08.01.2020 1:01, Eric Blake wrote:
> On 12/26/19 2:15 AM, Vladimir Sementsov-Ogievskiy wrote:
>> Don't try to write zero-lenght strings.
>
> length
>
>>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
>> ---
>> nbd/server.c | 16 ++++++++++------
>> 1 file changed, 10 insertions(+), 6 deletions(-)
>>
>> diff --git a/nbd/server.c b/nbd/server.c
>> index 24ebc1a805..28a915f5a2 100644
>> --- a/nbd/server.c
>> +++ b/nbd/server.c
>> @@ -392,14 +392,18 @@ static int nbd_negotiate_send_rep_list(NBDClient
>> *client, NBDExport *exp,
>> return -EINVAL;
>> }
>> - if (nbd_write(ioc, name, name_len, errp) < 0) {
>> - error_prepend(errp, "write failed (name buffer): ");
>> - return -EINVAL;
>> + if (name_len > 0) {
>> + if (nbd_write(ioc, name, name_len, errp) < 0) {
>
> What's the rationale for this change? nbd_write() should be a no-op
I looked through the code and it seems for me that nobody does this check,
so it would not be a no-op, at least it would be extra syscall..
> for a zero length write, at which point this is a micro-optimization (fewer
> CPU cycles, but no semantic change).
>
--
Best regards,
Vladimir
