gh-99240: Reset pointer to NULL when the pointed memory is freed in argument parsing by colorfulappl · Pull Request #99890 · python/cpython

colorfulappl

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In the family of _PyArg_Parse functions, pointers can be passed in as arguments to store the parsed PyArgs.
If a pointer is assigned to newly allocated memory and the memory is freed as a result of an error while parsing the subsequent PyArgs, the pointer should be set to NULL; otherwise, it leaks the freed memory.

Issue: Double-free in Argument Clinic str_converter generated code #99240

This fix corresponds to my comment in #99240

If function _PyArg_ParseStack parses failed, assign all the parsed arguments to "NULL" after they are freed, this should be done in _PyArg_ParseStack.

Can you add a test for this?

carljm changed the title ~~gh-99240: Reset pointer to NULL then the pointed memory is freed in argument parsing~~ gh-99240: Reset pointer to NULL when the pointed memory is freed in argument parsing

Dec 15, 2022

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LGTM

Sorry, @colorfulappl and @kumaraditya303, I could not cleanly backport this to 3.11 due to a conflict.
Please backport using cherry_picker on command line.
cherry_picker a6f82f1fc68cb24e2d88d35fde4cfb663213a744 3.11

Sorry, @colorfulappl and @kumaraditya303, I could not cleanly backport this to 3.10 due to a conflict.
Please backport using cherry_picker on command line.
cherry_picker a6f82f1fc68cb24e2d88d35fde4cfb663213a744 3.10

kumaraditya303 added a commit to kumaraditya303/cpython that referenced this pull request

Dec 17, 2022

…d in argument parsing (python#99890)

Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>

shihai1991 added a commit to shihai1991/cpython that referenced this pull request

Dec 18, 2022

@colorfulappl Can you create the backport PRs?

Sure. I will do this later.

carljm added a commit to carljm/cpython that referenced this pull request

Dec 19, 2022

colorfulappl added a commit to colorfulappl/cpython that referenced this pull request

Dec 21, 2022

…is freed in argument parsing (pythonGH-99890)

(cherry picked from commit efbb1eb)

Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>

colorfulappl added a commit to colorfulappl/cpython that referenced this pull request

Dec 21, 2022

…is freed in argument parsing (pythonGH-99890)

(cherry picked from commit efbb1eb)

Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>

kumaraditya303 added a commit that referenced this pull request

Dec 21, 2022

…ed in argument parsing (GH-99890) (#100385)

(cherry picked from commit efbb1eb)

Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>

kumaraditya303 added a commit that referenced this pull request

Dec 21, 2022

…ed in argument parsing (GH-99890) (#100386)

(cherry picked from commit efbb1eb)

Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>

rwgk pushed a commit to rwgk/cpython that referenced this pull request

Mar 11, 2023

…d in argument parsing (python#99890)

Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>