From patchwork Wed Jul 5 18:17:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= X-Patchwork-Id: 13302554 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 656D5EB64DD for ; Wed, 5 Jul 2023 18:18:42 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qH74X-0003Ze-Mt; Wed, 05 Jul 2023 14:17:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qH749-0003QP-9z for qemu-devel@nongnu.org; Wed, 05 Jul 2023 14:17:25 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qH747-0000YB-AB for qemu-devel@nongnu.org; Wed, 05 Jul 2023 14:17:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1688581042; 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; bh=U8MUn6OnKLBwA9MDj9K80DqgvwnS4/Ptdm548lSDEfE=; b=P6Dmk4iaPQrRZt/Mdms++B0efNv+1W3ukrzWXZ0IJbvwXOu5lm/qiEOGH12qi3mtCx+Z8l gwOAbSciHTLw75EjUAxu3+BSOy7OHaKQgfGmYrCeLD4D7Mk7E5BUPYwlVbRDfmctJD2KlV 9hhhGccB+wE3GWkMH6BLEgcpdEDyqPs= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-631-yoZScVauNg6zhocMFXncFA-1; Wed, 05 Jul 2023 14:17:20 -0400 X-MC-Unique: yoZScVauNg6zhocMFXncFA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6ADB4858290; Wed, 5 Jul 2023 18:17:20 +0000 (UTC) Received: from localhost.localdomain.com (unknown [10.42.28.145]) by smtp.corp.redhat.com (Postfix) with ESMTP id B881C2166B25; Wed, 5 Jul 2023 18:17:19 +0000 (UTC) From: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Mauro Matteo Cascella , jiangyegen Subject: [PATCH] io: remove io watch if TLS channel is closed during handshake Date: Wed, 5 Jul 2023 19:17:18 +0100 Message-ID: <20230705181718.387522-1-berrange@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org The TLS handshake make take some time to complete, during which time an I/O watch might be registered with the main loop. If the owner of the I/O channel invokes qio_channel_close() while the handshake is waiting to continue the I/O watch must be removed. Failing to remove it will later trigger the completion callback which the owner is not expecting to receive. In the case of the VNC server, this results in a SEGV as vnc_disconnect_start() tries to shutdown a client connection that is already gone / NULL. CVE-2023-3354 Reported-by: jiangyegen Signed-off-by: Daniel P. Berrangé --- include/io/channel-tls.h | 1 + io/channel-tls.c | 18 ++++++++++++------ 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/include/io/channel-tls.h b/include/io/channel-tls.h index 5672479e9e..26c67f17e2 100644 --- a/include/io/channel-tls.h +++ b/include/io/channel-tls.h @@ -48,6 +48,7 @@ struct QIOChannelTLS { QIOChannel *master; QCryptoTLSSession *session; QIOChannelShutdown shutdown; + guint hs_ioc_tag; }; /** diff --git a/io/channel-tls.c b/io/channel-tls.c index 9805dd0a3f..e327e6a5c2 100644 --- a/io/channel-tls.c +++ b/io/channel-tls.c @@ -198,12 +198,13 @@ static void qio_channel_tls_handshake_task(QIOChannelTLS *ioc, } trace_qio_channel_tls_handshake_pending(ioc, status); - qio_channel_add_watch_full(ioc->master, - condition, - qio_channel_tls_handshake_io, - data, - NULL, - context); + ioc->hs_ioc_tag = + qio_channel_add_watch_full(ioc->master, + condition, + qio_channel_tls_handshake_io, + data, + NULL, + context); } } @@ -218,6 +219,7 @@ static gboolean qio_channel_tls_handshake_io(QIOChannel *ioc, QIOChannelTLS *tioc = QIO_CHANNEL_TLS( qio_task_get_source(task)); + tioc->hs_ioc_tag = 0; g_free(data); qio_channel_tls_handshake_task(tioc, task, context); @@ -378,6 +380,10 @@ static int qio_channel_tls_close(QIOChannel *ioc, { QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc); + if (tioc->hs_ioc_tag) { + g_source_remove(tioc->hs_ioc_tag); + } + return qio_channel_close(tioc->master, errp); }