From 17cce735780f0ff6a2ef173c34614bd47acd56e5 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Tue, 20 May 2014 13:25:43 +0200 Subject: vdi: Handle failure for potentially large allocations 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 vdi block driver. Signed-off-by: Kevin Wolf Reviewed-by: Stefan Hajnoczi Reviewed-by: Benoit Canet --- block/vdi.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) (limited to 'block') diff --git a/block/vdi.c b/block/vdi.c index 9d62a3cb97..adc6aa9a5f 100644 --- a/block/vdi.c +++ b/block/vdi.c @@ -292,7 +292,12 @@ static int vdi_check(BlockDriverState *bs, BdrvCheckResult *res, return -ENOTSUP; } - bmap = g_malloc(s->header.blocks_in_image * sizeof(uint32_t)); + bmap = g_try_malloc(s->header.blocks_in_image * sizeof(uint32_t)); + if (s->header.blocks_in_image && bmap == NULL) { + res->check_errors++; + return -ENOMEM; + } + memset(bmap, 0xff, s->header.blocks_in_image * sizeof(uint32_t)); /* Check block map and value of blocks_allocated. */ @@ -471,7 +476,12 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags, bmap_size = header.blocks_in_image * sizeof(uint32_t); bmap_size = (bmap_size + SECTOR_SIZE - 1) / SECTOR_SIZE; - s->bmap = g_malloc(bmap_size * SECTOR_SIZE); + s->bmap = qemu_try_blockalign(bs->file, bmap_size * SECTOR_SIZE); + if (s->bmap == NULL) { + ret = -ENOMEM; + goto fail; + } + ret = bdrv_read(bs->file, s->bmap_sector, (uint8_t *)s->bmap, bmap_size); if (ret < 0) { goto fail_free_bmap; @@ -486,7 +496,7 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags, return 0; fail_free_bmap: - g_free(s->bmap); + qemu_vfree(s->bmap); fail: return ret; @@ -760,7 +770,12 @@ static int vdi_create(const char *filename, QemuOpts *opts, Error **errp) offset += sizeof(header); if (bmap_size > 0) { - bmap = g_malloc0(bmap_size); + bmap = g_try_malloc0(bmap_size); + if (bmap == NULL) { + ret = -ENOMEM; + error_setg(errp, "Could not allocate bmap"); + goto exit; + } for (i = 0; i < blocks; i++) { if (image_type == VDI_TYPE_STATIC) { bmap[i] = i; @@ -794,7 +809,7 @@ static void vdi_close(BlockDriverState *bs) { BDRVVdiState *s = bs->opaque; - g_free(s->bmap); + qemu_vfree(s->bmap); migrate_del_blocker(s->migration_blocker); error_free(s->migration_blocker); -- cgit v1.2.1