Summary: | Certain large ping sizes are not forwarded properly | ||
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Product: | passt | Reporter: | David Gibson <dgibson> |
Component: | ICMP | Assignee: | nobody |
Status: | CONFIRMED --- | ||
Severity: | minor | ||
Priority: | Low | ||
Version: | unspecified | ||
Hardware: | All | ||
OS: | Linux | ||
Bug Depends on: | 65, 62 | ||
Bug Blocks: |
Description
David Gibson
2023-06-20 05:14:28 UTC
Ok, I've investigated this, and it appears to be a consequence of the fact that we don't handle IP fragmentation. ping -s 65492 is the largest ping size which can be sent unfragmented with our guest-side MTU of 65520 bytes. Beyond that the ping in the guest is fragmented, and because we don't handle defragmentation in passt/pasta, we only forward the contents of the first fragment to the ping socket, so the reply comes back similarly truncated. |