Re: [PATCH][next] bpf: fix swapped arguments in calls to check_buffer_access

From: Colin Ian King
Date: Tue Jul 28 2020 - 06:45:28 EST


On 28/07/2020 11:43, Daniel Borkmann wrote:
> On 7/27/20 11:39 PM, Yonghong Song wrote:
>> On 7/27/20 10:54 AM, Colin King wrote:
>>> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>>
>>> There are a couple of arguments of the boolean flag zero_size_allowed
>>> and the char pointer buf_info when calling to function
>>> check_buffer_access
>>> that are swapped by mistake. Fix these by swapping them to correct
>>> the argument ordering.
>>>
>>> Addresses-Coverity: ("Array compared to 0")
>>> Fixes: afbf21dce668 ("bpf: Support readonly/readwrite buffers in
>>> verifier")
>>> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>
>> Thanks for the fix!
>> Acked-by: Yonghong Song <yhs@xxxxxx>
>
> Sigh, thanks for the fix Colin, applied! Yonghong, could you follow-up with
> BPF selftest test cases that exercise these paths? Thx

No problem. Thanks to static analysis, it catches a lot of subtle bugs
like this.

Colin