From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 0261F424A0; Fri, 27 Jan 2023 17:56:01 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 4F52642D54; Fri, 27 Jan 2023 17:55:53 +0100 (CET) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mails.dpdk.org (Postfix) with ESMTP id 6B4A940695 for ; Fri, 27 Jan 2023 17:55:51 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1674838551; 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=36YJtjCWYppfEqWqLJ6ZCFt36AXYxDkAOe+BxUsczSQ=; b=Wq8VSmD5JIfuXUzP7AuIVwxns3pP0Jw0wlSPfr7qq8f9q39FPRPb7Ha+BL5btixzjpjPQa cY7eJ+hjt1RqeXrFMfx/J2MjXA/SAVV1cgw0O3F5kddImYZl+yDN/vDx4Fv6N66ab3l+Ni /G4gSUHFCCm/H3ezW5bcNEEsMBlb6BE= 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-46-nTy4QXTmMo-eKGrGXXcXHQ-1; Fri, 27 Jan 2023 11:55:46 -0500 X-MC-Unique: nTy4QXTmMo-eKGrGXXcXHQ-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6B50C858F09; Fri, 27 Jan 2023 16:55:46 +0000 (UTC) Received: from max-t490s.redhat.com (unknown [10.39.208.33]) by smtp.corp.redhat.com (Postfix) with ESMTP id 46FAF492B01; Fri, 27 Jan 2023 16:55:45 +0000 (UTC) From: Maxime Coquelin To: dev@dpdk.org, david.marchand@redhat.com, chenbo.xia@intel.com Cc: Maxime Coquelin , stable@dpdk.org Subject: [PATCH v2 2/2] vhost: fix possible FD leaks on MSG_TRUNC and MSG_CTRUNC Date: Fri, 27 Jan 2023 17:55:39 +0100 Message-Id: <20230127165540.37863-3-maxime.coquelin@redhat.com> In-Reply-To: <20230127165540.37863-1-maxime.coquelin@redhat.com> References: <20230127165540.37863-1-maxime.coquelin@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII"; x-default=true X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org This patch fixes possible FDs leaks when truncation happens on either the message buffer or its control data. Indeed, by returning early, it did not let a chance to retrieve the FDs passed as ancillary data, and so caused a potential FDs leak. This patch fixes this by extracting the FDs from the ancillary data as long as recvmsg() call succeeded. It also improves the logs to differentiate between MSG_TRUNC and MSG_CTRUNC. Fixes: bf472259dde6 ("vhost: fix possible denial of service by leaking FDs") Cc: stable@dpdk.org Signed-off-by: Maxime Coquelin --- lib/vhost/socket.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/lib/vhost/socket.c b/lib/vhost/socket.c index 863a6f6d52..669c322e12 100644 --- a/lib/vhost/socket.c +++ b/lib/vhost/socket.c @@ -129,10 +129,12 @@ read_fd_message(char *ifname, int sockfd, char *buf, int buflen, int *fds, int m return ret; } - if (msgh.msg_flags & (MSG_TRUNC | MSG_CTRUNC)) { + if (msgh.msg_flags & MSG_TRUNC) VHOST_LOG_CONFIG(ifname, ERR, "truncated msg (fd %d)\n", sockfd); - return -1; - } + + /* MSG_CTRUNC may be caused by LSM misconfiguration */ + if (msgh.msg_flags & MSG_CTRUNC) + VHOST_LOG_CONFIG(ifname, ERR, "truncated control data (fd %d)\n", sockfd); for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL; cmsg = CMSG_NXTHDR(&msgh, cmsg)) { -- 2.39.1