Re: [PATCH] wifi: ath11k: fix resource leak on error in ext IRQ setup

[Baochen Qiang <baochen.qiang@oss.qualcomm.com>]

On 6/22/2026 10:56 AM, ZhaoJinming wrote:
> In ath11k_ahb_config_irq(), when a CE request_irq() fails, the function
> returns the error immediately without freeing the CE IRQs that were
> successfully registered in previous loop iterations. The probe error
> path does not call ath11k_ahb_free_irq() either, so the previously
> registered CE IRQ handlers remain attached to the interrupt lines and
> are never released.
> 
> In ath11k_ahb_config_ext_irq(), when an external request_irq() fails,
> the error is only logged and the loop continues. The function then
> returns 0 indicating success, leaving the device in a partially
> configured state where some external IRQs are not registered. This
> causes enable_irq()/disable_irq()/free_irq() to be called on
> unregistered IRQs during runtime and remove/shutdown, triggering
> WARN_ON(!desc->action), and missing interrupt handlers lead to data
> loss.
> 
> Additionally, if alloc_netdev_dummy() fails for a later IRQ group, the
> function returns -ENOMEM without freeing the ext IRQs and napi_ndev
> that were successfully set up for earlier groups.
> 
> Fix all three issues: propagate the error up to the caller and unwind
> all successfully registered IRQs and allocated resources on failure.
> 
> Signed-off-by: ZhaoJinming <zhaojinming@uniontech.com>
> ---
>  drivers/net/wireless/ath/ath11k/ahb.c | 30 ++++++++++++++++++++++++---
>  1 file changed, 27 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath11k/ahb.c b/drivers/net/wireless/ath/ath11k/ahb.c
> index f566d699d074..041c0fefe8c8 100644
> --- a/drivers/net/wireless/ath/ath11k/ahb.c
> +++ b/drivers/net/wireless/ath/ath11k/ahb.c
> @@ -536,8 +536,10 @@ static int ath11k_ahb_config_ext_irq(struct ath11k_base *ab)
>  		irq_grp->grp_id = i;
>  
>  		irq_grp->napi_ndev = alloc_netdev_dummy(0);
> -		if (!irq_grp->napi_ndev)
> -			return -ENOMEM;
> +		if (!irq_grp->napi_ndev) {
> +			irq_grp->num_irq = 0;
> +			goto err_request_irq;
> +		}
>  
>  		netif_napi_add(irq_grp->napi_ndev, &irq_grp->napi,
>  			       ath11k_ahb_ext_grp_napi_poll);
> @@ -600,11 +602,25 @@ static int ath11k_ahb_config_ext_irq(struct ath11k_base *ab)
>  			if (ret) {
>  				ath11k_err(ab, "failed request_irq for %d\n",
>  					   irq);
> +				irq_grp->num_irq = j;
> +				goto err_request_irq;
>  			}
>  		}
>  	}
>  
>  	return 0;
> +
> +err_request_irq:
> +	for ( ; i >= 0; i--) {
> +		irq_grp = &ab->ext_irq_grp[i];

this does not compile since irq_grp is a local variable defined inside the for loop above.

> +		for (j = irq_grp->num_irq - 1; j >= 0; j--)
> +			free_irq(ab->irq_num[irq_grp->irqs[j]], irq_grp);
> +		if (irq_grp->napi_ndev) {
> +			netif_napi_del(&irq_grp->napi);
> +			free_netdev(irq_grp->napi_ndev);
> +		}
> +	}
> +	return ret;
>  }
>  
>  static int ath11k_ahb_config_irq(struct ath11k_base *ab)
> @@ -629,8 +645,16 @@ static int ath11k_ahb_config_irq(struct ath11k_base *ab)
>  		ret = request_irq(irq, ath11k_ahb_ce_interrupt_handler,
>  				  IRQF_TRIGGER_RISING, irq_name[irq_idx],
>  				  ce_pipe);
> -		if (ret)
> +		if (ret) {
> +			ath11k_err(ab, "failed request_irq for %d\n", irq);
> +			for (i--; i >= 0; i--) {
> +				if (ath11k_ce_get_attr_flags(ab, i) & CE_ATTR_DIS_INTR)
> +					continue;
> +				free_irq(ab->irq_num[ATH11K_IRQ_CE0_OFFSET + i],
> +					 &ab->ce.ce_pipe[i]);
> +			}
>  			return ret;
> +		}
>  
>  		ab->irq_num[irq_idx] = irq;
>  	}