Commit c9b83e9c authored by Alberto Garcia's avatar Alberto Garcia Committed by Max Reitz
Browse files

qcow2: Assert that the crypto header does not overlap other metadata 



The crypto header is initialized only when QEMU is creating a new
image, so there's no chance of this happening on a corrupted image.

If QEMU is really trying to allocate the header overlapping other
existing metadata sections then this is a serious bug in QEMU itself
so let's add an assertion.

Signed-off-by: default avatarAlberto Garcia <berto@igalia.com>
Message-id: ae3d77f312fc0c5e0ac2bbd71676c0112eebe2e5.1509718618.git.berto@igalia.com
Reviewed-by: default avatarDaniel P. Berrange <berrange@redhat.com>
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
parent ef083f61

block/qcow2.c

+1 −0
Original line number Diff line number Diff line
@@ -126,6 +126,7 @@ static ssize_t qcow2_crypto_hdr_init_func(QCryptoBlock *block, size_t headerlen, 
    /* Zero fill remaining space in cluster so it has predictable

     * content in case of future spec changes */

    clusterlen = size_to_clusters(s, headerlen) * s->cluster_size;

    assert(qcow2_pre_write_overlap_check(bs, 0, ret, clusterlen) == 0);

    ret = bdrv_pwrite_zeroes(bs->file,

                             ret + headerlen,

                             clusterlen - headerlen, 0);