Mono C# In chroot

**Paris.K** · August 4th, 2012

Hello,

I 'd like to run some C# programs in a chroot. I copied the following inside my jail

My program (program.exe)
/bin/sh and libraries found by ldd
/bin/bash and libraries found by ldd
/usr/bin/mono
/usr/lib/mono

When I try to run my program like this:

Code:

sudo chroot jail ./program.exe

, I get the error message that this program does not exist. Mono C# does not do Dynamic Linking, so I cannot find the libraries on which my program depends, by using ldd. Could you please help me with that?

Thanks

**Sslaxx** · August 4th, 2012

A mono-created program relies upon the .NET framework being present. Also, by default Ubuntu won't know what to do with the program.exe file - you'd need to run it as "mono ./program.exe" - which, if you're running it from a chroot jail, might be tricky.

**directhex** · August 6th, 2012

Originally Posted by Paris.K

Hello,

I 'd like to run some C# programs in a chroot. I copied the following inside my jail

My program (program.exe)
/bin/sh and libraries found by ldd
/bin/bash and libraries found by ldd
/usr/bin/mono
/usr/lib/mono

When I try to run my program like this:

Code:

sudo chroot jail ./program.exe

, I get the error message that this program does not exist. Mono C# does not do Dynamic Linking, so I cannot find the libraries on which my program depends, by using ldd. Could you please help me with that?

Thanks

running Mono executables directly, as "./program.exe" (rather than as "mono program.exe") requires that /proc be mounted, and that the binfmt_misc kernel module be loaded, and that binfmt_misc be mounted to /proc/sys/fs/binfmt_misc, and that ':CLR:M::MZ::/usr/bin/mono:' be echoed into /proc/sys/fs/binfmt_misc/register

It's automated by the binfmt-support package

And I'd certainly not consider doing it inside a chroot. The Mono app deployment guidelines strongly caution against using "./foo.exe" rather than "mono foo.exe" precisely because it causes this kind of problem.