From mboxrd@z Thu Jan 1 00:00:00 1970
Return-Path: <dev-bounces@dpdk.org>
Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124])
by inbox.dpdk.org (Postfix) with ESMTP id A202B43DFB;
Thu, 4 Apr 2024 19:15:37 +0200 (CEST)
Received: from mails.dpdk.org (localhost [127.0.0.1])
by mails.dpdk.org (Postfix) with ESMTP id B40CF40A6E;
Thu, 4 Apr 2024 19:15:20 +0200 (CEST)
Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182])
by mails.dpdk.org (Postfix) with ESMTP id 105FB4064A
for <dev@dpdk.org>; Thu, 4 Apr 2024 19:15:15 +0200 (CEST)
Received: by linux.microsoft.com (Postfix, from userid 1086)
id 63C3A20E97C1; Thu, 4 Apr 2024 10:15:14 -0700 (PDT)
DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 63C3A20E97C1
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com;
s=default; t=1712250914;
bh=rD+L0VBEA4ijIJdqdd449HN9OEIpZijzzM7uh0U3AQI=;
h=From:To:Cc:Subject:Date:In-Reply-To:References:From;
b=qrnREoKVqff0DtjBVN7ryRKKIj3Yj3IKzzmZmLHi1J/fhN9E50nqWjQHZXeexfm3C
1XVUskKQaMPawK8I688aQVpFBysb1rp5mv9tjftuVcJxnhyKMtWSP8U4fjF3hWtOJY
Tw9KaNbCNxhTIH3rCvsILpUKmCXHeotaQCvaU6ME=
From: Tyler Retzlaff <roretzla@linux.microsoft.com>
To: dev@dpdk.org
Cc: Bruce Richardson <bruce.richardson@intel.com>,
Stephen Hemminger <stephen@networkplumber.org>,
Thomas Monjalon <thomas@monjalon.net>,
=?UTF-8?q?Morten=20Br=C3=B8rup?= <mb@smartsharesystems.com>,
Tyler Retzlaff <roretzla@linux.microsoft.com>
Subject: [PATCH 3/4] vhost: use alloca instead of vla sizeof
Date: Thu, 4 Apr 2024 10:15:12 -0700
Message-Id: <1712250913-1977-4-git-send-email-roretzla@linux.microsoft.com>
X-Mailer: git-send-email 1.8.3.1
In-Reply-To: <1712250913-1977-1-git-send-email-roretzla@linux.microsoft.com>
References: <20231107193220.GA15232@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net>
<1712250913-1977-1-git-send-email-roretzla@linux.microsoft.com>
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://mails.dpdk.org/options/dev>,
<mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://mails.dpdk.org/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://mails.dpdk.org/listinfo/dev>,
<mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
RFC sample illustrating conversion of VLA to alloca() where
sizeof(array) was in use.
Signed-off-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
---
lib/vhost/socket.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/lib/vhost/socket.c b/lib/vhost/socket.c
index 96b3ab5..cedcfb2 100644
--- a/lib/vhost/socket.c
+++ b/lib/vhost/socket.c
@@ -110,7 +110,8 @@ struct vhost_user {
{
struct iovec iov;
struct msghdr msgh;
- char control[CMSG_SPACE(max_fds * sizeof(int))];
+ const size_t control_sz = sizeof(char) * CMSG_SPACE(max_fds * sizeof(int));
+ char *control = alloca(control_sz);
struct cmsghdr *cmsg;
int got_fds = 0;
int ret;
@@ -124,7 +125,7 @@ struct vhost_user {
msgh.msg_iov = &iov;
msgh.msg_iovlen = 1;
msgh.msg_control = control;
- msgh.msg_controllen = sizeof(control);
+ msgh.msg_controllen = control_sz;
ret = recvmsg(sockfd, &msgh, 0);
if (ret <= 0) {
--
1.8.3.1