#24 UnsatisfiedLinkError upon sevenzipbinding initialization

[Dani Gelmanovich]

Hi,

I am using sevenzipjbinding-AllPlatforms-4.65-1.06-rc.jar on Ubuntu 12.04 from java application.
It was stable for long time but suddenly i received the following error:

java.lang.UnsatisfiedLinkError: /data/manager/tmp/SevenZipJBinding-bqNzq/lib7-Zip-JBinding.so: /data/manager/tmp/SevenZipJBinding-bqNzq/lib7-Zip-JBinding.so: failed to map segment from shared object: Operation not permitted
        at java.lang.ClassLoader$NativeLibrary.load(Native Method) ~[na:1.8.0_91]
        at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1941) ~[na:1.8.0_91]
        at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1824) ~[na:1.8.0_91]
        at java.lang.Runtime.load0(Runtime.java:809) ~[na:1.8.0_91]
        at java.lang.System.load(System.java:1086) ~[na:1.8.0_91]
        at net.sf.sevenzipjbinding.SevenZip.loadNativeLibraries(SevenZip.java:509) ~[sevenzipjbinding-4.65-1.06-rc.jar:na]
        ... 49 common frames omitted
Wrapped by: net.sf.sevenzipjbinding.SevenZipNativeInitializationException: 7-Zip-JBinding initialization failed: Error loading native library: '/data/manager/tmp/SevenZipJBinding-bqNzq/lib7-Zip-JBinding.so'

After that 7zip just refused to be initialized no matter what i tried. The only solution that worked for me was to reinstall the application which redeployed the 7zip files.
I looked at the permissins of /data/manager/tmp and it have rwx permissions as it supposed to be.
I dont have any clue in our logs why this happened.

1. Can you maybe help us to understand what may cause such error to appear? This might help us to prepare and protect our app from such cases
2. How this can be fixed "Gracefully"? (no server reboot\app reinstalling)

Thanks a lot in advance,
Dani Gelmanovich

[Boris Brodski]

Hello Dani,

this is very strange bug. You need "x" permission on the files in the tmp directory. If you mount your tmp directory you may try

sudo mount /tmp -o remount,exec

If you are using 7-Zip-JBinding within your project, that you install on the system, you may change the installer to create your own tmp-directory and then initialize 7-Zip-JBinding passing this directory as a tmp directory to use:

• http://sevenzipjbind.sourceforge.net/javadoc/net/sf/sevenzipjbinding/SevenZip.html#initSevenZipFromPlatformJAR(java.io.File)
• http://sevenzipjbind.sourceforge.net/javadoc/net/sf/sevenzipjbinding/SevenZip.html

The installer may also check the new tmp directory for the required permissions and enough space beforehand.

I hope, it helps.

Cheers,
Boris

[Dani Gelmanovich]

Hi,

I think i got it:
/data/manager/tmp was my temp folder for sevenzip and it had indeed rwx permissions.
The issue is that the partition of /data is set with "noexec" flag. I thing that this might be the root cause.
Maybe its a good chance to add guidelines in the documentation indicating that the partition of the tmp folder must not have "noexec" flag