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 7DD0C2E54BB; Mon, 1 Dec 2025 11:29:55 +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=1764588595; cv=none; b=qB0oSENxiAzMAgsOWb433NU0G1tESEGSEG3u5iZMVxpyQinux5QIsAgxjy4uSW70YYKHIlaH0vIVdefowc+g8N6p/ucdsiZzBnl1pVsh4Ut+QZ7H0jwwEfSscVyjRxKEufVT64+nI8gEkMAVnzBGG3Q+9deuby8y25m/aZgqbR0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764588595; c=relaxed/simple; bh=MWbMk2yV8OrXFYad3NCcAIGhDpp0Y2aiUuqeszaEEl0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fvAXfhyUScyx2/rn3LgQE8bMAwDgy94AGox1LI9Yi1LLpOIipVXlS3+4I5eD8HobRBg0rxR/l2AEU2lK6V5nAjq4AoXYsaOis4Iljm0Yrush2mZnlItQd3IyQF0ZZ98T1krpPsZfotKMT05/HhHBWIwh7nfE7DZ52Lg9NxEb+uU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=sbzGyUyd; 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="sbzGyUyd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB61EC4CEF1; Mon, 1 Dec 2025 11:29:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1764588595; bh=MWbMk2yV8OrXFYad3NCcAIGhDpp0Y2aiUuqeszaEEl0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sbzGyUydsPNT+TAq4+zIwQeJP2dvhdXit/wnCetydswBbEQZfBT6KkKujOWsJ9+ZT 6jMJ9W6wsU4Okuos62Xk6j8CaTPyZky653dYZSWRs7QEsKgz9eGhCGPw2bWdRwrD9m Z4HMb8NAUj9GaBBDPCgI0/G3iQ0LizT5ecbH1Szk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+4ed6852d4da4606c93da@syzkaller.appspotmail.com, Ivan Pravdin , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 5.4 103/187] Bluetooth: bcsp: receive data only if registered Date: Mon, 1 Dec 2025 12:23:31 +0100 Message-ID: <20251201112244.958793095@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251201112241.242614045@linuxfoundation.org> References: <20251201112241.242614045@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 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ivan Pravdin [ Upstream commit ca94b2b036c22556c3a66f1b80f490882deef7a6 ] Currently, bcsp_recv() can be called even when the BCSP protocol has not been registered. This leads to a NULL pointer dereference, as shown in the following stack trace: KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f] RIP: 0010:bcsp_recv+0x13d/0x1740 drivers/bluetooth/hci_bcsp.c:590 Call Trace: hci_uart_tty_receive+0x194/0x220 drivers/bluetooth/hci_ldisc.c:627 tiocsti+0x23c/0x2c0 drivers/tty/tty_io.c:2290 tty_ioctl+0x626/0xde0 drivers/tty/tty_io.c:2706 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f To prevent this, ensure that the HCI_UART_REGISTERED flag is set before processing received data. If the protocol is not registered, return -EUNATCH. Reported-by: syzbot+4ed6852d4da4606c93da@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=4ed6852d4da4606c93da Tested-by: syzbot+4ed6852d4da4606c93da@syzkaller.appspotmail.com Signed-off-by: Ivan Pravdin Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- drivers/bluetooth/hci_bcsp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/bluetooth/hci_bcsp.c b/drivers/bluetooth/hci_bcsp.c index 8055f63603f45..8ff69111ceede 100644 --- a/drivers/bluetooth/hci_bcsp.c +++ b/drivers/bluetooth/hci_bcsp.c @@ -582,6 +582,9 @@ static int bcsp_recv(struct hci_uart *hu, const void *data, int count) struct bcsp_struct *bcsp = hu->priv; const unsigned char *ptr; + if (!test_bit(HCI_UART_REGISTERED, &hu->flags)) + return -EUNATCH; + BT_DBG("hu %p count %d rx_state %d rx_count %ld", hu, count, bcsp->rx_state, bcsp->rx_count); -- 2.51.0