From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59601) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WsXqr-0000sy-Ns for qemu-devel@nongnu.org; Thu, 05 Jun 2014 09:37:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WsXqk-00045J-4N for qemu-devel@nongnu.org; Thu, 05 Jun 2014 09:37:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:26806) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WsXqj-00045B-SY for qemu-devel@nongnu.org; Thu, 05 Jun 2014 09:36:58 -0400 From: Kevin Wolf Date: Thu, 5 Jun 2014 15:36:22 +0200 Message-Id: <1401975393-7255-11-git-send-email-kwolf@redhat.com> In-Reply-To: <1401975393-7255-1-git-send-email-kwolf@redhat.com> References: <1401975393-7255-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PATCH v4 10/21] qcow1: 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, benoit.canet@irqsave.net, stefanha@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 qcow1 block driver. Signed-off-by: Kevin Wolf Reviewed-by: Stefan Hajnoczi --- block/qcow.c | 33 ++++++++++++++++++++++++++------- 1 file changed, 26 insertions(+), 7 deletions(-) diff --git a/block/qcow.c b/block/qcow.c index 7fd57d7..31db585 100644 --- a/block/qcow.c +++ b/block/qcow.c @@ -182,7 +182,12 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, } s->l1_table_offset = header.l1_table_offset; - s->l1_table = g_malloc(s->l1_size * sizeof(uint64_t)); + s->l1_table = g_try_malloc(s->l1_size * sizeof(uint64_t)); + if (s->l1_table == NULL) { + error_setg(errp, "Could not allocate memory for L1 table"); + ret = -ENOMEM; + goto fail; + } ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)); @@ -193,8 +198,16 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, for(i = 0;i < s->l1_size; i++) { be64_to_cpus(&s->l1_table[i]); } - /* alloc L2 cache */ - s->l2_cache = g_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); + + /* alloc L2 cache (max. 64k * 16 * 8 = 8 MB) */ + s->l2_cache = + qemu_try_blockalign(bs->file, + s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); + if (s->l2_cache == NULL) { + error_setg(errp, "Could not allocate L2 table cache"); + ret = -ENOMEM; + goto fail; + } s->cluster_cache = g_malloc(s->cluster_size); s->cluster_data = g_malloc(s->cluster_size); s->cluster_cache_offset = -1; @@ -226,7 +239,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, fail: g_free(s->l1_table); - g_free(s->l2_cache); + qemu_vfree(s->l2_cache); g_free(s->cluster_cache); g_free(s->cluster_data); return ret; @@ -517,7 +530,10 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num, void *orig_buf; if (qiov->niov > 1) { - buf = orig_buf = qemu_blockalign(bs, qiov->size); + buf = orig_buf = qemu_try_blockalign(bs, qiov->size); + if (buf == NULL) { + return -ENOMEM; + } } else { orig_buf = NULL; buf = (uint8_t *)qiov->iov->iov_base; @@ -619,7 +635,10 @@ static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num, s->cluster_cache_offset = -1; /* disable compressed cache */ if (qiov->niov > 1) { - buf = orig_buf = qemu_blockalign(bs, qiov->size); + buf = orig_buf = qemu_try_blockalign(bs, qiov->size); + if (buf == NULL) { + return -ENOMEM; + } qemu_iovec_to_buf(qiov, 0, buf, qiov->size); } else { orig_buf = NULL; @@ -685,7 +704,7 @@ static void qcow_close(BlockDriverState *bs) BDRVQcowState *s = bs->opaque; g_free(s->l1_table); - g_free(s->l2_cache); + qemu_vfree(s->l2_cache); g_free(s->cluster_cache); g_free(s->cluster_data); -- 1.8.3.1