Several functions in this file are trying to use regmap_read() to initialize the specific variable, however, if regmap_read() fails, the variable could be uninitialized but used directly, which is potentially unsafe. The return value of regmap_read() should be checked and handled. The same case also happens in function max17042_thread_handler() but it needs more effort to patch.
Signed-off-by: Yizhuo <yzhai...@ucr.edu> --- drivers/power/supply/max17042_battery.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/power/supply/max17042_battery.c b/drivers/power/supply/max17042_battery.c index e6a2dacaa730..b897776a2749 100644 --- a/drivers/power/supply/max17042_battery.c +++ b/drivers/power/supply/max17042_battery.c @@ -675,8 +675,12 @@ static void max17042_reset_vfsoc0_reg(struct max17042_chip *chip) { unsigned int vfSoc; struct regmap *map = chip->regmap; + int ret; + + ret = regmap_read(map, MAX17042_VFSOC, &vfSoc); + if (ret) + return; - regmap_read(map, MAX17042_VFSOC, &vfSoc); regmap_write(map, MAX17042_VFSOC0Enable, VFSOC0_UNLOCK); max17042_write_verify_reg(map, MAX17042_VFSOC0, vfSoc); regmap_write(map, MAX17042_VFSOC0Enable, VFSOC0_LOCK); @@ -686,12 +690,18 @@ static void max17042_load_new_capacity_params(struct max17042_chip *chip) { u32 full_cap0, rep_cap, dq_acc, vfSoc; u32 rem_cap; + int ret; struct max17042_config_data *config = chip->pdata->config_data; struct regmap *map = chip->regmap; - regmap_read(map, MAX17042_FullCAP0, &full_cap0); - regmap_read(map, MAX17042_VFSOC, &vfSoc); + ret = regmap_read(map, MAX17042_FullCAP0, &full_cap0); + if (ret) + return; + + ret = regmap_read(map, MAX17042_VFSOC, &vfSoc); + if (ret) + return; /* fg_vfSoc needs to shifted by 8 bits to get the * perc in 1% accuracy, to get the right rem_cap multiply @@ -1108,7 +1118,12 @@ static int max17042_probe(struct i2c_client *client, if (!client->irq) regmap_write(chip->regmap, MAX17042_SALRT_Th, 0xff00); - regmap_read(chip->regmap, MAX17042_STATUS, &val); + ret = regmap_read(chip->regmap, MAX17042_STATUS, &val); + if (ret) { + dev_err(&client->dev, "Failed to get MAX17042_STATUS.\n"); + return ret; + } + if (val & STATUS_POR_BIT) { INIT_WORK(&chip->work, max17042_init_worker); ret = devm_add_action(&client->dev, max17042_stop_work, chip); -- 2.17.1