[PATCH net v2 0/2] tcp: re-enable acceptance of FIN packets when RWIN is 0
From: Simon Baatz via B4 Relay
Date: Tue Feb 24 2026 - 03:20:52 EST
Hi,
this series restores the ability to accept in‑sequence FIN packets
even when the advertised receive window is zero, and adds a
packetdrill test to guard the behavior.
Signed-off-by: Simon Baatz <gmbnomis@xxxxxxxxx>
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Changes in v2:
- Move the FIN handling out of the default execution path as suggested by Eric Dumazet
- Link to v1: https://lore.kernel.org/r/20260222-fix_zero_wnd_fin-v1-0-5f4034952f3c@xxxxxxxxx
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Simon Baatz (2):
tcp: re-enable acceptance of FIN packets when RWIN is 0
selftests/net: packetdrill: Verify acceptance of FIN packets when RWIN is 0
net/ipv4/tcp_input.c | 18 +++++++++++----
.../net/packetdrill/tcp_rcv_zero_wnd_fin.pkt | 27 ++++++++++++++++++++++
2 files changed, 41 insertions(+), 4 deletions(-)
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base-commit: d4f687fbbce45b5e88438e89b5e26c0c15847992
change-id: 20260221-fix_zero_wnd_fin-d1ba11cd3b07
Best regards,
--
Simon Baatz <gmbnomis@xxxxxxxxx>