Linux Kernel EUVD-2026-59384

CoreSight is ARM's hardware tracing and debugging subsystem (ETM sources, funnels, ETB sinks, etc.) managed in the Linux kernel under drivers/hwtracing/coresight/. The vulnerability is in coresight-platform.c, specifically coresight_add_out_conn() and coresight_add_in_conn(), which build the inter-component connection graph during device probe. These functions use device-managed allocators devm_krealloc_array() and devm_kmalloc(); when either returns NULL on ENOMEM, the functions return -ENOMEM up the stack to coresight_get_platform_data(), which then calls coresight_release_platform_data() for cleanup. That cleanup function iterates unconditionally up to the nr_outconns or nr_inconns counter value and dereferences each array entry - but because the counter was incremented prior to the failed allocation, at least one entry is NULL or uninitialized, causing a NULL pointer dereference kernel panic. While no CWE is formally assigned, this maps structurally to CWE-476 (NULL Pointer Dereference) caused by a premature counter increment logic error. The fix defers both counter increments to after all allocations succeed, ensuring struct consistency on every error path.