[PATCH] mm: fadvise: avoid signed integer overflow calculating offset

[Sasha Levin <sasha.levin@oracle.com>]

Both offset and len are signed integers who's overflow isn't defined. Use
unsigned addition to avoid the issue.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
---
 mm/fadvise.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/fadvise.c b/mm/fadvise.c
index 3bcfd81d..762cb63 100644
--- a/mm/fadvise.c
+++ b/mm/fadvise.c
@@ -67,7 +67,7 @@ SYSCALL_DEFINE4(fadvise64_64, int, fd, loff_t, offset, loff_t, len, int, advice)
 	}
 
 	/* Careful about overflows. Len == 0 means "as much as possible" */
-	endbyte = offset + len;
+	endbyte = offset + (u64)len;
 	if (!len || endbyte < len)
 		endbyte = -1;
 	else
-- 
1.7.10.4