This is a note to let you know that I've just added the patch titled wifi: mac80211: mlme: fix non-inheritence element to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: wifi-mac80211-mlme-fix-non-inheritence-element.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ebee060550bb9a7cd532663e4277da89f6479631 Author: Johannes Berg <johannes.berg@xxxxxxxxx> Date: Sun Jun 4 12:11:16 2023 +0300 wifi: mac80211: mlme: fix non-inheritence element [ Upstream commit 68c228557d52616cf040651abefda9839de7086a ] There were two bugs when creating the non-inheritence element: 1) 'at_extension' needs to be declared outside the loop, otherwise the value resets every iteration and we can never really switch properly 2) 'added' never got set to true, so we always cut off the extension element again at the end of the function This shows another issue that we might add a list but no extension list, but we need to make the extension list a zero-length one in that case. Fix all these issues. While at it, add a comment explaining the trim. Fixes: 81151ce462e5 ("wifi: mac80211: support MLO authentication/association with one link") Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Gregory Greenman <gregory.greenman@xxxxxxxxx> Link: https://lore.kernel.org/r/20230604120651.3addaa5c4782.If3a78f9305997ad7ef4ba7ffc17a8234c956f613@changeid Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 0125b3e6175b7..dc9e7eb7dd857 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -1143,6 +1143,7 @@ static void ieee80211_add_non_inheritance_elem(struct sk_buff *skb, const u16 *inner) { unsigned int skb_len = skb->len; + bool at_extension = false; bool added = false; int i, j; u8 *len, *list_len = NULL; @@ -1154,7 +1155,6 @@ static void ieee80211_add_non_inheritance_elem(struct sk_buff *skb, for (i = 0; i < PRESENT_ELEMS_MAX && outer[i]; i++) { u16 elem = outer[i]; bool have_inner = false; - bool at_extension = false; /* should at least be sorted in the sense of normal -> ext */ WARN_ON(at_extension && elem < PRESENT_ELEM_EXT_OFFS); @@ -1183,8 +1183,14 @@ static void ieee80211_add_non_inheritance_elem(struct sk_buff *skb, } *list_len += 1; skb_put_u8(skb, (u8)elem); + added = true; } + /* if we added a list but no extension list, make a zero-len one */ + if (added && (!at_extension || !list_len)) + skb_put_u8(skb, 0); + + /* if nothing added remove extension element completely */ if (!added) skb_trim(skb, skb_len); else