[Pkg-samba-maint] Bug#1116050: dlz_bind9_18.so let ISC bind die by NULL pointer dereference

[Benedikt Spranger]

Package: samba-libs
Version: 2:4.23.0+dfsg-3
Severity: important
Tags: patch upstream
X-Debbugs-Cc: b.spranger at linutronix.de

Dear package maintainer,
one patch says it all...

>From cb17ea65fd37b86aa84c423496aabfb8d22fc6b8 Mon Sep 17 00:00:00 2001
From: Benedikt Spranger <b.spranger at linutronix.de>
Date: Tue, 23 Sep 2025 15:38:29 +0200
Subject: [PATCH] Fix Bugfix 15288 - DLZ plugin is uninformative when binddns
 directory is inaccessible

Commit 3c53430eed4f ("s4/dns/dlz: log when falling back to obsolete dns
ldb path") tries to fix bug 1528. Unfortunally this fix end up in a NULL
pointer dereference, when try to inform the user about the issue.

During the first load dlz_bind9_state is NULL, and set to state at the
end of dlz_create(). Dereferencing dlz_bind9_state before setting it,
results in a NULL pointer dereference.

Make the Bugfix functional.

Signed-off-by: Benedikt Spranger <b.spranger at linutronix.de>
---
 source4/dns_server/dlz_bind9.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/source4/dns_server/dlz_bind9.c b/source4/dns_server/dlz_bind9.c
index e5c9679835e..d5e90286a7e 100644
--- a/source4/dns_server/dlz_bind9.c
+++ b/source4/dns_server/dlz_bind9.c
@@ -727,11 +727,11 @@ _PUBLIC_ isc_result_t dlz_create(const char *dlzname,
                }

                if (!file_exist(state->options.url)) {
-                       dlz_bind9_state->log(ISC_LOG_ERROR,
-                                            "samba_dlz: dlz_create could not find '%s'; "
-                                            "trying old location '%s/dns/sam.ldb' instead",
-                                            state->options.url,
-                                            lpcfg_private_dir(state->lp));
+                       state->log(ISC_LOG_ERROR,
+                                  "samba_dlz: dlz_create could not find '%s'; "
+                                  "trying old location '%s/dns/sam.ldb' instead",
+                                  state->options.url,
+                                  lpcfg_private_dir(state->lp));
                        state->options.url = talloc_asprintf(state,
                                                             "%s/dns/sam.ldb",
                                                             lpcfg_private_dir(state->lp));
--
2.51.0


-- System Information:
Debian Release: forky/sid
  APT prefers unstable-debug
  APT policy: (500, 'unstable-debug'), (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 6.16.8+deb14-amd64 (SMP w/4 CPU threads; PREEMPT)
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: sysvinit (via /sbin/init)
LSM: AppArmor: enabled

Versions of packages samba-libs depends on:
ii  libacl1                   2.3.2-2+b1
ii  libavahi-client3          0.8-17
ii  libavahi-common3          0.8-17
ii  libbsd0                   0.12.2-2
ii  libc6                     2.41-12
ii  libcap2                   1:2.75-10+b1
ii  libcrypt1                 1:4.4.38-1
ii  libgnutls30t64            3.8.10-2
ii  libicu76                  76.1-4
ii  libjansson4               2.14-2+b3
ii  libldap2                  2.6.10+dfsg-1
ii  libldb2                   2:2.11.0+samba4.23.0+dfsg-3
ii  libngtcp2-16              1.15.1-1
ii  libngtcp2-crypto-gnutls8  1.15.1-1
ii  libpam0g                  1.7.0-5
ii  libpopt0                  1.19+dfsg-2
ii  libsystemd0               258-1
ii  libtalloc2                2:2.4.3+samba4.23.0+dfsg-3
ii  libtdb1                   2:1.4.14+samba4.23.0+dfsg-3
ii  libtevent0t64             2:0.17.1+samba4.23.0+dfsg-3
ii  libtirpc3t64              1.3.6+ds-1
ii  libwbclient0              2:4.23.0+dfsg-3
ii  zlib1g                    1:1.3.dfsg+really1.3.1-1+b1

samba-libs recommends no packages.

samba-libs suggests no packages.

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