Re: [PATCH] tty: serdev: serdev-ttyport: add devt for ctrl->dev
From: Dan Carpenter
Date: Mon Mar 20 2023 - 01:56:04 EST
Hi Sherry,
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Sherry-Sun/tty-serdev-serdev-ttyport-add-devt-for-ctrl-dev/20230315-185913
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
patch link: https://lore.kernel.org/r/20230315105400.23426-1-sherry.sun%40nxp.com
patch subject: [PATCH] tty: serdev: serdev-ttyport: add devt for ctrl->dev
config: x86_64-randconfig-m001 (https://download.01.org/0day-ci/archive/20230316/202303160201.bnmM2caW-lkp@xxxxxxxxx/config)
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Reported-by: Dan Carpenter <error27@xxxxxxxxx>
| Link: https://lore.kernel.org/r/202303160201.bnmM2caW-lkp@xxxxxxxxx/
smatch warnings:
drivers/tty/serdev/serdev-ttyport.c:273 serdev_tty_port_register() warn: variable dereferenced before check 'drv' (see line 270)
vim +/drv +273 drivers/tty/serdev/serdev-ttyport.c
bed35c6dfa6a36 Rob Herring 2017-02-02 264 struct device *serdev_tty_port_register(struct tty_port *port,
bed35c6dfa6a36 Rob Herring 2017-02-02 265 struct device *parent,
bed35c6dfa6a36 Rob Herring 2017-02-02 266 struct tty_driver *drv, int idx)
bed35c6dfa6a36 Rob Herring 2017-02-02 267 {
bed35c6dfa6a36 Rob Herring 2017-02-02 268 struct serdev_controller *ctrl;
bed35c6dfa6a36 Rob Herring 2017-02-02 269 struct serport *serport;
225acc66b125b9 Sherry Sun 2023-03-15 @270 dev_t devt = MKDEV(drv->major, drv->minor_start) + idx;
^^^^^ ^^^^^
Dereferences.
bed35c6dfa6a36 Rob Herring 2017-02-02 271 int ret;
bed35c6dfa6a36 Rob Herring 2017-02-02 272
bed35c6dfa6a36 Rob Herring 2017-02-02 @273 if (!port || !drv || !parent)
^^^^
Checked too late. Are these checks really required?
bed35c6dfa6a36 Rob Herring 2017-02-02 274 return ERR_PTR(-ENODEV);
bed35c6dfa6a36 Rob Herring 2017-02-02 275
bed35c6dfa6a36 Rob Herring 2017-02-02 276 ctrl = serdev_controller_alloc(parent, sizeof(struct serport));
bed35c6dfa6a36 Rob Herring 2017-02-02 277 if (!ctrl)
bed35c6dfa6a36 Rob Herring 2017-02-02 278 return ERR_PTR(-ENOMEM);
bed35c6dfa6a36 Rob Herring 2017-02-02 279 serport = serdev_controller_get_drvdata(ctrl);
bed35c6dfa6a36 Rob Herring 2017-02-02 280
bed35c6dfa6a36 Rob Herring 2017-02-02 281 serport->port = port;
bed35c6dfa6a36 Rob Herring 2017-02-02 282 serport->tty_idx = idx;
bed35c6dfa6a36 Rob Herring 2017-02-02 283 serport->tty_drv = drv;
bed35c6dfa6a36 Rob Herring 2017-02-02 284
225acc66b125b9 Sherry Sun 2023-03-15 285 ctrl->dev.devt = devt;
bed35c6dfa6a36 Rob Herring 2017-02-02 286 ctrl->ops = &ctrl_ops;
bed35c6dfa6a36 Rob Herring 2017-02-02 287
aee5da7838787f Johan Hovold 2017-04-11 288 port->client_ops = &client_ops;
aee5da7838787f Johan Hovold 2017-04-11 289 port->client_data = ctrl;
aee5da7838787f Johan Hovold 2017-04-11 290
bed35c6dfa6a36 Rob Herring 2017-02-02 291 ret = serdev_controller_add(ctrl);
bed35c6dfa6a36 Rob Herring 2017-02-02 292 if (ret)
aee5da7838787f Johan Hovold 2017-04-11 293 goto err_reset_data;
bed35c6dfa6a36 Rob Herring 2017-02-02 294
bed35c6dfa6a36 Rob Herring 2017-02-02 295 dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx);
bed35c6dfa6a36 Rob Herring 2017-02-02 296 return &ctrl->dev;
bed35c6dfa6a36 Rob Herring 2017-02-02 297
aee5da7838787f Johan Hovold 2017-04-11 298 err_reset_data:
aee5da7838787f Johan Hovold 2017-04-11 299 port->client_data = NULL;
0c5aae59270fb1 Johan Hovold 2020-02-10 300 port->client_ops = &tty_port_default_client_ops;
bed35c6dfa6a36 Rob Herring 2017-02-02 301 serdev_controller_put(ctrl);
aee5da7838787f Johan Hovold 2017-04-11 302
bed35c6dfa6a36 Rob Herring 2017-02-02 303 return ERR_PTR(ret);
bed35c6dfa6a36 Rob Herring 2017-02-02 304 }
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests