net: sparx5: fix handling uneven length packets in manual extraction

[ Upstream commit 7498a45 ]

Packets that are not of length divisible by 4 (e.g. 77, 78, 79) would
have the checksum included up to next multiple of 4 (a 77 bytes packet
would have 3 bytes of ethernet checksum included). The check for the
value expects it in host (Little) endian.

Fixes: f3cad26 ("net: sparx5: add hostmode with phylink support")
Signed-off-by: Casper Andersson <casper.casan@gmail.com>
Reviewed-by: Steen Hegelund <Steen.Hegelund@microchip.com>
Link: https://lore.kernel.org/r/20220825084955.684637-1-casper.casan@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/ethernet/microchip/sparx5/sparx5_packet.c

@@ -107,6 +107,8 @@ static void sparx5_xtr_grp(struct sparx5 *sparx5, u8 grp, bool byte_swap)
 			/* This assumes STATUS_WORD_POS == 1, Status
 			 * just after last data
 			 */
+			if (!byte_swap)
+				val = ntohl((__force __be32)val);
 			byte_cnt -= (4 - XTR_VALID_BYTES(val));
 			eof_flag = true;
 			break;