linux-kernel - Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <fdf6ab76-cd2c-6596-41c1-369c176decad@wanadoo.fr>
Date:   Mon, 29 May 2023 16:25:09 +0200
From:   Christophe JAILLET <christophe.jaillet@...adoo.fr>
To:     Shradha Gupta <shradhagupta@...ux.microsoft.com>
Cc:     linux-kernel@...r.kernel.org, linux-hyperv@...r.kernel.org,
        netdev@...r.kernel.org, Eric Dumazet <edumazet@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        "K. Y. Srinivasan" <kys@...rosoft.com>,
        Haiyang Zhang <haiyangz@...rosoft.com>,
        Wei Liu <wei.liu@...nel.org>, Dexuan Cui <decui@...rosoft.com>,
        Long Li <longli@...rosoft.com>,
        Michael Kelley <mikelley@...rosoft.com>,
        "David S. Miller" <davem@...emloft.net>,
        Steen Hegelund <steen.hegelund@...rochip.com>,
        Simon Horman <simon.horman@...igine.com>
Subject: Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size
 dynamically

Le 29/05/2023 à 15:30, Shradha Gupta a écrit :
> Thanks for the comment Christophe.
> On Mon, May 29, 2023 at 02:49:15PM +0200, Christophe JAILLET wrote:
>> Le 26/05/2023 ?? 08:02, Shradha Gupta a ??crit??:
>>> Allocate the size of rx indirection table dynamically in netvsc
>> >from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
>>> query instead of using a constant value of ITAB_NUM.
>>>
>>> Signed-off-by: Shradha Gupta <shradhagupta@...ux.microsoft.com>
>>> Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
>>> Testcases:
>>> 1. ethtool -x eth0 output
>>> 2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
>>> 3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV
>>>
>>> ---
>>
>> [...]
>>
>>> @@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
>>>   				struct netvsc_device *net_dev)
>>>   {
>>>   	struct rndis_device *rndis_dev = net_dev->extension;
>>> +	struct net_device *net = hv_get_drvdata(dev);
>>> +	struct net_device_context *ndc = netdev_priv(net);
>>>   	/* Halt and release the rndis device */
>>>   	rndis_filter_halt_device(net_dev, rndis_dev);
>>>   	netvsc_device_remove(dev);
>>> +
>>> +	ndc->rx_table_sz = 0;
>>> +	kfree(ndc->rx_table);
>>> +	ndc->rx_table = NULL;
>>> +
>>
>> Nit: useless empty NL
> This is to prevent any potential double free, or accessing freed memory, etc.
> As requested by Haiyang in v2 patch

Setting ndc->rx_table to NULL is fine, but there is a useless *newline* 
(NL) just after.
If you have to send a v4, you can save a line of code.

CJ

>>
>>>   }
>>>   int rndis_filter_open(struct netvsc_device *nvdev)
>