From ac132852147ad303a938dda318970dd1bbdfda4e Mon Sep 17 00:00:00 2001 From: Kumar Thangavel Date: Mon, 22 Nov 2021 22:08:18 +0530 Subject: [PATCH] net/ncsi : Add payload to be 32-bit aligned to fix dropped packets 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. Fixes: fb4ee67529ff ("net/ncsi: Add NCSI OEM command support") Signed-off-by: Kumar Thangavel Acked-by: Samuel Mendoza-Jonas Reviewed-by: Paul Menzel Signed-off-by: David S. Miller --- net/ncsi/ncsi-cmd.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/net/ncsi/ncsi-cmd.c b/net/ncsi/ncsi-cmd.c index ba9ae482141b..dda8b76b7798 100644 --- a/net/ncsi/ncsi-cmd.c +++ b/net/ncsi/ncsi-cmd.c @@ -18,6 +18,8 @@ #include "internal.h" #include "ncsi-pkt.h" +static const int padding_bytes = 26; + u32 ncsi_calculate_checksum(unsigned char *data, int len) { u32 checksum = 0; @@ -213,12 +215,17 @@ static int ncsi_cmd_handler_oem(struct sk_buff *skb, { struct ncsi_cmd_oem_pkt *cmd; unsigned int len; + int payload; + /* NC-SI spec DSP_0222_1.2.0, section 8.2.2.2 + * 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 + */ + payload = ALIGN(nca->payload, 4); len = sizeof(struct ncsi_cmd_pkt_hdr) + 4; - if (nca->payload < 26) - len += 26; - else - len += nca->payload; + len += max(payload, padding_bytes); cmd = skb_put_zero(skb, len); memcpy(&cmd->mfr_id, nca->data, nca->payload); @@ -272,6 +279,7 @@ static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca) struct net_device *dev = nd->dev; int hlen = LL_RESERVED_SPACE(dev); int tlen = dev->needed_tailroom; + int payload; int len = hlen + tlen; struct sk_buff *skb; struct ncsi_request *nr; @@ -281,14 +289,14 @@ static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca) return NULL; /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum. + * Payload needs padding so that the checksum field following payload is + * aligned to 32-bit boundary. * The packet needs padding if its payload is less than 26 bytes to * meet 64 bytes minimal ethernet frame length. */ len += sizeof(struct ncsi_cmd_pkt_hdr) + 4; - if (nca->payload < 26) - len += 26; - else - len += nca->payload; + payload = ALIGN(nca->payload, 4); + len += max(payload, padding_bytes); /* Allocate skb */ skb = alloc_skb(len, GFP_ATOMIC);