5.15-stable review patch. If anyone has any objections, please let me know.
------------------ From: Justin Stitt <[email protected]> [ Upstream commit b0009b8bed98bd5d59449af48781703df261c247 ] 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: [email protected] Signed-off-by: Justin Stitt <[email protected]> Reviewed-by: Kees Cook <[email protected]> Link: https://lore.kernel.org/r/20231020-strncpy-drivers-power-supply-bq24190_charger-c-v1-1-e896223cb...@google.com Signed-off-by: Sebastian Reichel <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- drivers/power/supply/bq24190_charger.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/power/supply/bq24190_charger.c b/drivers/power/supply/bq24190_charger.c index 90ac5e59a5d6f..8a4729ee1ab19 100644 --- a/drivers/power/supply/bq24190_charger.c +++ b/drivers/power/supply/bq24190_charger.c @@ -1727,7 +1727,7 @@ 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->f_reg = 0; bdi->ss_reg = BQ24190_REG_SS_VBUS_STAT_MASK; /* impossible state */ -- 2.43.0
