Affected: Linux

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

firmware: stratix10-rsu: Fix NULL pointer dereference when RSU is disabled

When the Remote System Update (RSU) isn't enabled in the First Stage Boot Loader (FSBL), the driver encounters a NULL pointer dereference when excute svc_normal_to_secure_thread() thread, resulting in a kernel panic:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 Mem abort info: ... Data abort info: ... [0000000000000008] user address but active_mm is swapper Internal error: Oops: 0000000096000004 [#1] SMP Modules linked in: CPU: 0 UID: 0 PID: 79 Comm: svc_smc_hvc_thr Not tainted 6.19.0-rc8-yocto-standard+ #59 PREEMPT Hardware name: SoCFPGA Stratix 10 SoCDK (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : svc_normal_to_secure_thread+0x38c/0x990 lr : svc_normal_to_secure_thread+0x144/0x990 ... Call trace: svc_normal_to_secure_thread+0x38c/0x990 (P) kthread+0x150/0x210 ret_from_fork+0x10/0x20 Code: 97cfc113 f9400260 aa1403e1 f9400400 (f9400402) ---[ end trace 0000000000000000 ]---

The issue occurs because rsu_send_async_msg() fails when RSU is not enabled in firmware, causing the channel to be freed via stratix10_svc_free_channel(). However, the probe function continues execution and registers svc_normal_to_secure_thread(), which subsequently attempts to access the already-freed channel, triggering the NULL pointer dereference.

Fix this by properly cleaning up the a…