From b5d7bebd96a3d002bb14a96af88802c876ef0790 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Tue, 29 Jun 2021 12:40:24 +0200
Subject: [PATCH] nds32: fix up stack guard gap

commit c453db6cd96418c79702eaf38259002755ab23ff upstream.

Commit 1be7107fbe18 ("mm: larger stack guard gap, between vmas") fixed
up all architectures to deal with the stack guard gap.  But when nds32
was added to the tree, it forgot to do the same thing.

Resolve this by properly fixing up the nsd32's version of
arch_get_unmapped_area()

Cc: Nick Hu <nickhu@andestech.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Qiang Liu <cyruscyliu@gmail.com>
Cc: stable <stable@vger.kernel.org>
Reported-by: iLifetruth <yixiaonn@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Link: https://lore.kernel.org/r/20210629104024.2293615-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/nds32/mm/mmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/nds32/mm/mmap.c b/arch/nds32/mm/mmap.c
index c206b31ce07a..1bdf5e7d1b43 100644
--- a/arch/nds32/mm/mmap.c
+++ b/arch/nds32/mm/mmap.c
@@ -59,7 +59,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 
 		vma = find_vma(mm, addr);
 		if (TASK_SIZE - len >= addr &&
-		    (!vma || addr + len <= vma->vm_start))
+		    (!vma || addr + len <= vm_start_gap(vma)))
 			return addr;
 	}