Commit 602414d1 authored Nov 05, 2018 by Liam Merwick Committed by Max Reitz Nov 12, 2018

block: Null pointer dereference in blk_root_get_parent_desc()



The dev_id returned by the call to blk_get_attached_dev_id() in
blk_root_get_parent_desc() can be NULL (an internal call to
object_get_canonical_path may have returned NULL).

Instead of just checking this case before before dereferencing,
adjust blk_get_attached_dev_id() to return the empty string if no
object path can be found (similar to the case when blk->dev is NULL
and an empty string is returned).

Signed-off-by: Liam Merwick <Liam.Merwick@oracle.com>
Message-id: 1541453919-25973-3-git-send-email-Liam.Merwick@oracle.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

parent c2032289

block/block-backend.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -918,7 +918,8 @@ char blk_get_attached_dev_id(BlockBackend blk)
		} else if (dev->id) {
		return g_strdup(dev->id);
		}
		return object_get_canonical_path(OBJECT(dev));

		return object_get_canonical_path(OBJECT(dev)) ?: g_strdup("");
		}

		/*