Re: [PATCH v5 7/8] fat (exportfs): rebuild directory-inode if fat_dget() fails

[OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>]

Namjae Jeon <linkinjeon@gmail.com> writes:

>>>> This became much better than before. However, we have to consolidate the
>>>> code with fat_search_long() finally.
>>>>
>>>> E.g. this version is having the issue already fixed. If there is
>>>> corruption in fat cluster-chain, it lead to infinite
>>>> loop. fat_get_cluster() checks infinite loop by limit.
>>> since, the focus this time was for NFS functionality for FAT (removing
>>> ESTALE error). The changes were made in that context.
>>>
>>> Later, we can make the changes as part of code reorganizing which can
>>> be controlled via. Separate patches which do not have any impact on
>>> default functionality and verification can be carried out in that
>>> scope.
>>
>> Right. But non-production code shouldn't go into linus tree. I meant, we
>> can test this patch series, but not yet production quality.
> Is there any other thing which seems potential issue than offsetof()?
> if yes, which problem didn't lead to production quality do you think ?
>
> +#define FAT_FID_SIZE_WITHOUT_PARENT (offsetof(struct fat_fid, \
> +					      parent_i_pos_hi)/4)
> Since this expression does not result proper integer value, so will it
> be correct to directly put the value like
> +#define FAT_FID_SIZE_WITHOUT_PARENT 3

The issue is what I explained in the above "E.g.".

Directory traversal logic should be consolidate with fat_search_log().
Otherwise, like this nfs implement, we will introduce already-fixed-problem
again. And we will be bothered to fix same issue in future.
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>