From: Ryan Lin Date: Fri, 30 Jan 2026 05:34:56 +0000 (+0800) Subject: HID: intel-ish-hid: fix NULL-ptr-deref in ishtp_bus_remove_all_clients X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=56f7db581ee73af53cd512e00a6261a025bf1d58;p=thirdparty%2Fkernel%2Flinux.git HID: intel-ish-hid: fix NULL-ptr-deref in ishtp_bus_remove_all_clients During a warm reset flow, the cl->device pointer may be NULL if the reset occurs while clients are still being enumerated. Accessing cl->device->reference_count without a NULL check leads to a kernel panic. This issue was identified during multi-unit warm reboot stress clycles. Add a defensive NULL check for cl->device to ensure stability under such intensive testing conditions. KASAN: null-ptr-deref in range [0000000000000000-0000000000000007] Workqueue: ish_fw_update_wq fw_reset_work_fn Call Trace: ishtp_bus_remove_all_clients+0xbe/0x130 [intel_ishtp] ishtp_reset_handler+0x85/0x1a0 [intel_ishtp] fw_reset_work_fn+0x8a/0xc0 [intel_ish_ipc] Fixes: 3703f53b99e4a ("HID: intel_ish-hid: ISH Transport layer") Signed-off-by: Ryan Lin Signed-off-by: Jiri Kosina --- diff --git a/drivers/hid/intel-ish-hid/ishtp/bus.c b/drivers/hid/intel-ish-hid/ishtp/bus.c index c3915f3a060ea..b890fbf97a75c 100644 --- a/drivers/hid/intel-ish-hid/ishtp/bus.c +++ b/drivers/hid/intel-ish-hid/ishtp/bus.c @@ -730,7 +730,7 @@ void ishtp_bus_remove_all_clients(struct ishtp_device *ishtp_dev, spin_lock_irqsave(&ishtp_dev->cl_list_lock, flags); list_for_each_entry(cl, &ishtp_dev->cl_list, link) { cl->state = ISHTP_CL_DISCONNECTED; - if (warm_reset && cl->device->reference_count) + if (warm_reset && cl->device && cl->device->reference_count) continue; /*