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Title: gh-90949: add Expat API to prevent XML deadly allocations by picnixz · Pull Request #139234 · python/cpython · GitHub

Open Graph Title: gh-90949: add Expat API to prevent XML deadly allocations by picnixz · Pull Request #139234 · python/cpython

X Title: gh-90949: add Expat API to prevent XML deadly allocations by picnixz · Pull Request #139234 · python/cpython

Description: @hartwork I observed that the maximum allocation factor is only checked if we exceed the activation threshold. The online docs for Expat didn't explicitly mention it so I mentioned it in our docs. I eventually decided to redo the float-check in case of an error so that we can give a better message to the user (as it relates to security practices, I think it's good to explain why the API call failed as much as we can). Issue: gh-90949 📚 Documentation preview 📚: https://cpython-previews--139234.org.readthedocs.build/

Open Graph Description: @hartwork I observed that the maximum allocation factor is only checked if we exceed the activation threshold. The online docs for Expat didn't explicitly mention it so I mentioned it in our do...

X Description: @hartwork I observed that the maximum allocation factor is only checked if we exceed the activation threshold. The online docs for Expat didn't explicitly mention it so I mentioned it in ou...

Opengraph URL: https://github.com/python/cpython/pull/139234

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c1c23fb Expose XML Expat 2.7.2 mitigation APIs picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/c1c23fbf29411a1c52b326874a95df1b8da65d64
12bef9c add tests picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/12bef9ceac44b3b70ef41bf97f389d0d8291721e
1d7e599 docs picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/1d7e599f4006603817c3242ecf786ae5a0b7b6df
3dcd9bd NEWS picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/3dcd9bd3228dad609ae6395d2175d0f83fe1facd
192fe08 Merge branch 'main' into feat/xml/mitigation-api-90949 picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/192fe082ad78a53014fd8c81b41d2517c7835a52
0ecbd55 fix docs picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/0ecbd5526c42cfa87d0f130df39ec531e59a2d6f
07445ad fix tests picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/07445ad2726123991e64eb63951ae35400601ea6
9c7371f regen SBOM picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/9c7371f416eaf70f7eaa2c73d8792c1dca8d5cc4
1085584 remove unused include picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/10855847249df4dd140e0a24b441dc6c3bca3846
c10fe91 fix possible error handling picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/c10fe919a75b94e43be526b8e3fa74ea9ea6f508
18d175f undef macro after usage picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/18d175f79098b864075d6a2f06f6cc8b3d61b2f3
911b2b7 Update Lib/test/test_pyexpat.py picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/911b2b7eb9e197ef28725a8292e82bb737c8fa4c
d636685 update comments picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/d63668539630127da9be8bad570590f9a1b4aab3
b951065 use better test names picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/b9510650de13c2b688e198f2df5fc0c7e0b9fca2
e11bf14 simplify roles usage picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/e11bf14f1f6d84ee16812f0c022699b7f7eab2b5
3e45613 prevent reparse deferral of Expat to blow up picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/3e45613aa75b803574040faaf60e78bbdb7eb3ab
fb83fb5 test better numeric values picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/fb83fb57c5bec75f7acc49c03463fdfdb17c7b1a
7f91f2e update docs picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/7f91f2e1ba2c37ac31cce7aee89dd7fb093b210a
64af05c avoid deprecated `XML_GetError{Line,Column}Number` picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/64af05ca6e16ce5b9ad408cb60fc134c27112524
b01e53d raise `NotImplementedError` for unavailable mitigation APIs picnixz Sep 22, 2025 https://github.com/python/cpython/pull/139234/commits/b01e53d80f545e14851b58d05c43de252995a879
cd040bf improve various wordings picnixz Sep 23, 2025 https://github.com/python/cpython/pull/139234/commits/cd040bff116ba31d230b29d1c52972656cf462da
a09cd15 avoid SBOM alteration picnixz Sep 23, 2025 https://github.com/python/cpython/pull/139234/commits/a09cd1545be11a0b61de404ee458bca28da97737
a3fc3b3 regen files picnixz Sep 23, 2025 https://github.com/python/cpython/pull/139234/commits/a3fc3b3724676fc2e645c4fd065d413078155f02
5afe1ad improve test assertions picnixz Sep 23, 2025 https://github.com/python/cpython/pull/139234/commits/5afe1adbf7436fff58dd06522573cb98b0fdb3bb
b6949dd improve test genericity picnixz Sep 23, 2025 https://github.com/python/cpython/pull/139234/commits/b6949dd992ea9943735cab6ccce4c7c0b588a839
bdbd382 split tests even if they could end up duplicated picnixz Sep 23, 2025 https://github.com/python/cpython/pull/139234/commits/bdbd3827c1f51d52f17ef1d0b2c946929dce0cbc
0c03735 raise AttributeError when method is not available and reorder interface picnixz Sep 23, 2025 https://github.com/python/cpython/pull/139234/commits/0c03735a64220e67a84c8335050324f334557c78
220f3e2 reoder docs picnixz Sep 23, 2025 https://github.com/python/cpython/pull/139234/commits/220f3e2885e87b77230a875045029be37465725f
9d538e4 address review picnixz Sep 24, 2025 https://github.com/python/cpython/pull/139234/commits/9d538e416d962d6649c69c5797b5fb343e2c8237
209f300 update capsule API picnixz Sep 24, 2025 https://github.com/python/cpython/pull/139234/commits/209f30027dbd7da72c325d37f243b0756f4baf24
8407cfc amend docs picnixz Sep 24, 2025 https://github.com/python/cpython/pull/139234/commits/8407cfcd298553f68e6dd29e1e74ff37d03ecea5
e898811 use "NOTE:" picnixz Sep 24, 2025 https://github.com/python/cpython/pull/139234/commits/e89881162987adfe49098334f9446af62e4d9804
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