From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49779) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fYu6b-000449-2d for qemu-devel@nongnu.org; Fri, 29 Jun 2018 10:10:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fYu6Z-0004DU-HO for qemu-devel@nongnu.org; Fri, 29 Jun 2018 10:10:32 -0400 From: Kevin Wolf Date: Fri, 29 Jun 2018 16:09:50 +0200 Message-Id: <20180629140959.6690-21-kwolf@redhat.com> In-Reply-To: <20180629140959.6690-1-kwolf@redhat.com> References: <20180629140959.6690-1-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 20/29] iscsi: Don't blindly use designator length in response for memcpy 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: Fam Zheng Per SCSI definition the designator_length we receive from INQUIRY is 8, 12 or at most 16, but we should be careful because the remote iscsi target may misbehave, otherwise we could have a buffer overflow. Reported-by: Max Reitz Signed-off-by: Fam Zheng Signed-off-by: Kevin Wolf --- block/iscsi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/iscsi.c b/block/iscsi.c index bc84b14e20..9beb06d498 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -2226,7 +2226,7 @@ static void iscsi_populate_target_desc(unsigned char *desc, IscsiLun *lun) desc[5] = (dd->designator_type & 0xF) | ((dd->association & 3) << 4); desc[7] = dd->designator_length; - memcpy(desc + 8, dd->designator, dd->designator_length); + memcpy(desc + 8, dd->designator, MIN(dd->designator_length, 20)); desc[28] = 0; desc[29] = (lun->block_size >> 16) & 0xFF; -- 2.13.6