From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60021) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gMFfq-0000lP-Al for qemu-devel@nongnu.org; Mon, 12 Nov 2018 12:06:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gMFfp-0007JE-EP for qemu-devel@nongnu.org; Mon, 12 Nov 2018 12:06:54 -0500 From: Kevin Wolf Date: Mon, 12 Nov 2018 18:06:00 +0100 Message-Id: <20181112170603.23986-12-kwolf@redhat.com> In-Reply-To: <20181112170603.23986-1-kwolf@redhat.com> References: <20181112170603.23986-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL 11/14] block: Null pointer dereference in blk_root_get_parent_desc() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: kwolf@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org From: Liam Merwick 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 Message-id: 1541453919-25973-3-git-send-email-Liam.Merwick@oracle.com Reviewed-by: Max Reitz Signed-off-by: Max Reitz --- 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 2a8f3b55f8..60d37a0c3d 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(""); } =20 /* --=20 2.19.1