[PATCH] lsm: constify 'sb' parameter in security_sb_remount()

[Khadija Kamran <kamrankhadijadj@gmail.com>]

The "sb_remount" hook has implementations registered in SELinux and
Landlock. Looking at the function implementations we observe that the
"sb" parameter is not changing.

Mark the "sb" parameter of LSM hook security_sb_remount() as "const"
since it will not be changing in the LSM hook.

Signed-off-by: Khadija Kamran <kamrankhadijadj@gmail.com>
---
 include/linux/lsm_hook_defs.h | 2 +-
 include/linux/security.h      | 2 +-
 security/landlock/fs.c        | 2 +-
 security/security.c           | 2 +-
 security/selinux/hooks.c      | 2 +-
 5 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index 6bb55e61e8e8..dca689c9ac04 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h
@@ -64,7 +64,7 @@ LSM_HOOK(void, LSM_RET_VOID, sb_free_security, struct super_block *sb)
 LSM_HOOK(void, LSM_RET_VOID, sb_free_mnt_opts, void *mnt_opts)
 LSM_HOOK(int, 0, sb_eat_lsm_opts, char *orig, void **mnt_opts)
 LSM_HOOK(int, 0, sb_mnt_opts_compat, struct super_block *sb, void *mnt_opts)
-LSM_HOOK(int, 0, sb_remount, struct super_block *sb, void *mnt_opts)
+LSM_HOOK(int, 0, sb_remount, const struct super_block *sb, void *mnt_opts)
 LSM_HOOK(int, 0, sb_kern_mount, struct super_block *sb)
 LSM_HOOK(int, 0, sb_show_options, struct seq_file *m, struct super_block *sb)
 LSM_HOOK(int, 0, sb_statfs, struct dentry *dentry)
diff --git a/include/linux/security.h b/include/linux/security.h
index e2734e9e44d5..ce08ed7d5437 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -301,7 +301,7 @@ void security_sb_free(struct super_block *sb);
 void security_free_mnt_opts(void **mnt_opts);
 int security_sb_eat_lsm_opts(char *options, void **mnt_opts);
 int security_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts);
-int security_sb_remount(struct super_block *sb, void *mnt_opts);
+int security_sb_remount(const struct super_block *sb, void *mnt_opts);
 int security_sb_kern_mount(struct super_block *sb);
 int security_sb_show_options(struct seq_file *m, struct super_block *sb);
 int security_sb_statfs(struct dentry *dentry);
diff --git a/security/landlock/fs.c b/security/landlock/fs.c
index 1c0c198f6fdb..fabe324922ec 100644
--- a/security/landlock/fs.c
+++ b/security/landlock/fs.c
@@ -1074,7 +1074,7 @@ static int hook_sb_umount(struct vfsmount *const mnt, const int flags)
 	return -EPERM;
 }
 
-static int hook_sb_remount(struct super_block *const sb, void *const mnt_opts)
+static int hook_sb_remount(const struct super_block *const sb, void *const mnt_opts)
 {
 	if (!landlock_get_current_domain())
 		return 0;
diff --git a/security/security.c b/security/security.c
index d5ff7ff45b77..acc8a92ba857 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1289,7 +1289,7 @@ EXPORT_SYMBOL(security_sb_mnt_opts_compat);
  *
  * Return: Returns 0 if permission is granted.
  */
-int security_sb_remount(struct super_block *sb,
+int security_sb_remount(const struct super_block *sb,
 			void *mnt_opts)
 {
 	return call_int_hook(sb_remount, 0, sb, mnt_opts);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 79b4890e9936..e4de42150b87 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2628,7 +2628,7 @@ static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
 	return 0;
 }
 
-static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
+static int selinux_sb_remount(const struct super_block *sb, void *mnt_opts)
 {
 	struct selinux_mnt_opts *opts = mnt_opts;
 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
-- 
2.34.1