Re: [PATCH] octeon_ep: Add missing check for ioremap

From: Jakub Kicinski
Date: Wed Jun 14 2023 - 15:53:13 EST


On Wed, 14 Jun 2023 11:23:47 +0800 Jiasheng Jiang wrote:
> @@ -981,6 +981,9 @@ int octep_device_setup(struct octep_device *oct)
> oct->mmio[i].hw_addr =
> ioremap(pci_resource_start(oct->pdev, i * 2),
> pci_resource_len(oct->pdev, i * 2));
> + if (!oct->mmio[i].hw_addr)
> + goto unsupported_dev;
> +
> oct->mmio[i].mapped = 1;
> }
>
> @@ -1015,8 +1018,8 @@ int octep_device_setup(struct octep_device *oct)
> return 0;
>
> unsupported_dev:
> - for (i = 0; i < OCTEP_MMIO_REGIONS; i++)
> - iounmap(oct->mmio[i].hw_addr);
> + for (j = 0; j < i; j++)
> + iounmap(oct->mmio[j].hw_addr);

Assuming @i is not changed by the rest of the function is a bit fragile.

Better way of handling this situation is:

unsupported_dev:
i = OCTEP_MMIO_REGIONS;
unmap_prev:
while (i--)
iounmap(oct->mmio[i].hw_addr);

and jump to unmap_prev
--
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