[ovs-dev] ipf.c: Fix userspace datapath crash caused by IP fragments

[王亮 Liang Wang]

From d5c454bc9c68a6b2b40a2301a21f7337d6086d4c Mon Sep 17 00:00:00 2001

From: Wang Liang <wangliangrt at didiglobal.com>

Date: Mon, 12 Apr 2021 18:24:21 +0800

Subject: [PATCH] Fix userspace datapath crash caused by IP fragments


The ovs userspace datapath will crash on openflow packet-out message

with IP packet largger than MTU. This patch will fix the problem.

When pre-processing IP fragments, clone the packet if it has 'dnsteal' flag set.


Signed-off-by: Wang Liang <wangliangrt at didiglobal.com>

---

 lib/ipf.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)


diff --git a/lib/ipf.c b/lib/ipf.c

index c20bcc0b3..43f81706c 100644

--- a/lib/ipf.c

+++ b/lib/ipf.c

@@ -811,7 +811,7 @@ ipf_process_frag(struct ipf *ipf, struct ipf_list *ipf_list,

              * recommend not setting the mempool number of buffers too low

              * and also clamp the number of fragments. */

             struct ipf_frag *frag = &ipf_list->frag_list[last_inuse_idx + 1];

-            frag->pkt = pkt;

+            frag->pkt = dnsteal ? dp_packet_clone(pkt) : pkt;

             frag->start_data_byte = start_data_byte;

             frag->end_data_byte = end_data_byte;

             frag->dnsteal = dnsteal;

--

2.27.0