From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E16B6C43381 for ; Tue, 19 Mar 2019 16:15:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A5CC120854 for ; Tue, 19 Mar 2019 16:15:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="qxq7DiID" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727713AbfCSQPA (ORCPT ); Tue, 19 Mar 2019 12:15:00 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:43311 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726579AbfCSQO7 (ORCPT ); Tue, 19 Mar 2019 12:14:59 -0400 Received: by mail-pf1-f195.google.com with SMTP id c8so7389628pfd.10 for ; Tue, 19 Mar 2019 09:14:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=PQgiC0kZ9u3Fy9QCp4MSDtSraYleFQhb/2xaBu2ZSrg=; b=qxq7DiIDvuLMVQ34GJzbbwphhe3KaybKNLLIgWZcGxMMwPerSCP8RL7QKUW6OtyBKf 93s0/L1vzqFcVzh/gw7Cxoq5tPb1/WaJXpXJp3yNxXHHX+7WMTlqOagmGKRDtUxEMSKg 5DS0enSD5PzEjo4jy+UcwIsjiJOFl6BnvOboDUvPFYRjHX6Bkquppw7J1+eqRrui0XyJ 5KwS2/Yj9IcZSKFd33h7Wg5DbPnCVWpSh5pGJ75s8D7bMH8YcmfdqR842AAg13swxCOv Kk2MxlHMbY3GoTWt8xmPsHQ5oVfatT1NEXrOp0w5gHtoFSTLFLhBqpyqHShIAnZJ8YpW APtQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=PQgiC0kZ9u3Fy9QCp4MSDtSraYleFQhb/2xaBu2ZSrg=; b=TirQHLZap167mZWI0b+mQRpvmbEBF1OVz09+6yKTztvMMuGbBMEszKXQgS378JLoQj stt7T6nCirBDXnRSq25tBTB1EjWP118SkwxkK6eu91RXd/ItX75omaE0tXTgMKJ+hiqt tcig86GIlFqbBz/aeWinJ0MDoCYMqTeXT8m1Jc9sWqB0TB5OahFoW9eWxWhjgpvtUbMH gEc5+CMBMobJ0g69E8dSWjOj+hqbNR3C4nZfS1wK4DBuAJ5cf3/WTcfJqZ2dd+mLGrG1 cfoddJTyMneXtnblmErBlR4lNFmmh4m9vLvBW12IFwMsfKlgPXXCCzv2k8T2mzX8/X+w Cnzw== X-Gm-Message-State: APjAAAVkH7F/T1OupxGLxocVsraAUbng+MfKhJPceJsLkkoAnF9JY4QJ 2FLap7ZPJfcose+ZT69hYVOZGNVFh+5yohqGV2u0Sg== X-Google-Smtp-Source: APXvYqx361ALMb6OFk9w1BYTE4ilOTi6pgHPRxfVkFU9fEbW6rIBYMGJVoPW0XyRhBBEcWy7HAhjNpDB7rRiY+mc1bo= X-Received: by 2002:aa7:8b12:: with SMTP id f18mr3253945pfd.240.1553012098901; Tue, 19 Mar 2019 09:14:58 -0700 (PDT) MIME-Version: 1.0 References: <80e79c47dc7c5ee3572034a1d69bb724fbed2ecb.1552929301.git.andreyknvl@google.com> In-Reply-To: From: Andrey Konovalov Date: Tue, 19 Mar 2019 17:14:47 +0100 Message-ID: Subject: Re: [PATCH v12 08/13] net, arm64: untag user pointers in tcp_zerocopy_receive To: Eric Dumazet Cc: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Linux ARM , "open list:DOCUMENTATION" , linux-mm , linux-arch , netdev , bpf , "open list:KERNEL SELFTEST FRAMEWORK" , LKML , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 18, 2019 at 6:35 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 10:18 AM Andrey Konovalov wrote: > > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > tcp_zerocopy_receive() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > net/ipv4/tcp.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > > index 6baa6dc1b13b..e76beb5ff1ff 100644 > > --- a/net/ipv4/tcp.c > > +++ b/net/ipv4/tcp.c > > @@ -1749,7 +1749,7 @@ EXPORT_SYMBOL(tcp_mmap); > > static int tcp_zerocopy_receive(struct sock *sk, > > struct tcp_zerocopy_receive *zc) > > { > > - unsigned long address = (unsigned long)zc->address; > > + unsigned long address; > > const skb_frag_t *frags = NULL; > > u32 length = 0, seq, offset; > > struct vm_area_struct *vma; > > @@ -1758,7 +1758,12 @@ static int tcp_zerocopy_receive(struct sock *sk, > > int inq; > > int ret; > > > > - if (address & (PAGE_SIZE - 1) || address != zc->address) > > + address = (unsigned long)untagged_addr(zc->address); > > + > > + /* The second test in this if detects if the u64->unsigned long > > + * conversion had any truncated bits. > > + */ > > + if (address & (PAGE_SIZE - 1) || address != untagged_addr(zc->address)) > > return -EINVAL; > > > > if (sk->sk_state == TCP_LISTEN) > > > This is quite ugly, the comment does not really help nor belong to this patch. > > What about using untagged_addr() only once ? > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index 6baa6dc1b13b0b94b1da238668b93e167cf444fe..855a1f68c1ea9b0d07a92bd7f5e7c24840a99d3d > 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -1761,6 +1761,8 @@ static int tcp_zerocopy_receive(struct sock *sk, > if (address & (PAGE_SIZE - 1) || address != zc->address) > return -EINVAL; > > + address = untagged_addr(address); > + > if (sk->sk_state == TCP_LISTEN) > return -ENOTCONN; Looks good, will do it like this in the next version. Thanks! From mboxrd@z Thu Jan 1 00:00:00 1970 From: andreyknvl at google.com (Andrey Konovalov) Date: Tue, 19 Mar 2019 17:14:47 +0100 Subject: [PATCH v12 08/13] net, arm64: untag user pointers in tcp_zerocopy_receive In-Reply-To: References: <80e79c47dc7c5ee3572034a1d69bb724fbed2ecb.1552929301.git.andreyknvl@google.com> Message-ID: On Mon, Mar 18, 2019 at 6:35 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 10:18 AM Andrey Konovalov wrote: > > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > tcp_zerocopy_receive() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > net/ipv4/tcp.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > > index 6baa6dc1b13b..e76beb5ff1ff 100644 > > --- a/net/ipv4/tcp.c > > +++ b/net/ipv4/tcp.c > > @@ -1749,7 +1749,7 @@ EXPORT_SYMBOL(tcp_mmap); > > static int tcp_zerocopy_receive(struct sock *sk, > > struct tcp_zerocopy_receive *zc) > > { > > - unsigned long address = (unsigned long)zc->address; > > + unsigned long address; > > const skb_frag_t *frags = NULL; > > u32 length = 0, seq, offset; > > struct vm_area_struct *vma; > > @@ -1758,7 +1758,12 @@ static int tcp_zerocopy_receive(struct sock *sk, > > int inq; > > int ret; > > > > - if (address & (PAGE_SIZE - 1) || address != zc->address) > > + address = (unsigned long)untagged_addr(zc->address); > > + > > + /* The second test in this if detects if the u64->unsigned long > > + * conversion had any truncated bits. > > + */ > > + if (address & (PAGE_SIZE - 1) || address != untagged_addr(zc->address)) > > return -EINVAL; > > > > if (sk->sk_state == TCP_LISTEN) > > > This is quite ugly, the comment does not really help nor belong to this patch. > > What about using untagged_addr() only once ? > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index 6baa6dc1b13b0b94b1da238668b93e167cf444fe..855a1f68c1ea9b0d07a92bd7f5e7c24840a99d3d > 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -1761,6 +1761,8 @@ static int tcp_zerocopy_receive(struct sock *sk, > if (address & (PAGE_SIZE - 1) || address != zc->address) > return -EINVAL; > > + address = untagged_addr(address); > + > if (sk->sk_state == TCP_LISTEN) > return -ENOTCONN; Looks good, will do it like this in the next version. Thanks! From mboxrd@z Thu Jan 1 00:00:00 1970 From: andreyknvl@google.com (Andrey Konovalov) Date: Tue, 19 Mar 2019 17:14:47 +0100 Subject: [PATCH v12 08/13] net, arm64: untag user pointers in tcp_zerocopy_receive In-Reply-To: References: <80e79c47dc7c5ee3572034a1d69bb724fbed2ecb.1552929301.git.andreyknvl@google.com> Message-ID: Content-Type: text/plain; charset="UTF-8" Message-ID: <20190319161447.Q9EAZN04RQoXW5eYCLUc6lFZ2W20q45HEI56F6RGOHs@z> On Mon, Mar 18, 2019@6:35 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019@10:18 AM Andrey Konovalov wrote: > > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > tcp_zerocopy_receive() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > net/ipv4/tcp.