From: Juergen Gross <jgross@suse.com>
To: Jan Beulich <jbeulich@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>,
Stefano Stabellini <sstabellini@kernel.org>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
xen-devel@lists.xenproject.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 5/8] xen/netfront: read response from backend only once
Date: Mon, 17 May 2021 16:24:45 +0200 [thread overview]
Message-ID: <132c33ae-52c9-532b-b0b4-b5952db09720@suse.com> (raw)
In-Reply-To: <c9f90370-fc02-3f05-0670-35f795c59d95@suse.com>
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On 17.05.21 16:20, Jan Beulich wrote:
> On 13.05.2021 12:02, Juergen Gross wrote:
>> In order to avoid problems in case the backend is modifying a response
>> on the ring page while the frontend has already seen it, just read the
>> response into a local buffer in one go and then operate on that buffer
>> only.
>>
>> Signed-off-by: Juergen Gross <jgross@suse.com>
>
> Reviewed-by: Jan Beulich <jbeulich@suse.com>
> with one remark:
>
>> @@ -830,24 +830,22 @@ static int xennet_get_extras(struct netfront_queue *queue,
>> break;
>> }
>>
>> - extra = (struct xen_netif_extra_info *)
>> - RING_GET_RESPONSE(&queue->rx, ++cons);
>> + RING_COPY_RESPONSE(&queue->rx, ++cons, &extra);
>>
>> - if (unlikely(!extra->type ||
>> - extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
>> + if (unlikely(!extra.type ||
>> + extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
>> if (net_ratelimit())
>> dev_warn(dev, "Invalid extra type: %d\n",
>> - extra->type);
>> + extra.type);
>> err = -EINVAL;
>> } else {
>> - memcpy(&extras[extra->type - 1], extra,
>> - sizeof(*extra));
>> + memcpy(&extras[extra.type - 1], &extra, sizeof(extra));
>
> Maybe take the opportunity and switch to (type safe) structure
> assignment?
Yes, good idea.
Juergen
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next prev parent reply other threads:[~2021-05-17 14:24 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-13 10:02 [PATCH 0/8] xen: harden frontends against malicious backends Juergen Gross
2021-05-13 10:02 ` [PATCH 1/8] xen: sync include/xen/interface/io/ring.h with Xen's newest version Juergen Gross
2021-05-13 10:02 ` [PATCH 2/8] xen/blkfront: read response from backend only once Juergen Gross
2021-05-17 13:50 ` Jan Beulich
2021-05-13 10:02 ` [PATCH 3/8] xen/blkfront: don't take local copy of a request from the ring page Juergen Gross
2021-05-17 14:01 ` Jan Beulich
2021-05-17 14:11 ` Juergen Gross
2021-05-13 10:02 ` [PATCH 4/8] xen/blkfront: don't trust the backend response data blindly Juergen Gross
2021-05-17 14:11 ` Jan Beulich
2021-05-17 14:23 ` Juergen Gross
2021-05-17 15:12 ` Jan Beulich
2021-05-17 15:22 ` Juergen Gross
2021-05-17 15:33 ` Jan Beulich
2021-07-08 5:47 ` Juergen Gross
2021-07-08 6:37 ` Jan Beulich
2021-07-08 6:40 ` Juergen Gross
2021-07-08 6:52 ` Jan Beulich
2021-07-08 6:56 ` Juergen Gross
2021-05-13 10:02 ` [PATCH 5/8] xen/netfront: read response from backend only once Juergen Gross
2021-05-17 14:20 ` Jan Beulich
2021-05-17 14:24 ` Juergen Gross [this message]
2021-05-13 10:03 ` [PATCH 6/8] xen/netfront: don't read data from request on the ring page Juergen Gross
2021-05-17 15:08 ` Jan Beulich
2021-05-13 10:03 ` [PATCH 7/8] xen/netfront: don't trust the backend response data blindly Juergen Gross
2021-05-17 15:31 ` Jan Beulich
2021-05-13 10:03 ` [PATCH 8/8] xen/hvc: replace BUG_ON() with negative return value Juergen Gross
2021-05-13 10:16 ` Christophe Leroy
2021-05-13 10:20 ` Juergen Gross
2021-05-13 10:25 ` Greg Kroah-Hartman
2021-05-13 10:35 ` Juergen Gross
2021-05-21 10:43 ` [PATCH 0/8] xen: harden frontends against malicious backends Marek Marczykowski-Górecki
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