CVE-2023-53242

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

thermal/drivers/hisi: Drop second sensor hi3660

The commit 74c8e6bffbe1 ("driver core: Add __alloc_size hint to devm allocators") exposes a panic "BRK handler: Fatal exception" on the hi3660_thermal_probe funciton. This is because the function allocates memory for only one sensors array entry, but tries to fill up a second one.

Fix this by removing the unneeded second access.

A flaw was found in the Linux kernel's HiSilicon hi3660 thermal driver. The hi3660_thermal_probe() function allocates memory for only one entry of the sensors array but attempts to populate a second entry, resulting in an out-of-bounds write beyond the allocated buffer that triggers a kernel panic ("BRK handler: Fatal exception"). The issue was exposed by upstream commit 74c8e6bffbe1 ("driver core: Add __alloc_size hint to devm allocators"), which added allocation-size verification to devm allocators. Red Hat assesses this flaw as Low severity (CVSS 4.4, AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H): exploitation requires local access with high privileges, and the impact is limited to system availability, with no confidentiality or integrity impact. This is lower than the upstream CVE record's score of 7.1, which claims confidentiality and integrity impacts that are not supported by the technical evidence. In Red Hat Enterprise Linux 9, both the kernel and kernel-rt are affected; the fix has been deferred given the Low impact rating and the narrow conditions required to trigger the panic, which occurs only during driver probe on systems using the HiSilicon hi3660 thermal hardware, so the residual risk of deferring is a boot-time kernel panic (availability impact) on such systems. Red Hat Enterprise Linux 6, 7, 8, and 10, and Red Hat In-Vehicle OS are not affected because the vulnerable code is not present in those releases.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.