From 4bdee8060d1e4581624e68fbd369b1afb14df4bc Mon Sep 17 00:00:00 2001 From: Myeonghun Pak Date: Mon, 21 Sep 2026 20:09:14 -0400 Subject: [PATCH] net: airoha: npu: cancel wdt_work after releasing the WDT IRQ airoha_npu_remove() calls cancel_work_sync() on each core's wdt_work, but the watchdog IRQ that queues it is requested with devm_request_irq() and is freed only after .remove() returns. airoha_npu_wdt_handler() can therefore schedule_work() again once the cancel has returned. struct airoha_npu, which contains the work, is devm_kzalloc()'d and is freed in that same unwind, so the late work dereferences freed memory. Register the work with devm_work_autocancel() before devm_request_irq() and drop .remove(). Devres runs in reverse order, so the IRQ is freed before cancel_work_sync(), including when probe fails. A cancel left in .remove() cannot get that order. Initializing the work first also stops a pending watchdog interrupt from queuing an uninitialized work item. Probe currently calls INIT_WORK() only after devm_request_irq(). This issue was identified during our ongoing static-analysis research while reviewing kernel code. Fixes: 23290c7bc190 ("net: airoha: Introduce Airoha NPU support") Cc: stable@vger.kernel.org # 6.15+ Co-developed-by: Ijae Kim Signed-off-by: Ijae Kim Signed-off-by: Myeonghun Pak Acked-by: Lorenzo Bianconi Link: https://patch.msgid.link/20260922000914.542068-1-mhun512@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/airoha/airoha_npu.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/airoha/airoha_npu.c b/drivers/net/ethernet/airoha/airoha_npu.c index 5bb4817a898d..4d3195eb00f7 100644 --- a/drivers/net/ethernet/airoha/airoha_npu.c +++ b/drivers/net/ethernet/airoha/airoha_npu.c @@ -5,6 +5,7 @@ */ #include +#include #include #include #include @@ -751,12 +752,15 @@ static int airoha_npu_probe(struct platform_device *pdev) if (irq < 0) return irq; + err = devm_work_autocancel(dev, &core->wdt_work, + airoha_npu_wdt_work); + if (err) + return err; + err = devm_request_irq(dev, irq, airoha_npu_wdt_handler, IRQF_SHARED, "airoha-npu-wdt", core); if (err) return err; - - INIT_WORK(&core->wdt_work, airoha_npu_wdt_work); } /* wlan IRQ lines */ @@ -803,18 +807,8 @@ static int airoha_npu_probe(struct platform_device *pdev) return 0; } -static void airoha_npu_remove(struct platform_device *pdev) -{ - struct airoha_npu *npu = platform_get_drvdata(pdev); - int i; - - for (i = 0; i < ARRAY_SIZE(npu->cores); i++) - cancel_work_sync(&npu->cores[i].wdt_work); -} - static struct platform_driver airoha_npu_driver = { .probe = airoha_npu_probe, - .remove = airoha_npu_remove, .driver = { .name = "airoha-npu", .of_match_table = of_airoha_npu_match,