[PATCH AUTOSEL 6.4 31/41] wifi: cfg80211: reject auth/assoc to AP with our address

Sasha Levin
2023-09-08T18:21:05Z

From: Johannes Berg <johannes.berg@intel.com>

[ Upstream commit 5d4e04bf3a0f098bd9033de3a5291810fa14c7a6 ]

If the AP uses our own address as its MLD address or BSSID, then
clearly something's wrong. Reject such connections so we don't
try and fail later.

Reported-by: syzbot+2676771ed06a6df166ad@syzkaller.appspotmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/wireless/mlme.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index ac059cefbeb39..775cac4d61006 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -281,6 +281,11 @@ int cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
ether_addr_equal(req->bss->bssid, wdev->u.client.connected_addr))
return -EALREADY;

+ if (ether_addr_equal(req->bss->bssid, dev->dev_addr) ||
+ (req->link_id >= 0 &&
+ ether_addr_equal(req->ap_mld_addr, dev->dev_addr)))
+ return -EINVAL;
+
return rdev_auth(rdev, dev, req);
}

@@ -335,6 +340,9 @@ int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
if (req->links[i].bss == req->links[j].bss)
return -EINVAL;
}
+
+ if (ether_addr_equal(req->links[i].bss->bssid, dev->dev_addr))
+ return -EINVAL;
}

if (wdev->connected &&
@@ -342,6 +350,11 @@ int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
!ether_addr_equal(wdev->u.client.connected_addr, req->prev_bssid)))
return -EALREADY;

+ if ((req->bss && ether_addr_equal(req->bss->bssid, dev->dev_addr)) ||
+ (req->link_id >= 0 &&
+ ether_addr_equal(req->ap_mld_addr, dev->dev_addr)))
+ return -EINVAL;
+
cfg80211_oper_and_ht_capa(&req->ht_capa_mask,
rdev->wiphy.ht_capa_mod_mask);
cfg80211_oper_and_vht_capa(&req->vht_capa_mask,
--
2.40.1