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(). Signed-off-by: Niklas Cassel <cassel@xxxxxxxxxx> --- drivers/pci/endpoint/pci-epc-core.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index bed7c7d1fe3c3..c69c133701c92 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -609,10 +609,17 @@ 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) || -- 2.47.0