Quoting Jonathan Cameron (2023-10-28 08:26:38) > On Thu, 26 Oct 2023 23:53:28 +0000 > Justin Stitt <justinstitt@xxxxxxxxxx> wrote: > > > We're doing some needless string copies when trying to assign the proper > > `prop` string. We can make `prop` a const char* and simply assign to > > string literals. > > > > For the case where a format string is used, let's allocate some memory > > via kasprintf() and point prop to it. > > > > This also cleans up some deprecated strncpy() uses [1]. > > > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] > > Link: https://github.com/KSPP/linux/issues/90 > > Cc: linux-hardening@xxxxxxxxxxxxxxx > > Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx> > > Seems reasonable to me. > > +CC Gwendal (+ Stephen) as it's Gwendal's driver and I think they are still actively > maintaining it. Thanks! I have some review comments. > > diff --git a/drivers/iio/proximity/sx9324.c b/drivers/iio/proximity/sx9324.c > > index 438f9c9aba6e..c8547035cb47 100644 > > --- a/drivers/iio/proximity/sx9324.c > > +++ b/drivers/iio/proximity/sx9324.c > > @@ -885,7 +885,7 @@ sx9324_get_default_reg(struct device *dev, int idx, > > #define SX9324_RESOLUTION_DEF "semtech,ph01-resolution" > > #define SX9324_PROXRAW_DEF "semtech,ph01-proxraw-strength" > > unsigned int pin_defs[SX9324_NUM_PINS]; > > - char prop[] = SX9324_PROXRAW_DEF; > > + const char *prop = SX9324_PROXRAW_DEF; Do we need this define anymore, or the initialization? > > u32 start = 0, raw = 0, pos = 0; > > int ret, count, ph, pin; > > const char *res; > > @@ -899,7 +899,7 @@ sx9324_get_default_reg(struct device *dev, int idx, > > case SX9324_REG_AFE_PH2: > > case SX9324_REG_AFE_PH3: > > ph = reg_def->reg - SX9324_REG_AFE_PH0; > > - snprintf(prop, ARRAY_SIZE(prop), "semtech,ph%d-pin", ph); > > + prop = kasprintf(GFP_KERNEL, "semtech,ph%d-pin", ph); Do we not care if the allocation fails? We just use the default? > > > > count = device_property_count_u32(dev, prop); > > if (count != ARRAY_SIZE(pin_defs)) > > @@ -913,6 +913,7 @@ sx9324_get_default_reg(struct device *dev, int idx, > > raw |= (pin_defs[pin] << (2 * pin)) & > > SX9324_REG_AFE_PH0_PIN_MASK(pin); > > reg_def->def = raw; > > + kfree(prop); We need to free it in other places too, like if the count doesn't match. It may be easier to extract this section and just have 4 string literals. switch (reg_def->reg) { case SX9324_REG_AFE_PH0: reg_def = sx9324_parse_phase_prop(dev, reg_def, "semtech,ph0-pin"); break; case SX9324_REG_AFE_PH1: reg_def = sx9324_parse_phase_prop(dev, reg_def, "semtech,ph1-pin"); break; case SX9324_REG_AFE_PH2: reg_def = sx9324_parse_phase_prop(dev, reg_def, "semtech,ph2-pin"); break; case SX9324_REG_AFE_PH3: reg_def = sx9324_parse_phase_prop(dev, reg_def, "semtech,ph3-pin"); break; > > case SX9324_REG_AFE_CTRL0: > > ret = device_property_read_string(dev,
