Re: [PATCH 1/2] libxfs: zero the struct xfs_mount when unmounting the filesystem

Eric Sandeen
2020-02-25T18:48:09Z

On 2/25/20 10:28 AM, Darrick J. Wong wrote:
> On Tue, Feb 25, 2020 at 09:40:38AM -0800, Christoph Hellwig wrote:
>> On Mon, Feb 24, 2020 at 04:11:20PM -0800, Darrick J. Wong wrote:
>>> From: Darrick J. Wong <darrick.wong@oracle.com>
>>>
>>> Since libxfs doesn't allocate the struct xfs_mount *, we can't just free
>>> it during unmount. Zero its contents to prevent any use-after-free.
>>
>> I don't really this at all. Seems to be cargo-cult style programming.
>
> Admittedly I'm not convinced it's necessary either, seeing as we control
> all the callers, and none of them actually screw this up. But I defer
> to the maintainer. ;)

It struck me as odd as well, so despite my review I'll probably drop it,
given that there's no clear reason given to do this.

-Eric