From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 97A3024B28; Wed, 8 Apr 2026 18:32:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775673129; cv=none; b=TMcSpgXHEl2c5ylcx0v0WpGHOYTPZajQL8d0gyHpD00DGejOVIlUJ7GjA50dzbQvSxx3DN0ONgd3iLZ80lq3UmKA1NqG+SqCmydHEM5JvaRjAXqN4CYoReZKYRG3PrlBYzzEZOJKPzbb/M5IhI+YJRwbifFU0whiJgYfIvhEFU8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775673129; c=relaxed/simple; bh=5ByqjK9QpoPbGnjIJEA6QEakBDYYeHPPoJLsj/Z3V6c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=g5b+uk51k4wEbsHFBOQTuOhc6CS06b4W1zw1HSTHl1lf1pVFn41arfVgrggwritwUVPcKUtqze4gxVUuronnuK5UCAbnDmAS03C1VRmR2hM/3MgbpAKB9shDUkHM5myGXnbHnEOJez8FEXBasoOxHq0FkkuE8s/Yr/QQg75/aK8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cWdp0f46; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="cWdp0f46" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2D9B7C19421; Wed, 8 Apr 2026 18:32:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775673129; bh=5ByqjK9QpoPbGnjIJEA6QEakBDYYeHPPoJLsj/Z3V6c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cWdp0f46YgxQM88wNM54z+fHup+JKU/EabIm81f6WD8UFxP2T9eRhd8saTzGF7jx0 /yDxxc5oVKKnN5QAw+RVm7JejbJeDMvBRlxjerbNNrBEKHkUZEyTOBZEfeb7rTfjXi rY+iKBNjt4hyuUm3YsTKEe7qgzbTQQipEPYipBec= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jonathan Rissanen , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 6.18 080/277] Bluetooth: hci_h4: Fix race during initialization Date: Wed, 8 Apr 2026 20:01:05 +0200 Message-ID: <20260408175936.852002087@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260408175933.836769063@linuxfoundation.org> References: <20260408175933.836769063@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jonathan Rissanen [ Upstream commit 0ffac654e95c1bdfe2d4edf28fb18d6ba1f103e6 ] Commit 5df5dafc171b ("Bluetooth: hci_uart: Fix another race during initialization") fixed a race for hci commands sent during initialization. However, there is still a race that happens if an hci event from one of these commands is received before HCI_UART_REGISTERED has been set at the end of hci_uart_register_dev(). The event will be ignored which causes the command to fail with a timeout in the log: "Bluetooth: hci0: command 0x1003 tx timeout" This is because the hci event receive path (hci_uart_tty_receive -> h4_recv) requires HCI_UART_REGISTERED to be set in h4_recv(), while the hci command transmit path (hci_uart_send_frame -> h4_enqueue) only requires HCI_UART_PROTO_INIT to be set in hci_uart_send_frame(). The check for HCI_UART_REGISTERED was originally added in commit c2578202919a ("Bluetooth: Fix H4 crash from incoming UART packets") to fix a crash caused by hu->hdev being null dereferenced. That can no longer happen: once HCI_UART_PROTO_INIT is set in hci_uart_register_dev() all pointers (hu, hu->priv and hu->hdev) are valid, and hci_uart_tty_receive() already calls h4_recv() on HCI_UART_PROTO_INIT or HCI_UART_PROTO_READY. Remove the check for HCI_UART_REGISTERED in h4_recv() to fix the race condition. Fixes: 5df5dafc171b ("Bluetooth: hci_uart: Fix another race during initialization") Signed-off-by: Jonathan Rissanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- drivers/bluetooth/hci_h4.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/bluetooth/hci_h4.c b/drivers/bluetooth/hci_h4.c index ec017df8572c8..1e9e2cad9ddf6 100644 --- a/drivers/bluetooth/hci_h4.c +++ b/drivers/bluetooth/hci_h4.c @@ -109,9 +109,6 @@ static int h4_recv(struct hci_uart *hu, const void *data, int count) { struct h4_struct *h4 = hu->priv; - if (!test_bit(HCI_UART_REGISTERED, &hu->flags)) - return -EUNATCH; - h4->rx_skb = h4_recv_buf(hu, h4->rx_skb, data, count, h4_recv_pkts, ARRAY_SIZE(h4_recv_pkts)); if (IS_ERR(h4->rx_skb)) { -- 2.53.0