {
 	if (evm_revalidate_status(acl_name))
diff --git a/security/security.c b/security/security.c
index 7e7a12142854..4e1150c44ab7 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1400,7 +1400,7 @@ int security_inode_setxattr(struct mnt_idmap *idmap,
 	return evm_inode_setxattr(idmap, dentry, name, value, size);
 }
 
-int security_inode_set_acl(struct user_namespace *mnt_userns,
+int security_inode_set_acl(struct mnt_idmap *idmap,
 			   struct dentry *dentry, const char *acl_name,
 			   struct posix_acl *kacl)
 {
@@ -1408,38 +1408,38 @@ int security_inode_set_acl(struct user_namespace *mnt_userns,
 
 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
 		return 0;
-	ret = call_int_hook(inode_set_acl, 0, mnt_userns, dentry, acl_name,
+	ret = call_int_hook(inode_set_acl, 0, idmap, dentry, acl_name,
 			    kacl);
 	if (ret)
 		return ret;
-	ret = ima_inode_set_acl(mnt_userns, dentry, acl_name, kacl);
+	ret = ima_inode_set_acl(idmap, dentry, acl_name, kacl);
 	if (ret)
 		return ret;
-	return evm_inode_set_acl(mnt_userns, dentry, acl_name, kacl);
+	return evm_inode_set_acl(idmap, dentry, acl_name, kacl);
 }
 
-int security_inode_get_acl(struct user_namespace *mnt_userns,
+int security_inode_get_acl(struct mnt_idmap *idmap,
 			   struct dentry *dentry, const char *acl_name)
 {
 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
 		return 0;
-	return call_int_hook(inode_get_acl, 0, mnt_userns, dentry, acl_name);
+	return call_int_hook(inode_get_acl, 0, idmap, dentry, acl_name);
 }
 
-int security_inode_remove_acl(struct user_namespace *mnt_userns,
+int security_inode_remove_acl(struct mnt_idmap *idmap,
 			      struct dentry *dentry, const char *acl_name)
 {
 	int ret;
 
 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
 		return 0;
-	ret = call_int_hook(inode_remove_acl, 0, mnt_userns, dentry, acl_name);
+	ret = call_int_hook(inode_remove_acl, 0, idmap, dentry, acl_name);
 	if (ret)
 		return ret;
-	ret = ima_inode_remove_acl(mnt_userns, dentry, acl_name);
+	ret = ima_inode_remove_acl(idmap, dentry, acl_name);
 	if (ret)
 		return ret;
-	return evm_inode_remove_acl(mnt_userns, dentry, acl_name);
+	return evm_inode_remove_acl(idmap, dentry, acl_name);
 }
 
 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 706bb440f837..f32fa3359502 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3241,20 +3241,20 @@ static int selinux_inode_setxattr(struct mnt_idmap *idmap,
 			    &ad);
 }
 
-static int selinux_inode_set_acl(struct user_namespace *mnt_userns,
+static int selinux_inode_set_acl(struct mnt_idmap *idmap,
 				 struct dentry *dentry, const char *acl_name,
 				 struct posix_acl *kacl)
 {
 	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
 }
 
-static int selinux_inode_get_acl(struct user_namespace *mnt_userns,
+static int selinux_inode_get_acl(struct mnt_idmap *idmap,
 				 struct dentry *dentry, const char *acl_name)
 {
 	return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
 }
 
-static int selinux_inode_remove_acl(struct user_namespace *mnt_userns,
+static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
 				    struct dentry *dentry, const char *acl_name)
 {
 	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 306c921759f6..cfcbb748da25 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1394,14 +1394,14 @@ static int smack_inode_removexattr(struct mnt_idmap *idmap,
 
 /**
  * smack_inode_set_acl - Smack check for setting posix acls
- * @mnt_userns: the userns attached to the mnt this request came from
+ * @idmap: idmap of the mnt this request came from
  * @dentry: the object
  * @acl_name: name of the posix acl
  * @kacl: the posix acls
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
-static int smack_inode_set_acl(struct user_namespace *mnt_userns,
+static int smack_inode_set_acl(struct mnt_idmap *idmap,
 			       struct dentry *dentry, const char *acl_name,
 			       struct posix_acl *kacl)
 {
@@ -1418,13 +1418,13 @@ static int smack_inode_set_acl(struct user_namespace *mnt_userns,
 
 /**
  * smack_inode_get_acl - Smack check for getting posix acls
- * @mnt_userns: the userns attached to the mnt this request came from
+ * @idmap: idmap of the mnt this request came from
  * @dentry: the object
  * @acl_name: name of the posix acl
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
-static int smack_inode_get_acl(struct user_namespace *mnt_userns,
+static int smack_inode_get_acl(struct mnt_idmap *idmap,
 			       struct dentry *dentry, const char *acl_name)
 {
 	struct smk_audit_info ad;
@@ -1440,13 +1440,13 @@ static int smack_inode_get_acl(struct user_namespace *mnt_userns,
 
 /**
  * smack_inode_remove_acl - Smack check for getting posix acls
- * @mnt_userns: the userns attached to the mnt this request came from
+ * @idmap: idmap of the mnt this request came from
  * @dentry: the object
  * @acl_name: name of the posix acl
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
-static int smack_inode_remove_acl(struct user_namespace *mnt_userns,
+static int smack_inode_remove_acl(struct mnt_idmap *idmap,
 				  struct dentry *dentry, const char *acl_name)
 {
 	struct smk_audit_info ad;