!37 ssl: do not trigger EOF if some data had been successfully read

From: @tong_1001 
Reviewed-by: @hubin95, @xiezhipeng1 
Signed-off-by: @xiezhipeng1

backport-ssl-do-not-trigger-EOF-if-some-data-had-been-successf.patch

@@ -0,0 +1,44 @@
+From 7652cf4068f77905a56b9165455ec7e90917ec31 Mon Sep 17 00:00:00 2001
+From: Azat Khuzhin <azat@libevent.org>
+Date: Sun, 14 May 2023 16:53:13 +0200
+Subject: [PATCH] ssl: do not triger EOF if some data had been successfully 
+read
+
+Reference:https://github.com/libevent/libevent/commit/ef51444f439b922c8fb00c7ef3f8482b6400b6ea
+https://github.com/libevent/libevent/commit/49a7ae4c5668ebad7b6c4618664224c1a0bc5079
+https://github.com/libevent/libevent/commit/7652cf4068f77905a56b9165455ec7e90917ec31
+
+Previously in case when evbuffer_reserve_space() returns > 1, but
+it was able to read only 1 IO vector, it will try to read the next one,
+got 0 (EOF for mbedTLS or SSL_ERROR_ZERO_RETURN for OpenSSL) and will
+trigger EOF, while instead, it should trigger EV_READ w/o EOF and only
+after EOF.
+---
+ bufferevent_openssl.c | 11 +++++++++++
+ 1 file changed, 11 insertions(+)
+
+diff --git a/bufferevent_openssl.c b/bufferevent_openssl.c
+index b51b834..8b4b655 100644
+--- a/bufferevent_openssl.c
++++ b/bufferevent_openssl.c
+@@ -616,6 +616,17 @@ do_read(struct bufferevent_openssl *bev_ssl, int n_to_read) {
+ 		} else {
+ 			int err = SSL_get_error(bev_ssl->ssl, r);
+ 			print_err(err);
++			/* NOTE: we ignore the error in case of some progress was done,
++			 * because currently we do not send close_notify, and this will
++			 * lead to error from SSL_read() (it will return 0, and
++			 * SSL_get_error() will return SSL_ERROR_SSL), and this is because
++			 * of lack of close_notify
++			 *
++			 * But AFAICS some code uses it the same way (i.e. nginx) */
++			if (result & OP_MADE_PROGRESS) {
++				/* Process existing data */
++				break;
++			}
+ 			switch (err) {
+ 			case SSL_ERROR_WANT_READ:
+ 				/* Can't read until underlying has more data. */
+-- 
+2.27.0
+

libevent.spec

@@ -1,6 +1,6 @@
 Name:           libevent
 Version:        2.1.12
-Release:        7
+Release:        8
 Summary:        An event notification library
 
 License:        BSD
@@ -18,6 +18,7 @@ Patch2: add-testcases-for-event.c-apis.patch
 # issue is fixed.
 # https://github.com/transmission/transmission/issues/1437
 Patch3: 0001-Revert-Fix-checking-return-value-of-the-evdns_base_r.patch
+Patch6000: backport-ssl-do-not-trigger-EOF-if-some-data-had-been-successf.patch 
 
 %description
 Libevent additionally provides a sophisticated framework for buffered network IO, with support for sockets,
@@ -78,6 +79,9 @@ rm -f %{buildroot}%{_libdir}/*.la
 
 
 %changelog
+* Sat Jul 29 2023 shixuantong <shixuantong1@huawei.com> - 2.1.12-8
+- ssl: do not trigger EOF if some data had been successfully read
+
 * Thu Feb 16 2023 dillon chen <dillon.chen@gmail.com> - 2.1.12-7
 - close make check