From b3834bbf248f3376ada8fc44166cba38c8ad4bcf Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@sudo.ws>
Date: Thu, 17 Nov 2022 08:10:35 -0700
Subject: [PATCH] sudo_passwd_cleanup: Set auth->data to NULL after freeing.
 GitHub issue #201

---
 plugins/sudoers/auth/passwd.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/plugins/sudoers/auth/passwd.c b/plugins/sudoers/auth/passwd.c
index 89da96ff6..6967e4fff 100644
--- a/plugins/sudoers/auth/passwd.c
+++ b/plugins/sudoers/auth/passwd.c
@@ -117,11 +117,14 @@ sudo_passwd_verify(struct passwd *pw, const char *pass, sudo_auth *auth, struct
 int
 sudo_passwd_cleanup(struct passwd *pw, sudo_auth *auth, bool force)
 {
-    char *pw_epasswd = auth->data;
     debug_decl(sudo_passwd_cleanup, SUDOERS_DEBUG_AUTH);
 
-    if (pw_epasswd != NULL)
-	freezero(pw_epasswd, strlen(pw_epasswd));
+    if (auth->data != NULL) {
+	/* Zero out encrypted password before freeing. */
+	size_t len = strlen((char *)auth->data);
+	freezero(auth->data, len);
+	auth->data = NULL;
+    }
 
     debug_return_int(AUTH_SUCCESS);
 }
-- 
2.27.0

