Skip to contentSkip to conversation

TCP data length is incorrectly calculated in the gro_tcp4_reassemble function.

PATCH In review jiangheng (G) 2 participants 3 messages Sep 28, 2022 – Nov 1, 2023

lore
Share & tools
lore

jiangheng (G)

author
#0 lore raw

PATCH 1/1 TCP data length is incorrectly calculated in the gro_tcp4_reassemble function.

Hello:
In gro_tcp4_reassemble function, tcp data len is calculated:
tcp_dl = pkt->pkt_len - hdr_len;
https://github.com/DPDK/dpdk/blob/v22.07/lib/gro/gro_tcp4.c#L232

if packets < 60 bytes, pkt_len will contain padding bytes, tcp_dl is incorrectly calculated. this will result the wrong data length after gro.

lib/gro/gro_tcp4.c +1 -1
index 7498c66141..cbba9fed5e 100644
@@ -229,7 +229,7 @@ gro_tcp4_reassemble(struct rte_mbuf *pkt,
         * Don't process the packet whose payload length is less than or
         * equal to 0.
         */
-       tcp_dl = pkt->pkt_len - hdr_len;
+       tcp_dl = rte_be_to_cpu_16(ipv4_hdr->total_length) - hdr_len;
        if (tcp_dl <= 0)
                return -1;
#1 lore raw
Quoted 12 lines · On Wed, 28 Sep 2022 14:10:52 +0000 "jiangheng (G)" <[email protected]>…

Hello:
In gro_tcp4_reassemble function, tcp data len is calculated:
tcp_dl = pkt->pkt_len - hdr_len;
https://github.com/DPDK/dpdk/blob/v22.07/lib/gro/gro_tcp4.c#L232

if packets < 60 bytes, pkt_len will contain padding bytes, tcp_dl is incorrectly calculated. this will result the wrong data length after gro.

lib/gro/gro_tcp4.c +0 -0
index 7498c66141..cbba9fed5e 100644

lib/gro/gro_tcp4.c gro_tcp4_reassemble(struct rte_mbuf *pkt, · line 234

Quoted 7 lines
lib/gro/gro_tcp4.c +1 -1
@@ -229,7 +229,7 @@ gro_tcp4_reassemble(struct rte_mbuf *pkt,
         * Don't process the packet whose payload length is less than or
         * equal to 0.
         */
-       tcp_dl = pkt->pkt_len - hdr_len;
+       tcp_dl = rte_be_to_cpu_16(ipv4_hdr->total_length) - hdr_len;
        if (tcp_dl <= 0)
                return -1;

Yes, this patch looks correct. But it is not formatted correctly as reported by checkpatch.
1. DPDK uses tab character for indent
2. Commit messages are supposed to be wrapped and not long lines

Could you resubmit?

author
#2 lore raw

Hi:
This issue has been fixed:
https://github.com/DPDK/dpdk/commit/b8a55871d5af6f5b8694b1cb5eacbc629734e403
https://github.com/DPDK/dpdk/commit/72f51b097a71fb9bdea13bdd254ff620b34c852e

-----邮件原件-----
发件人: Stephen Hemminger <[email protected]>
发送时间: 2023年11月1日 2:56
收件人: jiangheng (G) <[email protected]>
抄送: [email protected]
主题: Re: [PATCH] TCP data length is incorrectly calculated in the gro_tcp4_reassemble function.

Quoted 12 lines · On Wed, 28 Sep 2022 14:10:52 +0000 "jiangheng (G)" <[email protected]>…

Hello:
In gro_tcp4_reassemble function, tcp data len is calculated:
tcp_dl = pkt->pkt_len - hdr_len;
https://github.com/DPDK/dpdk/blob/v22.07/lib/gro/gro_tcp4.c#L232

if packets < 60 bytes, pkt_len will contain padding bytes, tcp_dl is incorrectly calculated. this will result the wrong data length after gro.

lib/gro/gro_tcp4.c index renamed from lib/gro/gro_tcp4.c +0 -0

7498c66141..cbba9fed5e 100644

lib/gro/gro_tcp4.c gro_tcp4_reassemble(struct rte_mbuf *pkt, · line 234

Quoted 7 lines
lib/gro/gro_tcp4.c +1 -1
@@ -229,7 +229,7 @@ gro_tcp4_reassemble(struct rte_mbuf *pkt,
         * Don't process the packet whose payload length is less than or
         * equal to 0.
         */
-       tcp_dl = pkt->pkt_len - hdr_len;
+       tcp_dl = rte_be_to_cpu_16(ipv4_hdr->total_length) - hdr_len;
        if (tcp_dl <= 0)
                return -1;

Yes, this patch looks correct. But it is not formatted correctly as reported by checkpatch.
1. DPDK uses tab character for indent
2. Commit messages are supposed to be wrapped and not long lines

Could you resubmit?