Re: [PATCH] tpm: fix potential NULL pointer access in tpm_del_char_device()

From: Lino Sanfilippo
Date: Fri Sep 24 2021 - 10:18:02 EST

On 24.09.21 at 15:33, Jason Gunthorpe wrote:
> On Fri, Sep 24, 2021 at 03:29:46PM +0200, Lino Sanfilippo wrote:
>> So this bug is triggered when the bcm2835 drivers shutdown() function is called since this
>> driver does something quite unusual: it unregisters the spi controller in its shutdown()
>> handler.
> This seems wrong
> Jason

Unregistering the SPI controller during shutdown is only a side-effect of calling
bcm2835_spi_remove() in the shutdown handler:

static void bcm2835_spi_shutdown(struct platform_device *pdev)
int ret;

ret = bcm2835_spi_remove(pdev);
if (ret)
dev_err(&pdev->dev, "failed to shutdown\n");