commit a2c0fe2fd26e3e10753660019da9366f7b19c286
author Peter Lieven <pl@kamp.de> Tue Jun 10 09:42:47 2014 +0200
committer Stefan Hajnoczi <stefanha@redhat.com> Mon Jun 16 17:23:19 2014 +0800
tree bff017734c531fe47ded4cc3a68bee632993a2d6
parent ae60e8e3783a66463d0736f3a48da9a66fd5cbd3

block/nfs: fix potential segfault on early callback

it will happen in the future that the callback of a libnfs call
directly invokes the callback. In this case we end up in a segfault
because the NFSRPC is gone when we the BH is scheduled.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

block/nfs.c

diff --git a/block/nfs.c b/block/nfs.c
index bd9177f..e282f8d 100644
--- a/block/nfs.c
+++ b/block/nfs.c
@@ -95,6 +95,7 @@
 static void nfs_co_generic_bh_cb(void *opaque)
 {
     NFSRPC *task = opaque;
+    task->complete = 1;
     qemu_bh_delete(task->bh);
     qemu_coroutine_enter(task->co, NULL);
 }
@@ -104,7 +105,6 @@
                   void *private_data)
 {
     NFSRPC *task = private_data;
-    task->complete = 1;
     task->ret = ret;
     if (task->ret > 0 && task->iov) {
         if (task->ret <= task->iov->size) {
@@ -123,6 +123,8 @@
         task->bh = aio_bh_new(task->client->aio_context,
                               nfs_co_generic_bh_cb, task);
         qemu_bh_schedule(task->bh);
+    } else {
+        task->complete = 1;
     }
 }