From fb43d2d46e0daa491d7d80683dd11bb7b2f5899e Mon Sep 17 00:00:00 2001 From: Alberto Garcia Date: Mon, 6 Apr 2020 16:34:01 +0200 Subject: [PATCH] qcow2: Check request size in qcow2_co_pwritev_compressed_part() When issuing a compressed write request the number of bytes must be a multiple of the cluster size or reach the end of the last cluster. With the current code such requests are allowed and we hit an assertion: $ qemu-img create -f qcow2 img.qcow2 1M $ qemu-io -c 'write -c 0 32k' img.qcow2 qemu-io: block/qcow2.c:4257: qcow2_co_pwritev_compressed_task: Assertion `bytes == s->cluster_size || (bytes < s->cluster_size && (offset + bytes == bs->total_sectors << BDRV_SECTOR_BITS))' failed. Aborted This patch fixes a regression introduced in 0d483dce38 Signed-off-by: Alberto Garcia Message-Id: <20200406143401.26854-1-berto@igalia.com> Reviewed-by: Andrey Shinkevich Reviewed-by: Vladimir Sementsov-Ogievskiy Signed-off-by: Max Reitz --- block/qcow2.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/block/qcow2.c b/block/qcow2.c index e8cbcc1ec1..b524b0c53f 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -4355,6 +4355,11 @@ qcow2_co_pwritev_compressed_part(BlockDriverState *bs, return -EINVAL; } + if (offset_into_cluster(s, bytes) && + (offset + bytes) != (bs->total_sectors << BDRV_SECTOR_BITS)) { + return -EINVAL; + } + while (bytes && aio_task_pool_status(aio) == 0) { uint64_t chunk_size = MIN(bytes, s->cluster_size);