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 AB97B3419D for ; Mon, 9 Oct 2023 13:52:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="MXmQWEW7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 21A4DC433C7; Mon, 9 Oct 2023 13:52:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1696859525; bh=mKo9Fff3LaYZrIBZ9fitj9/hMCL2XNBI9RIddaQD36g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MXmQWEW7aqqaVu8JWZqF4io9LnOfuaqILSDqV6PTuJsrBetOmvmeUXPZlm36PNVyJ WJc3rg2pJxmMoYt2/GDNiSb0i33YZiDt7IREr6MuPAJb7k4vuTiksk3Wst7M1QDsI1 Pj2Je7gehw25RIcs8/UY7hZ2y30umjgxYvEbRlT0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable , Andy Shevchenko , Florian Fainelli Subject: [PATCH 4.19 49/91] serial: 8250_port: Check IRQ data before use Date: Mon, 9 Oct 2023 15:06:21 +0200 Message-ID: <20231009130113.218157390@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231009130111.518916887@linuxfoundation.org> References: <20231009130111.518916887@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Shevchenko commit cce7fc8b29961b64fadb1ce398dc5ff32a79643b upstream. In case the leaf driver wants to use IRQ polling (irq = 0) and IIR register shows that an interrupt happened in the 8250 hardware the IRQ data can be NULL. In such a case we need to skip the wake event as we came to this path from the timer interrupt and quite likely system is already awake. Without this fix we have got an Oops: serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A ... BUG: kernel NULL pointer dereference, address: 0000000000000010 RIP: 0010:serial8250_handle_irq+0x7c/0x240 Call Trace: ? serial8250_handle_irq+0x7c/0x240 ? __pfx_serial8250_timeout+0x10/0x10 Fixes: 0ba9e3a13c6a ("serial: 8250: Add missing wakeup event reporting") Cc: stable Signed-off-by: Andy Shevchenko Reviewed-by: Florian Fainelli Link: https://lore.kernel.org/r/20230831222555.614426-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_port.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1910,7 +1910,10 @@ int serial8250_handle_irq(struct uart_po skip_rx = true; if (status & (UART_LSR_DR | UART_LSR_BI) && !skip_rx) { - if (irqd_is_wakeup_set(irq_get_irq_data(port->irq))) + struct irq_data *d; + + d = irq_get_irq_data(port->irq); + if (d && irqd_is_wakeup_set(d)) pm_wakeup_event(tport->tty->dev, 0); if (!up->dma || handle_rx_dma(up, iir)) status = serial8250_rx_chars(up, status);