From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932686AbbIYRGR (ORCPT ); Fri, 25 Sep 2015 13:06:17 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:33988 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932234AbbIYRGP (ORCPT ); Fri, 25 Sep 2015 13:06:15 -0400 Date: Fri, 25 Sep 2015 18:06:12 +0100 From: Lee Jones To: Grigoryev Denis Cc: "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v5] mfd: tps6105x: Fix possible NULL pointer access. Message-ID: <20150925170612.GK27197@x1> References: <1E0B3F54A97F2C4591427D8CCF3028AD691D8CFF@SPB-PRIMARY-1.spb.prosoft.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1E0B3F54A97F2C4591427D8CCF3028AD691D8CFF@SPB-PRIMARY-1.spb.prosoft.ru> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 25 Sep 2015, Grigoryev Denis wrote: > tps6105 driver provides two cells. One is for GPIO and another one is > for selected mode depending on platform data. When tps6105x is used in > GPIO-only mode, this driver calls mfd_add_devices() with mfd_cell > .name == NULL. This value causes an oops in platform_device_register() > later. > > The following patch adds a mfd_cell for each possible mode thereby > excluding .name assignment in runtime. > > Signed-off-by: Denis Grigoryev > --- > drivers/mfd/tps6105x.c | 72 +++++++++++++++++++++++++++++------------------- > 1 file changed, 43 insertions(+), 29 deletions(-) Applied, thanks. > diff --git a/drivers/mfd/tps6105x.c b/drivers/mfd/tps6105x.c > index 5de95c2..182ebe0 100644 > --- a/drivers/mfd/tps6105x.c > +++ b/drivers/mfd/tps6105x.c > @@ -119,27 +119,47 @@ static int tps6105x_startup(struct tps6105x *tps6105x) > } > > /* > - * MFD cells - we have one cell which is selected operation > - * mode, and we always have a GPIO cell. > + * MFD cells - we always have a GPIO cell and we have one cell > + * which is selected operation mode. > */ > -static struct mfd_cell tps6105x_cells[] = { > - { > - /* name will be runtime assigned */ > - .id = -1, > - }, > - { > - .name = "tps6105x-gpio", > - .id = -1, > - }, > +static struct mfd_cell tps6105x_gpio_cell = { > + .name = "tps6105x-gpio", > +}; > + > +static struct mfd_cell tps6105x_leds_cell = { > + .name = "tps6105x-leds", > +}; > + > +static struct mfd_cell tps6105x_flash_cell = { > + .name = "tps6105x-flash", > }; > > +static struct mfd_cell tps6105x_regulator_cell = { > + .name = "tps6105x-regulator", > +}; > + > +static int tps6105x_add_device(struct tps6105x *tps6105x, > + struct mfd_cell *cell) > +{ > + cell->platform_data = tps6105x; > + cell->pdata_size = sizeof(*tps6105x); > + > + return mfd_add_devices(&tps6105x->client->dev, > + PLATFORM_DEVID_AUTO, cell, 1, NULL, 0, NULL); > +} > + > static int tps6105x_probe(struct i2c_client *client, > const struct i2c_device_id *id) > { > struct tps6105x *tps6105x; > struct tps6105x_platform_data *pdata; > int ret; > - int i; > + > + pdata = dev_get_platdata(&client->dev); > + if (!pdata) { > + dev_err(&client->dev, "missing platform data\n"); > + return -ENODEV; > + } > > tps6105x = devm_kmalloc(&client->dev, sizeof(*tps6105x), GFP_KERNEL); > if (!tps6105x) > @@ -147,7 +167,6 @@ static int tps6105x_probe(struct i2c_client *client, > > i2c_set_clientdata(client, tps6105x); > tps6105x->client = client; > - pdata = dev_get_platdata(&client->dev); > tps6105x->pdata = pdata; > mutex_init(&tps6105x->lock); > > @@ -157,38 +176,33 @@ static int tps6105x_probe(struct i2c_client *client, > return ret; > } > > - /* Remove warning texts when you implement new cell drivers */ > + ret = tps6105x_add_device(tps6105x, &tps6105x_gpio_cell); > + if (ret) > + return ret; > + > switch (pdata->mode) { > case TPS6105X_MODE_SHUTDOWN: > dev_info(&client->dev, > "present, not used for anything, only GPIO\n"); > break; > case TPS6105X_MODE_TORCH: > - tps6105x_cells[0].name = "tps6105x-leds"; > - dev_warn(&client->dev, > - "torch mode is unsupported\n"); > + ret = tps6105x_add_device(tps6105x, &tps6105x_leds_cell); > break; > case TPS6105X_MODE_TORCH_FLASH: > - tps6105x_cells[0].name = "tps6105x-flash"; > - dev_warn(&client->dev, > - "flash mode is unsupported\n"); > + ret = tps6105x_add_device(tps6105x, &tps6105x_flash_cell); > break; > case TPS6105X_MODE_VOLTAGE: > - tps6105x_cells[0].name ="tps6105x-regulator"; > + ret = tps6105x_add_device(tps6105x, &tps6105x_regulator_cell); > break; > default: > + dev_warn(&client->dev, "invalid mode: %d\n", pdata->mode); > break; > } > > - /* Set up and register the platform devices. */ > - for (i = 0; i < ARRAY_SIZE(tps6105x_cells); i++) { > - /* One state holder for all drivers, this is simple */ > - tps6105x_cells[i].platform_data = tps6105x; > - tps6105x_cells[i].pdata_size = sizeof(*tps6105x); > - } > + if (ret) > + mfd_remove_devices(&client->dev); > > - return mfd_add_devices(&client->dev, 0, tps6105x_cells, > - ARRAY_SIZE(tps6105x_cells), NULL, 0, NULL); > + return ret; > } > > static int tps6105x_remove(struct i2c_client *client) -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog