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SubjectRe: [PATCH] kernel: bpf: remove dead code
Hi David,

Quoting David Miller <davem@davemloft.net>:

> From: "Gustavo A. R. Silva" <garsilva@embeddedor.com>
> Date: Mon, 22 May 2017 09:07:46 -0500
>
>> Execution cannot reach NET_IP_ALIGN inside the following statement:
>> ip_align = strict ? 2 : NET_IP_ALIGN
>>
>> Addresses-Coverity-ID: 1409762
>> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
>> ---
>> NOTE: variable ip_align could also be removed and use value 2 directly.
>
> Incorrect.
>
> Some platforms define NET_IP_ALIGN to zero, so the code must remain
> as is.

The following piece of code at kernel/bpf/verifier.c:798 is preventing
value NET_IP_ALIGN to be stored in variable ip_align when _strict_ is
false:

798 if (!strict || size == 1)
799 return 0;


Thanks
--
Gustavo A. R. Silva




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