Re: [PATCH wireless 0/1] wifi: mac80211: reset default-key debugfs after netdev recreate

[Johannes Berg <johannes@sipsolutions.net>]

On Mon, 2026-09-07 at 20:27 +0800, Zhiling Zou wrote:
> Hi Linux kernel maintainers,
> 
> We found and validated an issue in net/mac80211/debugfs_key.c and
> net/mac80211/debugfs_netdev.c. The bug is reachable by a root user.
> 
> We've tested it, and it should not affect any other functionality.
> 
> We will provide detailed information about the bug in this email, along
> with a PoC to trigger it.

[snip]

Did you read what your LLM wrote?


>     	printf("[4/7] add WEP40 group key idx 0\n");
>     	err = new_key(sock, family_id, ifindex, 0, wep40_key, sizeof(wep40_key));
>     	if (err < 0) {
>     		fprintf(stderr, "NL80211_CMD_NEW_KEY failed: %s (%d)\n",
>     			nl_geterror(err), err);
>     		return 1;
>     	}
>     
>     	printf("[5/7] set key idx 0 as the default key on the deflink\n");
>     	err = set_default_key(sock, family_id, ifindex, 0, -1);
>     	if (err < 0) {
>     		fprintf(stderr, "initial NL80211_CMD_SET_KEY failed: %s (%d)\n",
>     			nl_geterror(err), err);
>     		return 1;
>     	}
>     
>     	printf("[6/7] add MLO link 1; this recreates the netdev debugfs tree while the key stays alive\n");

Sure, WEP on MLO, but somehow debugfs is the problem ...

johannes