Device: Netgear EX7300
Target: ath79/generic, mips_24kc
Version: OpenWrt 25.12.3 r32912-6639b15f62
When flow_offloading is enabled, fw4 reload causes nft to segfault.
Kernel log:
do_page_fault(): sending SIGSEGV to nft for invalid read access from 00000029
fw4 -v reload output:
add flowtable inet fw4 ft { hook ingress priority filter; devices = { "br-lan", "phy0-sta0" }; counter; }
add rule inet fw4 input iif "lo" accept comment "!fw4: Accept traffic from loopback"
Segmentation fault
GitHub issue: https://github.com/openwrt/openwrt/issues/23247
Symptom: Network speed randomly drops without any obvious reason.
Many users may think it's WiFi interference or ISP issue.
Root cause: nft crashes when fw4 loads flowtable rules,
causing flow offloading to fail silently. Speed drops significantly
when this happens.
Affected: Multiple platforms (ath79, mt7621, filogic),
multiple versions (24.10.x, 25.12.x).
GitHub issue: https://github.com/openwrt/openwrt/issues/23247
If you experience random speed drops, check if flowtable is loaded:
nft list flowtables
If empty, run: fw4 reload