From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36222) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gJmaP-0007IB-M5 for qemu-devel@nongnu.org; Mon, 05 Nov 2018 16:39:06 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gJmaK-0003FZ-W5 for qemu-devel@nongnu.org; Mon, 05 Nov 2018 16:39:04 -0500 From: Liam Merwick Date: Mon, 5 Nov 2018 21:38:36 +0000 Message-Id: <1541453919-25973-3-git-send-email-Liam.Merwick@oracle.com> In-Reply-To: <1541453919-25973-1-git-send-email-Liam.Merwick@oracle.com> References: <1541453919-25973-1-git-send-email-Liam.Merwick@oracle.com> Subject: [Qemu-devel] [PATCH v5 2/5] block: Null pointer dereference in blk_root_get_parent_desc() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, kwolf@redhat.com, jsnow@redhat.com, berrange@redhat.com, mreitz@redhat.com 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 --- block/block-backend.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/block/block-backend.c b/block/block-backend.c index dc0cd5772413..a2061a565024 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -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(""); } /* -- 1.8.3.1