dmg: 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 dmg 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 13:28:14 +02:00
parent 8dc7a7725b
commit b546a94474

View File

@ -284,8 +284,15 @@ static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
}
/* initialize zlib engine */
s->compressed_chunk = g_malloc(max_compressed_size + 1);
s->uncompressed_chunk = g_malloc(512 * max_sectors_per_chunk);
s->compressed_chunk = qemu_try_blockalign(bs->file,
max_compressed_size + 1);
s->uncompressed_chunk = qemu_try_blockalign(bs->file,
512 * max_sectors_per_chunk);
if (s->compressed_chunk == NULL || s->uncompressed_chunk == NULL) {
ret = -ENOMEM;
goto fail;
}
if (inflateInit(&s->zstream) != Z_OK) {
ret = -EINVAL;
goto fail;
@ -302,8 +309,8 @@ fail:
g_free(s->lengths);
g_free(s->sectors);
g_free(s->sectorcounts);
g_free(s->compressed_chunk);
g_free(s->uncompressed_chunk);
qemu_vfree(s->compressed_chunk);
qemu_vfree(s->uncompressed_chunk);
return ret;
}
@ -426,8 +433,8 @@ static void dmg_close(BlockDriverState *bs)
g_free(s->lengths);
g_free(s->sectors);
g_free(s->sectorcounts);
g_free(s->compressed_chunk);
g_free(s->uncompressed_chunk);
qemu_vfree(s->compressed_chunk);
qemu_vfree(s->uncompressed_chunk);
inflateEnd(&s->zstream);
}