Re: [PATCH] xfs: check for negatives in xfs_exchange_range_checks()

[Christoph Hellwig]

On Tue, May 07, 2024 at 09:33:40AM +0300, Dan Carpenter wrote:
> On Mon, May 06, 2024 at 11:06:17PM -0700, Christoph Hellwig wrote:
> > On Sat, May 04, 2024 at 02:27:36PM +0300, Dan Carpenter wrote:
> > > The fxr->file1_offset and fxr->file2_offset variables come from the user
> > > in xfs_ioc_exchange_range().  They are size loff_t which is an s64.
> > > Check the they aren't negative.
> > > 
> > > Fixes: 9a64d9b3109d ("xfs: introduce new file range exchange ioctl")
> > 
> > In this commit file1_offset and file2_offset are u64.  They used to
> > be u64 in the initial submission, but we changed that as part of the
> > review process.
> 
> I've just checked again, and I think it was loff_t in that commit.
> There are two related structs, the one that's userspace API and the
> one that's internal.  The userspace API is u64 but internally it's
> loff_t.

Ah, yes.  The in-kernel ones probably just needs to move to use u64
as well.