From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34192) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bg4Wf-0001gb-Uh for qemu-devel@nongnu.org; Sat, 03 Sep 2016 02:34:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bg4Wc-0007OK-O8 for qemu-devel@nongnu.org; Sat, 03 Sep 2016 02:34:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38608) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bg4Wc-0007NA-IV for qemu-devel@nongnu.org; Sat, 03 Sep 2016 02:33:58 -0400 From: P J P Date: Sat, 3 Sep 2016 12:03:48 +0530 Message-Id: <1472884428-9975-1-git-send-email-ppandit@redhat.com> Subject: [Qemu-devel] [PATCH] scsi: pvscsi: request descriptor data_length to 32 bit List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Qemu Developers Cc: Dmitry Fleytman , Paolo Bonzini , Li Qiang , Prasad J Pandit From: Prasad J Pandit In PVSCSI paravirtual SCSI bus, the request descriptor data length is defined to be 64 bit. While building SG list from a request descriptor, it gets truncated to 32bit in routine 'pvscsi_convert_sglist'. This could lead to an infinite loop situation for arbitrarily large 'dataLen' values. Define local variable 'data_length' to be 32 bit, to avoid it. Reported-by: Li Qiang Signed-off-by: Prasad J Pandit --- hw/scsi/vmw_pvscsi.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c index 4245c15..4d38330 100644 --- a/hw/scsi/vmw_pvscsi.c +++ b/hw/scsi/vmw_pvscsi.c @@ -629,7 +629,7 @@ static void pvscsi_convert_sglist(PVSCSIRequest *r) { int chunk_size; - uint64_t data_length = r->req.dataLen; + uint32_t data_length = r->req.dataLen; PVSCSISGState sg = r->sg; while (data_length) { while (!sg.resid) { @@ -637,8 +637,7 @@ pvscsi_convert_sglist(PVSCSIRequest *r) trace_pvscsi_convert_sglist(r->req.context, r->sg.dataAddr, r->sg.resid); } - assert(data_length > 0); - chunk_size = MIN((unsigned) data_length, sg.resid); + chunk_size = MIN(data_length, sg.resid); if (chunk_size) { qemu_sglist_add(&r->sgl, sg.dataAddr, chunk_size); } -- 2.5.5