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

[Hongling Zeng]

  Hi Sean,

  Thanks for the review! You're absolutely right about the incorrect 
Fixes: tag.

  Here's v3 with the correct Fixes tags pointing to the actual commits that
  introduced the resource leaks:

  - ee5bb35d2b83 introduced the pcim_iomap_region() direct return
  - 222606f43b58 introduced the devm_kmemdup() direct return

  Thanks again for catching that.

  Regards,
  Hongling


在 2026年05月27日 12:48, Sean Wang 写道:
> 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