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From:   John Crispin <john@phrozen.org>
To:     Johannes Berg <johannes@sipsolutions.net>
Cc:     linux-wireless@vger.kernel.org, John Crispin <john@phrozen.org>,
        Dan Carpenter <dan.carpenter@oracle.com>
Subject: [PATCH] mac80211: fix possible NULL pointerderef in obss pd code
Date:   Tue, 13 Aug 2019 09:07:12 +0200
Message-Id: <20190813070712.25509-1-john@phrozen.org>
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Sender: linux-wireless-owner@vger.kernel.org
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he_spr_ie_elem is dereferenced before the NULL check. fix this by moving
the assignment after the check.

fixes commit 697f6c507c74 ("mac80211: propagate HE operation info into
bss_conf")

This was reported by the static code checker.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Crispin <john@phrozen.org>
---
 net/mac80211/he.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/mac80211/he.c b/net/mac80211/he.c
index a02abfc424aa..736da0035135 100644
--- a/net/mac80211/he.c
+++ b/net/mac80211/he.c
@@ -72,12 +72,13 @@ ieee80211_he_spr_ie_to_bss_conf(struct ieee80211_vif *vif,
 {
 	struct ieee80211_he_obss_pd *he_obss_pd =
 					&vif->bss_conf.he_obss_pd;
-	const u8 *data = he_spr_ie_elem->optional;
+	const u8 *data;
 
 	memset(he_obss_pd, 0, sizeof(*he_obss_pd));
 
 	if (!he_spr_ie_elem)
 		return;
+	data = he_spr_ie_elem->optional;
 
 	if (he_spr_ie_elem->he_sr_control &
 	    IEEE80211_HE_SPR_NON_SRG_OFFSET_PRESENT)
-- 
2.20.1