LD_LIBRARY_PATH not taken into account

[Wernfried]

I am referring to this topic: #2424

In order to use latest SQLite features I replaced file /usr/lib64/libsqlite3.so.0.8.6 with latest compiled version of sqlite source code. In general everything is working fine.

Problem is shared object /usr/lib64/libsqlite3.so.0.8.6 might be replaced again by outdated version if the admin applies any standard Linux patches. So I decided to move the latest shared object to private location /opt/mediation/lib and change LD_LIBRARY_PATH accordingly. However, syslog-ng does not use the new version, it seems to be hard-linked to /usr/lib64/libsqlite3.so.0.8.6

[mediation@t-mipmed-as-01 ~]$ echo $LD_LIBRARY_PATH
/opt/mediation/lib:/opt/app/oracle/product/11.2.0/client_1/lib

[mediation@t-mipmed-as-01 ~]$ ls -l /opt/mediation/lib/libsqlite3*
lrwxrwxrwx. 1 mediation mediation     19 Dec 10 08:20 /opt/mediation/lib/libsqlite3.so -> libsqlite3.so.0.8.6
lrwxrwxrwx. 1 mediation mediation     19 Dec 10 08:20 /opt/mediation/lib/libsqlite3.so.0 -> libsqlite3.so.0.8.6
-rwxr-xr-x. 1 mediation mediation 959345 Dec 10 07:59 /opt/mediation/lib/libsqlite3.so.0.8.6

[mediation@t-mipmed-as-01 ~]$ lsof -p 27965 | grep libsqlite3*
syslog-ng 27965 mediation  mem       REG              253,0   753232   83909662 /usr/lib64/libsqlite3.so.0.8.6

I run also a Perl script which uses SQLite, This perl script uses correct version /opt/mediation/lib/libsqlite3.so.0.8.6, so LD_LIBRARY_PATH is set properly.

I can force the correct file with LD_PRELOAD=/opt/mediation/lib/libsqlite3.so, however I wonder if this behavior is intended by syslog-ng or whether it should work with LD_LIBRARY_PATH only.

My impression is that LD_PRELOAD is more used for debugging and developing but less suitable for production code (but I might be wrong)

Best Regards

[bazsi]

Hmm, syslog-ng might be compiled in a mode where it does change LD_LIBRARY_PATH, the PE version uses that, but unless you are using that, you shouldn't be affected. If that's not the case, LD_LIBRARY_PATH should be taken into account. To troubleshoot you could always check /proc/<pid>/env like this: ``` $ cat /proc/<pid>/env | xargs -0 echo ``` And check if the environment variable is there.

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On Mon, Dec 10, 2018, 10:14 Wernfried ***@***.*** wrote: I am referring to this topic: #2424 <#2424> In order to use latest SQLite features I replaced file /usr/lib64/libsqlite3.so.0.8.6 with latest compiled version of sqlite source code. In general everything is working fine. Problem is shared object /usr/lib64/libsqlite3.so.0.8.6 might be replaced again by outdated version if the admin applies any standard Linux patches. So I decided to move the latest shared object to private location /opt/mediation/lib and change LD_LIBRARY_PATH accordingly. However, syslog-ng does not use the new version, it seems to be hard-linked to /usr/lib64/libsqlite3.so.0.8.6 ***@***.*** ~]$ echo $LD_LIBRARY_PATH /opt/mediation/lib:/opt/app/oracle/product/11.2.0/client_1/lib ***@***.*** ~]$ ls -l /opt/mediation/lib/libsqlite3* lrwxrwxrwx. 1 mediation mediation 19 Dec 10 08:20 /opt/mediation/lib/libsqlite3.so -> libsqlite3.so.0.8.6 lrwxrwxrwx. 1 mediation mediation 19 Dec 10 08:20 /opt/mediation/lib/libsqlite3.so.0 -> libsqlite3.so.0.8.6 -rwxr-xr-x. 1 mediation mediation 959345 Dec 10 07:59 /opt/mediation/lib/libsqlite3.so.0.8.6 ***@***.*** ~]$ lsof -p 27965 | grep libsqlite3* syslog-ng 27965 mediation mem REG 253,0 753232 83909662 /usr/lib64/libsqlite3.so.0.8.6 I run also a Perl script which uses SQLite, This perl script uses correct version /opt/mediation/lib/libsqlite3.so.0.8.6, so LD_LIBRARY_PATH is set properly. I can force the correct file with LD_PRELOAD=/opt/mediation/lib/libsqlite3.so.0.8.6, however I wonder if this behavior is intended by syslog-ng or whether it should work with LD_LIBRARY_PATH only. My impression is that LD_PRELOAD is more used for debugging and developing but less suitable for production code (but I might be wrong) Best Regards — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#2456>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AArldj9ys7yyCtJ4LQXJ81vpuOOhiVY1ks5u3iXTgaJpZM4ZK8OP> .

[Wernfried]

Yes, cat /proc/<pid>/env | xargs -0 echo show environment as expected:

LD_LIBRARY_PATH=/opt/mediation/lib:/opt/app/oracle/product/11.2.0/client_1/lib

[MrAnno]

LD_LIBRARY_PATH should work in general, but syslog-ng does not depend on libsqlite3 directly, it uses libdbi instead.
libdbi-dbd-sqlite is responsible for loading libsqlite3.

I would check whether /usr/lib64/dbd/libdbdsqlite3.so is force-linked to /usr/lib64/libsqlite3.so.0.8.6, for example:

LD_LIBRARY_PATH=/... ldd /usr/lib64/dbd/libdbdsqlite3.so

Please reopen this issue if you think it's an issue with syslog-ng, or you have further questions.