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > > index 6baa6dc1b13b..e76beb5ff1ff 100644 > > --- a/net/ipv4/tcp.c > > +++ b/net/ipv4/tcp.c > > @@ -1749,7 +1749,7 @@ EXPORT_SYMBOL(tcp_mmap); > > static int tcp_zerocopy_receive(struct sock *sk, > > struct tcp_zerocopy_receive *zc) > > { > > - unsigned long address = (unsigned long)zc->address; > > + unsigned long address; > > const skb_frag_t *frags = NULL; > > u32 length = 0, seq, offset; > > struct vm_area_struct *vma; > > @@ -1758,7 +1758,12 @@ static int tcp_zerocopy_receive(struct sock *sk, > > int inq; > > int ret; > > > > - if (address & (PAGE_SIZE - 1) || address != zc->address) > > + address = (unsigned long)untagged_addr(zc->address); > > + > > + /* The second test in this if detects if the u64->unsigned long > > + * conversion had any truncated bits. > > + */ > > + if (address & (PAGE_SIZE - 1) || address != untagged_addr(zc->address)) > > return -EINVAL; > > > > if (sk->sk_state == TCP_LISTEN) > > > This is quite ugly, the comment does not really help nor belong to this patch. > > What about using untagged_addr() only once ? > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index 6baa6dc1b13b0b94b1da238668b93e167cf444fe..855a1f68c1ea9b0d07a92bd7f5e7c24840a99d3d > 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -1761,6 +1761,8 @@ static int tcp_zerocopy_receive(struct sock *sk, > if (address & (PAGE_SIZE - 1) || address != zc->address) > return -EINVAL; > > + address = untagged_addr(address); > + > if (sk->sk_state == TCP_LISTEN) > return -ENOTCONN; Looks good, will do it like this in the next version. Thanks! From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Konovalov Subject: Re: [PATCH v12 08/13] net, arm64: untag user pointers in tcp_zerocopy_receive Date: Tue, 19 Mar 2019 17:14:47 +0100 Message-ID: References: <80e79c47dc7c5ee3572034a1d69bb724fbed2ecb.1552929301.git.andreyknvl@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Eric Dumazet Cc: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo List-Id: linux-arch.vger.kernel.org On Mon, Mar 18, 2019 at 6:35 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 10:18 AM Andrey Konovalov wrote: > > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > tcp_zerocopy_receive() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > net/ipv4/tcp.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > > index 6baa6dc1b13b..e76beb5ff1ff 100644 > > --- a/net/ipv4/tcp.c > > +++ b/net/ipv4/tcp.c > > @@ -1749,7 +1749,7 @@ EXPORT_SYMBOL(tcp_mmap); > > static int tcp_zerocopy_receive(struct sock *sk, > > struct tcp_zerocopy_receive *zc) > > { > > - unsigned long address = (unsigned long)zc->address; > > + unsigned long address; > > const skb_frag_t *frags = NULL; > > u32 length = 0, seq, offset; > > struct vm_area_struct *vma; > > @@ -1758,7 +1758,12 @@ static int tcp_zerocopy_receive(struct sock *sk, > > int inq; > > int ret; > > > > - if (address & (PAGE_SIZE - 1) || address != zc->address) > > + address = (unsigned long)untagged_addr(zc->address); > > + > > + /* The second test in this if detects if the u64->unsigned long > > + * conversion had any truncated bits. > > + */ > > + if (address & (PAGE_SIZE - 1) || address != untagged_addr(zc->address)) > > return -EINVAL; > > > > if (sk->sk_state == TCP_LISTEN) > > > This is quite ugly, the comment does not really help nor belong to this patch. > > What about using untagged_addr() only once ? > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index 6baa6dc1b13b0b94b1da238668b93e167cf444fe..855a1f68c1ea9b0d07a92bd7f5e7c24840a99d3d > 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -1761,6 +1761,8 @@ static int