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Message-ID: <94ab0304-a674-3504-c1bd-3492e2ded0b1@blackwall.org>
Date:   Mon, 15 Aug 2022 10:32:13 +0300
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Subject: Re: [PATCH net-next] net: rtnetlink: fix module reference count leak
 issue in rtnetlink_rcv_msg
Content-Language: en-US
From:   Nikolay Aleksandrov <razor@blackwall.org>
To:     Zhengchao Shao <shaozhengchao@huawei.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, pabeni@redhat.com
Cc:     idosch@nvidia.com, petrm@nvidia.com, florent.fourcot@wifirst.fr,
        weiyongjun1@huawei.com, yuehaibing@huawei.com
References: <20220815024629.240367-1-shaozhengchao@huawei.com>
 <feff23c6-529c-3421-c48c-463846e59630@blackwall.org>
In-Reply-To: <feff23c6-529c-3421-c48c-463846e59630@blackwall.org>
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Precedence: bulk

On 15/08/2022 08:44, Nikolay Aleksandrov wrote:
> On 15/08/2022 05:46, Zhengchao Shao wrote:
>> When bulk delete command is received in the rtnetlink_rcv_msg function,
>> if bulk delete is not supported, module_put is not called to release
>> the reference counting. As a result, module reference count is leaked.
>>
>> Fixes: a6cec0bcd342("net: rtnetlink: add bulk delete support flag")
>> Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
>> ---
>>  net/core/rtnetlink.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
>> index ac45328607f7..4b5b15c684ed 100644
>> --- a/net/core/rtnetlink.c
>> +++ b/net/core/rtnetlink.c
>> @@ -6070,6 +6070,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
>>  	if (kind == RTNL_KIND_DEL && (nlh->nlmsg_flags & NLM_F_BULK) &&
>>  	    !(flags & RTNL_FLAG_BULK_DEL_SUPPORTED)) {
>>  		NL_SET_ERR_MSG(extack, "Bulk delete is not supported");
>> +		module_put(owner);
>>  		goto err_unlock;
>>  	}
>>  
> 
> Oops, thanks.
> Acked-by: Nikolay Aleksandrov <razor@blackwall.org>

By the way I think this should be targeted at -net,
I didn't notice the net-next tag earlier.