From db878e27a98106a70315d264cc92230d84009e72 Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@intel.com>
Date: Thu, 8 Apr 2021 14:31:50 +0200
Subject: [PATCH] mac80211: bail out if cipher schemes are invalid
Git-commit: db878e27a98106a70315d264cc92230d84009e72
Patch-mainline: v5.13-rc1
References: git-fixes

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
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 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 1b9c82616606..0331f3a3c40e 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -1141,8 +1141,11 @@ 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)
-- 
2.26.2