From: Aram Sargsyan <aram@isc.org>
Date: Wed, 11 Sep 2024 15:58:11 +0000 (+0000)
Subject: Fix data race in offloaded dns_message_checksig()
X-Git-Tag: v9.21.2~42^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=35ef25e5ea442eb0cb3731b1f2a0546394a2e97a;p=thirdparty%2Fbind9.git

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.
---

diff --git a/lib/dns/message.c b/lib/dns/message.c
index 6f1938a3373..6565cbf09d0 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);