erts: Set recvmmsg data length to the receive buffer size - #11335
Merged
Conversation
In essio_recvmmsg, msg_len is used both to copy the received data out of the shared receive buffer and to size the result binary. With MSG_TRUNC the kernel reports the untruncated datagram length in msg_len even though only buffer-size bytes were actually stored, so using it unset copies past the buffer (heap-buffer-overflow) and sizes a binary larger than its allocation.
Contributor
CT Test Results 4 files 199 suites 1h 54m 41s ⏱️ For more details on these failures, see this check. Results for commit 5536c58. ♻️ This comment has been updated with latest results. To speed up review, make sure that you have read Contributing to Erlang/OTP and that all checks pass. See the TESTING and DEVELOPMENT HowTo guides for details about how to run test locally. Artifacts// Erlang/OTP Github Action Bot |
RaimoNiskanen
self-requested a review
July 3, 2026 14:25
RaimoNiskanen
added
team:PS
RaimoNiskanen
added
the
testing
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
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
In essio_recvmmsg, msg_len is used both to copy the received data out of the shared receive buffer and to size the result binary. With MSG_TRUNC the kernel reports the untruncated datagram length in msg_len even though only buffer-size bytes were actually stored, so using it unset copies past the buffer (heap-buffer-overflow) and sizes a binary larger than its allocation.