From cfce1bd2291503233564a5299172cb04d5d652e4 Mon Sep 17 00:00:00 2001
From: "Christoph M. Becker" <cmbecker69@gmx.de>
Date: Thu, 26 Mar 2020 15:48:56 +0100
Subject: [PATCH 1/2] Fix #79413: session_create_id() fails for active sessions

The comment on `PS_VALIDATE_SID_FUNC(files)` is very clear that the
function is supposed to return `SUCCESS` if the session already exists.
So to detect a collision, we have to check for `SUCCESS`, not
`FAILURE`.
---
 ext/session/session.c           |  2 +-
 ext/session/tests/bug79091.phpt |  2 +-
 ext/session/tests/bug79413.phpt | 15 +++++++++++++++
 3 files changed, 17 insertions(+), 2 deletions(-)
 create mode 100644 ext/session/tests/bug79413.phpt

diff --git a/ext/session/session.c b/ext/session/session.c
index 078b3f0b3ce85..ab114c0c1a0d8 100644
--- a/ext/session/session.c
+++ b/ext/session/session.c
@@ -2285,7 +2285,7 @@ static PHP_FUNCTION(session_create_id)
 				break;
 			} else {
 				/* Detect collision and retry */
-				if (PS(mod)->s_validate_sid(&PS(mod_data), new_id) == FAILURE) {
+				if (PS(mod)->s_validate_sid(&PS(mod_data), new_id) == SUCCESS) {
 					zend_string_release_ex(new_id, 0);
                     new_id = NULL;
 					continue;
diff --git a/ext/session/tests/bug79091.phpt b/ext/session/tests/bug79091.phpt
index 1d14427159aca..4d60e698729ec 100644
--- a/ext/session/tests/bug79091.phpt
+++ b/ext/session/tests/bug79091.phpt
@@ -50,7 +50,7 @@ class MySessionHandler implements SessionHandlerInterface, SessionIdInterface, S
 
     public function validateId($key)
     {
-        return false;
+        return true;
     }
 }
 
diff --git a/ext/session/tests/bug79413.phpt b/ext/session/tests/bug79413.phpt
new file mode 100644
index 0000000000000..756b29f6ea6a3
--- /dev/null
+++ b/ext/session/tests/bug79413.phpt
@@ -0,0 +1,15 @@
+--TEST--
+Bug #79413 (session_create_id() fails for active sessions)
+--SKIPIF--
+<?php
+if (!extension_loaded('session')) die('skip session extension not available');
+?>
+--FILE--
+<?php
+session_start();
+$old = session_id();
+$new = session_create_id();
+var_dump($new !== $old);
+?>
+--EXPECT--
+bool(true)

From 148d7a33ab3357ea0c1d198bba2418670f09a2b1 Mon Sep 17 00:00:00 2001
From: "Christoph M. Becker" <cmbecker69@gmx.de>
Date: Thu, 26 Mar 2020 19:01:33 +0100
Subject: [PATCH 2/2] Fix wrong condition in session_regenerate_id() as well

If the new SID is invalid, i.e. no such session exists yet, there is no
need to create a new SID.  On the other hand, if such session already
exists, we have to create a new SID to satisfy strict mode (actually,
we would have to repeat this until we find an invalid SID).
---
 ext/session/session.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ext/session/session.c b/ext/session/session.c
index ab114c0c1a0d8..52b9da31808de 100644
--- a/ext/session/session.c
+++ b/ext/session/session.c
@@ -2223,7 +2223,7 @@ static PHP_FUNCTION(session_regenerate_id)
 		RETURN_FALSE;
 	}
 	if (PS(use_strict_mode) && PS(mod)->s_validate_sid &&
-		PS(mod)->s_validate_sid(&PS(mod_data), PS(id)) == FAILURE) {
+		PS(mod)->s_validate_sid(&PS(mod_data), PS(id)) == SUCCESS) {
 		zend_string_release_ex(PS(id), 0);
 		PS(id) = PS(mod)->s_create_sid(&PS(mod_data));
 		if (!PS(id)) {