qcow2: Add plausibility check for L1/L2 entries (Kevin Wolf)

From: Kevin Wolf <kwolf@redhat.com>

All L1 and L2 entries must point at the start of a cluster. If there is some
offset into the cluster, the entry is corrupted.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7217 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aliguori 2009-04-21 23:12:02 +00:00
parent ae2f14af54
commit 54c42368f5

View File

@ -2666,6 +2666,13 @@ static int check_refcounts_l2(BlockDriverState *bs,
errors += inc_refcounts(bs, refcount_table,
refcount_table_size,
offset, s->cluster_size);
/* Correct offsets are cluster aligned */
if (offset & (s->cluster_size - 1)) {
fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not "
"properly aligned; L2 entry corrupted.\n", offset);
errors++;
}
}
}
}
@ -2734,6 +2741,13 @@ static int check_refcounts_l1(BlockDriverState *bs,
l2_offset,
s->cluster_size);
/* L2 tables are cluster aligned */
if (l2_offset & (s->cluster_size - 1)) {
fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not "
"cluster aligned; L1 entry corrupted\n", l2_offset);
errors++;
}
/* Process and check L2 entries */
ret = check_refcounts_l2(bs, refcount_table, refcount_table_size,
l2_offset, check_copied);