From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35856) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dcBps-0000WR-Ok for qemu-devel@nongnu.org; Mon, 31 Jul 2017 10:38:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dcBpo-0001yy-QV for qemu-devel@nongnu.org; Mon, 31 Jul 2017 10:38:20 -0400 Date: Mon, 31 Jul 2017 10:38:09 -0400 From: Jeff Cody Message-ID: <20170731143809.GC22129@localhost.localdomain> References: <20170731125111.28052-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170731125111.28052-1-kwolf@redhat.com> Subject: Re: [Qemu-devel] [PATCH for-2.10] block/qapi: Remove redundat NULL check to silence Coverity List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: qemu-block@nongnu.org, peter.maydell@linaro.org, qemu-devel@nongnu.org On Mon, Jul 31, 2017 at 02:51:11PM +0200, Kevin Wolf wrote: > When skipping implicit nodes in bdrv_block_device_info(), we know that > bs0 is always non-NULL; initially, because it's taken from a BdrvChild Not to mention, we deference bs0 in the chunk of code right above this, so we'd segfault anyway if the initial value was NULL. > and a BdrvChild never has a NULL bs, and after the first iteration > because implicit nodes always have a backing file. > > Remove the NULL check and add an assertion that the implicit node does > indeed have a backing file. > > Signed-off-by: Kevin Wolf Reviewed-by: Jeff Cody > --- > block/qapi.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/block/qapi.c b/block/qapi.c > index d2b18ee9df..5f1a71f5d2 100644 > --- a/block/qapi.c > +++ b/block/qapi.c > @@ -145,8 +145,9 @@ BlockDeviceInfo *bdrv_block_device_info(BlockBackend *blk, > > /* Skip automatically inserted nodes that the user isn't aware of for > * query-block (blk != NULL), but not for query-named-block-nodes */ > - while (blk && bs0 && bs0->drv && bs0->implicit) { > + while (blk && bs0->drv && bs0->implicit) { > bs0 = backing_bs(bs0); > + assert(bs0); > } > } > > -- > 2.13.3 > >