fs: port acl to const mnt_idmap

Convert to const struct mnt_idmap.

A mount's idmapping is immutable. The only thing that is allowed to be
modified afterwards is the reference count and that is hidden behind
mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads
from the idmapping. This is the same model that struct cred uses and the
idmapping is also rather sensitive.

So make the idmap argument const wherever we can. The conversion is done
from the bottom up so callers can continue to pass a non-const pointer
to a const parameter until the conversion is finished.

No functional changes.

Link: https://patch.msgid.link/20260901-work-idmap-const-v1-11-54ccd48e100b@kernel.org
Acked-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Seth Forshee <sforshee@kernel.org>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>

5 files changed, 17 insertions, 17 deletions

diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 06e187c9912d..aaf228ebed7c 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -652,7 +652,7 @@ static int evm_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry,
 }
 
 #ifdef CONFIG_FS_POSIX_ACL
-static int evm_inode_set_acl_change(struct mnt_idmap *idmap,
+static int evm_inode_set_acl_change(const struct mnt_idmap *idmap,
 				    struct dentry *dentry, const char *name,
 				    struct posix_acl *kacl)
 {
@@ -671,7 +671,7 @@ static int evm_inode_set_acl_change(struct mnt_idmap *idmap,
 	return 0;
 }
 #else
-static inline int evm_inode_set_acl_change(struct mnt_idmap *idmap,
+static inline int evm_inode_set_acl_change(const struct mnt_idmap *idmap,
 					   struct dentry *dentry,
 					   const char *name,
 					   struct posix_acl *kacl)
@@ -693,7 +693,7 @@ static inline int evm_inode_set_acl_change(struct mnt_idmap *idmap,
  *
  * Return: zero on success, -EPERM on failure.
  */
-static int evm_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
+static int evm_inode_set_acl(const struct mnt_idmap *idmap, struct dentry *dentry,
 			     const char *acl_name, struct posix_acl *kacl)
 {
 	enum integrity_status evm_status;
@@ -745,7 +745,7 @@ static int evm_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
  *
  * Return: zero on success, -EPERM on failure.
  */
-static int evm_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry,
+static int evm_inode_remove_acl(const struct mnt_idmap *idmap, struct dentry *dentry,
 				const char *acl_name)
 {
 	return evm_inode_set_acl(idmap, dentry, acl_name, NULL);
@@ -926,7 +926,7 @@ static void evm_inode_post_removexattr(struct dentry *dentry,
  * Update the 'security.evm' xattr with the EVM HMAC re-calculated after
  * removing posix acls.
  */
-static inline void evm_inode_post_remove_acl(struct mnt_idmap *idmap,
+static inline void evm_inode_post_remove_acl(const struct mnt_idmap *idmap,
 					     struct dentry *dentry,
 					     const char *acl_name)
 {
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 6b21db789ef1..1aed041c127a 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -790,7 +790,7 @@ static int ima_inode_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,
 	return result;
 }
 
-static int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
+static int ima_inode_set_acl(const struct mnt_idmap *idmap, struct dentry *dentry,
 			     const char *acl_name, struct posix_acl *kacl)
 {
 	if (evm_revalidate_status(acl_name))
@@ -815,7 +815,7 @@ static int ima_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry,
 	return result;
 }
 
-static int ima_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry,
+static int ima_inode_remove_acl(const struct mnt_idmap *idmap, struct dentry *dentry,
 				const char *acl_name)
 {
 	return ima_inode_set_acl(idmap, dentry, acl_name, NULL);
diff --git a/security/security.c b/security/security.c
index 2ee276ab15c5..e81dcda3050b 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1953,7 +1953,7 @@ int security_inode_setxattr(struct mnt_idmap *idmap,
  *
  * Return: Returns 0 if permission is granted.
  */
-int security_inode_set_acl(struct mnt_idmap *idmap,
+int security_inode_set_acl(const struct mnt_idmap *idmap,
 			   struct dentry *dentry, const char *acl_name,
 			   struct posix_acl *kacl)
 {
@@ -1990,7 +1990,7 @@ void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name,
  *
  * Return: Returns 0 if permission is granted.
  */
-int security_inode_get_acl(struct mnt_idmap *idmap,
+int security_inode_get_acl(const struct mnt_idmap *idmap,
 			   struct dentry *dentry, const char *acl_name)
 {
 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
@@ -2009,7 +2009,7 @@ int security_inode_get_acl(struct mnt_idmap *idmap,
  *
  * Return: Returns 0 if permission is granted.
  */
-int security_inode_remove_acl(struct mnt_idmap *idmap,
+int security_inode_remove_acl(const struct mnt_idmap *idmap,
 			      struct dentry *dentry, const char *acl_name)
 {
 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
@@ -2026,7 +2026,7 @@ int security_inode_remove_acl(struct mnt_idmap *idmap,
  * Update inode security data after successfully removing posix acls on
  * @dentry in @idmap. The posix acls are identified by @acl_name.
  */
-void security_inode_post_remove_acl(struct mnt_idmap *idmap,
+void security_inode_post_remove_acl(const struct mnt_idmap *idmap,
 				    struct dentry *dentry, const char *acl_name)
 {
 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 035aaf113d1d..672d6374d8b0 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3453,20 +3453,20 @@ static int selinux_inode_setxattr(struct mnt_idmap *idmap,
 			    &ad);
 }
 
-static int selinux_inode_set_acl(struct mnt_idmap *idmap,
+static int selinux_inode_set_acl(const 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 mnt_idmap *idmap,
+static int selinux_inode_get_acl(const 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 mnt_idmap *idmap,
+static int selinux_inode_remove_acl(const 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 8e88ac65fd7f..244cdb49e928 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1543,7 +1543,7 @@ static int smack_inode_removexattr(struct mnt_idmap *idmap,
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
-static int smack_inode_set_acl(struct mnt_idmap *idmap,
+static int smack_inode_set_acl(const struct mnt_idmap *idmap,
 			       struct dentry *dentry, const char *acl_name,
 			       struct posix_acl *kacl)
 {
@@ -1566,7 +1566,7 @@ static int smack_inode_set_acl(struct mnt_idmap *idmap,
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
-static int smack_inode_get_acl(struct mnt_idmap *idmap,
+static int smack_inode_get_acl(const struct mnt_idmap *idmap,
 			       struct dentry *dentry, const char *acl_name)
 {
 	struct smk_audit_info ad;
@@ -1588,7 +1588,7 @@ static int smack_inode_get_acl(struct mnt_idmap *idmap,
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
-static int smack_inode_remove_acl(struct mnt_idmap *idmap,
+static int smack_inode_remove_acl(const struct mnt_idmap *idmap,
 				  struct dentry *dentry, const char *acl_name)
 {
 	struct smk_audit_info ad;