Re: [PATCH] bpf: check NULL for sk_to_full_sk()

[YueHaibing]

On 2018/5/21 23:17, Eric Dumazet wrote:
> 
> 
> On 05/21/2018 12:55 AM, YueHaibing wrote:
>> like commit df39a9f106d5 ("bpf: check NULL for sk_to_full_sk() return value"),
>> we should check sk_to_full_sk return value against NULL.
>>
>> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
>> ---
>>  include/linux/bpf-cgroup.h | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
>> index 30d15e6..fd3fbeb 100644
>> --- a/include/linux/bpf-cgroup.h
>> +++ b/include/linux/bpf-cgroup.h
>> @@ -91,7 +91,7 @@ int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
>>  	int __ret = 0;							       \
>>  	if (cgroup_bpf_enabled && sk && sk == skb->sk) {		       \
>>  		typeof(sk) __sk = sk_to_full_sk(sk);			       \
>> -		if (sk_fullsock(__sk))					       \
>> +		if (__sk && sk_fullsock(__sk))				       \
>>  			__ret = __cgroup_bpf_run_filter_skb(__sk, skb,	       \
>>  						      BPF_CGROUP_INET_EGRESS); \
>>  	}								       \
>>
> 
> Why is this needed ???

BPF_CGROUP_RUN_PROG_INET_EGRESS is called in ip_output

I just misunderstood, sorry for noise.
> 
>