Exclude CRC fields, the minimum Ethernet packet length is 60 bytes. When the actual packet length is less than 60 bytes, padding is added to the tail. When GRO is performed on a packet containing a padding field, mbuf->pkt_len is the one that contains the padding field, which leads to the error of thinking of the padding field as the actual content of the packet. We need to trim away this extra padding field during GRO processing.
Fixes: 0d2cbe59b719 ("lib/gro: support TCP/IPv4") Cc: sta...@dpdk.org Signed-off-by: Jun Qiu <jun....@jaguarmicro.com> --- lib/gro/gro_tcp4.c | 7 ++++++- lib/gro/gro_udp4.c | 4 ++++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/lib/gro/gro_tcp4.c b/lib/gro/gro_tcp4.c index 7849a2bd1d..0110db5748 100644 --- a/lib/gro/gro_tcp4.c +++ b/lib/gro/gro_tcp4.c @@ -198,7 +198,7 @@ gro_tcp4_reassemble(struct rte_mbuf *pkt, struct rte_tcp_hdr *tcp_hdr; uint32_t sent_seq; int32_t tcp_dl; - uint16_t ip_id, hdr_len, frag_off; + uint16_t ip_id, hdr_len, frag_off, ip_tlen; uint8_t is_atomic; struct tcp4_flow_key key; @@ -233,6 +233,11 @@ gro_tcp4_reassemble(struct rte_mbuf *pkt, if (tcp_dl <= 0) return -1; + /* trim the tail padding bytes */ + ip_tlen = rte_be_to_cpu_16(ipv4_hdr->total_length); + if (pkt->pkt_len > (uint32_t)(ip_tlen + pkt->l2_len)) + rte_pktmbuf_trim(pkt, pkt->pkt_len - ip_tlen - pkt->l2_len); + /* * Save IPv4 ID for the packet whose DF bit is 0. For the packet * whose DF bit is 1, IPv4 ID is ignored. diff --git a/lib/gro/gro_udp4.c b/lib/gro/gro_udp4.c index dd71135ada..839f9748b7 100644 --- a/lib/gro/gro_udp4.c +++ b/lib/gro/gro_udp4.c @@ -231,6 +231,10 @@ gro_udp4_reassemble(struct rte_mbuf *pkt, if (ip_dl <= pkt->l3_len) return -1; + /* trim the tail padding bytes */ + if (pkt->pkt_len > (uint32_t)(ip_dl + pkt->l2_len)) + rte_pktmbuf_trim(pkt, pkt->pkt_len - ip_dl - pkt->l2_len); + ip_dl -= pkt->l3_len; ip_id = rte_be_to_cpu_16(ipv4_hdr->packet_id); frag_offset = rte_be_to_cpu_16(ipv4_hdr->fragment_offset); -- 2.25.1