From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34483) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eyuqw-0004d6-CO for qemu-devel@nongnu.org; Thu, 22 Mar 2018 03:41:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eyuqr-0005gO-8k for qemu-devel@nongnu.org; Thu, 22 Mar 2018 03:41:38 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:58110 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eyuqr-0005gC-3m for qemu-devel@nongnu.org; Thu, 22 Mar 2018 03:41:33 -0400 Date: Thu, 22 Mar 2018 15:41:29 +0800 From: Fam Zheng Message-ID: <20180322074129.GF26618@lemon.usersys.redhat.com> References: <20180322062447.16537-1-yuchenlin@synology.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180322062447.16537-1-yuchenlin@synology.com> Subject: Re: [Qemu-devel] [PATCH v2] vmdk: return ERROR when cluster sector is larger than vmdk limitation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: yuchenlin@synology.com Cc: qemu-devel@nongnu.org, kwolf@redhat.com, mreitz@redhat.com On Thu, 03/22 14:24, yuchenlin@synology.com wrote: > From: yuchenlin > > VMDK has a hard limitation of extent size, which is due to the size of grain > table entry is 32 bits. It means it can only point to a grain located at > offset = 2^32. To avoid writing the user data beyond limitation and record a useless offset > in grain table. We should return ERROR here. > > Signed-off-by: yuchenlin > --- > v1->v2: > - change commit message > - check before allocating > - should be >= > - the unit is sector now > > thanks > > block/vmdk.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/block/vmdk.c b/block/vmdk.c > index f94c49a9c0..a1c21dbbba 100644 > --- a/block/vmdk.c > +++ b/block/vmdk.c > @@ -47,6 +47,8 @@ > #define VMDK4_FLAG_MARKER (1 << 17) > #define VMDK4_GD_AT_END 0xffffffffffffffffULL > > +#define VMDK_EXTENT_MAX_SECTORS (4294967296) > + > #define VMDK_GTE_ZEROED 0x1 > > /* VMDK internal error codes */ > @@ -1250,6 +1252,10 @@ static int get_cluster_offset(BlockDriverState *bs, > return zeroed ? VMDK_ZEROED : VMDK_UNALLOC; > } > > + if (extent->next_cluster_sector >= VMDK_EXTENT_MAX_SECTORS) { > + return VMDK_ERROR; > + } > + > cluster_sector = extent->next_cluster_sector; > extent->next_cluster_sector += extent->cluster_sectors; > > -- > 2.16.2 > Cc'ing Kevin and Max who merge block/ patches. Reviewed-by: Fam Zheng