From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50678) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XFoAR-0005Mh-2m for qemu-devel@nongnu.org; Fri, 08 Aug 2014 13:41:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XFoAL-0007BV-5D for qemu-devel@nongnu.org; Fri, 08 Aug 2014 13:41:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:7750) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XFoAK-0007BJ-SD for qemu-devel@nongnu.org; Fri, 08 Aug 2014 13:41:21 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s78HfKZr010716 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Fri, 8 Aug 2014 13:41:20 -0400 From: Kevin Wolf Date: Fri, 8 Aug 2014 19:39:56 +0200 Message-Id: <1407519603-6635-56-git-send-email-kwolf@redhat.com> In-Reply-To: <1407519603-6635-1-git-send-email-kwolf@redhat.com> References: <1407519603-6635-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 55/62] vhdx: Handle failure for potentially large allocations List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com Some code in the block layer makes potentially huge allocations. Failure is not completely unexpected there, so avoid aborting qemu and handle out-of-memory situations gracefully. This patch addresses the allocations in the vhdx block driver. Signed-off-by: Kevin Wolf Reviewed-by: Stefan Hajnoczi Reviewed-by: Benoit Canet --- block/vhdx-log.c | 7 ++++++- block/vhdx.c | 13 +++++++++++-- 2 files changed, 17 insertions(+), 3 deletions(-) diff --git a/block/vhdx-log.c b/block/vhdx-log.c index 0088be8..eb5c7a0 100644 --- a/block/vhdx-log.c +++ b/block/vhdx-log.c @@ -352,7 +352,12 @@ static int vhdx_log_read_desc(BlockDriverState *bs, BDRVVHDXState *s, } desc_sectors = vhdx_compute_desc_sectors(hdr.descriptor_count); - desc_entries = qemu_blockalign(bs, desc_sectors * VHDX_LOG_SECTOR_SIZE); + desc_entries = qemu_try_blockalign(bs->file, + desc_sectors * VHDX_LOG_SECTOR_SIZE); + if (desc_entries == NULL) { + ret = -ENOMEM; + goto exit; + } ret = vhdx_log_read_sectors(bs, log, §ors_read, desc_entries, desc_sectors, false); diff --git a/block/vhdx.c b/block/vhdx.c index febce21..f666940 100644 --- a/block/vhdx.c +++ b/block/vhdx.c @@ -958,7 +958,12 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, } /* s->bat is freed in vhdx_close() */ - s->bat = qemu_blockalign(bs, s->bat_rt.length); + s->bat = qemu_try_blockalign(bs->file, s->bat_rt.length); + if (s->bat == NULL) { + ret = -ENOMEM; + goto fail; + } + ret = bdrv_pread(bs->file, s->bat_offset, s->bat, s->bat_rt.length); if (ret < 0) { goto fail; @@ -1587,7 +1592,11 @@ static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, use_zero_blocks || bdrv_has_zero_init(bs) == 0) { /* for a fixed file, the default BAT entry is not zero */ - s->bat = g_malloc0(length); + s->bat = g_try_malloc0(length); + if (length && s->bat != NULL) { + ret = -ENOMEM; + goto exit; + } block_state = type == VHDX_TYPE_FIXED ? PAYLOAD_BLOCK_FULLY_PRESENT : PAYLOAD_BLOCK_NOT_PRESENT; block_state = use_zero_blocks ? PAYLOAD_BLOCK_ZERO : block_state; -- 1.8.3.1