[PATCH] mm/mremap: fix uninitialized return code

[Arnd Bergmann]

From: Arnd Bergmann <arnd@xxxxxxxx>

The 'err' variable is set in a conditinal branch and is not
set otherwise:

mm/mremap.c:1017:7: error: variable 'err' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
 1017 |                 if (vma->vm_start != old_addr)

Set it to zero before the initial value is set.

Fixes: 3129f7896afb ("mm/mremap: initial refactor of move_vma()")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 mm/mremap.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/mremap.c b/mm/mremap.c
index 456849b9e7bd..9c51a2360d84 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -1014,6 +1014,7 @@ static unsigned long prep_move_vma(struct vma_remap_struct *vrm)
 		return -ENOMEM;
 
 	if (vma->vm_ops && vma->vm_ops->may_split) {
+		err = 0;
 		if (vma->vm_start != old_addr)
 			err = vma->vm_ops->may_split(vma, old_addr);
 		if (!err && vma->vm_end != old_addr + old_len)
-- 
2.39.5