From: Justin Stitt Date: Fri, 20 Oct 2023 18:14:47 +0000 (+0000) Subject: power: supply: bq24190_charger: replace deprecated strncpy with strscpy X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=b0009b8bed98bd5d59449af48781703df261c247;p=linux.git power: supply: bq24190_charger: replace deprecated strncpy with strscpy strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. We expect bdi->model_name to be NUL-terminated based on its usage with sysfs_emit and format strings: val->strval is assigned to bdi->model_name in bq24190_charger_get_property(): 1186 | val->strval = bdi->model_name; ... then in power_supply_sysfs.c we use value.strval with a format string: 311 | ret = sysfs_emit(buf, "%s\n", value.strval); we assigned value.strval via: 285 | ret = power_supply_get_property(psy, psp, &value); ... which invokes psy->desc->get_property(): 1210 | return psy->desc->get_property(psy, psp, val); with bq24190_charger_get_property(): 1320 | static const struct power_supply_desc bq24190_charger_desc = { ... 1325 | .get_property = bq24190_charger_get_property, Moreover, no NUL-padding is required as bdi is zero-allocated in bq24190_charger.c: 1798 | bdi = devm_kzalloc(dev, sizeof(*bdi), GFP_KERNEL); Considering the above, a suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on the destination buffer without unnecessarily NUL-padding. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2] Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@vger.kernel.org Signed-off-by: Justin Stitt Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20231020-strncpy-drivers-power-supply-bq24190_charger-c-v1-1-e896223cb795@google.com Signed-off-by: Sebastian Reichel --- diff --git a/drivers/power/supply/bq24190_charger.c b/drivers/power/supply/bq24190_charger.c index 3f99cb9590ba2..1db290ee2591a 100644 --- a/drivers/power/supply/bq24190_charger.c +++ b/drivers/power/supply/bq24190_charger.c @@ -1803,7 +1803,7 @@ static int bq24190_probe(struct i2c_client *client) bdi->client = client; bdi->dev = dev; - strncpy(bdi->model_name, id->name, I2C_NAME_SIZE); + strscpy(bdi->model_name, id->name, sizeof(bdi->model_name)); mutex_init(&bdi->f_reg_lock); bdi->charge_type = POWER_SUPPLY_CHARGE_TYPE_FAST; bdi->f_reg = 0;