From 65fced42b96ef2617057a15c6ded3060be99678a Mon Sep 17 00:00:00 2001
From: Aram Sargsyan <aram@isc.org>
Date: Wed, 11 Sep 2024 15:58:11 +0000
Subject: [PATCH] Fix data race in offloaded dns_message_checksig()

When verifying a message in an offloaded thread there is a race with
the worker thread which writes to the same buffer. Clone the message
buffer before offloading.

(cherry picked from commit 35ef25e5ea442eb0cb3731b1f2a0546394a2e97a)
---
 lib/dns/message.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/dns/message.c b/lib/dns/message.c
index c00d54bffd..7c642553fd 100644
--- a/lib/dns/message.c
+++ b/lib/dns/message.c
@@ -3254,6 +3254,7 @@ dns_message_checksig_async(dns_message_t *msg, dns_view_t *view,
 	dns_message_attach(msg, &chsigctx->msg);
 	dns_view_attach(view, &chsigctx->view);
 
+	dns_message_clonebuffer(msg);
 	isc_work_enqueue(loop, checksig_run, checksig_cb, chsigctx);
 
 	return (DNS_R_WAIT);