of: Fix NULL dereference in unflatten_and_copy()

Check whether initial_boot_params is NULL before dereferencing it in
unflatten_and_copy_device_tree() for the case where no device tree is
available but the arch can still boot to a minimal usable system without
it. In this case also log a warning for when the kernel log buffer is
obtainable.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
This commit is contained in:
James Hogan 2013-11-21 13:44:14 +00:00 committed by Grant Likely
parent 374b105797
commit 6f041e99fc

View file

@ -922,8 +922,16 @@ void __init unflatten_device_tree(void)
*/
void __init unflatten_and_copy_device_tree(void)
{
int size = __be32_to_cpu(initial_boot_params->totalsize);
void *dt = early_init_dt_alloc_memory_arch(size,
int size;
void *dt;
if (!initial_boot_params) {
pr_warn("No valid device tree found, continuing without\n");
return;
}
size = __be32_to_cpu(initial_boot_params->totalsize);
dt = early_init_dt_alloc_memory_arch(size,
__alignof__(struct boot_param_header));
if (dt) {