Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Ben Wei <benwei@fb.com>
To:     Ben Wei <benwei@fb.com>, David Miller <davem@davemloft.net>,
        "sam@mendozajonas.com" <sam@mendozajonas.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "openbmc@lists.ozlabs.org" <openbmc@lists.ozlabs.org>
CC:     Ben Wei <benwei@fb.com>
Subject: [PATCH net-next] net/ncsi: support unaligned payload size in NC-SI
 cmd handler
Thread-Topic: [PATCH net-next] net/ncsi: support unaligned payload size in
 NC-SI cmd handler
Thread-Index: AdVhOKsnD7LLLBrzTcm5Yllqe1NFWA==
Date:   Mon, 2 Sep 2019 02:46:52 +0000
Message-ID: <CH2PR15MB368619179F403EAE47FD61F7A3BE0@CH2PR15MB3686.namprd15.prod.outlook.com>
Accept-Language: en-US
Content-Language: en-US
received-spf: None (protection.outlook.com: fb.com does not designate
 permitted sender hosts)
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-Network-Message-Id: bd3c89c4-5b02-4256-bf1c-08d72f4fcf5e
X-MS-Exchange-CrossTenant-originalarrivaltime: 02 Sep 2019 02:46:52.2650
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: UqJ5y4lANzTqIxV1oP8uZoAdpf3p2HPpNhaiA39vxQXeEbT7wmpInIPguXzxNFTE
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR15MB3621
X-OriginatorOrg: fb.com
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.70,1.0.8
 definitions=2019-09-02_01:2019-08-29,2019-09-02 signatures=0
X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 phishscore=0
 malwarescore=0 lowpriorityscore=0 clxscore=1015 mlxscore=0 spamscore=0
 suspectscore=0 adultscore=0 bulkscore=0 mlxlogscore=909 priorityscore=1501
 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1
 engine=8.12.0-1906280000 definitions=main-1909020030
X-FB-Internal: deliver
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Update NC-SI command handler (both standard and OEM) to take into
account of payload paddings in allocating skb (in case of payload
size is not 32-bit aligned).

The checksum field follows payload field, without taking payload
padding into account can cause checksum being truncated, leading to
dropped packets.

Signed-off-by: Ben Wei <benwei@fb.com>
---
 net/ncsi/ncsi-cmd.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/net/ncsi/ncsi-cmd.c b/net/ncsi/ncsi-cmd.c
index 0187e65176c0..42636ed3cf3a 100644
--- a/net/ncsi/ncsi-cmd.c
+++ b/net/ncsi/ncsi-cmd.c
@@ -213,17 +213,22 @@ static int ncsi_cmd_handler_oem(struct sk_buff *skb,
 {
 	struct ncsi_cmd_oem_pkt *cmd;
 	unsigned int len;
+	/* NC-SI spec requires payload to be padded with 0
+	 * to 32-bit boundary before the checksum field.
+	 * Ensure the padding bytes are accounted for in
+	 * skb allocation
+	 */
+	unsigned short payload =3D ALIGN(nca->payload, 4);
=20
 	len =3D sizeof(struct ncsi_cmd_pkt_hdr) + 4;
-	if (nca->payload < 26)
+	if (payload < 26)
 		len +=3D 26;
 	else
-		len +=3D nca->payload;
+		len +=3D payload;
=20
 	cmd =3D skb_put_zero(skb, len);
 	memcpy(&cmd->mfr_id, nca->data, nca->payload);
 	ncsi_cmd_build_header(&cmd->cmd.common, nca);
-
 	return 0;
 }
=20
@@ -272,6 +277,7 @@ static struct ncsi_request *ncsi_alloc_command(struct n=
csi_cmd_arg *nca)
 	struct net_device *dev =3D nd->dev;
 	int hlen =3D LL_RESERVED_SPACE(dev);
 	int tlen =3D dev->needed_tailroom;
+	int payload;
 	int len =3D hlen + tlen;
 	struct sk_buff *skb;
 	struct ncsi_request *nr;
@@ -281,14 +287,17 @@ static struct ncsi_request *ncsi_alloc_command(struct=
 ncsi_cmd_arg *nca)
 		return NULL;
=20
 	/* NCSI command packet has 16-bytes header, payload, 4 bytes checksum.
+	 * Payload needs padding so that the checksum field follwoing payload is
+	 * aligned to 32bit boundary.
 	 * The packet needs padding if its payload is less than 26 bytes to
 	 * meet 64 bytes minimal ethernet frame length.
 	 */
 	len +=3D sizeof(struct ncsi_cmd_pkt_hdr) + 4;
-	if (nca->payload < 26)
+	payload =3D ALIGN(nca->payload, 4);
+	if (payload < 26)
 		len +=3D 26;
 	else
-		len +=3D nca->payload;
+		len +=3D payload;
=20
 	/* Allocate skb */
 	skb =3D alloc_skb(len, GFP_ATOMIC);
--=20
2.17.1