sudo: backport fix for CVE-2022-43995

(From OE-Core rev: a41a5f310246dcd9dbdb4537d59bc0579c3b1052)

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
This commit is contained in:
Ross Burton
2022-11-07 18:02:05 +00:00
committed by Richard Purdie
parent c689d5d4e3
commit 63e80a0233
2 changed files with 55 additions and 0 deletions

View File

@@ -0,0 +1,54 @@
CVE: CVE-2022-43995
Upstream-Status: Backport
Signed-off-by: Ross Burton <ross.burton@arm.com>
From bd209b9f16fcd1270c13db27ae3329c677d48050 Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@sudo.ws>
Date: Fri, 28 Oct 2022 07:29:55 -0600
Subject: [PATCH] Fix CVE-2022-43995, potential heap overflow for passwords < 8
characters. Starting with sudo 1.8.0 the plaintext password buffer is
dynamically sized so it is not safe to assume that it is at least 9 bytes in
size. Found by Hugo Lefeuvre (University of Manchester) with ConfFuzz.
---
plugins/sudoers/auth/passwd.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/plugins/sudoers/auth/passwd.c b/plugins/sudoers/auth/passwd.c
index b2046eca2..0416861e9 100644
--- a/plugins/sudoers/auth/passwd.c
+++ b/plugins/sudoers/auth/passwd.c
@@ -63,7 +63,7 @@ sudo_passwd_init(struct passwd *pw, sudo_auth *auth)
int
sudo_passwd_verify(struct passwd *pw, char *pass, sudo_auth *auth, struct sudo_conv_callback *callback)
{
- char sav, *epass;
+ char des_pass[9], *epass;
char *pw_epasswd = auth->data;
size_t pw_len;
int matched = 0;
@@ -75,12 +75,12 @@ sudo_passwd_verify(struct passwd *pw, char *pass, sudo_auth *auth, struct sudo_c
/*
* Truncate to 8 chars if standard DES since not all crypt()'s do this.
- * If this turns out not to be safe we will have to use OS #ifdef's (sigh).
*/
- sav = pass[8];
pw_len = strlen(pw_epasswd);
- if (pw_len == DESLEN || HAS_AGEINFO(pw_epasswd, pw_len))
- pass[8] = '\0';
+ if (pw_len == DESLEN || HAS_AGEINFO(pw_epasswd, pw_len)) {
+ strlcpy(des_pass, pass, sizeof(des_pass));
+ pass = des_pass;
+ }
/*
* Normal UN*X password check.
@@ -88,7 +88,6 @@ sudo_passwd_verify(struct passwd *pw, char *pass, sudo_auth *auth, struct sudo_c
* only compare the first DESLEN characters in that case.
*/
epass = (char *) crypt(pass, pw_epasswd);
- pass[8] = sav;
if (epass != NULL) {
if (HAS_AGEINFO(pw_epasswd, pw_len) && strlen(epass) == DESLEN)
matched = !strncmp(pw_epasswd, epass, DESLEN);

View File

@@ -4,6 +4,7 @@ SRC_URI = "https://www.sudo.ws/dist/sudo-${PV}.tar.gz \
${@bb.utils.contains('DISTRO_FEATURES', 'pam', '${PAM_SRC_URI}', '', d)} \
file://0001-sudo.conf.in-fix-conflict-with-multilib.patch \
file://0001-lib-util-mksigname.c-correctly-include-header-for-ou.patch \
file://CVE-2022-43995.patch \
"
PAM_SRC_URI = "file://sudo.pam"