Re: [Qemu-devel] [PATCH] qemu-char: check errno together with ret < 0

[Paolo Bonzini <pbonzini@redhat.com>]

On 04/07/2018 11:36, Marc-André Lureau wrote:
> On Wed, Jul 4, 2018 at 5:36 AM, xinhua.Cao <caoxinhua@huawei.com> wrote:
>> In the tcp_chr_write function, we checked errno,
>> but errno was not reset before a read or write operation.
>> Therefore, this check of errno's actions is often
>> incorrect after EAGAIN has occurred.
>> we need check errno together with ret < 0.
>>
>> Signed-off-by: xinhua.Cao <caoxinhua@huawei.com>
> 
> 
> Can you point out this is fixing commit
> 9fc53a10f81d3a9027b23fa810147d21be29e614 in commit message?

Ok, done.

Thanks,

Paolo

> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
>> ---
>>  chardev/char-socket.c | 7 +++++--
>>  1 file changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/chardev/char-socket.c b/chardev/char-socket.c
>> index 17519ec..efbad6e 100644
>> --- a/chardev/char-socket.c
>> +++ b/chardev/char-socket.c
>> @@ -134,8 +134,11 @@ static int tcp_chr_write(Chardev *chr, const uint8_t *buf, int len)
>>                                          s->write_msgfds,
>>                                          s->write_msgfds_num);
>>
>> -        /* free the written msgfds in any cases other than errno==EAGAIN */
>> -        if (EAGAIN != errno && s->write_msgfds_num) {
>> +        /* free the written msgfds in any cases
>> +         * other than ret < 0 && errno == EAGAIN
>> +         */
>> +        if (!(ret < 0 && EAGAIN == errno)
>> +            && s->write_msgfds_num) {
>>              g_free(s->write_msgfds);
>>              s->write_msgfds = 0;
>>              s->write_msgfds_num = 0;
>> --
>> 2.8.3
>>
>>
>>
> 
> 
>