bus: fsl-mc: Check return value of platform_get_resource()

commit 25f526507b8ccc6ac3a43bc094d09b1f9b0b90ae upstream.

platform_get_resource() returns NULL in case of failure, so check its
return value and propagate the error in order to prevent NULL pointer
dereference.

Fixes: 6305166 ("bus: fsl-mc: Add ACPI support for fsl-mc")
Cc: [email protected]
Signed-off-by: Salah Triki <[email protected]>
Acked-by: Ioana Ciornei <[email protected]>
Link: https://lore.kernel.org/r/aKwuK6TRr5XNYQ8u@pc
Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: salah-triki

drivers/bus/fsl-mc/fsl-mc-bus.c

@@ -1104,6 +1104,9 @@ static int fsl_mc_bus_probe(struct platform_device *pdev)
 	 * Get physical address of MC portal for the root DPRC:
 	 */
 	plat_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!plat_res)
+		return -EINVAL;
+
 	mc_portal_phys_addr = plat_res->start;
 	mc_portal_size = resource_size(plat_res);
 	mc_portal_base_phys_addr = mc_portal_phys_addr & ~0x3ffffff;