gh-101178: Fix possible integer overflow in Ascii85 encoder with wrapcol=1#144778
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serhiy-storchaka merged 1 commit intoFeb 24, 2026
python:mainpython/cpython:mainfrom
serhiy-storchaka:ascii85-encode-integer-overflowserhiy-storchaka/cpython:ascii85-encode-integer-overflowCopy head branch name to clipboard
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gh-101178: Fix possible integer overflow in Ascii85 encoder with wrapcol=1#144778serhiy-storchaka merged 1 commit intopython:mainpython/cpython:mainfrom serhiy-storchaka:ascii85-encode-integer-overflowserhiy-storchaka/cpython:ascii85-encode-integer-overflowCopy head branch name to clipboard
serhiy-storchaka merged 1 commit into
python:mainpython/cpython:mainfrom
serhiy-storchaka:ascii85-encode-integer-overflowserhiy-storchaka/cpython:ascii85-encode-integer-overflowCopy head branch name to clipboard
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…h wrapcol=1 It could happen if the size of the input is more than 4/5 of sys.maxsize (only feasible on 32-bit platforms). Also simplify the integer overflow checks in the Base64 encoder, and harmonize them with the code for Ascii85 and Base85.
sethmlarson
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Feb 13, 2026
| out_len -= 4 - (bin_len % 4); | ||
| } | ||
| if (wrapcol && out_len) { | ||
| if (wrapcol && out_len && out_len <= PY_SSIZE_T_MAX) { |
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Let me know if I'm misunderstanding, but wouldn't we need to "error out" if the out_len would overflow here instead of not expanding? The larger amount of data will still be written outside ascii_data whether out_len is expanded or not?
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We error out in the next "if".
brijkapadia
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Feb 28, 2026
…h wrapcol=1 (pythonGH-144778) It could happen if the size of the input is more than 4/5 of sys.maxsize (only feasible on 32-bit platforms). Also simplify the integer overflow checks in the Base64 encoder, and harmonize them with the code for Ascii85 and Base85.
ljfp
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Apr 25, 2026
…h wrapcol=1 (pythonGH-144778) It could happen if the size of the input is more than 4/5 of sys.maxsize (only feasible on 32-bit platforms). Also simplify the integer overflow checks in the Base64 encoder, and harmonize them with the code for Ascii85 and Base85.
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It could happen if the size of the input is more than 4/5 of sys.maxsize (only feasible on 32-bit platforms).
Also simplify the integer overflow checks in the Base64 encoder, and harmonize them with the code for Ascii85 and Base85.