On Thu 10-08-23 20:58:16, Amir Goldstein wrote:
> On Tue, Aug 8, 2023 at 12:19 PM Su Hui <suhui@xxxxxxxxxxxx> wrote:
> >
> > smatch error:
> > fs/notify/fanotify/fanotify_user.c:462 copy_fid_info_to_user():
> > we previously assumed 'fh' could be null (see line 421)
> >
> > Fixes: afc894c784c8 ("fanotify: Store fanotify handles differently")
> > Signed-off-by: Su Hui <suhui@xxxxxxxxxxxx>'
>
> Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
I'm sorry but this has somehow fallen through the cracks.
> > diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
> > index f69c451018e3..5a5487ae2460 100644
> > --- a/fs/notify/fanotify/fanotify_user.c
> > +++ b/fs/notify/fanotify/fanotify_user.c
> > @@ -459,12 +459,13 @@ static int copy_fid_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh,
> > if (WARN_ON_ONCE(len < sizeof(handle)))
> > return -EFAULT;
> >
> > - handle.handle_type = fh->type;
> > handle.handle_bytes = fh_len;
Well, if passed 'fh' is NULL, we have problems later in the function
anyway. E.g. in fanotify_fh_buf() a few lines below. So I think this needs
a bit more work that just this small fixup...
Honza
> >
> > /* Mangle handle_type for bad file_handle */
> > if (!fh_len)
> > handle.handle_type = FILEID_INVALID;
> > + else
> > + handle.handle_type = fh->type;
> >
> > if (copy_to_user(buf, &handle, sizeof(handle)))
> > return -EFAULT;
> > --
> > 2.30.2
> >
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
