4.19-stable review patch. If anyone has any objections, please let me know.
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From: Zhengping Jiang jiangzp@google.com
[ 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 fcc471f921895..9346fae5d664b 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5705,9 +5705,14 @@ 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);