hid_report: fall back to boot extractor when NKRO extraction fails#338
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ibrahim1416 wants to merge 1 commit into
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hid_report: fall back to boot extractor when NKRO extraction fails#338ibrahim1416 wants to merge 1 commit into
ibrahim1416 wants to merge 1 commit into
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Some wireless dongles (e.g. Lemokey Link, VID 0x362d PID 0xd030) advertise an NKRO collection in their HID descriptor but actually transmit standard boot-style keyboard reports: a 1-byte report ID followed by 8 bytes of [modifier, reserved, 6 keycodes]. The descriptor's NKRO bitmap dimensions do not match the actual report layout, so _extract_kbd_nkro() returns -1. Previously, extract_kbd_data() did not check the return value and the caller proceeded with a zeroed report — so the keyboard appeared to be working at the USB level but no keys were ever forwarded. This change makes extract_kbd_data() fall through to the boot extractor when NKRO extraction fails. The "8 bytes optionally prefixed with a report ID" branch also drops the !iface->uses_report_id condition so it can catch report-ID'd boot-style reports (len == 9). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
Some wireless dongles (observed on a Lemokey Link, VID
0x362dPID0xd030) advertise an NKRO collection in their HID report descriptor but actually transmit standard boot-style keyboard reports — a 1-byte report ID followed by[modifier, reserved, 6 keycodes](total 9 bytes).Because the descriptor's parsed NKRO bitmap dimensions don't match the actual report layout,
_extract_kbd_nkro()returns-1.extract_kbd_data()was not checking this return value, soprocess_keyboard_report()continued with a zeroed report. The result: the keyboard interface enumerates fine, reports arrive at the host every keystroke, but no keys are ever forwarded.Changes
extract_kbd_data()now falls through to the next extractor when_extract_kbd_nkro()returns-1, clearing the partially-filled report first.!iface->uses_report_idguard so it can catch report-ID-prefixed boot reports (len == 9).Test plan
is_nkrois false.🤖 Generated with Claude Code