This is a note to let you know that I've just added the patch titled
CIFS: Respect O_SYNC and O_DIRECT flags during reconnect
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cifs-respect-o_sync-and-o_direct-flags-during-reconnect.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 44805b0e62f15e90d233485420e1847133716bdc Mon Sep 17 00:00:00 2001
From: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
Date: Tue, 12 Nov 2019 17:16:35 -0800
Subject: CIFS: Respect O_SYNC and O_DIRECT flags during reconnect
From: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
commit 44805b0e62f15e90d233485420e1847133716bdc upstream.
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: 1013e760d10e6: ("SMB3: Don't ignore O_SYNC/O_DSYNC and O_DIRECT flags")
Cc: Stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/cifs/file.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -722,6 +722,13 @@ cifs_reopen_file(struct cifsFileInfo *cf
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);
Patches currently in stable-queue which might be from pshilov@xxxxxxxxxxxxx are
queue-4.9/cifs-respect-o_sync-and-o_direct-flags-during-reconnect.patch
queue-4.9/cifs-fix-null-pointer-dereference-in-smb2_push_mandatory_locks.patch
queue-4.9/cifs-fix-smb2-oplock-break-processing.patch
