From patchwork Fri Mar 22 20:31:07 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luiz Capitulino X-Patchwork-Id: 230251 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id AB1EC2C00D1 for ; Sat, 23 Mar 2013 07:31:31 +1100 (EST) Received: from localhost ([::1]:41360 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UJ8cb-00064m-Ms for incoming@patchwork.ozlabs.org; Fri, 22 Mar 2013 16:31:29 -0400 Received: from eggs.gnu.org ([208.118.235.92]:50369) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UJ8cK-00064W-AE for qemu-devel@nongnu.org; Fri, 22 Mar 2013 16:31:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UJ8cJ-00022E-Af for qemu-devel@nongnu.org; Fri, 22 Mar 2013 16:31:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:64925) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UJ8cJ-00021v-3n for qemu-devel@nongnu.org; Fri, 22 Mar 2013 16:31:11 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r2MKV8Qk016838 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 22 Mar 2013 16:31:08 -0400 Received: from doriath (ovpn-113-108.phx2.redhat.com [10.3.113.108]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r2MKV7Xe008197; Fri, 22 Mar 2013 16:31:07 -0400 Date: Fri, 22 Mar 2013 16:31:07 -0400 From: Luiz Capitulino To: qemu-devel Message-ID: <20130322163107.489dd941@doriath> Organization: Red Hat Mime-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: mdroth@linux.vnet.ibm.com Subject: [Qemu-devel] [PATCH] qemu-ga: ga_get_fd_handle(): abort if fd_counter overflows X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Today we reset fd_counter if it wraps, but it's better to abort() instead, as fd_counter should never reach INT64_MAX. Signed-off-by: Luiz Capitulino Reviewed-by: Eric Blake --- qga/main.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/qga/main.c b/qga/main.c index 74ef788..5f505a2 100644 --- a/qga/main.c +++ b/qga/main.c @@ -889,9 +889,13 @@ int64_t ga_get_fd_handle(GAState *s, Error **errp) g_assert(!ga_is_frozen(s)); handle = s->pstate.fd_counter++; - if (s->pstate.fd_counter < 0) { - s->pstate.fd_counter = 0; + + /* This should never happen on a resonable timeframe, as guest-file-open + * would have to be issued 2^63 times */ + if (s->pstate.fd_counter == INT64_MAX) { + abort(); } + if (!write_persistent_state(&s->pstate, s->pstate_filepath)) { error_setg(errp, "failed to commit persistent state to disk"); }