From: Ma Wupeng <mawupeng1@huawei.com>
Check and return 0 if len == 0 at the beginning of the function.
Return -EINVAL if len overflows for mbind.
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
---
mm/mempolicy.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 85c5d3c2503b..7791be5a2677 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1275,13 +1275,16 @@ static long do_mbind(unsigned long start, unsigned long len,
if (mode == MPOL_DEFAULT)
flags &= ~MPOL_MF_STRICT;
+ if (!len)
+ return 0;
+
len = PAGE_ALIGN(len);
- end = start + len;
+ if (!len)
+ return -EINVAL;
+ end = start + len;
if (end < start)
return -EINVAL;
- if (end == start)
- return 0;
new = mpol_new(mode, mode_flags, nmask);
if (IS_ERR(new))
--
2.25.1