Systemd unit crashing when running with MemoryDenyWriteExecute=true about btcli4j HOT 7 CLOSED

Mh this is a very strange issue, what version of java you do have? (java --version)

and also, what os you are using?

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Hi @vincenzopalazzo,

I'm using Debian with OpenJDK:

openjdk 11.0.13 2021-10-19
OpenJDK Runtime Environment (build 11.0.13+8-post-Debian-1deb10u1)
OpenJDK Server VM (build 11.0.13+8-post-Debian-1deb10u1, mixed mode, sharing)

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In summary, what is the goal that you want achieve with MemoryDenyWriteExecute?

@vincenzopalazzo it's a generic security measure for systemd units, so I'm just trying to achieve better security for my node I guess.

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ok I'm back @sha-265.

I opened a talk on Reddit and a person pointed me out the systemd doc that says the following

Note that this option is incompatible with programs and libraries that generate program code dynamically at runtime, including JIT execution engines, executable stacks, and code "trampoline" feature of various C compilers.

You can see more here https://www.reddit.com/r/javahelp/comments/rwto7p/comment/hrefk6f/?utm_source=share&utm_medium=web2x&context=3

doc reference https://www.freedesktop.org/software/systemd/man/systemd.exec.html

I think we can't do-nothings about that.

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HI @sha-265,

So this error is strange because I'm running the plugin for months on debian with the OpenJDK version, and I don't have this problem.

I read somethings about permission error on linux env https://community.oracle.com/tech/developers/discussion/2077930/cannot-restore-segment-prot-after-reloc-permission-denied and this give me some idea that the problem can be related to the user permission?

Or any idea how to reproduce this problem?

In addition, there is also an OpenJDK issue here https://bugs.openjdk.java.net/browse/JDK-6538311 where several fixes are suggested, but all at os level, do you find these resources helpful?

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@vincenzopalazzo, are you running c-lightning as systemd unit with MemoryDenyWriteExecute set to true? Because this problem occurs only under this condition. If I'm running c-lightning with the plugin and MemoryDenyWriteExecute set to false, it's working great.

I think all the issues you mentioned, related to selinux, which I have disabled on my system. As I mentioned the problem related to the systemd's MemoryDenyWriteExecute setting.

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HI @sha-265,

Sorry for the delay here. You have right, I'm not using systems and also I don't know how MemoryDenyWriteExecute works.

I need to make some research before telling what can be the problem, but it looks like that there is some os permission error. The only way to solve this I think is to see if we need to change the way that runs the JVM or compile the jar.

In summary, what is the goal that you want achieve with MemoryDenyWriteExecute?

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