tcp_zerocopy_receive(struct sock *sk, > if (address & (PAGE_SIZE - 1) || address != zc->address) > return -EINVAL; > > + address = untagged_addr(address); > + > if (sk->sk_state == TCP_LISTEN) > return -ENOTCONN; Looks good, will do it like this in the next version. Thanks! From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f196.google.com ([209.85.210.196]:46162 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727443AbfCSQPA (ORCPT ); Tue, 19 Mar 2019 12:15:00 -0400 Received: by mail-pf1-f196.google.com with SMTP id s23so14020774pfe.13 for ; Tue, 19 Mar 2019 09:14:59 -0700 (PDT) MIME-Version: 1.0 References: <80e79c47dc7c5ee3572034a1d69bb724fbed2ecb.1552929301.git.andreyknvl@google.com> In-Reply-To: From: Andrey Konovalov Date: Tue, 19 Mar 2019 17:14:47 +0100 Message-ID: Subject: Re: [PATCH v12 08/13] net, arm64: untag user pointers in tcp_zerocopy_receive Content-Type: text/plain; charset="UTF-8" Sender: linux-arch-owner@vger.kernel.org List-ID: To: Eric Dumazet Cc: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Linux ARM , "open list:DOCUMENTATION" , linux-mm , linux-arch , netdev , bpf , "open list:KERNEL SELFTEST FRAMEWORK" , LKML , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy Message-ID: <20190319161447.YexKX7y0Q3qAnIr12755gR0wydQpUeGmhh7dSswEj8Q@z> On Mon, Mar 18, 2019 at 6:35 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 10:18 AM Andrey Konovalov wrote: > > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > tcp_zerocopy_receive() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > net/ipv4/tcp.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > > index 6baa6dc1b13b..e76beb5ff1ff 100644 > > --- a/net/ipv4/tcp.c > > +++ b/net/ipv4/tcp.c > > @@ -1749,7 +1749,7 @@ EXPORT_SYMBOL(tcp_mmap); > > static int tcp_zerocopy_receive(struct sock *sk, > > struct tcp_zerocopy_receive *zc) > > { > > - unsigned long address = (unsigned long)zc->address; > > + unsigned long address; > > const skb_frag_t *frags = NULL; > > u32 length = 0, seq, offset; > > struct vm_area_struct *vma; > > @@ -1758,7 +1758,12 @@ static int tcp_zerocopy_receive(struct sock *sk, > > int inq; > > int ret; > > > > - if (address & (PAGE_SIZE - 1) || address != zc->address) > > + address = (unsigned long)untagged_addr(zc->address); > > + > > + /* The second test in this if detects if the u64->unsigned long > > + * conversion had any truncated bits. > > + */ > > + if (address & (PAGE_SIZE - 1) || address != untagged_addr(zc->address)) > > return -EINVAL; > > > > if (sk->sk_state == TCP_LISTEN) > > > This is quite ugly, the comment does not really help nor belong to this patch. > > What about using untagged_addr() only once ? > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index 6baa6dc1b13b0b94b1da238668b93e167cf444fe..855a1f68c1ea9b0d07a92bd7f5e7c24840a99d3d > 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -1761,6 +1761,8 @@ static int tcp_zerocopy_receive(struct sock *sk, > if (address & (PAGE_SIZE - 1) || address != zc->address) > return -EINVAL; > > + address = untagged_addr(address); > + > if (sk->sk_state == TCP_LISTEN) > return -ENOTCONN; Looks good, will do it like this in the next version. Thanks! 