Re: [PATCH v2] wifi: mt76: mt7921: fix resource leak in probe error path

[Sean Wang]

Hi,

On Tue, May 26, 2026 at 10:44 PM Hongling Zeng <zenghongling@xxxxxxxxxx> wrote:
>
> When pcim_iomap_region() or devm_kmemdup() fail, the code returns
> directly without cleaning up previously allocated resources:
>   - mt76_device allocated by mt76_alloc_device()
>   - pci irq vectors allocated by pci_alloc_irq_vectors()
> Fix this by jumping to the existing error cleanup path instead of
> returning directly.
>
> To avoid using an uninitialized variable in the error path, move the
> dev initialization before the error checks.
>
> Fixes: 234738ea3390 ("phy: ti-pipe3: move clk initialization to a separate function")
> Signed-off-by: Hongling Zeng <zenghongling@xxxxxxxxxx>
>

The code change itself looks correct, but commit message Fixes: tag is wrong.

It points to 234738ea3390 ("phy: ti-pipe3: move clk initialization to
a separate function"), which is unrelated to mt76/mt7921.

The two direct-return leaks appear to come from:
      - ee5bb35d2b83 ("wifi: mt76: mt7921: Replace deprecated PCI
function") for the pcim_iomap_region() path.
      - 222606f43b58 ("wifi: mt76: mt7921: handle MT7902 irq_map quirk
with mutable copy") for the MT7902 devm_kmemdup() path.

> ---
>  Change in v1
>    --fix uninitialized variable warning
> ---
>  drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
> index 7a790ddf43bb..49a37185f056 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
> @@ -343,11 +343,14 @@ static int mt7921_pci_probe(struct pci_dev *pdev,
>
>         pci_set_drvdata(pdev, mdev);
>
> +       dev = container_of(mdev, struct mt792x_dev, mt76);
> +
>         regs =  pcim_iomap_region(pdev, 0, pci_name(pdev));
> -       if (IS_ERR(regs))
> -               return PTR_ERR(regs);
> +       if (IS_ERR(regs)) {
> +               ret = PTR_ERR(regs);
> +               goto err_free_dev;
> +       }
>
> -       dev = container_of(mdev, struct mt792x_dev, mt76);
>         dev->fw_features = features;
>         dev->hif_ops = &mt7921_pcie_ops;
>         dev->irq_map = &irq_map;
> @@ -359,8 +362,10 @@ static int mt7921_pci_probe(struct pci_dev *pdev,
>                 /* MT7902 needs a mutable copy because wm2_complete_mask differs */
>                 map = devm_kmemdup(&pdev->dev, &irq_map,
>                                    sizeof(irq_map), GFP_KERNEL);
> -               if (!map)
> -                       return -ENOMEM;
> +               if (!map) {
> +                       ret = -ENOMEM;
> +                       goto err_free_dev;
> +               }
>
>                 map->rx.wm2_complete_mask = 0;
>                 dev->irq_map = map;
> --
> 2.25.1
>
>