CVE-2023-53658

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

spi: bcm-qspi: return error if neither hif_mspi nor mspi is available

If neither a "hif_mspi" nor "mspi" resource is present, the driver will

just early exit in probe but still return success. Apart from not doing

anything meaningful, this would then also lead to a null pointer access

on removal, as platform_get_drvdata() would return NULL, which it would

then try to dereference when trying to unregister the spi master.

Fix this by unconditionally calling devm_ioremap_resource(), as it can

handle a NULL res and will then return a viable ERR_PTR() if we get one.

The "return 0;" was previously a "goto qspi_resource_err;" where then

ret was returned, but since ret was still initialized to 0 at this place

this was a valid conversion in 63c5395bb7a9 ("spi: bcm-qspi: Fix

use-after-free on unbind"). The issue was not introduced by this commit,

only made more obvious.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References