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 <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
This commit is contained in:
Kevin Wolf 2014-05-20 13:25:43 +02:00
parent 0f7a02379b
commit 17cce73578
1 changed files with 20 additions and 5 deletions

View File

@ -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);