Blackfin arch: have is_user_addr_valid() check for overflows (like when address is -1)
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c
index 7e1f762..140bf00 100644
--- a/arch/blackfin/kernel/ptrace.c
+++ b/arch/blackfin/kernel/ptrace.c
@@ -160,6 +160,10 @@
struct vm_list_struct *vml;
struct sram_list_struct *sraml;
+ /* overflow */
+ if (start + len < start)
+ return -EIO;
+
for (vml = child->mm->context.vmlist; vml; vml = vml->next)
if (start >= vml->vma->vm_start && start + len < vml->vma->vm_end)
return 0;