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[209.85.220.65]) by mx.google.com with SMTPS id l75sor20555171pfj.31.2019.03.19.09.14.59 for (Google Transport Security); Tue, 19 Mar 2019 09:14:59 -0700 (PDT) Received-SPF: pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=qxq7DiID; spf=pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=andreyknvl@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=PQgiC0kZ9u3Fy9QCp4MSDtSraYleFQhb/2xaBu2ZSrg=; b=qxq7DiIDvuLMVQ34GJzbbwphhe3KaybKNLLIgWZcGxMMwPerSCP8RL7QKUW6OtyBKf 93s0/L1vzqFcVzh/gw7Cxoq5tPb1/WaJXpXJp3yNxXHHX+7WMTlqOagmGKRDtUxEMSKg 5DS0enSD5PzEjo4jy+UcwIsjiJOFl6BnvOboDUvPFYRjHX6Bkquppw7J1+eqRrui0XyJ 5KwS2/Yj9IcZSKFd33h7Wg5DbPnCVWpSh5pGJ75s8D7bMH8YcmfdqR842AAg13swxCOv Kk2MxlHMbY3GoTWt8xmPsHQ5oVfatT1NEXrOp0w5gHtoFSTLFLhBqpyqHShIAnZJ8YpW APtQ== X-Google-Smtp-Source: APXvYqx361ALMb6OFk9w1BYTE4ilOTi6pgHPRxfVkFU9fEbW6rIBYMGJVoPW0XyRhBBEcWy7HAhjNpDB7rRiY+mc1bo= X-Received: by 2002:aa7:8b12:: with SMTP id f18mr3253945pfd.240.1553012098901; Tue, 19 Mar 2019 09:14:58 -0700 (PDT) MIME-Version: 1.0 References: <80e79c47dc7c5ee3572034a1d69bb724fbed2ecb.1552929301.git.andreyknvl@google.com> In-Reply-To: From: Andrey Konovalov Date: Tue, 19 Mar 2019 17:14:47 +0100 Message-ID: Subject: Re: [PATCH v12 08/13] net, arm64: untag user pointers in tcp_zerocopy_receive To: Eric Dumazet Cc: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Linux ARM , "open list:DOCUMENTATION" , linux-mm , linux-arch , netdev , bpf , "open list:KERNEL SELFTEST FRAMEWORK" , LKML , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Mar 18, 2019 at 6:35 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 10:18 AM Andrey Konovalov wrote: > > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > tcp_zerocopy_receive() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > net/ipv4/tcp.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > > index 6baa6dc1b13b..e76beb5ff1ff 100644 > > --- a/net/ipv4/tcp.c > > +++ b/net/ipv4/tcp.c > > @@ -1749,7 +1749,7 @@ EXPORT_SYMBOL(tcp_mmap); > > static int tcp_zerocopy_receive(struct sock *sk, > > struct tcp_zerocopy_receive *zc) > > { > > - unsigned long address = (unsigned long)zc->address; > > + unsigned long address; > > const skb_frag_t *frags = NULL; > > u32 length = 0, seq, offset; > > struct vm_area_struct *vma; > > @@ -1758,7 +1758,12 @@ static int tcp_zerocopy_receive(struct sock *sk, > > int inq; > > int ret; > > > > - if (address & (PAGE_SIZE - 1) || address != zc->address) > > + address = (unsigned long)untagged_addr(zc->address); > > + > > + /* The second test in this if detects if the u64->unsigned long > > + * conversion had any truncated bits. > > + */ > > + if (address & (PAGE_SIZE - 1) || address != untagged_addr(zc->address)) > > return -EINVAL; > > > > if (sk->sk_state == TCP_LISTEN) > > > This is quite ugly, the comment does not really help nor belong to this patch. > > What about using untagged_addr() only once ? > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index 6baa6dc1b13b0b94b1da238668b93e167cf444fe..855a1f68c1ea9b0d07a92bd7f5e7c24840a99d3d > 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -1761,6 +1761,8 @@ static int tcp_zerocopy_receive(struct sock *sk, > if (address & (PAGE_SIZE - 1) || address != zc->address) > return -EINVAL; > > + address = untagged_addr(address); > + > if (sk->sk_state == TCP_LISTEN) > return -ENOTCONN; Looks good, will do it like this in the next version. Thanks! 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a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=PQgiC0kZ9u3Fy9QCp4MSDtSraYleFQhb/2xaBu2ZSrg=; b=pfdmXi+zIXv9yfErlJONCCLHln+VdHVSp7NL546KhSz5uhINScvx73cNjT0o4adfFM iHIyB+ELLzgExw9GuIoBCejdF6oITVVE/pRYPTAMRNms5IWs4LKM3j5QZlgCZpYd38DB h482yZCko2ydJxdoEoR9JiJNh1CXDRpz8C8mYtDRjdz59fvInPtp9dUYHjf2/Saj7ZLI SXZ/6uNunyYrpUBGOxJJZ+wuK2ykHRwsBsoTFUJgUVRIrdnyuos8QJe2zdFQgtKM8/uv rEXcwqcsP0pw7mkR5vqR3JjHuGdz4SThS8NQUE9ME326KyRQhSlFCyeTF9QUpekRjuID +etQ== X-Gm-Message-State: APjAAAXk+wM7gUZMTDrzIXtsbiYzo1RtswnAMSBmL3ztoE1P4h7xYtYo 6ey+aHP1alQVxZqghfB6RET62rzq5FY1Y+pvluO+WQ== X-Google-Smtp-Source: