From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762924AbZLPTGL (ORCPT ); Wed, 16 Dec 2009 14:06:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964861AbZLPTF4 (ORCPT ); Wed, 16 Dec 2009 14:05:56 -0500 Received: from ey-out-2122.google.com ([74.125.78.24]:51937 "EHLO ey-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964873AbZLPTFy convert rfc822-to-8bit (ORCPT ); Wed, 16 Dec 2009 14:05:54 -0500 MIME-Version: 1.0 In-Reply-To: <20091216182433.GA28134@ioremap.net> References: <1260716147-1569-1-git-send-email-a.beregalov@gmail.com> <20091216182433.GA28134@ioremap.net> Date: Wed, 16 Dec 2009 22:05:52 +0300 Message-ID: Subject: Re: [PATCH] Staging: dst: fix 'Client is not allowed' on sparc From: Alexander Beregalov To: Evgeniy Polyakov Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, sparclinux@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2009/12/16 Evgeniy Polyakov : > Hi Alexander. > > Sorry for late response. > Your patch looks good, I will forward it to GregKH for inclusion. But how does inet_getname() set sa_data_len to 0. I can't imagine. My patch is a workaround, not a fix. Btw, it does not work on sparc anyway, it needs further digging. > Thank you. > > On Sun, Dec 13, 2009 at 05:55:47PM +0300, Alexander Beregalov (a.beregalov@gmail.com) wrote: >> >> Not for applying, only describe the problem. >> >> >> There is a warning on sparc >>  Kernel unaligned access at TPC[6c0dec] inet_getname+0x4c/0xc0 >> which goes from >>       net/ipv4/af_inet.c: >>       int inet_getname( >>               ... >>               *uaddr_len = sizeof(*sin); >> >> sizeof(*sin) is 16, but inet_getname sets sa_data_len to 0. >> That is why client is denied to access the device. >> inet_getname() does not read uaddr_len, only >> writes, so move initialization of sa_data_len after it. >> Make struct saddr aligned similar to >> struct __kernel_sockaddr_storage. This fixes the warning. >> >> --- >>  drivers/staging/dst/export.c |    2 +- >>  include/linux/dst.h          |    4 ++-- >>  2 files changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/staging/dst/export.c b/drivers/staging/dst/export.c >> index c324230..4644804 100644 >> --- a/drivers/staging/dst/export.c >> +++ b/drivers/staging/dst/export.c >> @@ -166,12 +166,12 @@ static struct dst_state *dst_accept_client(struct dst_state *st) >>       } >>       new->socket = sock; >> >> -     new->ctl.addr.sa_data_len = sizeof(struct sockaddr); >>       err = kernel_getpeername(sock, (struct sockaddr *)&new->ctl.addr, >>                       (int *)&new->ctl.addr.sa_data_len); >>       if (err) >>               goto err_out_put; >> >> +     new->ctl.addr.sa_data_len = sizeof(struct sockaddr); >>       new->permissions = dst_check_permissions(st, new); >>       if (new->permissions == 0) { >>               err = -EPERM; >> diff --git a/include/linux/dst.h b/include/linux/dst.h >> index e26fed8..454b15a 100644 >> --- a/include/linux/dst.h >> +++ b/include/linux/dst.h >> @@ -74,10 +74,10 @@ struct saddr { >>       /* address family, AF_xxx       */ >>       unsigned short          sa_family; >>       /* 14 bytes of protocol address */ >> -     char                    sa_data[SADDR_MAX_DATA]; >> +     char                    sa_data[SADDR_MAX_DATA - sizeof(unsigned short)]; >>       /* Number of bytes used in sa_data */ >>       unsigned short          sa_data_len; >> -}; >> +} __attribute__((aligned(16)));      /* sizeof(struct sockaddr) */ >> >>  /* Address structure */ >>  struct dst_network_ctl >> -- >> 1.6.5.6 > > -- >        Evgeniy Polyakov >