As the possible failure of the allocation, the devm_ioremap() may return NULL pointer. Then the kpspi->base is assigned to cs->base in kp_spi_setup() and used in kp_spi_read_reg() and kp_spi_write_reg(). Therefore, it should be better to add the sanity check and return error in order to avoid the dereference of the NULL pointer. Fixes: 677b993a5749 ("staging: kpc2000: kpc_spi: use devm_* API to manage mapped I/O space") Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx> --- drivers/staging/kpc2000/kpc2000_spi.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/staging/kpc2000/kpc2000_spi.c b/drivers/staging/kpc2000/kpc2000_spi.c index 16ca18b8aa15..ead4aa0c988c 100644 --- a/drivers/staging/kpc2000/kpc2000_spi.c +++ b/drivers/staging/kpc2000/kpc2000_spi.c @@ -466,6 +466,10 @@ kp_spi_probe(struct platform_device *pldev) kpspi->base = devm_ioremap(&pldev->dev, r->start, resource_size(r)); + if (!kpspi->base) { + status = -ENOMEM; + goto free_master; + } status = spi_register_master(master); if (status < 0) { -- 2.25.1