From: akpm@linux-foundation.org Subject: [patch 10/28] ext2: return -EIO not -ESTALE on directory traversal through deleted inode Date: Tue, 30 Jun 2009 11:41:24 -0700 Message-ID: <200906301841.n5UIfPYi001504@imap1.linux-foundation.org> Cc: akpm@linux-foundation.org, bdonlan@gmail.com, linux-ext4@vger.kernel.org To: torvalds@linux-foundation.org Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:35937 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751917AbZF3Sle (ORCPT ); Tue, 30 Jun 2009 14:41:34 -0400 Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Bryan Donlan ext2_iget() returns -ESTALE if invoked on a deleted inode, in order to report errors to NFS properly. However, in ext[234]_lookup(), this -ESTALE can be propagated to userspace if the filesystem is corrupted such that a directory entry references a deleted inode. This leads to a misleading error message - "Stale NFS file handle" - and confusion on the part of the admin. The bug can be easily reproduced by creating a new filesystem, making a link to an unused inode using debugfs, then mounting and attempting to ls -l said link. This patch thus changes ext2_lookup to return -EIO if it receives -ESTALE from ext2_iget(), as ext2 does for other filesystem metadata corruption; and also invokes the appropriate ext*_error functions when this case is detected. Signed-off-by: Bryan Donlan Cc: Signed-off-by: Andrew Morton --- fs/ext2/namei.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff -puN fs/ext2/namei.c~ext2-return-eio-not-estale-on-directory-traversal-through-deleted-inode fs/ext2/namei.c --- a/fs/ext2/namei.c~ext2-return-eio-not-estale-on-directory-traversal-through-deleted-inode +++ a/fs/ext2/namei.c @@ -66,8 +66,16 @@ static struct dentry *ext2_lookup(struct inode = NULL; if (ino) { inode = ext2_iget(dir->i_sb, ino); - if (IS_ERR(inode)) - return ERR_CAST(inode); + if (unlikely(IS_ERR(inode))) { + if (PTR_ERR(inode) == -ESTALE) { + ext2_error(dir->i_sb, __func__, + "deleted inode referenced: %lu", + ino); + return ERR_PTR(-EIO); + } else { + return ERR_CAST(inode); + } + } } return d_splice_alias(inode, dentry); } _