linux-kernel - Re: [PATCH] fuse:rely on fuse_perm for exec when no mode bits set

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Date:   Mon, 27 Apr 2020 19:16:08 +0530
From:   Chakra Divi <chakragithub@...il.com>
To:     Miklos Szeredi <miklos@...redi.hu>
Cc:     linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] fuse:rely on fuse_perm for exec when no mode bits set

On Tue, Apr 21, 2020 at 4:21 PM Chakra Divi <chakragithub@...il.com> wrote:
>
> On Mon, Apr 20, 2020 at 4:55 PM Miklos Szeredi <miklos@...redi.hu> wrote:
> >
> > On Wed, Apr 1, 2020 at 11:31 AM Chakra Divi <chakragithub@...il.com> wrote:
> > >
> > > In current code, for exec we are checking mode bits
> > > for x bit set even though the fuse_perm_getattr returns
> > > success. Changes in this patch avoids mode bit explicit
> > > check, leaves the exec checking to fuse file system
> > > in uspace.
> >
> > Why is this needed?
>
> Thanks for responding Miklos. We have an use case with our remote file
> system mounted on fuse , where permissions checks will happen remotely
> without the need of mode bits. In case of read, write it worked
> without issues. But for executable files, we found that fuse kernel is
> explicitly checking 'x' mode bit set on the file. We want this
> checking also to be pushed to remote instead of kernel doing it - so
> modified the kernel code to send getattr op to usespace in exec case
> too.

Any help on this Miklos....

Thanks,
Chakra
> > Thanks,
> > Miklos