From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48480) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eCowv-0000Yi-1z for qemu-devel@nongnu.org; Thu, 09 Nov 2017 10:41:02 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eCowq-0006yf-5p for qemu-devel@nongnu.org; Thu, 09 Nov 2017 10:41:01 -0500 Received: from mailhub.sw.ru ([195.214.232.25]:46397 helo=relay.sw.ru) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eCowp-0006wq-QG for qemu-devel@nongnu.org; Thu, 09 Nov 2017 10:40:56 -0500 From: Vladimir Sementsov-Ogievskiy Date: Thu, 9 Nov 2017 18:40:48 +0300 Message-Id: <20171109154049.42386-2-vsementsov@virtuozzo.com> In-Reply-To: <20171109154049.42386-1-vsementsov@virtuozzo.com> References: <20171109154049.42386-1-vsementsov@virtuozzo.com> Subject: [Qemu-devel] [PATCH 1/2] nbd/server: add additional assert to nbd_export_put List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org, qemu-devel@nongnu.org Cc: eblake@redhat.com, pbonzini@redhat.com, kwolf@redhat.com, mreitz@redhat.com, armbru@redhat.com, vsementsov@virtuozzo.com, den@openvz.org This place is not obvious, nbd_export_close may theoretically reduce refcount to 0. It may happen if someone calls nbd_export_put on named export not through nbd_export_set_name when refcount is 1. Signed-off-by: Vladimir Sementsov-Ogievskiy --- nbd/server.c | 1 + 1 file changed, 1 insertion(+) diff --git a/nbd/server.c b/nbd/server.c index 70b40ed27e..2f2e05943f 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -1179,6 +1179,7 @@ void nbd_export_put(NBDExport *exp) nbd_export_close(exp); } + assert(exp->refcount > 0); if (--exp->refcount == 0) { assert(exp->name == NULL); assert(exp->description == NULL); -- 2.11.1