From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DFBA7C433F5 for ; Sat, 8 Jan 2022 01:29:42 +0000 (UTC) Received: from localhost ([::1]:55374 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1n60Y9-0007iq-Sx for qemu-devel@archiver.kernel.org; Fri, 07 Jan 2022 20:29:41 -0500 Received: from eggs.gnu.org ([209.51.188.92]:43908) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n609l-00046m-1d for qemu-devel@nongnu.org; Fri, 07 Jan 2022 20:04:29 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:53402) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n609j-0002MU-LV for qemu-devel@nongnu.org; Fri, 07 Jan 2022 20:04:28 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1641603867; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=5NmSRsYDHdSt3mPPWE/VBrC0tl4EEty9M7O4eh0ePIo=; b=d7lNwRmqyhxQ1ehco4gcdUNWxwPyxZ59HrlyaR4mtCWVNB+0YSQO/JAlkv4MR/Icn5lRb4 EJUiUchCrymsQ0cFgh0snwM7z5IzVDoUfo3KhCqc3LjWh97VCdylduy4ymOiMlWvlBIYOX TV0WpLxQiwNLyJlghS1v/tuzHwdbcmA= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-101-egOplCHNPTq1XM169M4_XA-1; Fri, 07 Jan 2022 20:04:26 -0500 X-MC-Unique: egOplCHNPTq1XM169M4_XA-1 Received: by mail-wm1-f69.google.com with SMTP id m21-20020a7bcf35000000b00346ddc490efso2497673wmg.8 for ; Fri, 07 Jan 2022 17:04:26 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=5NmSRsYDHdSt3mPPWE/VBrC0tl4EEty9M7O4eh0ePIo=; b=2+WoAGAG/JKEOZI/Z1mH97X3pIJX17pKGof3fmKWQSJLHPVgSrRw1eoI2Z9AZrXYyi 1r011xRSeqP0oc93cTcuVV1Jm7aubNhE1IyPMVuzsC2leWi5oTD+6MNKJR/qh/3lcFMl ZCcUO+ToTx8KvQkMXeEMGxLjoyfArMYiTMTqhTXgVvQG75SD8kCN/2ORute3SpeNA7NT PM9ASxAnRNqZZ4OC1oS4oF+/6qD3IunG+oRSqBjP/q7xX3jbWhmblPpQpDNQzhdU2t33 IlyG40b8kjGWA4bV64qGHnmB5wYRhkXedMMb0oFGUDh78/wIN+92HL63zu8CVqBqLvkW Mzaw== X-Gm-Message-State: AOAM533++/y+I0K0qpvTLGioJ0x4jeHbZOd1BZXrSBiANh6VooEJOAi9 bdgaI+MMcVFzA8ziQ5CetLuKbWNsIukJ43BjYraIsbIU0hptBh2zsGO7Ed7uMSKrvTrxXjEUqm1 SHn/NP57GDxHeDr9X5zdrPGppIRvAFv9W3ERk/WCHe3Bzg4lRSLdMGcnq8A3j X-Received: by 2002:adf:d226:: with SMTP id k6mr54825289wrh.243.1641603864765; Fri, 07 Jan 2022 17:04:24 -0800 (PST) X-Google-Smtp-Source: ABdhPJxhy2YNW4X5klWUK/rIBC0b0CpDtbvmokMT2AgnqOWVBhj4uK5+O5t3OYpqoZM0CPuhO1nilw== X-Received: by 2002:adf:d226:: with SMTP id k6mr54825271wrh.243.1641603864456; Fri, 07 Jan 2022 17:04:24 -0800 (PST) Received: from redhat.com ([147.161.13.99]) by smtp.gmail.com with ESMTPSA id p11sm245057wru.99.2022.01.07.17.04.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 07 Jan 2022 17:04:23 -0800 (PST) Date: Fri, 7 Jan 2022 20:04:21 -0500 From: "Michael S. Tsirkin" To: qemu-devel@nongnu.org Subject: [PULL v3 16/55] chardev/char-socket: tcp_chr_sync_read: don't clobber errno Message-ID: <20220108003423.15830-17-mst@redhat.com> References: <20220108003423.15830-1-mst@redhat.com> MIME-Version: 1.0 In-Reply-To: <20220108003423.15830-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mst@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.129.124; envelope-from=mst@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.372, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Roman Kagan , Peter Maydell , Paolo Bonzini , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Roman Kagan After the return from tcp_chr_recv, tcp_chr_sync_read calls into a function which eventually makes a system call and may clobber errno. Make a copy of errno right after tcp_chr_recv and restore the errno on return from tcp_chr_sync_read. Signed-off-by: Roman Kagan Message-Id: <20211111153354.18807-4-rvkagan@yandex-team.ru> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Reviewed-by: Marc-André Lureau --- chardev/char-socket.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/chardev/char-socket.c b/chardev/char-socket.c index 3ddd98ed49..fab2d791d4 100644 --- a/chardev/char-socket.c +++ b/chardev/char-socket.c @@ -525,6 +525,7 @@ static int tcp_chr_sync_read(Chardev *chr, const uint8_t *buf, int len) { SocketChardev *s = SOCKET_CHARDEV(chr); int size; + int saved_errno; if (s->state != TCP_CHARDEV_STATE_CONNECTED) { return 0; @@ -532,6 +533,7 @@ static int tcp_chr_sync_read(Chardev *chr, const uint8_t *buf, int len) qio_channel_set_blocking(s->ioc, true, NULL); size = tcp_chr_recv(chr, (void *) buf, len); + saved_errno = errno; if (s->state != TCP_CHARDEV_STATE_DISCONNECTED) { qio_channel_set_blocking(s->ioc, false, NULL); } @@ -540,6 +542,7 @@ static int tcp_chr_sync_read(Chardev *chr, const uint8_t *buf, int len) tcp_chr_disconnect(chr); } + errno = saved_errno; return size; } -- MST