From 0dcf0c0aeefd2bc1023c9fe7ab0f1b6bc993c360 Mon Sep 17 00:00:00 2001 From: Markus Carlstedt Date: Fri, 11 Dec 2020 17:35:10 +0800 Subject: [PATCH] net: checksum: Skip fragmented IP packets To calculate the TCP/UDP checksum we need the whole datagram. Unless the hardware has some logic to collect all fragments before sending the whole datagram first, it can only be done by the network stack, which is normally the case for the NICs we have seen so far. Skip these fragmented IP packets to avoid checksum corruption. Signed-off-by: Markus Carlstedt Signed-off-by: Bin Meng Signed-off-by: Jason Wang --- net/checksum.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/checksum.c b/net/checksum.c index aaa4000238..5cb8b2c368 100644 --- a/net/checksum.c +++ b/net/checksum.c @@ -106,6 +106,10 @@ void net_checksum_calculate(uint8_t *data, int length) return; /* not IPv4 */ } + if (IP4_IS_FRAGMENT(ip)) { + return; /* a fragmented IP packet */ + } + ip_len = lduw_be_p(&ip->ip_len); /* Last, check that we have enough data for the all IP frame */