CVE-2024-38664

/// Technical description

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

drm: zynqmp_dpsub: Always register bridge

We must always register the DRM bridge, since zynqmp_dp_hpd_work_func

calls drm_bridge_hpd_notify, which in turn expects hpd_mutex to be

initialized. We do this before zynqmp_dpsub_drm_init since that calls

drm_bridge_attach. This fixes the following lockdep warning:

[ 19.217084] ------------[ cut here ]------------

[ 19.227530] DEBUG_LOCKS_WARN_ON(lock->magic != lock)

[ 19.227768] WARNING: CPU: 0 PID: 140 at kernel/locking/mutex.c:582 __mutex_lock+0x4bc/0x550

[ 19.241696] Modules linked in:

[ 19.244937] CPU: 0 PID: 140 Comm: kworker/0:4 Not tainted 6.6.20+ #96

[ 19.252046] Hardware name: xlnx,zynqmp (DT)

[ 19.256421] Workqueue: events zynqmp_dp_hpd_work_func

[ 19.261795] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)

[ 19.269104] pc : __mutex_lock+0x4bc/0x550

[ 19.273364] lr : __mutex_lock+0x4bc/0x550

[ 19.277592] sp : ffffffc085c5bbe0

/// 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