[PATCH 5.10 407/530] mac80211: bail out if cipher schemes are invalid

From: Johannes Berg <redacted>

[ Upstream commit db878e27a98106a70315d264cc92230d84009e72 ]

If any of the cipher schemes specified by the driver are invalid, bail
out and fail the registration rather than just warning.  Otherwise, we
might later crash when we try to use the invalid cipher scheme, e.g.
if the hdr_len is (significantly) less than the pn_offs + pn_len, we'd
have an out-of-bounds access in RX validation.

Fixes: 2475b1cc0d52 ("mac80211: add generic cipher scheme support")
Link: https://lore.kernel.org/r/20210408143149.38a3a13a1b19.I6b7f5790fa0958ed8049cf02ac2a535c61e9bc96@changeid (local)
Signed-off-by: Johannes Berg <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/mac80211/main.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 19c093bb3876..73893025922f 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c

@@ -1150,8 +1150,11 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 	if (local->hw.wiphy->max_scan_ie_len)
 		local->hw.wiphy->max_scan_ie_len -= local->scan_ies_len;
 
-	WARN_ON(!ieee80211_cs_list_valid(local->hw.cipher_schemes,
-					 local->hw.n_cipher_schemes));
+	if (WARN_ON(!ieee80211_cs_list_valid(local->hw.cipher_schemes,
+					     local->hw.n_cipher_schemes))) {
+		result = -EINVAL;
+		goto fail_workqueue;
+	}
 
 	result = ieee80211_init_cipher_suites(local);
 	if (result < 0)

-- 
2.30.2