On Tue, Oct 17, 2023 at 11:41:58AM -0700, Nathan Chancellor wrote:
> With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
> indirect call targets are validated against the expected function
> pointer prototype to make sure the call target is valid to help mitigate
> ROP attacks. If they are not identical, there is a failure at run time,
> which manifests as either a kernel panic or thread getting killed. A
> warning in clang aims to catch these at compile time, which reveals:
>
> drivers/pci/controller/dwc/pcie-rcar-gen4.c:403:15: error: incompatible function pointer types initializing 'int (*)(struct dw_pcie_ep *, u8, enum pci_epc_irq_type, u16)' (aka 'int (*)(struct dw_pcie_ep *, unsigned char, enum pci_epc_irq_type, unsigned sort)') with an expression of type 'int (struct dw_pcie_ep *, u8, unsigned int, u16)' (aka 'int (struct dw_pcie_ep *, unsigned char, unsigned int, unsigned short)') [-Werror,-Wincompatible-function-pointer-types-strict]
> 403 | .raise_irq = rcar_gen4_pcie_ep_raise_irq,
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> 1 error generated.
>
> '->raise_irq()' in 'struct dw_pcie_ep_ops' expects a type parameter of
> type 'enum pci_epc_irq_type', not 'unsigned int'. Adjust the type to
> match and use the proper enum values in the switch. The underlying value
> of both the enum and the macro is the same, so there is no functional
> change while clearing up the warning and avoiding a CFI failure at run
> time.
>
> Fixes: 32b83c68d634 ("PCI: rcar-gen4: Add endpoint mode support")
> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Thanks, Nathan.
Yoshihiro, can you fold this in on the next rev of your rcar-gen4
series?
I dropped the rcar-gen4 branch for today since it broke Marek's system
(Samsung Exynos5433-based TM2e board), so when we fix that we should
be able to fold in this fix at the same time.
> ---
> drivers/pci/controller/dwc/pcie-rcar-gen4.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index 619262d32f4e..0c0f5c257b14 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -353,14 +353,15 @@ static void rcar_gen4_pcie_ep_deinit(struct dw_pcie_ep *ep)
> }
>
> static int rcar_gen4_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
> - unsigned int type, u16 interrupt_num)
> + enum pci_epc_irq_type type,
> + u16 interrupt_num)
> {
> struct dw_pcie *dw = to_dw_pcie_from_ep(ep);
>
> switch (type) {
> - case PCI_IRQ_LEGACY:
> + case PCI_EPC_IRQ_LEGACY:
> return dw_pcie_ep_raise_legacy_irq(ep, func_no);
> - case PCI_IRQ_MSI:
> + case PCI_EPC_IRQ_MSI:
> return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
> default:
> dev_err(dw->dev, "Unknown IRQ type\n");
>
> ---
> base-commit: de45624e69e14ccd6b4b2886155578bb218925de
> change-id: 20231017-pcie-rcar-wifpts-6c65df6f8c8b
>
> Best regards,
> --
> Nathan Chancellor <nathan@xxxxxxxxxx>
>
