From: Jeongjun Park <aha310510@gmail.com>
To: Johannes Berg <johannes@sipsolutions.net>
Cc: linux-wireless@vger.kernel.org,
syzbot+81cd9dc1596563141d19@syzkaller.appspotmail.com,
linux-kernel@vger.kernel.org, Jeongjun Park <aha310510@gmail.com>
Subject: [PATCH] wifi: mac80211: fix NULL pointer dereference in ieee80211_mesh_build_beacon()
Date: Tue, 20 Jan 2026 00:00:31 +0900 [thread overview]
Message-ID: <20260119150031.201832-1-aha310510@gmail.com> (raw)
NULL pointer dereference bug occurs because ieee80211_mesh_build_beacon()
does not check the return value of ieee80211_get_sband().
Therefore, we need to add a return value check to prevent this.
Reported-by: syzbot+81cd9dc1596563141d19@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/696e34bf.a70a0220.34546f.04ad.GAE@google.com/
Fixes: 147ceae20534 ("wifi: mac80211: simplify adding supported rates")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
---
net/mac80211/mesh.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index 68901f1def0d..eb3a346226bd 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -964,6 +964,8 @@ ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
sband = ieee80211_get_sband(sdata);
+ if (!sband)
+ return -EINVAL;
ie_len_he_cap = ieee80211_ie_len_he_cap(sdata);
ie_len_eht_cap = ieee80211_ie_len_eht_cap(sdata);
--
next reply other threads:[~2026-01-19 15:02 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-19 15:00 Jeongjun Park [this message]
2026-01-20 8:12 ` [PATCH] wifi: mac80211: fix NULL pointer dereference in ieee80211_mesh_build_beacon() Johannes Berg
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