Tie Patch lifetime to its input buffers #523
Merged
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It's currently possible to get a use-after-free errors when using
Patch::from_buffers
. Here's a small code to repro:On my system it fails in ~5% cases, so it may be hard to repro. That happens because we're passing
old_file.content()
/old_file.content()
pointers, free them withmem::drop
and try to use them again.We also don't attempt to double free the pointers in
patch_generated_free
duringPatch
drop, since we don't haveGIT_DIFF_FLAG__FREE_DATA
flags on theirsgit_diff_file_content
.I understand that this change could break a lot of code and probably is overly defensive, since I'm not sure if other
Patch::from_*
functions behave the same, so I'm open to suggestions on how to improve this PR!