security: Make inode argument of inode_getsecurity non-const

Make the inode argument of the inode_getsecurity hook non-const so that
we can use it to revalidate invalid security labels.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>

include/linux/lsm_hooks.h

@@ -1413,7 +1413,7 @@ union security_list_options {
 	int (*inode_removexattr)(struct dentry *dentry, const char *name);
 	int (*inode_need_killpriv)(struct dentry *dentry);
 	int (*inode_killpriv)(struct dentry *dentry);
-	int (*inode_getsecurity)(const struct inode *inode, const char *name,
+	int (*inode_getsecurity)(struct inode *inode, const char *name,
 					void **buffer, bool alloc);
 	int (*inode_setsecurity)(struct inode *inode, const char *name,
 					const void *value, size_t size,

include/linux/security.h

@@ -270,7 +270,7 @@ int security_inode_listxattr(struct dentry *dentry);
 int security_inode_removexattr(struct dentry *dentry, const char *name);
 int security_inode_need_killpriv(struct dentry *dentry);
 int security_inode_killpriv(struct dentry *dentry);
-int security_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc);
+int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc);
 int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags);
 int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size);
 void security_inode_getsecid(const struct inode *inode, u32 *secid);
@@ -719,7 +719,7 @@ static inline int security_inode_killpriv(struct dentry *dentry)
 	return cap_inode_killpriv(dentry);
 }
 
-static inline int security_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
+static inline int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
 {
 	return -EOPNOTSUPP;
 }

security/security.c

@@ -697,7 +697,7 @@ int security_inode_killpriv(struct dentry *dentry)
 	return call_int_hook(inode_killpriv, 0, dentry);
 }
 
-int security_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
+int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
 {
 	if (unlikely(IS_PRIVATE(inode)))
 		return -EOPNOTSUPP;

security/selinux/hooks.c

@@ -3108,7 +3108,7 @@ static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
  *
  * Permission check is handled by selinux_inode_getxattr hook.
  */
-static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
+static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
 {
 	u32 size;
 	int error;

security/smack/smack_lsm.c

@@ -1465,7 +1465,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
  *
  * Returns the size of the attribute or an error code
  */
-static int smack_inode_getsecurity(const struct inode *inode,
+static int smack_inode_getsecurity(struct inode *inode,
 				   const char *name, void **buffer,
 				   bool alloc)
 {