security: new security_inode_init_security API adds function callback

This patch changes the security_inode_init_security API by adding a
filesystem specific callback to write security extended attributes.
This change is in preparation for supporting the initialization of
multiple LSM xattrs and the EVM xattr.  Initially the callback function
walks an array of xattrs, writing each xattr separately, but could be
optimized to write multiple xattrs at once.

For existing security_inode_init_security() calls, which have not yet
been converted to use the new callback function, such as those in
reiserfs and ocfs2, this patch defines security_old_inode_init_security().

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>

1 files changed, 24 insertions, 14 deletions

diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 81ecf9c0bf0..194fb22ef79 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -7185,20 +7185,9 @@ int ocfs2_init_security_and_acl(struct inode *dir,
 {
         int ret = 0;
         struct buffer_head *dir_bh = NULL;
-        struct ocfs2_security_xattr_info si = {
-                .enable = 1,
-        };
 
-        ret = ocfs2_init_security_get(inode, dir, qstr, &si);
+        ret = ocfs2_init_security_get(inode, dir, qstr, NULL);
         if (!ret) {
-                ret = ocfs2_xattr_set(inode, OCFS2_XATTR_INDEX_SECURITY,
-                                      si.name, si.value, si.value_len,
-                                      XATTR_CREATE);
-                if (ret) {
-                        mlog_errno(ret);
-                        goto leave;
-                }
-        } else if (ret != -EOPNOTSUPP) {
                 mlog_errno(ret);
                 goto leave;
         }
@@ -7255,6 +7244,22 @@ static int ocfs2_xattr_security_set(struct dentry *dentry, const char *name,
                                name, value, size, flags);
 }
 
+int ocfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+                     void *fs_info)
+{
+        const struct xattr *xattr;
+        int err = 0;
+
+        for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+                err = ocfs2_xattr_set(inode, OCFS2_XATTR_INDEX_SECURITY,
+                                      xattr->name, xattr->value,
+                                      xattr->value_len, XATTR_CREATE);
+                if (err)
+                        break;
+        }
+        return err;
+}
+
 int ocfs2_init_security_get(struct inode *inode,
                             struct inode *dir,
                             const struct qstr *qstr,
@@ -7263,8 +7268,13 @@ int ocfs2_init_security_get(struct inode *inode,
         /* check whether ocfs2 support feature xattr */
         if (!ocfs2_supports_xattr(OCFS2_SB(dir->i_sb)))
                 return -EOPNOTSUPP;
-        return security_inode_init_security(inode, dir, qstr, &si->name,
-                                            &si->value, &si->value_len);
+        if (si)
+                return security_old_inode_init_security(inode, dir, qstr,
+                                                        &si->name, &si->value,
+                                                        &si->value_len);
+
+        return security_inode_init_security(inode, dir, qstr,
+                                            &ocfs2_initxattrs, NULL);
 }
 
 int ocfs2_init_security_set(handle_t *handle,