Re: [PATCH bpf v1] unix: fix an issue in unix_shutdown causing the other end read/write failures

[Jakub Kicinski]

On Fri, 19 Nov 2021 06:14:19 -0800 Jakub Kicinski wrote:
> On Thu, 11 Nov 2021 15:00:02 +0100 Vincent Whitchurch wrote:
> > On Mon, Oct 04, 2021 at 11:25:28PM +0000, Jiang Wang wrote:  
> > > Commit 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap")
> > > sets unix domain socket peer state to TCP_CLOSE
> > > in unix_shutdown. This could happen when the local end is shutdown
> > > but the other end is not. Then the other end will get read or write
> > > failures which is not expected.
> > > 
> > > Fix the issue by setting the local state to shutdown.
> > > 
> > > Fixes: 94531cfcbe79 (af_unix: Add unix_stream_proto for sockmap)
> > > Suggested-by: Cong Wang <cong.wang@xxxxxxxxxxxxx>
> > > Reported-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
> > > Signed-off-by: Jiang Wang <jiang.wang@xxxxxxxxxxxxx>    
> > 
> > This patch changed the behaviour of read(2) after a shutdown(2) on the
> > local end of a UDS.  Before this patch, reading from a UDS after a local
> > shutdown(SHUT_RDWR) would return the data written or EOF if there is no
> > data, but now it always returns -EINVAL.
> > 
> > For example, the following test program succeeds with "read 16 bytes" on
> > v5.14 but fails with "read: Invalid argument" on v5.15 and mainline:  
> 
> Cong, Jiang, was this regression addressed?

Ah, just saw the patch. What timing.

Thanks Vincent!