qcow2: Ignore reserved bits in check_refcounts
Also don't infer the cluster type directly from the L2 entries, but use
qcow2_get_cluster_type() to keep everything in a single place.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index e0854dc..0112cc3 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -940,7 +940,7 @@
int check_copied)
{
BDRVQcowState *s = bs->opaque;
- uint64_t *l2_table, offset;
+ uint64_t *l2_table, l2_entry;
int i, l2_size, nb_csectors, refcount;
/* Read L2 table from disk */
@@ -952,54 +952,64 @@
/* Do the actual checks */
for(i = 0; i < s->l2_size; i++) {
- offset = be64_to_cpu(l2_table[i]);
- if (offset != 0) {
- if (offset & QCOW_OFLAG_COMPRESSED) {
- /* Compressed clusters don't have QCOW_OFLAG_COPIED */
- if (offset & QCOW_OFLAG_COPIED) {
- fprintf(stderr, "ERROR: cluster %" PRId64 ": "
- "copied flag must never be set for compressed "
- "clusters\n", offset >> s->cluster_bits);
- offset &= ~QCOW_OFLAG_COPIED;
- res->corruptions++;
+ l2_entry = be64_to_cpu(l2_table[i]);
+
+ switch (qcow2_get_cluster_type(l2_entry)) {
+ case QCOW2_CLUSTER_COMPRESSED:
+ /* Compressed clusters don't have QCOW_OFLAG_COPIED */
+ if (l2_entry & QCOW_OFLAG_COPIED) {
+ fprintf(stderr, "ERROR: cluster %" PRId64 ": "
+ "copied flag must never be set for compressed "
+ "clusters\n", l2_entry >> s->cluster_bits);
+ l2_entry &= ~QCOW_OFLAG_COPIED;
+ res->corruptions++;
+ }
+
+ /* Mark cluster as used */
+ nb_csectors = ((l2_entry >> s->csize_shift) &
+ s->csize_mask) + 1;
+ l2_entry &= s->cluster_offset_mask;
+ inc_refcounts(bs, res, refcount_table, refcount_table_size,
+ l2_entry & ~511, nb_csectors * 512);
+ break;
+
+ case QCOW2_CLUSTER_NORMAL:
+ {
+ /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
+ uint64_t offset = l2_entry & L2E_OFFSET_MASK;
+
+ if (check_copied) {
+ refcount = get_refcount(bs, offset >> s->cluster_bits);
+ if (refcount < 0) {
+ fprintf(stderr, "Can't get refcount for offset %"
+ PRIx64 ": %s\n", l2_entry, strerror(-refcount));
+ goto fail;
}
-
- /* Mark cluster as used */
- nb_csectors = ((offset >> s->csize_shift) &
- s->csize_mask) + 1;
- offset &= s->cluster_offset_mask;
- inc_refcounts(bs, res, refcount_table, refcount_table_size,
- offset & ~511, nb_csectors * 512);
- } else {
- /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
- if (check_copied) {
- uint64_t entry = offset;
- offset &= ~QCOW_OFLAG_COPIED;
- refcount = get_refcount(bs, offset >> s->cluster_bits);
- if (refcount < 0) {
- fprintf(stderr, "Can't get refcount for offset %"
- PRIx64 ": %s\n", entry, strerror(-refcount));
- goto fail;
- }
- if ((refcount == 1) != ((entry & QCOW_OFLAG_COPIED) != 0)) {
- fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
- PRIx64 " refcount=%d\n", entry, refcount);
- res->corruptions++;
- }
- }
-
- /* Mark cluster as used */
- offset &= ~QCOW_OFLAG_COPIED;
- inc_refcounts(bs, res, 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);
+ if ((refcount == 1) != ((l2_entry & QCOW_OFLAG_COPIED) != 0)) {
+ fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
+ PRIx64 " refcount=%d\n", l2_entry, refcount);
res->corruptions++;
}
}
+
+ /* Mark cluster as used */
+ inc_refcounts(bs, res, 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);
+ res->corruptions++;
+ }
+ break;
+ }
+
+ case QCOW2_CLUSTER_UNALLOCATED:
+ break;
+
+ default:
+ abort();
}
}
@@ -1070,7 +1080,7 @@
}
/* Mark L2 table as used */
- l2_offset &= ~QCOW_OFLAG_COPIED;
+ l2_offset &= L1E_OFFSET_MASK;
inc_refcounts(bs, res, refcount_table, refcount_table_size,
l2_offset, s->cluster_size);