Re: [PATCH 10/11] fs: remove the access_ok() check in ioctl_fiemap

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Apr 28, 2020 at 08:21:24AM -0700, Darrick J. Wong wrote:
> On Mon, Apr 27, 2020 at 08:19:56PM +0200, Christoph Hellwig wrote:
> > access_ok just checks we are fed a proper user pointer.  We also do that
> > in copy_to_user itself, so no need to do this early.
> > 
> > Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> 
> Hmm.  It's a minor behavioral change that we no longer require the
> entire extent array to be accessible at the start even if parts of it
> would never have gotten accessed, but I don't think that matters, so:

Note that access_ok only checks if the memory actually is in userspace,
so they only thing seeing a behavior difference would be an exploit of
some kind.



[Index of Archives]     [Reiser Filesystem Development]     [Ceph FS]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux FS]     [Yosemite National Park]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]     [Linux Media]

  Powered by Linux