From 648fc1e369fc05fb9200a42c7938912236b2a318 Mon Sep 17 00:00:00 2001
From: Stanislav Malyshev <stas@php.net>
Date: Sun, 11 Nov 2018 10:04:01 -0800
Subject: [PATCH] Fix #77020: null pointer dereference in imap_mail

If an empty $message is passed to imap_mail(), we must not set message
to NULL, since _php_imap_mail() is not supposed to handle NULL pointers
(opposed to pointers to NUL).

(cherry picked from commit 7edc639b9ff1c3576773d79d016abbeed1f93846)
---
 ext/imap/php_imap.c          |  1 -
 ext/imap/tests/bug77020.phpt | 15 +++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)
 create mode 100644 ext/imap/tests/bug77020.phpt

diff --git a/ext/imap/php_imap.c b/ext/imap/php_imap.c
index 9e626a4..01d1a5f 100644
--- a/ext/imap/php_imap.c
+++ b/ext/imap/php_imap.c
@@ -4116,7 +4116,6 @@ PHP_FUNCTION(imap_mail)
 	if (!ZSTR_LEN(message)) {
 		/* this is not really an error, so it is allowed. */
 		php_error_docref(NULL, E_WARNING, "No message string in mail command");
-		message = NULL;
 	}
 
 	if (_php_imap_mail(ZSTR_VAL(to), ZSTR_VAL(subject), ZSTR_VAL(message), headers?ZSTR_VAL(headers):NULL, cc?ZSTR_VAL(cc):NULL,
diff --git a/ext/imap/tests/bug77020.phpt b/ext/imap/tests/bug77020.phpt
new file mode 100644
index 0000000..8a65232
--- /dev/null
+++ b/ext/imap/tests/bug77020.phpt
@@ -0,0 +1,15 @@
+--TEST--
+Bug #77020 (null pointer dereference in imap_mail)
+--SKIPIF--
+<?php
+if (!extension_loaded('imap')) die('skip imap extension not available');
+?>
+--FILE--
+<?php
+imap_mail('1', 1, NULL);
+?>
+===DONE===
+--EXPECTF--
+Warning: imap_mail(): No message string in mail command in %s on line %d
+%s
+===DONE===
-- 
2.1.4