Fix desychronisation with kTLS:

https://gitlab.com/gnutls/gnutls/-/issues/1470

gnutls-3.8.0-ktls-Do-not-return-GNUTLS_E_INTERRUPTED-AGAIN-from-s.patch

@@ -0,0 +1,52 @@
+From 21c386860f1973344872eec4e4dd68644b1b48aa Mon Sep 17 00:00:00 2001
+From: "Richard W.M. Jones" <rjones@redhat.com>
+Date: Fri, 10 Mar 2023 11:15:19 +0000
+Subject: [PATCH] ktls: Do not return GNUTLS_E_INTERRUPTED/AGAIN from short
+ writes
+
+If sendmsg returns a short write, we end up going around the loop with
+data_to_send being smaller.  However if sendmsg then returns -EAGAIN
+or -EINTR then we return an error.  But we have "forgotten" that we
+already sent some data.
+
+This causes the caller to retry gnutls_record_send with the full
+buffer (ie. with a buffer that has already been partially sent),
+causing desynchronization.
+
+Instead check if we sent some data in this case and return the number
+of bytes sent.
+
+Fixes: https://gitlab.com/gnutls/gnutls/-/issues/1470
+Thanks: Dan Berrange for suggesting a fix
+Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
+---
+ lib/system/ktls.c | 12 ++++++++++--
+ 1 file changed, 10 insertions(+), 2 deletions(-)
+
+diff --git a/lib/system/ktls.c b/lib/system/ktls.c
+index fd57a9c30..bb59fab7c 100644
+--- a/lib/system/ktls.c
++++ b/lib/system/ktls.c
+@@ -604,9 +604,17 @@ int _gnutls_ktls_send_control_msg(gnutls_session_t session,
+ 		if (ret == -1) {
+ 			switch (errno) {
+ 			case EINTR:
+-				return GNUTLS_E_INTERRUPTED;
++				if (data_to_send < data_size) {
++					return data_size - data_to_send;
++				} else {
++					return GNUTLS_E_INTERRUPTED;
++				}
+ 			case EAGAIN:
+-				return GNUTLS_E_AGAIN;
++				if (data_to_send < data_size) {
++					return data_size - data_to_send;
++				} else {
++					return GNUTLS_E_AGAIN;
++				}
+ 			default:
+ 				return GNUTLS_E_PUSH_ERROR;
+ 			}
+-- 
+2.39.2
+

gnutls.spec

@@ -29,6 +29,10 @@ Patch: gnutls-3.7.8-ktls_disable_keyupdate_test.patch
 # follow https://gitlab.com/gnutls/gnutls/-/issues/1443
 Patch: gnutls-3.7.8-ktls_skip_tls12_chachapoly_test.patch
 
+# Fix desychronisation with kTLS:
+# https://gitlab.com/gnutls/gnutls/-/issues/1470
+Patch: gnutls-3.8.0-ktls-Do-not-return-GNUTLS_E_INTERRUPTED-AGAIN-from-s.patch
+
 %bcond_without bootstrap
 %bcond_without dane
 %bcond_without fips