From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45905) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1deofd-0007KO-0x for qemu-devel@nongnu.org; Mon, 07 Aug 2017 16:30:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1deofY-00049w-8D for qemu-devel@nongnu.org; Mon, 07 Aug 2017 16:30:37 -0400 From: Eric Blake Date: Mon, 7 Aug 2017 15:30:07 -0500 Message-Id: <20170807203007.19033-5-eblake@redhat.com> In-Reply-To: <20170807203007.19033-1-eblake@redhat.com> References: <20170807203007.19033-1-eblake@redhat.com> Subject: [Qemu-devel] [PATCH 4/4] qcow2: Check failure of bdrv_getlength() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, armbru@redhat.com, qemu-block@nongnu.org, Max Reitz qcow2_co_pwritev_compressed() should not call bdrv_truncate() if determining the size failed. Reported-by: Markus Armbruster Signed-off-by: Eric Blake --- block/qcow2.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/block/qcow2.c b/block/qcow2.c index 99407403ea..40ba26c111 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3282,12 +3282,15 @@ qcow2_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset, z_stream strm; int ret, out_len; uint8_t *buf, *out_buf; - uint64_t cluster_offset; + int64_t cluster_offset; if (bytes == 0) { /* align end of file to a sector boundary to ease reading with sector based I/Os */ cluster_offset = bdrv_getlength(bs->file->bs); + if (cluster_offset < 0) { + return cluster_offset; + } return bdrv_truncate(bs->file, cluster_offset, PREALLOC_MODE_OFF, NULL); } -- 2.13.4