[PATCH] mm/msync: exit early when the flags is an MS_ASYNC and start < vm_start

[Nikita Ermakov <sh1r4s3@xxxxxxxxxxxxxxx>]

Exit from the loop over the VMA in the case when the flags
contain only an MS_ASYNC and start < vm_start. In this case msync()
would return with -ENOMEM anyway so make it return early.

Signed-off-by: Nikita Ermakov <sh1r4s3@xxxxxxxxxxxxxxx>
---
 mm/msync.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/msync.c b/mm/msync.c
index 69c6d2029531..ed20c3621d4c 100644
--- a/mm/msync.c
+++ b/mm/msync.c
@@ -69,6 +69,8 @@ SYSCALL_DEFINE3(msync, unsigned long, start, size_t, len, int, flags)
 			goto out_unlock;
 		/* Here start < vma->vm_end. */
 		if (start < vma->vm_start) {
+			if (flags == MS_ASYNC)
+				goto out_unlock;
 			start = vma->vm_start;
 			if (start >= end)
 				goto out_unlock;

base-commit: 6824a8a9b4861d7df7ee132a952bdf6f84a99cb8
-- 
2.28.0