From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45430) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YKty5-0005WW-2d for qemu-devel@nongnu.org; Mon, 09 Feb 2015 14:26:01 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YKty3-0003Tj-T0 for qemu-devel@nongnu.org; Mon, 09 Feb 2015 14:26:01 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36586) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YKty3-0003TF-EP for qemu-devel@nongnu.org; Mon, 09 Feb 2015 14:25:59 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t19JPwdt014434 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Mon, 9 Feb 2015 14:25:58 -0500 From: Max Reitz Date: Mon, 9 Feb 2015 14:25:44 -0500 Message-Id: <1423509950-7468-7-git-send-email-mreitz@redhat.com> In-Reply-To: <1423509950-7468-1-git-send-email-mreitz@redhat.com> References: <1423509950-7468-1-git-send-email-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v3 06/12] qcow2/overlaps: Protect refcount blocks List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , Max Reitz Keep track of the refcount blocks in the metadata list to protect them against accidental modifications. Signed-off-by: Max Reitz Reviewed-by: Eric Blake --- block/qcow2-refcount.c | 38 +++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index ea08673..a785027 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -57,8 +57,16 @@ int qcow2_refcount_init(BlockDriverState *bs) if (ret < 0) { goto fail; } - for(i = 0; i < s->refcount_table_size; i++) + for (i = 0; i < s->refcount_table_size; i++) { + uint64_t refblock_offset; + be64_to_cpus(&s->refcount_table[i]); + refblock_offset = s->refcount_table[i] & REFT_OFFSET_MASK; + if (refblock_offset) { + qcow2_metadata_list_enter(bs, refblock_offset, 1, + QCOW2_OL_REFCOUNT_BLOCK); + } + } } return 0; fail: @@ -302,6 +310,7 @@ static int alloc_refcount_block(BlockDriverState *bs, } s->refcount_table[refcount_table_index] = new_block; + qcow2_metadata_list_enter(bs, new_block, 1, QCOW2_OL_REFCOUNT_BLOCK); /* The new refcount block may be where the caller intended to put its * data, so let it restart the search. */ @@ -363,6 +372,7 @@ static int alloc_refcount_block(BlockDriverState *bs, uint64_t table_offset = meta_offset + blocks_clusters * s->cluster_size; uint64_t *new_table = g_try_new0(uint64_t, table_size); uint16_t *new_blocks = g_try_malloc0(blocks_clusters * s->cluster_size); + uint64_t block_index; assert(table_size > 0 && blocks_clusters > 0); if (new_table == NULL || new_blocks == NULL) { @@ -441,6 +451,12 @@ static int alloc_refcount_block(BlockDriverState *bs, qcow2_metadata_list_enter(bs, table_offset, table_clusters, QCOW2_OL_REFCOUNT_TABLE); + for (block_index = 0; block_index < blocks_clusters; block_index++) { + qcow2_metadata_list_enter(bs, meta_offset + + (block_index << s->cluster_bits), 1, + QCOW2_OL_REFCOUNT_BLOCK); + } + /* Free old table. */ qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t), QCOW2_DISCARD_OTHER); @@ -1961,14 +1977,34 @@ write_refblocks: * sizeof(uint64_t)), QCOW2_OL_REFCOUNT_TABLE); + for (refblock_index = 0; refblock_index < s->refcount_table_size; + refblock_index++) + { + uint64_t refblock_offset = s->refcount_table[refblock_index] & + REFT_OFFSET_MASK; + if (refblock_offset) { + qcow2_metadata_list_remove(bs, refblock_offset, 1, + QCOW2_OL_REFCOUNT_BLOCK); + } + } + qcow2_metadata_list_enter(bs, reftable_offset, size_to_clusters(s, reftable_size * sizeof(uint64_t)), QCOW2_OL_REFCOUNT_TABLE); for (refblock_index = 0; refblock_index < reftable_size; refblock_index++) { + uint64_t refblock_offset; + be64_to_cpus(&on_disk_reftable[refblock_index]); + + refblock_offset = on_disk_reftable[refblock_index] & REFT_OFFSET_MASK; + if (refblock_offset) { + qcow2_metadata_list_enter(bs, refblock_offset, 1, + QCOW2_OL_REFCOUNT_BLOCK); + } } + s->refcount_table = on_disk_reftable; s->refcount_table_offset = reftable_offset; s->refcount_table_size = reftable_size; -- 2.1.0