Re: [PATCH] fs: fuse: check return value of fuse_simple_request

[Cengiz Can]

On 2020-01-20 16:39, Miklos Szeredi wrote:
> On Mon, Jan 20, 2020 at 1:13 PM Cengiz Can <cengiz@xxxxxxxxxx> wrote:
> > In `fs/fuse/file.c` `fuse_simple_request` is used in multiple places,
> > with its return value properly checked for possible errors.
> >
> > However the usage on `fuse_file_put` ignores its return value. And the
> > following `fuse_release_end` call used hard-coded error value of `0`.
> >
> > This triggers a warning in static analyzers and such.
> >
> > I've added a variable to capture `fuse_simple_request` result and 
> > passed
> > that to `fuse_release_end` instead.
>
> Which then goes on to ignore the error, so we are exactly where we
> were with some added obscurity, which will be noticed by the next
> generation of static analyzer, when you'd come up with an even more
> obscure way to ignore the error, etc...  This leads to nowhere.

I got your point. Thanks for explaining.

> If this matters (not sure) then we'll need a notation to ignore the
> return value.  Does casting to (void) work?

It should probably work for the sake of silencing the analyzer but I 
think
it would be easier to just ignore the warning and mark is as 
unimportant.

IMHO code should be as readable as possible. So not point in casting it.

If `fuse_simple_request` errors are very rare, we can ignore this patch.

Thank you

> Thanks,
> Miklos

--
Cengiz Can
@cengiz_io