Unverified Commit f015b53d authored by Niklas Cassel's avatar Niklas Cassel Committed by Krzysztof Wilczyński
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PCI: endpoint: Add size check for fixed size BARs in pci_epc_set_bar() 

A BAR of type BAR_FIXED has a fixed BAR size (the size cannot be changed).

When using pci_epf_alloc_space() to allocate backing memory for a BAR,
pci_epf_alloc_space() will always set the size to the fixed BAR size if
the BAR type is BAR_FIXED (and will give an error if you the requested size
is larger than the fixed BAR size).

However, some drivers might not call pci_epf_alloc_space() before calling
pci_epc_set_bar(), so add a check in pci_epc_set_bar() to ensure that an
EPF driver cannot set a size different from the fixed BAR size, if the BAR
type is BAR_FIXED.

The pci_epc_function_is_valid() check is removed because this check is now
done by pci_epc_get_features().

Link: https://lore.kernel.org/r/20241213143301.4158431-13-cassel@kernel.org


Signed-off-by: default avatarNiklas Cassel <cassel@kernel.org>
Signed-off-by: default avatarKrzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: default avatarFrank Li <Frank.Li@nxp.com>
Reviewed-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
parent b61fef08

drivers/pci/endpoint/pci-epc-core.c

+9 −2
Original line number Diff line number Diff line
@@ -600,10 +600,17 @@ EXPORT_SYMBOL_GPL(pci_epc_clear_bar); 
int pci_epc_set_bar(struct pci_epc *epc, u8 func_no, u8 vfunc_no,

		    struct pci_epf_bar *epf_bar)

{

	int ret;

	const struct pci_epc_features *epc_features;

	enum pci_barno bar = epf_bar->barno;

	int flags = epf_bar->flags;

	int ret;



	if (!pci_epc_function_is_valid(epc, func_no, vfunc_no))

	epc_features = pci_epc_get_features(epc, func_no, vfunc_no);

	if (!epc_features)

		return -EINVAL;



	if (epc_features->bar[bar].type == BAR_FIXED &&

	    (epc_features->bar[bar].fixed_size != epf_bar->size))

		return -EINVAL;



	if ((epf_bar->barno == BAR_5 && flags & PCI_BASE_ADDRESS_MEM_TYPE_64) ||