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pablogsal/gist:692bb946d69f308144f6cd64e4e45f33

Created August 21, 2024 11:39
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investigation.md
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gistfile1.txt
Attaching and calling dlopen fails:
```
(gdb) call (void*)dlopen(0, 2) │>>> test test_exceptions failed -- Traceback (most recent call last):
Couldn't write extended state status: Bad address. │ File "/opt/_internal/cpython-3.8.13/lib/python3.8/test/test_exceptions.py", line 1256, in test_memory_error_in_PyErr_PrintEx
An error occurred while in a function called from GDB. │ rc, out, err = script_helper.assert_python_failure("-c", code % i)
Evaluation of the expression containing the function │ File "/opt/_internal/cpython-3.8.13/lib/python3.8/test/support/script_helper.py", line 167, in assert_python_failure
(dlopen@plt) will be abandoned. │ return _assert_python(False, *args, **env_vars)
When the function is done executing, GDB will silently stop. │ File "/opt/_internal/cpython-3.8.13/lib/python3.8/test/support/script_helper.py", line 141, in _assert_python
(gdb)
```
Looks like there is some incompatibility with the kernel (check for instance https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=898048).
Looking at the last working run and the first failed one we can see:
Working:
```
Current runner version: '2.317.0'
Operating System
Ubuntu
22.04.4
LTS
Runner Image
Image: ubuntu-22.04
Version: 20240804.1.0
Included Software: https://github.com/actions/runner-images/blob/ubuntu22/20240804.1/images/ubuntu/Ubuntu2204-Readme.md
Image Release: https://github.com/actions/runner-images/releases/tag/ubuntu22%2F20240804.1
```
failing:
```
Current runner version: '2.319.0'
Operating System
Ubuntu
22.04.4
LTS
Runner Image
Image: ubuntu-22.04
Version: 20240811.1.0
Included Software: https://github.com/actions/runner-images/blob/ubuntu22/20240811.1/images/ubuntu/Ubuntu2204-Readme.md
Image Release: https://github.com/actions/runner-images/releases/tag/ubuntu22%2F20240811.1
Runner Image Provisioner
2.0.374.1
```
Looks like this includes a kernel change, although very small:
https://github.com/actions/runner-images/releases/tag/ubuntu24%2F20240811.1
@pablogsal
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Technically is any call:

call printf("hehe\n")
Couldn't write extended state status: Bad address.
An error occurred while in a function called from GDB.
Evaluation of the expression containing the function
(printf) will be abandoned.
When the function is done executing, GDB will silently stop.

@pablogsal
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Check also hugsy/gef#449 and microsoft/debugpy#1480

@pablogsal
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https://launchpad.net/ubuntu/+source/linux-azure/6.8.0-1010.10

vs

https://launchpad.net/ubuntu/+source/linux-azure/6.8.0-1012.14

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