From patchwork Thu Mar 7 11:51:33 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Samuel Thibault X-Patchwork-Id: 1052804 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ens-lyon.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 44FTXJ3mH2z9sBF for ; Thu, 7 Mar 2019 22:52:48 +1100 (AEDT) Received: from localhost ([127.0.0.1]:49741 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h1rZu-0008Ns-Cu for incoming@patchwork.ozlabs.org; Thu, 07 Mar 2019 06:52:46 -0500 Received: from eggs.gnu.org ([209.51.188.92]:36093) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h1rYz-0008NH-Mg for qemu-devel@nongnu.org; Thu, 07 Mar 2019 06:51:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1h1rYy-0003UN-Ua for qemu-devel@nongnu.org; Thu, 07 Mar 2019 06:51:49 -0500 Received: from hera.aquilenet.fr ([2a0c:e300::1]:35498) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1h1rYy-0003Tu-Nn for qemu-devel@nongnu.org; Thu, 07 Mar 2019 06:51:48 -0500 Received: from localhost (localhost [127.0.0.1]) by hera.aquilenet.fr (Postfix) with ESMTP id 34443B15D; Thu, 7 Mar 2019 12:51:47 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at aquilenet.fr Received: from hera.aquilenet.fr ([127.0.0.1]) by localhost (hera.aquilenet.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 6iMdj3i8hPv8; Thu, 7 Mar 2019 12:51:46 +0100 (CET) Received: from function (dhcp-13-128.lip.ens-lyon.fr [140.77.13.128]) by hera.aquilenet.fr (Postfix) with ESMTPSA id 5B56AB15F; Thu, 7 Mar 2019 12:51:44 +0100 (CET) Received: from samy by function with local (Exim 4.92) (envelope-from ) id 1h1rYt-0000Dj-CQ; Thu, 07 Mar 2019 12:51:43 +0100 From: Samuel Thibault To: qemu-devel@nongnu.org Date: Thu, 7 Mar 2019 12:51:33 +0100 Message-Id: <20190307115143.780-4-samuel.thibault@ens-lyon.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190307115143.780-1-samuel.thibault@ens-lyon.org> References: <20190307115143.780-1-samuel.thibault@ens-lyon.org> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2a0c:e300::1 Subject: [Qemu-devel] [PULLv2 02/12] slirp: check for ioctlsocket error and 0-length udp payload. 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: Vic Lee , jan.kiszka@siemens.com, Samuel Thibault , stefanha@redhat.com, peter.maydell@linaro.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Vic Lee Sometimes sorecvfrom() is called from slirp.c because revents == G_IO_IN, but there is 0 bytes available and recvfrom could be blocking indefinitely. This is likely due to 0-length udp payload. This also adds an error checking for ioctlsocket. Signed-off-by: Vic Lee Message-Id: <20190301064809.3074-1-llyzs.vic@gmail.com> Signed-off-by: Samuel Thibault --- slirp/socket.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/slirp/socket.c b/slirp/socket.c index 4876ea3f31..4dc5e2907d 100644 --- a/slirp/socket.c +++ b/slirp/socket.c @@ -529,6 +529,15 @@ sorecvfrom(struct socket *so) int n; #endif + if (ioctlsocket(so->s, FIONREAD, &n) != 0) { + DEBUG_MISC(" ioctlsocket errno = %d-%s\n", + errno,strerror(errno)); + return; + } + if (n == 0) { + return; + } + m = m_get(so->slirp); if (!m) { return; @@ -552,7 +561,6 @@ sorecvfrom(struct socket *so) */ len = M_FREEROOM(m); /* if (so->so_fport != htons(53)) { */ - ioctlsocket(so->s, FIONREAD, &n); if (n > len) { n = (m->m_data - m->m_dat) + m->m_len + n + 1;