DPDK patches and discussions
 help / color / mirror / Atom feed
From: "Wiles, Keith" <keith.wiles@intel.com>
To: "Lipiec, Herakliusz" <herakliusz.lipiec@intel.com>
Cc: dpdk-dev <dev@dpdk.org>,
	"rasland@mellanox.com" <rasland@mellanox.com>,
	"stable@dpdk.org" <stable@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH v2] net/tap: fix potential buffer overrun
Date: Mon, 29 Apr 2019 13:58:57 +0000	[thread overview]
Message-ID: <7E00796C-D91F-47C4-B957-8561FC26F0E5@intel.com> (raw)
Message-ID: <20190429135857.4ZG_yjnxMnfYbVVhk4rXz7exEc9YjC0dpkV98Agaxso@z> (raw)
In-Reply-To: <20190425171702.933-1-herakliusz.lipiec@intel.com>



> On Apr 25, 2019, at 10:17 AM, Lipiec, Herakliusz <herakliusz.lipiec@intel.com> wrote:
> 
> When secondary to primary process synchronization occours
> there is no check for number of fds which could cause buffer overrun.
> 
> Bugzilla ID: 252
> Fixes: c9aa56edec8e ("net/tap: access primary process queues from secondary")
> Cc: rasland@mellanox.com
> Cc: stable@dpdk.org
> 
> Signed-off-by: Herakliusz Lipiec <herakliusz.lipiec@intel.com>
> ---
> drivers/net/tap/rte_eth_tap.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> index e9fda8cf6..4a2ef5ce7 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -2111,6 +2111,10 @@ tap_mp_attach_queues(const char *port_name, struct rte_eth_dev *dev)
> 	TAP_LOG(DEBUG, "Received IPC reply for %s", reply_param->port_name);
> 
> 	/* Attach the queues from received file descriptors */
> +	if (reply_param->rxq_count + reply_param->txq_count != reply->num_fds) {
> +		TAP_LOG(ERR, "Unexpected number of fds received");
> +		return -1;
> +	}

This check is reasonable, but why is this being done on the receive side and not checked on the send side. There may need to be a check for num_fds being zero or greater than 8 as that is the limit to the number of FDs that can be handle by the IPC.

In a different thread for Bug-258 we need to return an indicator that the receive side detected an error by returning 0 for num_fds and I have patch for that one.
https://bugs.dpdk.org/show_bug.cgi?id=258

I would have expected the sender to make sure they match and then this test is not needed, but a test for num_fds being zero or > 8 is needed if you want to detect the failure here or not if you do not care as long as nb_[r/t]x_queues is zero too.

> 	dev->data->nb_rx_queues = reply_param->rxq_count;
> 	dev->data->nb_tx_queues = reply_param->txq_count;
> 	fd_iterator = 0;
> @@ -2151,12 +2155,16 @@ tap_mp_sync_queues(const struct rte_mp_msg *request, const void *peer)
> 	/* Fill file descriptors for all queues */
> 	reply.num_fds = 0;
> 	reply_param->rxq_count = 0;
> +	if (dev->data->nb_rx_queues + dev->data->nb_tx_queues >
> +			RTE_MP_MAX_FD_NUM){
> +		TAP_LOG(ERR, "Number of rx/tx queues exceeds max number of fds");
> +		return -1;
> +	}
> 	for (queue = 0; queue < dev->data->nb_rx_queues; queue++) {
> 		reply.fds[reply.num_fds++] = process_private->rxq_fds[queue];
> 		reply_param->rxq_count++;
> 	}
> 	RTE_ASSERT(reply_param->rxq_count == dev->data->nb_rx_queues);
> -	RTE_ASSERT(reply_param->txq_count == dev->data->nb_tx_queues);
> 	RTE_ASSERT(reply.num_fds <= RTE_MP_MAX_FD_NUM);
> 
> 	reply_param->txq_count = 0;
> @@ -2164,7 +2172,8 @@ tap_mp_sync_queues(const struct rte_mp_msg *request, const void *peer)
> 		reply.fds[reply.num_fds++] = process_private->txq_fds[queue];
> 		reply_param->txq_count++;
> 	}
> -
> +	RTE_ASSERT(reply_param->txq_count == dev->data->nb_tx_queues);
> +	RTE_ASSERT(reply.num_fds <= RTE_MP_MAX_FD_NUM);
> 	/* Send reply */
> 	strlcpy(reply.name, request->name, sizeof(reply.name));
> 	strlcpy(reply_param->port_name, request_param->port_name,
> -- 
> 2.17.2
> 

Regards,
Keith


  parent reply	other threads:[~2019-04-29 13:59 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-25 16:47 [dpdk-dev] [PATCH] " Herakliusz Lipiec
2019-04-25 16:47 ` Herakliusz Lipiec
2019-04-25 17:17 ` [dpdk-dev] [PATCH v2] " Herakliusz Lipiec
2019-04-25 17:17   ` Herakliusz Lipiec
2019-04-29 13:32   ` Burakov, Anatoly
2019-04-29 13:32     ` Burakov, Anatoly
2019-04-29 13:53   ` Ferruh Yigit
2019-04-29 13:53     ` Ferruh Yigit
2019-04-29 14:02     ` Burakov, Anatoly
2019-04-29 14:02       ` Burakov, Anatoly
2019-04-30 10:42       ` Ferruh Yigit
2019-04-30 10:42         ` Ferruh Yigit
2019-04-29 13:58   ` Wiles, Keith [this message]
2019-04-29 13:58     ` Wiles, Keith
2019-04-29 14:05     ` Burakov, Anatoly
2019-04-29 14:05       ` Burakov, Anatoly
2019-04-29 17:31 ` [dpdk-dev] [PATCH v3] " Herakliusz Lipiec
2019-04-29 17:31   ` Herakliusz Lipiec
2019-05-02 16:31   ` [dpdk-dev] [dpdk-stable] " Ferruh Yigit
2019-05-02 16:31     ` Ferruh Yigit

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=7E00796C-D91F-47C4-B957-8561FC26F0E5@intel.com \
    --to=keith.wiles@intel.com \
    --cc=dev@dpdk.org \
    --cc=herakliusz.lipiec@intel.com \
    --cc=rasland@mellanox.com \
    --cc=stable@dpdk.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).