block: Fix multiwrite error handling

When two requests of the same multiwrite batch fail, the callback of all requests in that batch were called twice. This could have any kind of nasty effects, in my case it lead to use after free and eventually a segfault.

Signed-off-by Kevin Wolf <[email protected]>

---
 block.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

block.c +1 -1

index 31610af..1c36e91 100644
@@ -1734,7 +1734,7 @@ static void multiwrite_cb(void *opaque, int ret)
 {
     MultiwriteCB *mcb = opaque;
 
-    if (ret < 0) {
+    if (ret < 0 && !mcb->error) {
         mcb->error = ret;
         multiwrite_user_cb(mcb);
     }

Signature · 1 line

1.6.6.1