linux-kernel - [PATCH v2 7/8] Bluetooth: hci_conn: hold reference in abort_conn

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <0d75210630e1f71b18dfc5cd97610a41effb1789.1762100290.git.pav@iki.fi>
Date: Sun,  2 Nov 2025 18:19:39 +0200
From: Pauli Virtanen <pav@....fi>
To: linux-bluetooth@...r.kernel.org
Cc: Pauli Virtanen <pav@....fi>,
	marcel@...tmann.org,
	johan.hedberg@...il.com,
	luiz.dentz@...il.com,
	linux-kernel@...r.kernel.org
Subject: [PATCH v2 7/8] Bluetooth: hci_conn: hold reference in abort_conn_sync

hci_conn_valid() should not be used on potentially freed hci_conn
pointers, as relying on kmalloc not reusing addresses is bad practice.

Hold a hci_conn reference for the queue job so the pointer is not freed
too early.

This also avoids potential UAF during abort_conn_sync().

Signed-off-by: Pauli Virtanen <pav@....fi>
---

Notes:
    v2:
    - no change

 net/bluetooth/hci_conn.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 214fa6ec832b..64066f6a0af8 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -2956,6 +2956,13 @@ static int abort_conn_sync(struct hci_dev *hdev, void *data)
 	return hci_abort_conn_sync(hdev, conn, conn->abort_reason);
 }
 
+static void abort_conn_destroy(struct hci_dev *hdev, void *data, int err)
+{
+	struct hci_conn *conn = data;
+
+	hci_conn_put(conn);
+}
+
 int hci_abort_conn(struct hci_conn *conn, u8 reason)
 {
 	struct hci_dev *hdev = conn->hdev;
@@ -2996,7 +3003,10 @@ int hci_abort_conn(struct hci_conn *conn, u8 reason)
 	 * as a result to MGMT_OP_DISCONNECT/MGMT_OP_UNPAIR which does
 	 * already queue its callback on cmd_sync_work.
 	 */
-	err = hci_cmd_sync_run_once(hdev, abort_conn_sync, conn, NULL);
+	err = hci_cmd_sync_run_once(hdev, abort_conn_sync, hci_conn_get(conn),
+				    abort_conn_destroy);
+	if (err)
+		hci_conn_put(conn);
 	return (err == -EEXIST) ? 0 : err;
 }
 
-- 
2.51.1