Compatibility issue debugging (8.5 + smbclient + oci8)

[duchymor]

Hello,
please, let me ask for a hint to debug a compatibility issue. So far I was able to create minimal failing example, but I'm not sure on which element I should focus or how.
The issue is - after update, there's a Segmentation fault (core dumped) during smbclient_open. It only happens on PHP 8.5 (trixie/bookworm/alpine) with oci8 installed as well.

FROM php:8.5-fpm-trixie

ADD https://github.com/mlocati/docker-php-extension-installer/releases/latest/download/install-php-extensions /usr/local/bin/
RUN chmod +x /usr/local/bin/install-php-extensions && \
    install-php-extensions \
    oci8 \
    smbclient

RUN php <<'PHP'
<?php
$state = smbclient_state_new();
smbclient_state_init($state, "***", "***", "***");
smbclient_open($state, "smb://***", "r");
PHP

[mlocati]

I can't replicate your issue...

Here's a sample session in a php:8.5-fpm-trixie docker container:

root@778eb3c64bb2:/# cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 13 (trixie)"
NAME="Debian GNU/Linux"
VERSION_ID="13"
VERSION="13 (trixie)"
VERSION_CODENAME=trixie
DEBIAN_VERSION_FULL=13.3
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"


root@778eb3c64bb2:/# php -v
PHP 8.5.3 (cli) (built: Feb 24 2026 19:07:12) (NTS)
Copyright (c) The PHP Group
Built by https://github.com/docker-library/php
Zend Engine v4.5.3, Copyright (c) Zend Technologies
    with Zend OPcache v8.5.3, Copyright (c), by Zend Technologies


root@778eb3c64bb2:/# install-php-extensions oci8 smbclient >/dev/null


root@778eb3c64bb2:/# php --ri oci8

oci8

OCI8 Support => enabled
OCI8 DTrace Support => disabled
OCI8 Version => 3.4.1
Oracle Run-time Client Library Version => 21.1.0.0.0
Oracle Compile-time Instant Client Version => 21.1

Directive => Local Value => Master Value
oci8.max_persistent => -1 => -1
oci8.persistent_timeout => -1 => -1
oci8.ping_interval => 60 => 60
oci8.privileged_connect => Off => Off
oci8.statement_cache_size => 20 => 20
oci8.default_prefetch => 100 => 100
oci8.old_oci_close_semantics => Off => Off
oci8.connection_class => no value => no value
oci8.events => Off => Off
oci8.prefetch_lob_size => 0 => 0

Statistics =>
Active Persistent Connections => 0
Active Connections => 0


root@778eb3c64bb2:/# php --ri smbclient

smbclient

smbclient Support => enabled
smbclient extension Version => 1.2.0dev
libsmbclient library Version => 4.22.6-Debian-4.22.6+dfsg-0+deb13u1


root@778eb3c64bb2:/# php <<'PHP'
<?php
$state = smbclient_state_new();
smbclient_state_init($state, "***", "***", "***");
smbclient_open($state, "smb://***", "r");
PHP

Warning: Couldn't open smb://***: No file? in Standard input code on line 4

[duchymor]

Sorry, I forgot to mention to replace asterisks with something real. This is unfortunately not portable, but for me it fails the same way if I use local windows shared directory:

<?php
$state = smbclient_state_new();
smbclient_state_init($state, "WORKGROUP", "admin", "1234");
smbclient_open($state, "smb://10.53.201.60/dummydir/dummyfile.txt", "r");

[duchymor]

I got lucky trying this workaround in Dockerfile:
RUN mv /usr/local/etc/php/conf.d/docker-php-ext-smbclient.ini /usr/local/etc/php/conf.d/docker-php-ext-1-smbclient.ini
It makes smbclient to load before oci8 and the issue is gone.
Unfortunately changing the order during install cannot affect this. I'm not sure if it could be helpful to have such a feature, but this seems to be an edge case.

[mlocati]

I've been able to reproduce the segmentation fault...

$ IPE_NOSTRIP=1 install-php-extensions oci8 smbclient

$ apt-get update -q

$ apt-get install -qy --no-install-recommends samba gdb

$ mkdir -p /tmp/test-samba

$ cat <<'EOT' >>/etc/samba/smb.conf
[test_samba]
    path = /tmp/test-samba
    read only = yes
    browsable = yes
EOT

$ service smbd restart

$ gdb php

(gdb) run -r '$state = smbclient_state_new(); smbclient_state_init($state); smbclient_open($state, "smb://127.0.0.1/test_samba/test.txt", "r");'
Starting program: /usr/local/bin/php -r '$state = smbclient_state_new(); smbclient_state_init($state); smbclient_open($state, "smb://127.0.0.1/test_samba/test.txt", "r");'
warning: Error disabling address space randomization: Operation not permitted
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Program received signal SIGSEGV, Segmentation fault.
0x000073657c2e5262 in free () from /lib/x86_64-linux-gnu/libc.so.6

(gdb) bt
#0  0x000073657c2e5262 in free () from /lib/x86_64-linux-gnu/libc.so.6
#1  0x0000736578b666dd in krb5_free_context () from /usr/lib/oracle/21.1/client64/lib/libclntsh.so.21.1
#2  0x0000736574cd1069 in smb_krb5_init_context_basic () from /usr/lib/x86_64-linux-gnu/samba/libauthkrb5-private-samba.so.0
#3  0x0000736574cd12e0 in smb_krb5_init_context () from /usr/lib/x86_64-linux-gnu/samba/libauthkrb5-private-samba.so.0
#4  0x0000736575d221ef in cli_credentials_get_krb5_context () from /lib/x86_64-linux-gnu/libsamba-credentials.so.1
#5  0x0000736575d2257a in cli_credentials_set_ccache () from /lib/x86_64-linux-gnu/libsamba-credentials.so.1
#6  0x0000736575d20b2d in cli_credentials_guess () from /lib/x86_64-linux-gnu/libsamba-credentials.so.1
#7  0x0000736575f7ab3b in auth_generic_client_prepare () from /usr/lib/x86_64-linux-gnu/samba/liblibsmb-private-samba.so.0
#8  0x0000736575f805f0 in cli_session_setup_creds_send () from /usr/lib/x86_64-linux-gnu/samba/liblibsmb-private-samba.so.0
#9  0x0000736575f80f4d in cli_session_setup_creds () from /usr/lib/x86_64-linux-gnu/samba/liblibsmb-private-samba.so.0
#10 0x000073657b3bad85 in ?? () from /lib/x86_64-linux-gnu/libsmbclient.so.0
#11 0x000073657b3bb642 in ?? () from /lib/x86_64-linux-gnu/libsmbclient.so.0
#12 0x000073657b3b8732 in ?? () from /lib/x86_64-linux-gnu/libsmbclient.so.0
#13 0x000073657b60df1f in zif_smbclient_open (execute_data=<optimized out>, return_value=0x7ffcd2241dd0) at /tmp/pear/temp/smbclient/smbclient.c:1119
#14 0x000056d5599b01c3 in execute_ex ()
#15 0x000056d5599aa0d3 in zend_execute ()
#16 0x000056d5599591b1 in zend_eval_stringl ()
#17 0x000056d559959389 in zend_eval_stringl_ex ()
#18 0x000056d559a15174 in ?? ()
#19 0x000056d55945cc5b in ?? ()
#20 0x000073657c26bca8 in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#21 0x000073657c26bd65 in __libc_start_main () from /lib/x86_64-linux-gnu/libc.so.6
#22 0x000056d55945e061 in _start ()

#1251 should fix this problem