From 2c2fb2411198b997ba2613bff49ec8cc60ddb511 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Sat, 15 Dec 2018 11:03:12 +0200 Subject: [PATCH] mac80211: fix radiotap vendor presence bitmap handling [ Upstream commit efc38dd7d5fa5c8cdd0c917c5d00947aa0539443 ] Due to the alignment handling, it actually matters where in the code we add the 4 bytes for the presence bitmap to the length; the first field is the timestamp with 8 byte alignment so we need to add the space for the extra vendor namespace presence bitmap *before* we do any alignment for the fields. Move the presence bitmap length accounting to the right place to fix the alignment for the data properly. Signed-off-by: Johannes Berg Signed-off-by: Luca Coelho Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/mac80211/rx.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 9e19ddb..c7ac1a4 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -141,6 +141,9 @@ ieee80211_rx_radiotap_hdrlen(struct ieee80211_local *local, /* allocate extra bitmaps */ if (status->chains) len += 4 * hweight8(status->chains); + /* vendor presence bitmap */ + if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) + len += 4; if (ieee80211_have_rx_timestamp(status)) { len = ALIGN(len, 8); @@ -182,8 +185,6 @@ ieee80211_rx_radiotap_hdrlen(struct ieee80211_local *local, if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) { struct ieee80211_vendor_radiotap *rtap = (void *)skb->data; - /* vendor presence bitmap */ - len += 4; /* alignment for fixed 6-byte vendor data header */ len = ALIGN(len, 2); /* vendor data header */ -- 2.7.4