[PATCH AUTOSEL 4.4 1/9] cfg80211: call cfg80211_leave_ocb when switching away from OCB

From: Du Cheng <redacted>

[ Upstream commit a64b6a25dd9f984ed05fade603a00e2eae787d2f ]

If the userland switches back-and-forth between NL80211_IFTYPE_OCB and
NL80211_IFTYPE_ADHOC via send_msg(NL80211_CMD_SET_INTERFACE), there is a
chance where the cleanup cfg80211_leave_ocb() is not called. This leads
to initialization of in-use memory (e.g. init u.ibss while in-use by
u.ocb) due to a shared struct/union within ieee80211_sub_if_data:

struct ieee80211_sub_if_data {
    ...
    union {
        struct ieee80211_if_ap ap;
        struct ieee80211_if_vlan vlan;
        struct ieee80211_if_managed mgd;
        struct ieee80211_if_ibss ibss; // <- shares address
        struct ieee80211_if_mesh mesh;
        struct ieee80211_if_ocb ocb; // <- shares address
        struct ieee80211_if_mntr mntr;
        struct ieee80211_if_nan nan;
    } u;
    ...
}

Therefore add handling of otype == NL80211_IFTYPE_OCB, during
cfg80211_change_iface() to perform cleanup when leaving OCB mode.

link to syzkaller bug:
https://syzkaller.appspot.com/bug?id=0612dbfa595bf4b9b680ff7b4948257b8e3732d5

Reported-by: syzbot+105896fac213f26056f9@syzkaller.appspotmail.com
Signed-off-by: Du Cheng <redacted>
Link: https://lore.kernel.org/r/20210428063941.105161-1-ducheng2@gmail.com
Signed-off-by: Johannes Berg <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/wireless/util.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 915f1fa881e4..73c361fd4a16 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c

@@ -978,6 +978,9 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 		case NL80211_IFTYPE_MESH_POINT:
 			/* mesh should be handled? */
 			break;
+		case NL80211_IFTYPE_OCB:
+			cfg80211_leave_ocb(rdev, dev);
+			break;
 		default:
 			break;
 		}

-- 
2.30.2

From: Johannes Berg <redacted>

[ Upstream commit a9799541ca34652d9996e45f80e8e03144c12949 ]

These are not permitted by the spec, just drop them.

Link: https://lore.kernel.org/r/20210609161305.23def022b750.Ibd6dd3cdce573dae262fcdc47f8ac52b883a9c50@changeid
Signed-off-by: Johannes Berg <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/mac80211/rx.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index ae0fba044cd0..bde924968cd2 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c

@@ -1853,17 +1853,15 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 	sc = le16_to_cpu(hdr->seq_ctrl);
 	frag = sc & IEEE80211_SCTL_FRAG;
 
-	if (is_multicast_ether_addr(hdr->addr1)) {
-		I802_DEBUG_INC(rx->local->dot11MulticastReceivedFrameCount);
-		goto out_no_led;
-	}
-
 	if (rx->sta)
 		cache = &rx->sta->frags;
 
 	if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
 		goto out;
 
+	if (is_multicast_ether_addr(hdr->addr1))
+		return RX_DROP_MONITOR;
+
 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 
 	if (skb_linearize(rx->skb))

@@ -1992,7 +1990,6 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 
  out:
 	ieee80211_led_rx(rx->local);
- out_no_led:
 	if (rx->sta)
 		rx->sta->rx_stats.packets++;
 	return RX_CONTINUE;

-- 
2.30.2