In some case the cma area could not be activated, but the cma_alloc be
used under this case, then the kernel will crash caused by NULL pointer
dereference.
Add bitmap valid check in cma_alloc to avoid this issue.
Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: http://lkml.kernel.org/r/20200615010123.15596-1-jay.xu@rock-chips.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
struct page *page = NULL;
int ret = -ENOMEM;
- if (!cma || !cma->count)
+ if (!cma || !cma->count || !cma->bitmap)
return NULL;
pr_debug("%s(cma %p, count %zu, align %d)\n", __func__, (void *)cma,