From be754f6435936e78dafe0ebb9d1e9d52c3bde842 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Sat, 12 Jun 2021 09:37:34 -0500 Subject: [PATCH] net: qualcomm: rmnet: trailer value is a checksum The csum_value field in the rmnet_map_dl_csum_trailer structure is a "real" Internet checksum. It is a 16 bit value, in big endian format, which represents an inverted ones' complement sum over pairs of bytes. Make that clear by changing its type to __sum16. This makes a typecast in rmnet_map_ipv4_dl_csum_trailer() and another in rmnet_map_ipv6_dl_csum_trailer() unnecessary. Signed-off-by: Alex Elder Signed-off-by: David S. Miller --- drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c | 5 ++--- include/linux/if_rmnet.h | 2 +- 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c index 033b8ad..610c8b5 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c @@ -87,7 +87,7 @@ rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb, * header checksum value; it is already accounted for in the * checksum value found in the trailer. */ - ip_payload_csum = (__force __sum16)~csum_trailer->csum_value; + ip_payload_csum = ~csum_trailer->csum_value; pseudo_csum = ~csum_tcpudp_magic(ip4h->saddr, ip4h->daddr, ntohs(ip4h->tot_len) - ip4h->ihl * 4, @@ -132,8 +132,7 @@ rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, * checksum computed over the pseudo header. */ ip_header_csum = (__force __be16)ip_fast_csum(ip6h, sizeof(*ip6h) / 4); - ip6_payload_csum = ~csum16_sub((__force __sum16)csum_trailer->csum_value, - ip_header_csum); + ip6_payload_csum = ~csum16_sub(csum_trailer->csum_value, ip_header_csum); length = (ip6h->nexthdr == IPPROTO_UDP) ? ntohs(((struct udphdr *)txporthdr)->len) : diff --git a/include/linux/if_rmnet.h b/include/linux/if_rmnet.h index be17610a..10e7521 100644 --- a/include/linux/if_rmnet.h +++ b/include/linux/if_rmnet.h @@ -25,7 +25,7 @@ struct rmnet_map_dl_csum_trailer { u8 flags; /* MAP_CSUM_DL_VALID_FLAG */ __be16 csum_start_offset; __be16 csum_length; - __be16 csum_value; + __sum16 csum_value; } __aligned(1); /* rmnet_map_dl_csum_trailer flags field: -- 2.7.4