evm: imbed evm_inode_post_setattr

Changing the inode's metadata may require the 'security.evm' extended
attribute to be re-calculated and updated.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>

fs/attr.c

@@ -13,6 +13,7 @@
 #include <linux/fsnotify.h>
 #include <linux/fcntl.h>
 #include <linux/security.h>
+#include <linux/evm.h>
 
 /**
  * inode_change_ok - check if attribute changes to an inode are allowed
@@ -243,8 +244,10 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
 	if (ia_valid & ATTR_SIZE)
 		up_write(&dentry->d_inode->i_alloc_sem);
 
-	if (!error)
+	if (!error) {
 		fsnotify_change(dentry, ia_valid);
+		evm_inode_post_setattr(dentry, ia_valid);
+	}
 
 	return error;
 }

include/linux/evm.h

@@ -15,6 +15,7 @@ extern enum integrity_status evm_verifyxattr(struct dentry *dentry,
 					     const char *xattr_name,
 					     void *xattr_value,
 					     size_t xattr_value_len);
+extern void evm_inode_post_setattr(struct dentry *dentry, int ia_valid);
 extern int evm_inode_setxattr(struct dentry *dentry, const char *name,
 			      const void *value, size_t size);
 extern void evm_inode_post_setxattr(struct dentry *dentry,
@@ -35,6 +36,11 @@ static inline enum integrity_status evm_verifyxattr(struct dentry *dentry,
 }
 #endif
 
+static inline void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
+{
+	return;
+}
+
 static inline int evm_inode_setxattr(struct dentry *dentry, const char *name,
 				     const void *value, size_t size)
 {