vmdk: Fix zero cluster allocation

m_data must contain valid data even for zero clusters when no cluster
was allocated in the image file. Without this, zero writes segfault with
images that have zeroed_grain=on.

For zero writes, we don't want to allocate a cluster in the image file
even in compressed files.

Fixes: 524089bce4
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200430133007.170335-3-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2020-04-30 15:30:03 +02:00
parent 4dc20e6465
commit 2821c1cc0f

View File

@ -1572,6 +1572,12 @@ static int get_cluster_offset(BlockDriverState *bs,
extent->l2_cache_counts[min_index] = 1;
found:
l2_index = ((offset >> 9) / extent->cluster_sectors) % extent->l2_size;
if (m_data) {
m_data->l1_index = l1_index;
m_data->l2_index = l2_index;
m_data->l2_offset = l2_offset;
m_data->l2_cache_entry = ((uint32_t *)l2_table) + l2_index;
}
if (extent->sesparse) {
cluster_sector = le64_to_cpu(((uint64_t *)l2_table)[l2_index]);
@ -1631,10 +1637,6 @@ static int get_cluster_offset(BlockDriverState *bs,
}
if (m_data) {
m_data->new_allocation = true;
m_data->l1_index = l1_index;
m_data->l2_index = l2_index;
m_data->l2_offset = l2_offset;
m_data->l2_cache_entry = ((uint32_t *)l2_table) + l2_index;
}
}
*cluster_offset = cluster_sector << BDRV_SECTOR_BITS;
@ -1990,7 +1992,7 @@ static int vmdk_pwritev(BlockDriverState *bs, uint64_t offset,
error_report("Could not write to allocated cluster"
" for streamOptimized");
return -EIO;
} else {
} else if (!zeroed) {
/* allocate */
ret = get_cluster_offset(bs, extent, &m_data, offset,
true, &cluster_offset, 0, 0);