Re: [PATCH] ksmbd: use F_SETLK to force vfs_file_lock() to return asynchronously

From: Namjae Jeon
Date: Tue Dec 21 2021 - 07:02:20 EST


2021-12-19 18:34 GMT+09:00, Vasily Averin <vvs@xxxxxxxxxxxxx>:
> To avoid possible deadlock ksmbd should process locks asynchronously.
> Callers expecting vfs_file_locks() to return asynchronously should only
> use F_SETLK, not F_SETLKW.
Should I check this patch instead of
[PATCH] ksmbd: force "fail immediately" flag on fs with its own ->lock ?

>
> Signed-off-by: Vasily Averin <vvs@xxxxxxxxxxxxx>
> ---
> fs/ksmbd/smb2pdu.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> index 0c020deb76bb..34f333549767 100644
> --- a/fs/ksmbd/smb2pdu.c
> +++ b/fs/ksmbd/smb2pdu.c
> @@ -6646,13 +6646,13 @@ static int smb2_set_flock_flags(struct file_lock
> *flock, int flags)
> switch (flags) {
> case SMB2_LOCKFLAG_SHARED:
> ksmbd_debug(SMB, "received shared request\n");
> - cmd = F_SETLKW;
> + cmd = F_SETLK;
> flock->fl_type = F_RDLCK;
> flock->fl_flags |= FL_SLEEP;
> break;
> case SMB2_LOCKFLAG_EXCLUSIVE:
> ksmbd_debug(SMB, "received exclusive request\n");
> - cmd = F_SETLKW;
> + cmd = F_SETLK;
> flock->fl_type = F_WRLCK;
> flock->fl_flags |= FL_SLEEP;
> break;
> --
> 2.25.1
>
>