From: Ma Wupeng <mawupeng1@xxxxxxxxxx>
Return -EINVAL if len overflows for set_mempolicy_home_node.
Signed-off-by: Ma Wupeng <mawupeng1@xxxxxxxxxx>
---
mm/mempolicy.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index a256a241fd1d..3a68998adc3a 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1489,6 +1489,7 @@ SYSCALL_DEFINE4(set_mempolicy_home_node, unsigned long, start, unsigned long, le
unsigned long, home_node, unsigned long, flags)
{
struct mm_struct *mm = current->mm;
+ unsigned long old_len = len;
struct vm_area_struct *vma;
struct mempolicy *new, *old;
unsigned long vmstart;
@@ -1516,7 +1517,7 @@ SYSCALL_DEFINE4(set_mempolicy_home_node, unsigned long, start, unsigned long, le
len = PAGE_ALIGN(len);
end = start + len;
- if (end < start)
+ if (end < start || (old_len != 0 && len == 0))
return -EINVAL;
if (end == start)
return 0;
--
2.25.1