APXvYqx361ALMb6OFk9w1BYTE4ilOTi6pgHPRxfVkFU9fEbW6rIBYMGJVoPW0XyRhBBEcWy7HAhjNpDB7rRiY+mc1bo= X-Received: by 2002:aa7:8b12:: with SMTP id f18mr3253945pfd.240.1553012098901; Tue, 19 Mar 2019 09:14:58 -0700 (PDT) MIME-Version: 1.0 References: <80e79c47dc7c5ee3572034a1d69bb724fbed2ecb.1552929301.git.andreyknvl@google.com> In-Reply-To: From: Andrey Konovalov Date: Tue, 19 Mar 2019 17:14:47 +0100 Message-ID: Subject: Re: [PATCH v12 08/13] net, arm64: untag user pointers in tcp_zerocopy_receive To: Eric Dumazet X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190319_091502_354138_431A68F1 X-CRM114-Status: GOOD ( 23.51 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kate Stewart , "open list:DOCUMENTATION" , Peter Zijlstra , Catalin Marinas , Will Deacon , Alexei Starovoitov , linux-mm , "open list:KERNEL SELFTEST FRAMEWORK" , Chintan Pandya , Vincenzo Frascino , Shuah Khan , Ingo Molnar , linux-arch , Jacob Bramley , Daniel Borkmann , Szabolcs Nagy , Ingo Molnar , Dmitry Vyukov , Ramana Radhakrishnan , Dave Martin , Evgeniy Stepanov , Kevin Brodsky , Kees Cook , Ruben Ayrapetyan , Lee Smith , Steven Rostedt , Arnaldo Carvalho de Melo , bpf , Linux ARM , Kostya Serebryany , Greg Kroah-Hartman , LKML , Luc Van Oostenryck , netdev , Andrew Morton , Robin Murphy , "David S. Miller" , "Kirill A . Shutemov" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Mar 18, 2019 at 6:35 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 10:18 AM Andrey Konovalov wrote: > > > > This patch is a part of a series that extends arm64 kernel ABI to allow to > > pass tagged user pointers (with the top byte set to something else other > > than 0x00) as syscall arguments. > > > > tcp_zerocopy_receive() uses provided user pointers for vma lookups, which > > can only by done with untagged pointers. > > > > Untag user pointers in this function. > > > > Signed-off-by: Andrey Konovalov > > --- > > net/ipv4/tcp.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > > index 6baa6dc1b13b..e76beb5ff1ff 100644 > > --- a/net/ipv4/tcp.c > > +++ b/net/ipv4/tcp.c > > @@ -1749,7 +1749,7 @@ EXPORT_SYMBOL(tcp_mmap); > > static int tcp_zerocopy_receive(struct sock *sk, > > struct tcp_zerocopy_receive *zc) > > { > > - unsigned long address = (unsigned long)zc->address; > > + unsigned long address; > > const skb_frag_t *frags = NULL; > > u32 length = 0, seq, offset; > > struct vm_area_struct *vma; > > @@ -1758,7 +1758,12 @@ static int tcp_zerocopy_receive(struct sock *sk, > > int inq; > > int ret; > > > > - if (address & (PAGE_SIZE - 1) || address != zc->address) > > + address = (unsigned long)untagged_addr(zc->address); > > + > > + /* The second test in this if detects if the u64->unsigned long > > + * conversion had any truncated bits. > > + */ > > + if (address & (PAGE_SIZE - 1) || address != untagged_addr(zc->address)) > > return -EINVAL; > > > > if (sk->sk_state == TCP_LISTEN) > > > This is quite ugly, the comment does not really help nor belong to this patch. > > What about using untagged_addr() only once ? > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index 6baa6dc1b13b0b94b1da238668b93e167cf444fe..855a1f68c1ea9b0d07a92bd7f5e7c24840a99d3d > 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -1761,6 +1761,8 @@ static int tcp_zerocopy_receive(struct sock *sk, > if (address & (PAGE_SIZE - 1) || address != zc->address) > return -EINVAL; > > + address = untagged_addr(address); > + > if (sk->sk_state == TCP_LISTEN) > return -ENOTCONN; Looks good, will do it like this in the next version. Thanks! _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel