Re: [PATCH] xfs: Fix xfs_dir2_sf_entry_t size check

[Darrick J. Wong]

On Mon, Jan 13, 2020 at 03:06:50PM +0100, Arnd Bergmann wrote:
> On Mon, Jan 13, 2020 at 2:58 PM Christoph Hellwig <hch@xxxxxx> wrote:
> >
> > On Mon, Jan 13, 2020 at 02:55:15PM +0100, Arnd Bergmann wrote:
> > > With ARM OABI (which you get when EABI is disabled), structures are padded
> > > to multiples of 32 bits. See commits 8353a649f577 ("xfs: kill
> > > xfs_dir2_sf_off_t")
> > > and aa2dd0ad4d6d ("xfs: remove __arch_pack"). Those could be partially
> > > reverted to fix it again, but it doesn't seem worth it as there is
> > > probably nobody
> > > running XFS on OABI machines (actually with the build failure we can
> > > be fairly sure there isn't ;-).
> >
> > Or just try adding a __packed to the xfs_dir2_sf_entry definition?
> 
> Yes, that should be correct on all architectures, and I just noticed
> that this is what we already have on xfs_dir2_sf_hdr_t directly
> above it for the same reason.

Yeah, that sounds like a reasonable way forward, short of cleaning out
all the array[0] cr^Hode... ;)

To the original submitter: can you add __packed to the structure
definition and (assuming it passes oabi compilation) send that to the
list, please?

--D

> 
>        Arnd