Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2020-02-26' into staging

nbd patches for 2020-02-26

- ensure multiple meta contexts work
- allow leading / in export names
- fix a failure path memory leak

# gpg: Signature made Thu 27 Feb 2020 01:53:03 GMT
# gpg:                using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full]
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full]
# gpg:                 aka "[jpeg image of size 6874]" [full]
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2020-02-26:
  block/nbd: fix memory leak in nbd_open()
  block/nbd: extract the common cleanup code
  nbd-client: Support leading / in NBD URI
  nbd: Fix regression with multiple meta contexts

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

2 files changed, 30 insertions, 15 deletions

diff --git a/block/nbd.c b/block/nbd.c
index 6d3b22f844..976be76647 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -95,6 +95,19 @@ typedef struct BDRVNBDState {
 
 static int nbd_client_connect(BlockDriverState *bs, Error **errp);
 
+static void nbd_clear_bdrvstate(BDRVNBDState *s)
+{
+    object_unref(OBJECT(s->tlscreds));
+    qapi_free_SocketAddress(s->saddr);
+    s->saddr = NULL;
+    g_free(s->export);
+    s->export = NULL;
+    g_free(s->tlscredsid);
+    s->tlscredsid = NULL;
+    g_free(s->x_dirty_bitmap);
+    s->x_dirty_bitmap = NULL;
+}
+
 static void nbd_channel_error(BDRVNBDState *s, int ret)
 {
     if (ret == -EIO) {
@@ -1528,8 +1541,10 @@ static int nbd_parse_uri(const char *filename, QDict *options)
         goto out;
     }
 
-    p = uri->path ? uri->path : "/";
-    p += strspn(p, "/");
+    p = uri->path ? uri->path : "";
+    if (p[0] == '/') {
+        p++;
+    }
     if (p[0]) {
         qdict_put_str(options, "export", p);
     }
@@ -1877,11 +1892,7 @@ static int nbd_process_options(BlockDriverState *bs, QDict *options,
 
  error:
     if (ret < 0) {
-        object_unref(OBJECT(s->tlscreds));
-        qapi_free_SocketAddress(s->saddr);
-        g_free(s->export);
-        g_free(s->tlscredsid);
-        g_free(s->x_dirty_bitmap);
+        nbd_clear_bdrvstate(s);
     }
     qemu_opts_del(opts);
     return ret;
@@ -1904,6 +1915,7 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
 
     ret = nbd_client_connect(bs, errp);
     if (ret < 0) {
+        nbd_clear_bdrvstate(s);
         return ret;
     }
     /* successfully connected */
@@ -1960,12 +1972,7 @@ static void nbd_close(BlockDriverState *bs)
     BDRVNBDState *s = bs->opaque;
 
     nbd_client_close(bs);
-
-    object_unref(OBJECT(s->tlscreds));
-    qapi_free_SocketAddress(s->saddr);
-    g_free(s->export);
-    g_free(s->tlscredsid);
-    g_free(s->x_dirty_bitmap);
+    nbd_clear_bdrvstate(s);
 }
 
 static int64_t nbd_getlength(BlockDriverState *bs)
diff --git a/nbd/server.c b/nbd/server.c
index 87fcd2e7bf..11a31094ff 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -2384,15 +2384,23 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
                                                !client->export_meta.bitmap,
                                                NBD_META_ID_BASE_ALLOCATION,
                                                errp);
-            } else {              /* client->export_meta.bitmap */
+                if (ret < 0) {
+                    return ret;
+                }
+            }
+
+            if (client->export_meta.bitmap) {
                 ret = nbd_co_send_bitmap(client, request->handle,
                                          client->exp->export_bitmap,
                                          request->from, request->len,
                                          dont_fragment,
                                          true, NBD_META_ID_DIRTY_BITMAP, errp);
+                if (ret < 0) {
+                    return ret;
+                }
             }
 
-            return ret;
+            return 0;
         } else {
             return nbd_send_generic_reply(client, request->handle, -EINVAL,
                                           "CMD_BLOCK_STATUS not negotiated",