Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Pull request

# gpg: Signature made Thu 22 Aug 2019 16:52:45 BST
# gpg:                using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
  vhost-user-scsi: prevent using uninitialized vqs
  util/async: hold AioContext ref to prevent use-after-free

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
index 31c9d34637b6f33128ded17f689769f4d7dd4d0a..6a6c15dd32f07e0c38b03b45ec96047bf8d0ad6f 100644 (file)
--- a/hw/scsi/vhost-user-scsi.c
+++ b/hw/scsi/vhost-user-scsi.c
@@ -93,7 +93,7 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
     }
 
     vsc->dev.nvqs = 2 + vs->conf.num_queues;
-    vsc->dev.vqs = g_new(struct vhost_virtqueue, vsc->dev.nvqs);
+    vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs);
     vsc->dev.vq_index = 0;
     vsc->dev.backend_features = 0;
     vqs = vsc->dev.vqs;

diff --git a/util/async.c b/util/async.c
index 8d2105729c147a54d17bd3dcce65d82d80ada049..4e4c7af51e0e776bffdf4156d244c6b114fe3c8f 100644 (file)
--- a/util/async.c
+++ b/util/async.c
@@ -459,9 +459,17 @@ void aio_co_schedule(AioContext *ctx, Coroutine *co)
         abort();
     }
 
+    /* The coroutine might run and release the last ctx reference before we
+     * invoke qemu_bh_schedule().  Take a reference to keep ctx alive until
+     * we're done.
+     */
+    aio_context_ref(ctx);
+
     QSLIST_INSERT_HEAD_ATOMIC(&ctx->scheduled_coroutines,
                               co, co_scheduled_next);
     qemu_bh_schedule(ctx->co_schedule_bh);
+
+    aio_context_unref(ctx);
 }
 
 void aio_co_wake(struct Coroutine *co)