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Subject: Re: [PATCH] net: sched: Fix a possible null-pointer dereference in
 dequeue_func()
To:     Jiri Pirko <jiri@resnulli.us>
Cc:     jhs@mojatatu.com, xiyou.wangcong@gmail.com, davem@davemloft.net,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20190729022157.18090-1-baijiaju1990@gmail.com>
 <20190729065653.GA2211@nanopsycho>
From:   Jia-Ju Bai <baijiaju1990@gmail.com>
Message-ID: <4752bf67-7a0c-7bc9-3d54-f18361085ba2@gmail.com>
Date:   Mon, 29 Jul 2019 15:32:00 +0800
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On 2019/7/29 14:56, Jiri Pirko wrote:
> Mon, Jul 29, 2019 at 04:21:57AM CEST, baijiaju1990@gmail.com wrote:
>> In dequeue_func(), there is an if statement on line 74 to check whether
>> skb is NULL:
>>     if (skb)
>>
>> When skb is NULL, it is used on line 77:
>>     prefetch(&skb->end);
>>
>> Thus, a possible null-pointer dereference may occur.
>>
>> To fix this bug, skb->end is used when skb is not NULL.
>>
>> This bug is found by a static analysis tool STCheck written by us.
>>
>> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
> Fixes tag, please?

Sorry, I do not know what "fixes tag" means...
I just find a possible bug and fix it in this patch.


Best wishes,
Jia-Ju Bai