Following the conversation in [1], here are patches to fix the murmur3 hash function used in creating (and interpreting) changed path filters, and also to bump the version number to 2. This is I think the simplest way to do this (invalidating all existing changed path filters). The resource-consuming part of creating a changed path filter is in computing the changed paths (thus, reading trees and calculating changes), and to check if a changed path filter could be reused, one would need to compute the changed paths anyway in order to determine if any of them have high-bit strings, so I did not pursue this further. Server operators might be able to reuse changed path filters if, for example, they have a more efficient way to determine that no paths in a repo have the high bit set, but I think that this is out of scope for the Git project. In patch 2, I couldn't figure out how to make Bash pass high-bit strings as a CLI argument for some reason, so I hardcoded the string I wanted in the test helper instead. If anyone knows how to pass such strings, please let me know. [1] https://lore.kernel.org/git/20230511224101.972442-1-jonathantanmy@xxxxxxxxxx/ Jonathan Tan (2): t4216: test wrong bloom filter version rejection commit-graph: fix murmur3, bump filter ver. to 2 bloom.c | 14 +++++++------- bloom.h | 9 ++++++--- commit-graph.c | 4 ++-- t/helper/test-bloom.c | 7 +++++++ t/t0095-bloom.sh | 8 ++++++++ t/t4216-log-bloom.sh | 36 +++++++++++++++++++++++++++++++++--- 6 files changed, 63 insertions(+), 15 deletions(-) -- 2.40.1.698.g37aff9b760-goog
