From fe49aa73cca6608714477b74bfc6874b9db979df Mon Sep 17 00:00:00 2001 From: Zhengping Jiang <jiangzp@google.com> Date: Wed, 24 May 2023 17:04:15 -0700 Subject: [PATCH] Bluetooth: L2CAP: Fix use-after-free [ Upstream commit f752a0b334bb95fe9b42ecb511e0864e2768046f ] Fix potential use-after-free in l2cap_le_command_rej. Signed-off-by: Zhengping Jiang <jiangzp@google.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- net/bluetooth/l2cap_core.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index e56863587ea2..61bf48926550 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5723,9 +5723,14 @@ static inline int l2cap_le_command_rej(struct l2cap_conn *conn, if (!chan) goto done; + chan = l2cap_chan_hold_unless_zero(chan); + if (!chan) + goto done; + l2cap_chan_lock(chan); l2cap_chan_del(chan, ECONNREFUSED); l2cap_chan_unlock(chan); + l2cap_chan_put(chan); done: mutex_unlock(&conn->chan_lock);