From patchwork Thu Feb 16 23:02:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Williamson X-Patchwork-Id: 13144106 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 7010BC636CC for ; Thu, 16 Feb 2023 23:02:53 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pSnGT-0001u2-FS; Thu, 16 Feb 2023 18:02:09 -0500 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 1pSnGR-0001sf-4a for qemu-devel@nongnu.org; Thu, 16 Feb 2023 18:02:07 -0500 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 1pSnGP-0005VA-DN for qemu-devel@nongnu.org; Thu, 16 Feb 2023 18:02:06 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1676588524; 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=857s7AC1o9Ddl3Egm9bSzaKXqSlKe9oyjZdSnctUAbs=; b=KwOCIVrfKp8+wdjoeqdTLVCWFINZfcjCnHhl4saBsggYRFO8g2yOiYQBwAJ/6avPm75Y8N SbxvuhM2GfyCmAF3w0NI13BJ/JHThOW4sB1rB1GRpHMD3GGggJSmKDYvz5Etpan7429HMd 7qfg1DnhEAabBIjvxoQmCcYYQ7quo/M= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-3-pENo0osJPUKng0WJS7S7Jw-1; Thu, 16 Feb 2023 18:02:01 -0500 X-MC-Unique: pENo0osJPUKng0WJS7S7Jw-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 E2AD529324AA; Thu, 16 Feb 2023 23:02:00 +0000 (UTC) Received: from [172.30.41.16] (unknown [10.22.32.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id 923C82166B30; Thu, 16 Feb 2023 23:02:00 +0000 (UTC) Subject: [PULL 02/12] vfio/migration: Fix NULL pointer dereference bug From: Alex Williamson To: qemu-devel@nongnu.org Cc: alex.williamson@redhat.com, avihaih@nvidia.com, clg@redhat.com Date: Thu, 16 Feb 2023 16:02:00 -0700 Message-ID: <167658852016.932837.13243210499133474787.stgit@omen> In-Reply-To: <167658846945.932837.1420176491103357684.stgit@omen> References: <167658846945.932837.1420176491103357684.stgit@omen> User-Agent: StGit/1.5.dev2+g9ce680a52bd9 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=alex.williamson@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_H2=-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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Avihai Horon As part of its error flow, vfio_vmstate_change() accesses MigrationState->to_dst_file without any checks. This can cause a NULL pointer dereference if the error flow is taken and MigrationState->to_dst_file is not set. For example, this can happen if VM is started or stopped not during migration and vfio_vmstate_change() error flow is taken, as MigrationState->to_dst_file is not set at that time. Fix it by checking that MigrationState->to_dst_file is set before using it. Fixes: 02a7e71b1e5b ("vfio: Add VM state change handler to know state of VM") Signed-off-by: Avihai Horon Reviewed-by: Juan Quintela Reviewed-by: Vladimir Sementsov-Ogievskiy Link: https://lore.kernel.org/r/20230216143630.25610-3-avihaih@nvidia.com Signed-off-by: Alex Williamson --- hw/vfio/migration.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index 83d2d44080a6..65f3f3bef795 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -741,7 +741,9 @@ static void vfio_vmstate_change(void *opaque, bool running, RunState state) */ error_report("%s: Failed to set device state 0x%x", vbasedev->name, (migration->device_state & mask) | value); - qemu_file_set_error(migrate_get_current()->to_dst_file, ret); + if (migrate_get_current()->to_dst_file) { + qemu_file_set_error(migrate_get_current()->to_dst_file, ret); + } } vbasedev->migration->vm_running = running; trace_vfio_vmstate_change(vbasedev->name, running, RunState_str(state),