From 3e4697ffdfbb38a2755012c4e571546c89ab6422 Mon Sep 17 00:00:00 2001
From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Mon, 31 Oct 2022 16:10:52 -0700
Subject: [PATCH] Bluetooth: L2CAP: Fix attempting to access uninitialized
memory
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commit b1a2cd50c0357f243b7435a732b4e62ba3157a2e upstream.
On l2cap_parse_conf_req the variable efs is only initialized if
remote_efs has been set.
CVE: CVE-2022-42895
CC: stable@vger.kernel.org
Reported-by: Tamás Koczka <poprdi@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/bluetooth/l2cap_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index a66c272a11f6..16f954a4802c 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -3764,7 +3764,8 @@ done:
l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
- if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
+ if (remote_efs &&
+ test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
chan->remote_id = efs.id;
chan->remote_stype = efs.stype;
chan->remote_msdu = le16_to_cpu(efs.msdu);