Fix ARP lookups for gateway address when destination is outside of subnet #1248
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LGTM. Thank you! |
moninom1
approved these changes
May 7, 2025
aggarg
approved these changes
May 7, 2025
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Description
While egress packets that are destined to addresses outside of the endpoint's subnet are routed to the gateway, and, if the gateway address happens to be missing from the ARP cache, the ARP lookup for the gateway was performed on incorrect address (the original address to which the packet was destined) instead of the gateway address, leading to the ARP lookup to fail as the target address is outside of the subnet.
Thanks @nwf for reporting this issue in #1244.
This issue is now fixed by passing the correct address to the code that performs the ARP lookup of the gateway.
Test Steps
Tested on STM32F4 by verifying whether the ARP table gets populated with gateway address entry when a packet is sent outside of the subnet.
Checklist:
[ ] I have modified and/or added unit-tests to cover the code changes in this Pull Request.Related Issue
#1244
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