From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA4F9C43334 for ; Fri, 24 Jun 2022 07:11:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229818AbiFXHLl (ORCPT ); Fri, 24 Jun 2022 03:11:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42108 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229523AbiFXHLk (ORCPT ); Fri, 24 Jun 2022 03:11:40 -0400 Received: from mail-pg1-x52a.google.com (mail-pg1-x52a.google.com [IPv6:2607:f8b0:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F27163631 for ; Fri, 24 Jun 2022 00:11:39 -0700 (PDT) Received: by mail-pg1-x52a.google.com with SMTP id g186so1629865pgc.1 for ; Fri, 24 Jun 2022 00:11:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=GN+qNt8Cw83f9WM+EZsvc9AedDf1YkE7NlHHQ95uLcg=; b=ZEe4hmibLxokNHF+BLv0iaiMAluCoPLanZmvFCppcyJTMa7gIHPFEyUS1MB1nrETCc AEDJRFU6g7ZnhHR4YCV9r18A1yhT1gOW2/2IkONUeeeG/a6CCzdx0RQbgWXmD/OMF8Ws YSuNnopDHTXHR8e0oOxroiNAOtQ+WH/aPbFzuCQtISbzYJQ4b4Rpq1Ku6jDJ5m8g5Kzz bnNSQ0suC18aSl5o1+Jcl3K3VSRIr6mucSYEaISBi36eZr5L3tLO3Wi2yZDIntv0642M EWdE8EkHFGW52GhQ55EX886lqS9ZDHSqHJ77MyvkobO7UlaUYP9WvUAwlAIhAcngJVxc Y80g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=GN+qNt8Cw83f9WM+EZsvc9AedDf1YkE7NlHHQ95uLcg=; b=ufOsdI14WCyq7LgkvY0+9K9OGn2mg/TtXw982xajn5h/0/Bjluvufk66Pw50Ley2rC mkxGacrxAvqEhlaFtz6Snti9NhYtP4sS1VWCM4wSj4hskdp7i4/+crPh8ysF/UMgwL+z muzy7e5xziuGQcU8SOcXPQ9ztRmhCq+R9iPcmHm+pHH3fDrnWhOlz9enzTnBqk2I4f4y +zfU701tPRq/bij6RDxPjy2UJgLOD8DQVOEDhCa7Fh5xt96WlUvbm/KqDCHGTSqmPWIA gmH/HiLVyIwLgIFdfbR/5IzXofjp6CqTRJXdhTt38XVEJ9UIwUqX/Oo/PCHPJa+QVdbF oNPA== X-Gm-Message-State: AJIora/98pZIxIfB8xV6w0JIQusUMT48T96BATwvOQJq77/rF87nMcqn 2mqJhfFWeKlWh+RXCcOPOuQl X-Google-Smtp-Source: AGRyM1u/gNiENA3t+nbnVjc6sbLb6II6uT478GqWAIfvVmlKCAY2eOh1ECiV1ZJQqh3w4zfOHGwJxA== X-Received: by 2002:a63:f256:0:b0:40d:5509:2126 with SMTP id d22-20020a63f256000000b0040d55092126mr5288029pgk.566.1656054698888; Fri, 24 Jun 2022 00:11:38 -0700 (PDT) Received: from thinkpad ([220.158.158.183]) by smtp.gmail.com with ESMTPSA id e30-20020a17090a6fa100b001eafa265869sm3155007pjk.56.2022.06.24.00.11.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Jun 2022 00:11:38 -0700 (PDT) Date: Fri, 24 Jun 2022 12:41:30 +0530 From: Manivannan Sadhasivam To: Marc Kleine-Budde Cc: linux-can@vger.kernel.org, kernel@pengutronix.de, Thomas Kopp Subject: Re: [PATCH] can: mcp251xfd: mcp251xfd_register_get_dev_id(): use correct length to read dev_id Message-ID: <20220624071130.GA11407@thinkpad> References: <20220616094914.244440-1-mkl@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220616094914.244440-1-mkl@pengutronix.de> Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org On Thu, Jun 16, 2022 at 11:49:14AM +0200, Marc Kleine-Budde wrote: > The device ID register is 32 bits wide. The driver uses incorrectly > the size of a pointer to a u32 to calculate the length of the SPI > transfer. This results in a read of 2 registers on 64 bit platforms. > This is no problem on the Linux side, as the RX buffer of the SPI > transfer is large enough. In the mpc251xfd chip this results in the > read of an undocumented register. So far no problems were observed. > > This patch fixes the length of the SPI transfer to read the device ID > register only. > > Fixes: 55e5b97f003e ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN") > Signed-off-by: Marc Kleine-Budde Reviewed-by: Manivannan Sadhasivam Thanks, Mani > --- > drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c > index 34b160024ce3..3160881e89d9 100644 > --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c > +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c > @@ -1778,7 +1778,7 @@ mcp251xfd_register_get_dev_id(const struct mcp251xfd_priv *priv, u32 *dev_id, > xfer[0].len = sizeof(buf_tx->cmd); > xfer[0].speed_hz = priv->spi_max_speed_hz_slow; > xfer[1].rx_buf = buf_rx->data; > - xfer[1].len = sizeof(dev_id); > + xfer[1].len = sizeof(*dev_id); > xfer[1].speed_hz = priv->spi_max_speed_hz_fast; > > mcp251xfd_spi_cmd_read_nocrc(&buf_tx->cmd, MCP251XFD_REG_DEVID); > -- > 2.35.1 > > -- மணிவண்ணன் சதாசிவம்