From 20388c8d1d74c203fec8194c45cd31afdfab934e Mon Sep 17 00:00:00 2001 From: Fan Wu Date: Tue, 8 Sep 2026 04:17:39 +0000 Subject: [PATCH] usb: gadget: aspeed-vhub: cancel wake work on device removal wake_work is armed from the gadget .wakeup callback to resume suspended downstream ports, and it is never cancelled in ast_vhub_remove(), so a work item queued before or during removal can run after devm has freed vhub and its ports, a use-after-free. Cancelling the work alone is not sufficient: usb_gadget_wakeup() takes no lock and the unbind path never clears wakeup_en, so a remote-wakeup request in flight on another CPU can re-arm the work after the cancel and before vhub is freed. ast_vhub_del_dev() already clears d->registered under vhub->lock before unregistering the gadget. Refuse the wakeup in ast_vhub_udc_wakeup() once d->registered is clear: the check and the schedule_work() are then atomic against the unbind, so a wakeup that passed before the flag was cleared is drained by the cancel_work_sync() after the del_dev loop, and one that arrives later returns without arming. Also move INIT_WORK() to the top of ast_vhub_probe(), since the probe error path reuses ast_vhub_remove() and would otherwise cancel a never-initialized work item. This issue was found by an in-house static analysis tool. Fixes: 7ecca2a4080c ("usb/gadget: Add driver for Aspeed SoC virtual hub") Cc: stable@kernel.org Assisted-by: Codex:gpt-5.6 Co-developed-by: Song Li Signed-off-by: Song Li Signed-off-by: Fan Wu Reviewed-by: Benjamin Herrenschmidt Link: https://patch.msgid.link/20260908041740.613713-1-fanwu01@zju.edu.cn Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/udc/aspeed-vhub/core.c | 4 ++++ drivers/usb/gadget/udc/aspeed-vhub/dev.c | 2 +- drivers/usb/gadget/udc/aspeed-vhub/hub.c | 5 +++-- drivers/usb/gadget/udc/aspeed-vhub/vhub.h | 1 + 4 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/usb/gadget/udc/aspeed-vhub/core.c b/drivers/usb/gadget/udc/aspeed-vhub/core.c index 4a8b9ff8368f..069673f0d359 100644 --- a/drivers/usb/gadget/udc/aspeed-vhub/core.c +++ b/drivers/usb/gadget/udc/aspeed-vhub/core.c @@ -267,6 +267,9 @@ static void ast_vhub_remove(struct platform_device *pdev) for (i = 0; i < vhub->max_ports; i++) ast_vhub_del_dev(&vhub->ports[i].dev); + /* Final drain; the worker takes vhub->lock, so stay outside of it */ + cancel_work_sync(&vhub->wake_work); + spin_lock_irqsave(&vhub->lock, flags); /* Mask & ack all interrupts */ @@ -328,6 +331,7 @@ static int ast_vhub_probe(struct platform_device *pdev) return -ENOMEM; spin_lock_init(&vhub->lock); + INIT_WORK(&vhub->wake_work, ast_vhub_wake_work); vhub->pdev = pdev; vhub->port_irq_mask = GENMASK(VHUB_IRQ_DEV1_BIT + vhub->max_ports - 1, VHUB_IRQ_DEV1_BIT); diff --git a/drivers/usb/gadget/udc/aspeed-vhub/dev.c b/drivers/usb/gadget/udc/aspeed-vhub/dev.c index 8b9449d16324..4b389de0d935 100644 --- a/drivers/usb/gadget/udc/aspeed-vhub/dev.c +++ b/drivers/usb/gadget/udc/aspeed-vhub/dev.c @@ -280,7 +280,7 @@ static int ast_vhub_udc_wakeup(struct usb_gadget* gadget) int rc = -EINVAL; spin_lock_irqsave(&d->vhub->lock, flags); - if (!d->wakeup_en) + if (!d->wakeup_en || !d->registered) goto err; DDBG(d, "Device initiated wakeup\n"); diff --git a/drivers/usb/gadget/udc/aspeed-vhub/hub.c b/drivers/usb/gadget/udc/aspeed-vhub/hub.c index 02fe1a08d575..d0345f31037a 100644 --- a/drivers/usb/gadget/udc/aspeed-vhub/hub.c +++ b/drivers/usb/gadget/udc/aspeed-vhub/hub.c @@ -558,7 +558,7 @@ void ast_vhub_device_connect(struct ast_vhub *vhub, ast_vhub_send_host_wakeup(vhub); } -static void ast_vhub_wake_work(struct work_struct *work) +void ast_vhub_wake_work(struct work_struct *work) { struct ast_vhub *vhub = container_of(work, struct ast_vhub, @@ -588,6 +588,8 @@ static void ast_vhub_wake_work(struct work_struct *work) void ast_vhub_hub_wake_all(struct ast_vhub *vhub) { + lockdep_assert_held(&vhub->lock); + /* * A device is trying to wake the world, because this * can recurse into the device, we break the call chain @@ -1076,7 +1078,6 @@ static int ast_vhub_init_desc(struct ast_vhub *vhub) int ast_vhub_init_hub(struct ast_vhub *vhub) { vhub->speed = USB_SPEED_UNKNOWN; - INIT_WORK(&vhub->wake_work, ast_vhub_wake_work); return ast_vhub_init_desc(vhub); } diff --git a/drivers/usb/gadget/udc/aspeed-vhub/vhub.h b/drivers/usb/gadget/udc/aspeed-vhub/vhub.h index aca2050e2db0..96f1c3709042 100644 --- a/drivers/usb/gadget/udc/aspeed-vhub/vhub.h +++ b/drivers/usb/gadget/udc/aspeed-vhub/vhub.h @@ -547,6 +547,7 @@ void ast_vhub_hub_suspend(struct ast_vhub *vhub); void ast_vhub_hub_resume(struct ast_vhub *vhub); void ast_vhub_hub_reset(struct ast_vhub *vhub); void ast_vhub_hub_wake_all(struct ast_vhub *vhub); +void ast_vhub_wake_work(struct work_struct *work); /* dev.c */ int ast_vhub_init_dev(struct ast_vhub *vhub, unsigned int idx);