[receive] fix sequence number check bug #43
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
stewartadam
previously approved these changes
Dec 28, 2025
Contributor
stewartadam
left a comment
stewartadam
left a comment
There was a problem hiding this comment.
Look good, thank you for adding the test to validate the fix as well!
src/receive.rs
Outdated
Comment on lines
3313
to
3315
| // | ||
| // Current implementation likely FAILS because it computes diff using normal | ||
| // integer subtraction rather than signed 8-bit arithmetic. |
Contributor
There was a problem hiding this comment.
Suggested change
| // | |
| // Current implementation likely FAILS because it computes diff using normal | |
| // integer subtraction rather than signed 8-bit arithmetic. | |
| // | |
| // Current implementation likely FAILS because it computes diff using normal | |
| // integer subtraction rather than signed 8-bit arithmetic. |
To avoid the docstring falling out of date, I suggest removing this. The test pass/fail will track correct behavior and if our implementation follows it.
stewartadam
approved these changes
Dec 29, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Fix logic bug that wrongly accepts packets when wrapping the u8 sequence number range.
old seq number: 1
new seq number 254
e1.31 spec says to discard since it is within the -20, 0 difference range.
current seq diff on main: 254 - 1 = 253 as isize
accepted incorrectly
this pr: 254 - 1 = 253 as i8 = -3
-3 is within the discard window, so it correctly discards the packet.