From nobody Sat Oct 4 16:44:34 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 1551423005413366.3045776952981; Thu, 28 Feb 2019 22:50:05 -0800 (PST) Received: from localhost ([127.0.0.1]:51748 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gzbzd-0005pR-5W for importer@patchew.org; Fri, 01 Mar 2019 01:50:01 -0500 Received: from eggs.gnu.org ([209.51.188.92]:39600) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gzbyj-0005Sa-A7 for qemu-devel@nongnu.org; Fri, 01 Mar 2019 01:49:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gzbyi-0000hV-J8 for qemu-devel@nongnu.org; Fri, 01 Mar 2019 01:49:05 -0500 Received: from mail-pl1-x642.google.com ([2607:f8b0:4864:20::642]:40472) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gzbyi-0000gz-Ba for qemu-devel@nongnu.org; Fri, 01 Mar 2019 01:49:04 -0500 Received: by mail-pl1-x642.google.com with SMTP id bj4so11005199plb.7 for ; Thu, 28 Feb 2019 22:49:04 -0800 (PST) Received: from localhost.localdomain ([2404:c807:f04:1f00:fb2d:97b9:72a7:5ed8]) by smtp.gmail.com with ESMTPSA id e21sm54049138pfh.45.2019.02.28.22.49.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 28 Feb 2019 22:49:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=tM1s6k/t6F9IASN/kpXYdlP8h5RGYDzxjBwiyhz0LhM=; b=qs7MrQXZc/hYL47CpgQ6o+L7ieFvN9v4fRzCZRXFdYSbUT/1ZtHOhyj9zQmWktBdev JbX2FUUx8rBWaEvfKhls4ic82WgmEozR08oHiZar4fv3DKn3Fsf1rYbRWNKntdo+VVH+ 0Kc6QOYpPgYlDUmnnJCDWQjDMN/hw9GrsbM/xcaVwEgITmiVIltEJzoqEc6/Gjh8VBtC cCFvr0f2ITFti1okOdpe3nVrnKsql24t8fappxzByr8bE/uN21wWe2Q1PM7N319sD/Px Xkz/23TdrNJOWUqJpzXxSwdVikPghrULTzFd+jFcSILOJaA8TydssYqcjeZMI5/WmZX4 0SHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=tM1s6k/t6F9IASN/kpXYdlP8h5RGYDzxjBwiyhz0LhM=; b=XFdeaKJnu6lZ6UGCpiJtLxoJ9APhSSGO76A8ZPmzsAeQQUN5qY7NsEPN0q4HeZGnjG EkV1LzF6Xcz+8Pnwrshhg/9ShtexQrDlfTjBFc6DPKYs14k0SYAjeZHKszCbWZIoffgi owcFjKBvsHzxNokqSnLHKMoOqmqSxyxM5ARUMcy/Xk2l7ooVdbV/2BiRo8GJVaPfyYNg UNXM0+rza1hS6olLP+cAuB5bi6Cl8VMciXqn/QRuZI/4uhubsufpRAPsyv6jFp9axo7V vQjMyGpBjKxt61NlYRWrTHNyGv93ZPAZpzgx7UofTl0/P7M/fsoKeYBSnBJrR1iO9kwX DWLg== X-Gm-Message-State: APjAAAWvZPNmagwnEPeL/d1eb6VRBoolFDvoY0XgFSNrZYcgfCNzqpYu 2eJYY9+qIi98U8cnG/jUeSAm9+rj2dY= X-Google-Smtp-Source: APXvYqzUZ09onRCi9z4sQwP2LtDkd6kj/Fr1YLTSoXSHkn/ZRccNMHrzvctCkP1/gxSP4HCggArCRg== X-Received: by 2002:a17:902:aa06:: with SMTP id be6mr3881039plb.57.1551422943310; Thu, 28 Feb 2019 22:49:03 -0800 (PST) From: Vic Lee To: qemu-devel@nongnu.org Date: Fri, 1 Mar 2019 14:48:09 +0800 Message-Id: <20190301064809.3074-1-llyzs.vic@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::642 Subject: [Qemu-devel] [PATCH v2] 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 , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Samuel Thibault Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" Sometimes sorecvfrom() is called from slirp.c because revents =3D=3D G_IO_I= N, 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 --- slirp/socket.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/slirp/socket.c b/slirp/socket.c index 4876ea3f31..03266128b1 100644 --- a/slirp/socket.c +++ b/slirp/socket.c @@ -529,6 +529,15 @@ sorecvfrom(struct socket *so) int n; #endif =20 + if (ioctlsocket(so->s, FIONREAD, &n) !=3D 0) { + DEBUG_MISC((dfd," ioctlsocket errno =3D %d-%s\n", + errno,strerror(errno))); + return; + } + if (n =3D=3D 0) { + return; + } + m =3D m_get(so->slirp); if (!m) { return; @@ -552,7 +561,6 @@ sorecvfrom(struct socket *so) */ len =3D M_FREEROOM(m); /* if (so->so_fport !=3D htons(53)) { */ - ioctlsocket(so->s, FIONREAD, &n); =20 if (n > len) { n =3D (m->m_data - m->m_dat) + m->m_len + n + 1; --=20 2.20.1