[PATCH 3.16 042/136] CIFS: Gracefully handle QueryInfo errors during open

Ben Hutchings
2019-12-17T00:57:40Z

From: Pavel Shilovsky <piastryyy@gmail.com>

commit 30573a82fb179420b8aac30a3a3595aa96a93156 upstream.

Currently if the client identifies problems when processing
metadata returned in CREATE response, the open handle is being
leaked. This causes multiple problems like a file missing a lease
break by that client which causes high latencies to other clients
accessing the file. Another side-effect of this is that the file
can't be deleted.

Fix this by closing the file after the client hits an error after
the file was opened and the open descriptor wasn't returned to
the user space. Also convert -ESTALE to -EOPENSTALE to allow
the VFS to revalidate a dentry and retry the open.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
fs/cifs/file.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -253,6 +253,12 @@ cifs_nt_open(char *full_path, struct ino
rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
xid, fid);

+ if (rc) {
+ server->ops->close(xid, tcon, fid);
+ if (rc == -ESTALE)
+ rc = -EOPENSTALE;
+ }
+
out:
kfree(buf);
return rc;