Re: [PATCH v2 1/3] fanotify: Ensure consistent variable type for response

From: Richard Guy Briggs
Date: Tue May 03 2022 - 17:10:37 EST


On 2022-05-02 20:16, Paul Moore wrote:
> On Thu, Apr 28, 2022 at 8:45 PM Richard Guy Briggs <rgb@xxxxxxxxxx> wrote:
> >
> > The user space API for the response variable is __u32. This patch makes
> > sure that the whole path through the kernel uses __u32 so that there is
> > no sign extension or truncation of the user space response.
> >
> > Suggested-by: Steve Grubb <sgrubb@xxxxxxxxxx>
> > Link: https://lore.kernel.org/r/12617626.uLZWGnKmhe@x2
> > Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
> > Link: https://lore.kernel.org/r/aa98a3ad00666a6fc0ce411755de4a1a60f5c0cd.1651174324.git.rgb@xxxxxxxxxx
> > ---
> > fs/notify/fanotify/fanotify.h | 2 +-
> > fs/notify/fanotify/fanotify_user.c | 6 +++---
> > 2 files changed, 4 insertions(+), 4 deletions(-)
>
> It seems like audit_fanotify()/__audit_fanotify() should also be
> changed, yes? Granted, in this case it's an unsigned int to u32
> conversion so not really all that critical, but if you are going to
> update the fanotify code you might as well update the audit code as
> well for the sake of completeness.

Yes, that was somewhere in the back of my mind but forgot to come back
to it. Thanks for catching that.

> paul-moore.com

- RGB

--
Richard Guy Briggs <rgb@xxxxxxxxxx>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
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