Hi Colin,
On Fri, 2019-11-08 at 15:55 +0000, Colin King wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> Function syscon_regmap_lookup_by_compat can return a NULL pointer, so
Could you point out where that NULL pointer would come from? As far as I
understand, syscon_regmap_lookup_by_compatible() should either return a
negative error code, or syscon->regmap, which should never be NULL.
> the IS_ERR check on the return is incorrect. Fix this by checking for
> IS_ERR_OR_NULL and return -ENODEV if true. This avoids a null pointer
> dereference on gcr_regmap later on.
>
> Addresses-Coverity: ("Dereference null return (stat)")
> Fixes: b3f1d036f26d ("reset: npcm: add NPCM reset controller driver")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
> drivers/reset/reset-npcm.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/reset/reset-npcm.c b/drivers/reset/reset-npcm.c
> index 2ea4d3136e15..9febf8bed2f6 100644
> --- a/drivers/reset/reset-npcm.c
> +++ b/drivers/reset/reset-npcm.c
> @@ -161,9 +161,9 @@ static int npcm_usb_reset(struct platform_device *pdev, struct npcm_rc_data *rc)
> of_match_device(dev->driver->of_match_table, dev)->data;
>
> gcr_regmap = syscon_regmap_lookup_by_compatible(gcr_dt);
> - if (IS_ERR(gcr_regmap)) {
> + if (IS_ERR_OR_NULL(gcr_regmap)) {
> dev_err(&pdev->dev, "Failed to find %s\n", gcr_dt);
> - return PTR_ERR(gcr_regmap);
> + return -ENODEV;
> }
>
> /* checking which USB device is enabled */
regards
Philipp
