diff mbox series

[10/10] qcow2-refcount: check_refblocks(): add separate message for reserved

Message ID 20210504152023.322862-11-vsementsov@virtuozzo.com
State New
Headers show
Series qcow2 check: check some reserved bits and subcluster bitmaps | expand

Commit Message

Vladimir Sementsov-Ogievskiy May 4, 2021, 3:20 p.m. UTC
Split checking for reserved bits out of aligned offset check.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/qcow2.h          |  1 +
 block/qcow2-refcount.c | 10 +++++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

Comments

Eric Blake May 4, 2021, 7:54 p.m. UTC | #1
On 5/4/21 10:20 AM, Vladimir Sementsov-Ogievskiy wrote:
> Split checking for reserved bits out of aligned offset check.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  block/qcow2.h          |  1 +
>  block/qcow2-refcount.c | 10 +++++++++-
>  2 files changed, 10 insertions(+), 1 deletion(-)

Reviewed-by: Eric Blake <eblake@redhat.com>
Vladimir Sementsov-Ogievskiy May 5, 2021, 6:36 a.m. UTC | #2
04.05.2021 22:54, Eric Blake wrote:
> On 5/4/21 10:20 AM, Vladimir Sementsov-Ogievskiy wrote:
>> Split checking for reserved bits out of aligned offset check.
>>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>> ---
>>   block/qcow2.h          |  1 +
>>   block/qcow2-refcount.c | 10 +++++++++-
>>   2 files changed, 10 insertions(+), 1 deletion(-)
> 
> Reviewed-by: Eric Blake <eblake@redhat.com>
> 

Thanks a lot for reviewing!
diff mbox series

Patch

diff --git a/block/qcow2.h b/block/qcow2.h
index 58fd7f1678..fd48a89d45 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -591,6 +591,7 @@  typedef enum QCow2MetadataOverlap {
 #define L2E_STD_RESERVED_MASK 0x3f000000000001feULL
 
 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
+#define REFT_RESERVED_MASK 0x1ffULL
 
 #define INV_OFFSET (-1ULL)
 
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 9a20aac0c9..9ae45efc75 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -2090,9 +2090,17 @@  static int check_refblocks(BlockDriverState *bs, BdrvCheckResult *res,
 
     for(i = 0; i < s->refcount_table_size; i++) {
         uint64_t offset, cluster;
-        offset = s->refcount_table[i];
+        offset = s->refcount_table[i] & REFT_OFFSET_MASK;
         cluster = offset >> s->cluster_bits;
 
+        if (s->refcount_table[i] & REFT_RESERVED_MASK) {
+            fprintf(stderr, "ERROR refcount table entry %" PRId64 " has "
+                    "reserved bits set\n", i);
+            res->corruptions++;
+            *rebuild = true;
+            continue;
+        }
+
         /* Refcount blocks are cluster aligned */
         if (offset_into_cluster(s, offset)) {
             fprintf(stderr, "ERROR refcount block %" PRId64 " is not "