Re: [PATCH] fat: Fix sb_rdonly() change

From: Joe Perches
Date: Fri Nov 24 2017 - 01:51:44 EST


On Fri, 2017-11-24 at 15:07 +0900, OGAWA Hirofumi wrote:
> Joe Perches <joe@xxxxxxxxxxx> writes:
>
> > On Thu, 2017-11-23 at 15:29 +0900, OGAWA Hirofumi wrote:
> > > Ouch forgot to add stable@
> > >
> > > --
> > > commit bc98a42c1f7d0f886c0c1b75a92a004976a46d9f introduced bug.
> >
> > I think your commit message needs a bit more information.
> >
> > It'd be useful to describe that the introduction of
> > sb_rdonly converted the bitwise & to a boolean and so
> > this conversion and comparison was made defective.
> >
> > Are there any other instances of defective comparisons?
>
> Please ask to that patch author.

The patch author, David Howells, is on the cc list.

btw:

It seems all the the other uses use a (bool) cast of the
(*flags & MS_RDONLY) and a comparison of sb_rdonly(sb).

It would make sense to change the argument type of the
ext[24]_setup_super int read_only arg to bool to match
the sb_rdonly() type.