From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Biggers Date: Mon, 20 Jul 2020 16:38:36 +0000 Subject: Re: get rid of the address_space override in setsockopt Message-Id: <20200720163836.GB1292162@gmail.com> List-Id: References: <20200720124737.118617-1-hch@lst.de> In-Reply-To: <20200720124737.118617-1-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: dccp@vger.kernel.org On Mon, Jul 20, 2020 at 02:47:13PM +0200, Christoph Hellwig wrote: > Hi Dave, > > setsockopt is the last place in architecture-independ code that still > uses set_fs to force the uaccess routines to operate on kernel pointers. > > This series adds a new sockptr_t type that can contained either a kernel > or user pointer, and which has accessors that do the right thing, and > then uses it for setsockopt, starting by refactoring some low-level > helpers and moving them over to it before finally doing the main > setsockopt method. > > Note that I could not get the eBPF selftests to work, so this has been > tested with a testing patch that always copies the data first and passes > a kernel pointer. This is something that works for most common sockopts > (and is something that the ePBF support relies on), but unfortunately > in various corner cases we either don't use the passed in length, or in > one case actually copy data back from setsockopt, so we unfortunately > can't just always do the copy in the highlevel code, which would have > been much nicer. > Please mention what git tree your patchset applies to. - Eric