Description

devdanzin

opened on Oct 26, 2024

Issue body actions

Crash report

What happened?

There is an assert in sysmodule.c that makes the interpreter abort when calling sys.audit with a non-string value in debug builds:

cpython/Python/sysmodule.c

Line 522 in f6cc7c8

assert(PyUnicode_Check(args[0]));

Python 3.14.0a1+ (heads/main:c5b99f5c2c, Oct 26 2024, 12:35:53) [GCC 13.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.audit(9)
python: ./Python/sysmodule.c:522: sys_audit: Assertion `PyUnicode_Check(args[0])' failed.
Aborted (core dumped)

This assert seems completely unnecessary, as the code that runs the hooks (which only triggers if there is some hook registered) will raise an exception if the first argument to sys.audit isn't a string:

Python 3.14.0a1+ (heads/remove_sysaudit_assert:ba8ac4d398, Oct 26 2024, 19:45:11) [GCC 11.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.addaudithook(lambda *args: None)
>>> sys.audit(9)
Traceback (most recent call last):
  File "<python-input-2>", line 1, in <module>
    sys.audit(9)
    ~~~~~~~~~^^^
TypeError: expected str for argument 'event', not int

I'll submit a trivial PR removing this assert.

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux, Windows

Output from running 'python -VV' on the command line:

Python 3.14.0a1+ (heads/main:c5b99f5c2c, Oct 26 2024, 12:35:53) [GCC 13.2.0]

Linked PRs

• gh-126018: Avoid aborting due to unnecessary assert in sys.audit #126020
• [3.13] gh-126018: Avoid aborting due to unnecessary assert in sys.audit (GH-126020) #126042

Activity

1. devdanzin

   added

   type-crashA hard crash of the interpreter, possibly with a core dumpA hard crash of the interpreter, possibly with a core dump

   on Oct 26, 2024
2. Eclips4

   added

   interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

   extension-modulesC modules in the Modules dirC modules in the Modules dir

   on Oct 26, 2024
3. picnixz

   added

   3.12only security fixesonly security fixes

   3.13only security fixesonly security fixes

   3.14bugs and security fixesbugs and security fixes

   on Oct 26, 2024
4. picnixz commented on Oct 26, 2024

   

   picnixz

   on Oct 26, 2024

   Member

   More actions

   Ok, 3.12 is actually not affected:

   cpython/Python/sysmodule.c

   Lines 499 to 514 in 67b2701

   	if (!should_audit(tstate->interp)) {
   	Py_RETURN_NONE;
   	}
   	PyObject *auditEvent = args[0];
   	if (!auditEvent) {
   	_PyErr_SetString(tstate, PyExc_TypeError,
   	"expected str for argument 'event'");
   	return NULL;
   	}
   	if (!PyUnicode_Check(auditEvent)) {
   	_PyErr_Format(tstate, PyExc_TypeError,
   	"expected str for argument 'event', not %.200s",
   	Py_TYPE(auditEvent)->tp_name);
   	return NULL;
   	}
5. picnixz

   removed

   3.12only security fixesonly security fixes

   on Oct 26, 2024
6. devdanzin commented on Oct 27, 2024

   

   devdanzin

   on Oct 27, 2024

   MemberAuthor

   More actions

   Ok, 3.12 is actually not affected:

   Hmm. The assert was deliberately added in #108965. @vstinner, what do you think about the proposal to remove the eager assert for non-string argument to sys.audit?
7. JelleZijlstra

   added a commit that references this issue on Oct 27, 2024

   gh-126018: Avoid aborting due to unnecessary assert in `sys.audit` (#…

   80eec52
8. miss-islington

   added a commit that references this issue on Oct 27, 2024

   pythongh-126018: Avoid aborting due to unnecessary assert in `sys.aud…

   e0eeb70
9. JelleZijlstra

   added a commit that references this issue on Oct 27, 2024

   [3.13] gh-126018: Avoid aborting due to unnecessary assert in `sys.au…

   e4157f0
10. picnixz commented on Oct 27, 2024

    

    picnixz

    on Oct 27, 2024

    Member

    More actions

    Closing since completed and backported. Thanks!
11. picnixz

    closed this as completedon Oct 27, 2024
12. picnixz

    added a commit that references this issue on Dec 8, 2024

    pythongh-126018: Avoid aborting due to unnecessary assert in `sys.aud…

    353994f
13. ebonnal

    added a commit that references this issue on Jan 12, 2025

    pythongh-126018: Avoid aborting due to unnecessary assert in `sys.aud…

    3a9bc3f

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