Commit 44805b0e authored Nov 12, 2019 by Pavel Shilovsky Committed by Steve French Nov 25, 2019

CIFS: Respect O_SYNC and O_DIRECT flags during reconnect



Currently the client translates O_SYNC and O_DIRECT flags
into corresponding SMB create options when openning a file.
The problem is that on reconnect when the file is being
re-opened the client doesn't set those flags and it causes
a server to reject re-open requests because create options
don't match. The latter means that any subsequent system
call against that open file fail until a share is re-mounted.

Fix this by properly setting SMB create options when
re-openning files after reconnects.

Fixes: 1013e760: ("SMB3: Don't ignore O_SYNC/O_DSYNC and O_DIRECT flags")
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

parent 037d0507

fs/cifs/file.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -728,6 +728,13 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
		if (backup_cred(cifs_sb))
		create_options \|= CREATE_OPEN_BACKUP_INTENT;

		/* O_SYNC also has bit for O_DSYNC so following check picks up either */
		if (cfile->f_flags & O_SYNC)
		create_options \|= CREATE_WRITE_THROUGH;

		if (cfile->f_flags & O_DIRECT)
		create_options \|= CREATE_NO_BUFFER;

		if (server->ops->get_lease_key)
		server->ops->get_lease_key(inode, &cfile->fid);

Admin message