Hi, On 18 October 2016 at 16:43, Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote: > mmc_regulator_get_supply might silently fail if the regulators are not > found, which is the right thing to do since both these regulators are > optional. > > However, the drivers then have no way to know whether or not they should > proceed and call mmc_regulator_set_ocr. And since this function doesn't > check for the validity of the regulator pointer, it leads to a null pointer > dereference. Add such a check to make sure everything works fine. > > Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> > --- > drivers/mmc/core/core.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > index 2553d903a82b..1d3ea5e1aa37 100644 > --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -1474,6 +1474,12 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc, > int result = 0; > int min_uV, max_uV; > > + if (!supply) > + return -EINVAL; > + > + if (IS_ERR(supply)) > + return PTR_ERR(supply); You can simply these checking with IS_ERR_OR_NULL(). > + > if (vdd_bit) { > mmc_ocrbitnum_to_vdd(vdd_bit, &min_uV, &max_uV); > > -- > 2.9.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Baolin.wang Best Regards -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html