ovl: use generic_readlink

[cascardo/linux.git] / fs / overlayfs / inode.c

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index c75625c..50dc214 100644 (file)
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -19,6 +19,7 @@ static int ovl_copy_up_truncate(struct dentry *dentry)
        struct dentry *parent;
        struct kstat stat;
        struct path lowerpath;
+       const struct cred *old_cred;
 
        parent = dget_parent(dentry);
        err = ovl_copy_up(parent);
@@ -26,12 +27,14 @@ static int ovl_copy_up_truncate(struct dentry *dentry)
                goto out_dput_parent;
 
        ovl_path_lower(dentry, &lowerpath);
-       err = vfs_getattr(&lowerpath, &stat);
-       if (err)
-               goto out_dput_parent;
 
-       stat.size = 0;
-       err = ovl_copy_up_one(parent, dentry, &lowerpath, &stat);
+       old_cred = ovl_override_creds(dentry->d_sb);
+       err = vfs_getattr(&lowerpath, &stat);
+       if (!err) {
+               stat.size = 0;
+               err = ovl_copy_up_one(parent, dentry, &lowerpath, &stat);
+       }
+       revert_creds(old_cred);
 
 out_dput_parent:
        dput(parent);
@@ -173,25 +176,6 @@ static const char *ovl_get_link(struct dentry *dentry,
        return p;
 }
 
-static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
-{
-       struct path realpath;
-       struct inode *realinode;
-       const struct cred *old_cred;
-       int err;
-
-       ovl_path_real(dentry, &realpath);
-       realinode = realpath.dentry->d_inode;
-
-       if (!realinode->i_op->readlink)
-               return -EINVAL;
-
-       old_cred = ovl_override_creds(dentry->d_sb);
-       err = realinode->i_op->readlink(realpath.dentry, buf, bufsiz);
-       revert_creds(old_cred);
-       return err;
-}
-
 bool ovl_is_private_xattr(const char *name)
 {
        return strncmp(name, OVL_XATTR_PREFIX,
@@ -378,7 +362,7 @@ static const struct inode_operations ovl_file_inode_operations = {
 static const struct inode_operations ovl_symlink_inode_operations = {
        .setattr        = ovl_setattr,
        .get_link       = ovl_get_link,
-       .readlink       = ovl_readlink,
+       .readlink       = generic_readlink,
        .getattr        = ovl_getattr,
        .setxattr       = generic_setxattr,
        .getxattr       = generic_getxattr,