Place data_start/data_end calculation after reading the image header
to s->header. Set s->data_start to the offset calculated in
parallels_test_data_off(). Call bdrv_check() if data_off is incorrect.

Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
---
 block/parallels.c | 31 +++++++++++++++++--------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/block/parallels.c b/block/parallels.c
index 103acb7b40..48c32d6821 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -1032,9 +1032,11 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
     ParallelsHeader ph;
     int ret, size, i;
     int64_t file_nb_sectors, sector;
+    uint32_t data_start;
     QemuOpts *opts = NULL;
     Error *local_err = NULL;
     char *buf;
+    bool data_off_is_correct;
 
     ret = bdrv_open_file_child(NULL, options, "file", bs, errp);
     if (ret < 0) {
@@ -1092,10 +1094,20 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
         ret = -ENOMEM;
         goto fail;
     }
-    s->data_start = le32_to_cpu(ph.data_off);
-    if (s->data_start == 0) {
-        s->data_start = DIV_ROUND_UP(size, BDRV_SECTOR_SIZE);
+
+    ret = bdrv_pread(bs->file, 0, s->header_size, s->header, 0);
+    if (ret < 0) {
+        goto fail;
     }
+    s->bat_bitmap = (uint32_t *)(s->header + 1);
+
+    if (le32_to_cpu(ph.inuse) == HEADER_INUSE_MAGIC) {
+        s->header_unclean = true;
+    }
+
+    data_off_is_correct = parallels_test_data_off(s, file_nb_sectors,
+                                                  &data_start);
+    s->data_start = data_start;
     s->data_end = s->data_start;
     if (s->data_end < (s->header_size >> BDRV_SECTOR_BITS)) {
         /*
@@ -1105,16 +1117,6 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
         s->header_size = size;
     }
 
-    ret = bdrv_pread(bs->file, 0, s->header_size, s->header, 0);
-    if (ret < 0) {
-        goto fail;
-    }
-    s->bat_bitmap = (uint32_t *)(s->header + 1);
-
-    if (le32_to_cpu(ph.inuse) == HEADER_INUSE_MAGIC) {
-        s->header_unclean = true;
-    }
-
     opts = qemu_opts_create(&parallels_runtime_opts, NULL, 0, errp);
     if (!opts) {
         goto fail_options;
@@ -1197,7 +1199,8 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
      * Repair the image if it's dirty or
      * out-of-image corruption was detected.
      */
-    if (s->data_end > file_nb_sectors || s->header_unclean) {
+    if (s->data_end > file_nb_sectors || s->header_unclean
+        || !data_off_is_correct) {
         BdrvCheckResult res;
         ret = bdrv_check(bs, &res, BDRV_FIX_ERRORS | BDRV_FIX_LEAKS);
         if (ret < 0) {
-- 
2.34.1