From nobody Sun Nov 9 13:00:07 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=gmail.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1551355247274175.58981251060982; Thu, 28 Feb 2019 04:00:47 -0800 (PST) Received: from localhost ([127.0.0.1]:36945 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gzKMe-00044W-L3 for importer@patchew.org; Thu, 28 Feb 2019 07:00:36 -0500 Received: from eggs.gnu.org ([209.51.188.92]:46574) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gzKLe-0003mK-Og for qemu-devel@nongnu.org; Thu, 28 Feb 2019 06:59:35 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gzKLa-0001yA-I7 for qemu-devel@nongnu.org; Thu, 28 Feb 2019 06:59:32 -0500 Received: from mail-io1-xd44.google.com ([2607:f8b0:4864:20::d44]:35754) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gzKLW-0001xn-Ps for qemu-devel@nongnu.org; Thu, 28 Feb 2019 06:59:28 -0500 Received: by mail-io1-xd44.google.com with SMTP id x4so16387713ion.2 for ; Thu, 28 Feb 2019 03:59:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to:cc; bh=852kdNMk7jDGnxYsGVvowhKGQkx8K2YENNFlkLBTcXk=; b=b2ljM8JxHZGOmGqSvrSfN5wbwDa+jbaS1BlN9ASWcnvvemrfrhFZ7Oh8XFPjB4AbvE 6F1d7bSjOGDG0vYhsIEtdfUHc39Lwy6f5J6xNPxLAuf8mdZqThtCX3jyZwpuZNHWHQp4 4roPiVVBh00dspKn42cCKEHksWWtsIMZrMTox05RefbU+OoxREPwqF9gq8VzfFn2gBBx aQ9hB/CSYx8ZUCzqzE+EApISgCVKJYlSGj5gTmjsDbTEshz+UpAZ1pY5c7+rUcvBCqh4 yBIbusyVuye1iZdLAE/qU5lHenlbh+wabi2ticiuG36plLJ03+ASiX4MHRPGRC8g80hw bzXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to:cc; bh=852kdNMk7jDGnxYsGVvowhKGQkx8K2YENNFlkLBTcXk=; b=qtKla05wZkwYQpyh1EJRyx1fVRwD51V59tyoSJzwNsDZz7aUvE3ENWBf+7vyleKd+g LJ/138P8h/MYCNI0nf6HYz65zXsuqpfYOc+FZYR/5Y2S7ScRYuAO146oVIgfemOzewk4 Ek4kawOXllv70FggdchCH1uxUPH6X+dBIlNgxxWsx1cQBR1Y/xdMq0doZW/uAjxPc9mD /6O8/wPBg7DndPFO+3SWlV0LVI0XXBCk07jxYTRrCjYprvgY4Wx8fSIETB5qa4GQ9rzG H//m+3OQO5RSrdqvbOBtg6ZZwvi8+/0wUipmHpWkpyj3tMjgUWWiEuuMUju6BTShehB2 nzUA== X-Gm-Message-State: APjAAAUcZJUTwp0zmGDUiaWJd2ODZAqgLOsXjuGztbLMGExrxEORdvim XpiF3z3cJeP+acm5SkYbEZtHBgVcbebmLr60fXt9kBH0 X-Google-Smtp-Source: APXvYqzymHdstUS1nhYZ3IH14xkHeuE6SLvwnVDHrza5VAr9wJqClbecVMJkA8BosadA2II3CyWBa5tQHUsLkzIOxE8= X-Received: by 2002:a6b:2c58:: with SMTP id s85mr4716199ios.274.1551355162801; Thu, 28 Feb 2019 03:59:22 -0800 (PST) MIME-Version: 1.0 From: llyzs Date: Thu, 28 Feb 2019 19:59:12 +0800 Message-ID: To: qemu-devel@nongnu.org X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::d44 Subject: [Qemu-devel] [PATCH] socket: fix blocking udp recvfrom. X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Samuel Thibault , =?UTF-8?B?TWFyYy1BbmRyw6kgTHVyZWF1?= , Jan Kiszka Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Sometimes sorecvfrom() is called from slirp.c because revents =3D=3D G_IO_I= N, however inside sorecvfrom() function, ioctlsocket() returns 0 bytes availab= le and recvfrom could be blocking indefinitely. This adds a non-blocking flag = to recvfrom and checks data availability. --- slirp/socket.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/slirp/socket.c b/slirp/socket.c index c01d8696af..ea30478ce6 100644 --- a/slirp/socket.c +++ b/slirp/socket.c @@ -581,7 +581,7 @@ sorecvfrom(struct socket *so) } /* } */ - m->m_len =3D recvfrom(so->s, m->m_data, len, 0, + m->m_len =3D recvfrom(so->s, m->m_data, len, MSG_DONTWAIT, (struct sockaddr *)&addr, &addrlen); DEBUG_MISC((dfd, " did recvfrom %d, errno =3D %d-%s\n", m->m_len, errno,strerror(errno))); @@ -618,6 +618,8 @@ sorecvfrom(struct socket *so) break; } m_free(m); + } else if (m->m_len=3D=3D0) { + m_free(m); } else { /* * Hack: domain name lookup will be used the most for UDP, --=20 2.20.1