From patchwork Mon Aug 18 19:26:27 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luiz Capitulino X-Patchwork-Id: 381106 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 5D1E0140095 for ; Tue, 19 Aug 2014 05:27:36 +1000 (EST) Received: from localhost ([::1]:45329 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XJSac-0005eT-83 for incoming@patchwork.ozlabs.org; Mon, 18 Aug 2014 15:27:34 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37799) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XJSZz-0004dD-UO for qemu-devel@nongnu.org; Mon, 18 Aug 2014 15:27:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XJSZu-0002jT-5L for qemu-devel@nongnu.org; Mon, 18 Aug 2014 15:26:55 -0400 Received: from mx1.redhat.com ([209.132.183.28]:23712) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XJSZt-0002jN-RJ for qemu-devel@nongnu.org; Mon, 18 Aug 2014 15:26:50 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s7IJQeNM026473 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 18 Aug 2014 15:26:40 -0400 Received: from localhost (ovpn-116-28.ams2.redhat.com [10.36.116.28]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s7IJQcWe017372; Mon, 18 Aug 2014 15:26:39 -0400 From: Luiz Capitulino To: peter.maydell@linaro.org Date: Mon, 18 Aug 2014 15:26:27 -0400 Message-Id: <1408389987-27831-4-git-send-email-lcapitulino@redhat.com> In-Reply-To: <1408389987-27831-1-git-send-email-lcapitulino@redhat.com> References: <1408389987-27831-1-git-send-email-lcapitulino@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: qemu-devel@nongnu.org, anthony@codemonkey.ws Subject: [Qemu-devel] [PULL 3/3] monitor: fix use after free 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 From: "Michael S. Tsirkin" The function monitor_fdset_dup_fd_find_remove() references member of 'mon_fdset' which - when remove flag is set - may be freed in function monitor_fdset_cleanup(). remove is set by monitor_fdset_dup_fd_remove which in practice does not need the returned value, so make it void, and return -1 from monitor_fdset_dup_fd_find_remove. Reported-by: zhanghailiang Signed-off-by: Michael S. Tsirkin Signed-off-by: Luiz Capitulino --- include/monitor/monitor.h | 2 +- monitor.c | 8 +++++--- stubs/fdset-remove-fd.c | 3 +-- 3 files changed, 7 insertions(+), 6 deletions(-) diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h index 3d6929d..78a5fc8 100644 --- a/include/monitor/monitor.h +++ b/include/monitor/monitor.h @@ -64,7 +64,7 @@ AddfdInfo *monitor_fdset_add_fd(int fd, bool has_fdset_id, int64_t fdset_id, Error **errp); int monitor_fdset_get_fd(int64_t fdset_id, int flags); int monitor_fdset_dup_fd_add(int64_t fdset_id, int dup_fd); -int monitor_fdset_dup_fd_remove(int dup_fd); +void monitor_fdset_dup_fd_remove(int dup_fd); int monitor_fdset_dup_fd_find(int dup_fd); #endif /* !MONITOR_H */ diff --git a/monitor.c b/monitor.c index 48f0fdc..34cee74 100644 --- a/monitor.c +++ b/monitor.c @@ -2542,8 +2542,10 @@ static int monitor_fdset_dup_fd_find_remove(int dup_fd, bool remove) if (QLIST_EMPTY(&mon_fdset->dup_fds)) { monitor_fdset_cleanup(mon_fdset); } + return -1; + } else { + return mon_fdset->id; } - return mon_fdset->id; } } } @@ -2555,9 +2557,9 @@ int monitor_fdset_dup_fd_find(int dup_fd) return monitor_fdset_dup_fd_find_remove(dup_fd, false); } -int monitor_fdset_dup_fd_remove(int dup_fd) +void monitor_fdset_dup_fd_remove(int dup_fd) { - return monitor_fdset_dup_fd_find_remove(dup_fd, true); + monitor_fdset_dup_fd_find_remove(dup_fd, true); } int monitor_handle_fd_param(Monitor *mon, const char *fdname) diff --git a/stubs/fdset-remove-fd.c b/stubs/fdset-remove-fd.c index b3886d9..7f6d61e 100644 --- a/stubs/fdset-remove-fd.c +++ b/stubs/fdset-remove-fd.c @@ -1,7 +1,6 @@ #include "qemu-common.h" #include "monitor/monitor.h" -int monitor_fdset_dup_fd_remove(int dupfd) +void monitor_fdset_dup_fd_remove(int dupfd) { - return -1; }