From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34357) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dezur-0003wO-C1 for qemu-devel@nongnu.org; Tue, 08 Aug 2017 04:31:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dezuq-000189-6b for qemu-devel@nongnu.org; Tue, 08 Aug 2017 04:31:05 -0400 Date: Tue, 8 Aug 2017 10:30:54 +0200 From: Kevin Wolf Message-ID: <20170808083054.GC4850@dhcp-200-186.str.redhat.com> References: <20170807203007.19033-1-eblake@redhat.com> <20170807203007.19033-2-eblake@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170807203007.19033-2-eblake@redhat.com> Subject: Re: [Qemu-devel] [PATCH 1/4] vpc: Check failure of bdrv_getlength() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake Cc: qemu-devel@nongnu.org, armbru@redhat.com, qemu-block@nongnu.org, Max Reitz Am 07.08.2017 um 22:30 hat Eric Blake geschrieben: > vpc_open() was checking for bdrv_getlength() failure in one, but > not the other, location. > > Reported-by: Markus Armbruster > Signed-off-by: Eric Blake > --- > block/vpc.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/block/vpc.c b/block/vpc.c > index 574879ba7c..468d10ec1c 100644 > --- a/block/vpc.c > +++ b/block/vpc.c > @@ -219,6 +219,7 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags, > uint64_t pagetable_size; > int disk_type = VHD_DYNAMIC; > int ret; > + int64_t bs_size; > > bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, > false, errp); > @@ -411,7 +412,13 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags, > } > } > > - if (s->free_data_block_offset > bdrv_getlength(bs->file->bs)) { > + bs_size = bdrv_getlength(bs->file->bs); > + if (bs_size < 0) { > + error_setg_errno(errp, -bs_size, "unable to learn image size"); I would start the error message with a capital letter for consistency with other messages in this function. (It has obviously nothing to do with my general preference for that style.) > + ret = bs_size; > + goto fail; > + } > + if (s->free_data_block_offset > bs_size) { > error_setg(errp, "block-vpc: free_data_block_offset points after " > "the end of file. The image has been truncated."); > ret = -EINVAL; Kevin