From bd04b9192e1ff6859d6b3906e91cfd5c9b0ad55b Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Tue, 30 Aug 2022 22:49:36 +0800 Subject: ceph: fail the open_by_handle_at() if the dentry is being unlinked MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When unlinking a file the kclient will send a unlink request to MDS by holding the dentry reference, and then the MDS will return 2 replies, which are unsafe reply and a deferred safe reply. After the unsafe reply received the kernel will return and succeed the unlink request to user space apps. Only when the safe reply received the dentry's reference will be released. Or the dentry will only be unhashed from dcache. But when the open_by_handle_at() begins to open the unlinked files it will succeed. The inode->i_count couldn't be used to check whether the inode is opened or not. Link: https://tracker.ceph.com/issues/56524 Signed-off-by: Xiubo Li Reviewed-by: Jeff Layton Reviewed-by: Luís Henriques Tested-by: Luís Henriques Signed-off-by: Ilya Dryomov --- fs/ceph/export.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/ceph') diff --git a/fs/ceph/export.c b/fs/ceph/export.c index e0fa66ac8b9f..f780e4e0d062 100644 --- a/fs/ceph/export.c +++ b/fs/ceph/export.c @@ -181,6 +181,7 @@ struct inode *ceph_lookup_inode(struct super_block *sb, u64 ino) static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino) { struct inode *inode = __lookup_inode(sb, ino); + struct ceph_inode_info *ci = ceph_inode(inode); int err; if (IS_ERR(inode)) @@ -192,7 +193,7 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino) return ERR_PTR(err); } /* -ESTALE if inode as been unlinked and no file is open */ - if ((inode->i_nlink == 0) && (atomic_read(&inode->i_count) == 1)) { + if ((inode->i_nlink == 0) && !__ceph_is_file_opened(ci)) { iput(inode); return ERR_PTR(-ESTALE); } -- cgit v1.2.3