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Message-ID: <5B9783ED.4080908@huawei.com>
Date:   Tue, 11 Sep 2018 16:59:25 +0800
From:   zhong jiang <zhongjiang@huawei.com>
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To:     Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
CC:     <davem@davemloft.net>, <edumazet@google.com>,
        <kuznet@ms2.inr.ac.ru>, <yoshfuji@linux-ipv6.org>,
        <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] net: ipv4: Use BUG_ON directly instead of a if condition
 followed by BUG
References: <1536590282-23899-1-git-send-email-zhongjiang@huawei.com> <a000b5a4-2907-70f9-70ed-7e1c6a797876@cogentembedded.com>
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On 2018/9/11 16:51, Sergei Shtylyov wrote:
> On 9/10/2018 5:38 PM, zhong jiang wrote:
>
>> The if condition can be removed if we use BUG_ON directly.
>> The issule is detected with the help of Coccinelle.
>
>   Issue?
>
>>
>> Signed-off-by: zhong jiang <zhongjiang@huawei.com>
>> ---
>>   net/ipv4/tcp_input.c | 8 ++++----
>>   1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
>> index 62508a2..893bde3 100644
>> --- a/net/ipv4/tcp_input.c
>> +++ b/net/ipv4/tcp_input.c
>> @@ -4934,8 +4934,8 @@ void tcp_rbtree_insert(struct rb_root *root, struct sk_buff *skb)
>>               BUG_ON(offset < 0);
>>               if (size > 0) {
>>                   size = min(copy, size);
>> -                if (skb_copy_bits(skb, offset, skb_put(nskb, size), size))
>> -                    BUG();
>> +                BUG(skb_copy_bits(skb, offset,
>
>    You said BUG_ON()?
 Yep. Do you think that it is worthing to do

 Thanks,
zhong jiang
>
>> +                          skb_put(nskb, size), size));
>>                   TCP_SKB_CB(nskb)->end_seq += size;
>>                   copy -= size;
>>                   start += size;
>> @@ -5327,8 +5327,8 @@ static void tcp_urg(struct sock *sk, struct sk_buff *skb, const struct tcphdr *t
>>           /* Is the urgent pointer pointing into this packet? */
>>           if (ptr < skb->len) {
>>               u8 tmp;
>> -            if (skb_copy_bits(skb, ptr, &tmp, 1))
>> -                BUG();
>> +
>> +            BUG(skb_copy_bits(skb, ptr, &tmp, 1));
>
>    Likewise.
>
> [...]
>
> MBR, Sergei
>
> .
>