From 1b0b2e6d06c26185ecc820e868e025c894f979f7 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Wed, 31 Mar 2021 15:27:27 +0100 Subject: [PATCH] block/export: improve vu_blk_sect_range_ok() The checks in vu_blk_sect_range_ok() assume VIRTIO_BLK_SECTOR_SIZE is equal to BDRV_SECTOR_SIZE. This is true, but let's add a QEMU_BUILD_BUG_ON() to make it explicit. We might as well check that the request buffer size is a multiple of VIRTIO_BLK_SECTOR_SIZE while we're at it. Suggested-by: Max Reitz Signed-off-by: Stefan Hajnoczi Message-Id: <20210331142727.391465-1-stefanha@redhat.com> Reviewed-by: Eric Blake Signed-off-by: Kevin Wolf --- block/export/vhost-user-blk-server.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c index fa06996d37..1862563336 100644 --- a/block/export/vhost-user-blk-server.c +++ b/block/export/vhost-user-blk-server.c @@ -70,9 +70,16 @@ static void vu_blk_req_complete(VuBlkReq *req) static bool vu_blk_sect_range_ok(VuBlkExport *vexp, uint64_t sector, size_t size) { - uint64_t nb_sectors = size >> BDRV_SECTOR_BITS; + uint64_t nb_sectors; uint64_t total_sectors; + if (size % VIRTIO_BLK_SECTOR_SIZE) { + return false; + } + + nb_sectors = size >> VIRTIO_BLK_SECTOR_BITS; + + QEMU_BUILD_BUG_ON(BDRV_SECTOR_SIZE != VIRTIO_BLK_SECTOR_SIZE); if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) { return false; }