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Subject: Re: [PATCH bpf-next v2 2/4] bpf, sockmap: Fix memleak in
 tcp_bpf_sendmsg while sk msg is full
To:     Cong Wang <xiyou.wangcong@gmail.com>
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ÔÚ 2022/3/3 8:48, Cong Wang дµÀ:
> On Wed, Mar 02, 2022 at 10:27:53AM +0800, Wang Yufen wrote:
>> diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c
>> index 9b9b02052fd3..ac9f491cc139 100644
>> --- a/net/ipv4/tcp_bpf.c
>> +++ b/net/ipv4/tcp_bpf.c
>> @@ -421,8 +421,10 @@ static int tcp_bpf_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
>>   		osize = msg_tx->sg.size;
>>   		err = sk_msg_alloc(sk, msg_tx, msg_tx->sg.size + copy, msg_tx->sg.end - 1);
>>   		if (err) {
>> -			if (err != -ENOSPC)
>> +			if (err != -ENOSPC) {
>> +				sk_msg_trim(sk, msg_tx, osize);
>>   				goto wait_for_memory;
> Is it a good idea to handle this logic inside sk_msg_alloc()?

Yes, I think you're right.

Other call paths of sk_msg_alloc() have the similar problem, such as 
tls_sw_sendmsg(),

will do in v3.


Thanks.

> .