[Qemu-devel] [PATCH] mirror: correct buf_size

[Wen Congyang]

If buf_size % granularity is not 0, mirror_free_init() will
do dangerous things.

Signed-off-by: Wen Congyang <address@hidden>
---
 block/mirror.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/block/mirror.c b/block/mirror.c
index 58f391a..bb6bc27 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -686,6 +686,10 @@ static void mirror_start_job(BlockDriverState *bs, 
BlockDriverState *target,
     s->granularity = granularity;
     s->buf_size = MAX(buf_size, granularity);
 
+    if (s->buf_size % granularity != 0) {
+        s->buf_size = ROUND_UP(s->buf_size, granularity);
+    }
+
     s->dirty_bitmap = bdrv_create_dirty_bitmap(bs, granularity, NULL, errp);
     if (!s->dirty_bitmap) {
         return;
-- 
2.1.0