On Wed, 2024-10-23 at 11:35 +0300, Dan Carpenter wrote: > > The syscon_regmap_lookup_by_compatible() function returns -ENODEV if > there isn't a compatible for it or other error pointers on error. This > code only checks for -ENODEV instead of checking for other errors so it > could lead to an error pointer dereference inside the regmap_update_bits() > function. > > Fixes: ffcde9e44d3e ("drm: fsl-dcu: enable PIXCLK on LS1021A") > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Reviewed-by: Matthias Schiffer <matthias.schiffer@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c > index 91a48d774cf7..5997d9b4a431 100644 > --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c > +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c > @@ -109,7 +109,9 @@ static int fsl_dcu_load(struct drm_device *dev, unsigned long flags) > return dev_err_probe(dev->dev, ret, "failed to initialize mode setting\n"); > > scfg = syscon_regmap_lookup_by_compatible("fsl,ls1021a-scfg"); > - if (PTR_ERR(scfg) != -ENODEV) { > + if (IS_ERR(scfg) && PTR_ERR(scfg) != -ENODEV) > + return dev_err_probe(dev->dev, PTR_ERR(scfg), "failed to find regmap\n"); > + if (!IS_ERR(scfg)) { > /* > * For simplicity, enable the PIXCLK unconditionally, > * resulting in increased power consumption. Disabling -- TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht München, HRB 105018 Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider https://www.tq-group.com/