FAILED: patch "[PATCH] Bluetooth: hci_event: fix potential UAF in SSP passkey" failed to apply to 5.15-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 85fa3512048793076eef658f66489112dcc91993
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026050440-overlaid-handpick-7fc8@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 85fa3512048793076eef658f66489112dcc91993 Mon Sep 17 00:00:00 2001
From: Shuvam Pandey <shuvampandey1@gmail.com>
Date: Thu, 9 Apr 2026 00:32:30 +0545
Subject: [PATCH] Bluetooth: hci_event: fix potential UAF in SSP passkey
 handlers

hci_conn lookup and field access must be covered by hdev lock in
hci_user_passkey_notify_evt() and hci_keypress_notify_evt(), otherwise
the connection can be freed concurrently.

Extend the hci_dev_lock critical section to cover all conn usage in both
handlers.

Keep the existing keypress notification behavior unchanged by routing
the early exits through a common unlock path.

Fixes: 92a25256f142 ("Bluetooth: mgmt: Implement support for passkey notification")
Cc: stable@vger.kernel.org
Signed-off-by: Shuvam Pandey <shuvampandey1@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 83248085dd4f..b2ee6b6a0f56 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -5495,9 +5495,11 @@ static void hci_user_passkey_notify_evt(struct hci_dev *hdev, void *data,
 
 	bt_dev_dbg(hdev, "");
 
+	hci_dev_lock(hdev);
+
 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &ev->bdaddr);
 	if (!conn)
-		return;
+		goto unlock;
 
 	conn->passkey_notify = __le32_to_cpu(ev->passkey);
 	conn->passkey_entered = 0;
@@ -5506,6 +5508,9 @@ static void hci_user_passkey_notify_evt(struct hci_dev *hdev, void *data,
 		mgmt_user_passkey_notify(hdev, &conn->dst, conn->type,
 					 conn->dst_type, conn->passkey_notify,
 					 conn->passkey_entered);
+
+unlock:
+	hci_dev_unlock(hdev);
 }
 
 static void hci_keypress_notify_evt(struct hci_dev *hdev, void *data,
@@ -5516,14 +5521,16 @@ static void hci_keypress_notify_evt(struct hci_dev *hdev, void *data,
 
 	bt_dev_dbg(hdev, "");
 
+	hci_dev_lock(hdev);
+
 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &ev->bdaddr);
 	if (!conn)
-		return;
+		goto unlock;
 
 	switch (ev->type) {
 	case HCI_KEYPRESS_STARTED:
 		conn->passkey_entered = 0;
-		return;
+		goto unlock;
 
 	case HCI_KEYPRESS_ENTERED:
 		conn->passkey_entered++;
@@ -5538,13 +5545,16 @@ static void hci_keypress_notify_evt(struct hci_dev *hdev, void *data,
 		break;
 
 	case HCI_KEYPRESS_COMPLETED:
-		return;
+		goto unlock;
 	}
 
 	if (hci_dev_test_flag(hdev, HCI_MGMT))
 		mgmt_user_passkey_notify(hdev, &conn->dst, conn->type,
 					 conn->dst_type, conn->passkey_notify,
 					 conn->passkey_entered);
+
+unlock:
+	hci_dev_unlock(hdev);
 }
 
 static void hci_simple_pair_complete_evt(struct hci_dev *hdev, void *data,