gh-145105: Fix crash in csv.reader with re-entrant iterator#145106
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gpshead merged 1 commit intopython:mainfrom Apr 11, 2026
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gh-145105: Fix crash in csv.reader with re-entrant iterator#145106gpshead merged 1 commit intopython:mainfrom
gpshead merged 1 commit intopython:mainfrom
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When a custom iterator calls next() on the same csv.reader from within __next__, the inner iteration sets self->fields to NULL. The outer iteration then crashes in parse_save_field() by passing NULL to PyList_Append. Add a guard after PyIter_Next() to detect that fields was set to NULL by a re-entrant call, and raise csv.Error instead of crashing.
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esoteric seeming but true. thanks!
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…thonGH-145106) When a custom iterator calls next() on the same csv.reader from within __next__, the inner iteration sets self->fields to NULL. The outer iteration then crashes in parse_save_field() by passing NULL to PyList_Append. Add a guard after PyIter_Next() to detect that fields was set to NULL by a re-entrant call, and raise csv.Error instead of crashing. (cherry picked from commit 20994b1809f9c162e4cae01a5af08bd492ede9f9) Co-authored-by: Ramin Farajpour Cami <ramin.blackhat@gmail.com>
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GH-148404 is a backport of this pull request to the 3.14 branch. |
miss-islington
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Apr 11, 2026
…thonGH-145106) When a custom iterator calls next() on the same csv.reader from within __next__, the inner iteration sets self->fields to NULL. The outer iteration then crashes in parse_save_field() by passing NULL to PyList_Append. Add a guard after PyIter_Next() to detect that fields was set to NULL by a re-entrant call, and raise csv.Error instead of crashing. (cherry picked from commit 20994b1) Co-authored-by: Ramin Farajpour Cami <ramin.blackhat@gmail.com>
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GH-148405 is a backport of this pull request to the 3.13 branch. |
gpshead
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…H-145106) (#148405) gh-145105: Fix crash in csv.reader with re-entrant iterator (GH-145106) When a custom iterator calls next() on the same csv.reader from within __next__, the inner iteration sets self->fields to NULL. The outer iteration then crashes in parse_save_field() by passing NULL to PyList_Append. Add a guard after PyIter_Next() to detect that fields was set to NULL by a re-entrant call, and raise csv.Error instead of crashing. (cherry picked from commit 20994b1) Co-authored-by: Ramin Farajpour Cami <ramin.blackhat@gmail.com>
gpshead
pushed a commit
that referenced
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Apr 11, 2026
…H-145106) (#148404) gh-145105: Fix crash in csv.reader with re-entrant iterator (GH-145106) When a custom iterator calls next() on the same csv.reader from within __next__, the inner iteration sets self->fields to NULL. The outer iteration then crashes in parse_save_field() by passing NULL to PyList_Append. Add a guard after PyIter_Next() to detect that fields was set to NULL by a re-entrant call, and raise csv.Error instead of crashing. (cherry picked from commit 20994b1) Co-authored-by: Ramin Farajpour Cami <ramin.blackhat@gmail.com>
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The fix adds a guard right after
PyIter_Nextreturns: ifself->fieldshas been set toNULLby a re-entrant call, raisecsv.Errorinstead of continuing intoparse_process_char._csv.reader: NULL deref via re-entrant iterator #145105