In al_pcie_config_prepare() resource_list_first_type() may return
NULL which is later dereferenced. Fix this bug by adding NULL check.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 0f71c60ffd26 ("PCI: dwc: Remove storing of PCI resources")
Signed-off-by: Aleksandr Mishin <amishin@xxxxxxxxxx>
---
v2: Add return code processing
drivers/pci/controller/dwc/pcie-al.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-al.c b/drivers/pci/controller/dwc/pcie-al.c
index 6dfdda59f328..933854c3575b 100644
--- a/drivers/pci/controller/dwc/pcie-al.c
+++ b/drivers/pci/controller/dwc/pcie-al.c
@@ -242,18 +242,24 @@ static struct pci_ops al_child_pci_ops = {
.write = pci_generic_config_write,
};
-static void al_pcie_config_prepare(struct al_pcie *pcie)
+static int al_pcie_config_prepare(struct al_pcie *pcie)
{
struct al_pcie_target_bus_cfg *target_bus_cfg;
struct dw_pcie_rp *pp = &pcie->pci->pp;
unsigned int ecam_bus_mask;
+ struct resource_entry *ft;
u32 cfg_control_offset;
+ struct resource *bus;
u8 subordinate_bus;
u8 secondary_bus;
u32 cfg_control;
u32 reg;
- struct resource *bus = resource_list_first_type(&pp->bridge->windows, IORESOURCE_BUS)->res;
+ ft = resource_list_first_type(&pp->bridge->windows, IORESOURCE_BUS);
+ if (!ft)
+ return -EINVAL;
+
+ bus = ft->res;
target_bus_cfg = &pcie->target_bus_cfg;
ecam_bus_mask = (pcie->ecam_size >> PCIE_ECAM_BUS_SHIFT) - 1;
@@ -287,6 +293,8 @@ static void al_pcie_config_prepare(struct al_pcie *pcie)
FIELD_PREP(CFG_CONTROL_SEC_BUS_MASK, secondary_bus);
al_pcie_controller_writel(pcie, cfg_control_offset, reg);
+
+ return 0;
}
static int al_pcie_host_init(struct dw_pcie_rp *pp)
@@ -305,7 +313,9 @@ static int al_pcie_host_init(struct dw_pcie_rp *pp)
if (rc)
return rc;
- al_pcie_config_prepare(pcie);
+ rc = al_pcie_config_prepare(pcie);
+ if (rc < 0)
+ return rc;
return 0;
}
--
2.30.2
