diff --git a/block/raw-format.c b/block/raw-format.c index 7717578ed6..c26f493688 100644 --- a/block/raw-format.c +++ b/block/raw-format.c @@ -580,6 +580,25 @@ static void raw_cancel_in_flight(BlockDriverState *bs) bdrv_cancel_in_flight(bs->file->bs); } +static void raw_child_perm(BlockDriverState *bs, BdrvChild *c, + BdrvChildRole role, + BlockReopenQueue *reopen_queue, + uint64_t parent_perm, uint64_t parent_shared, + uint64_t *nperm, uint64_t *nshared) +{ + bdrv_default_perms(bs, c, role, reopen_queue, parent_perm, + parent_shared, nperm, nshared); + + /* + * bdrv_default_perms() may add WRITE and/or RESIZE (see comment in + * bdrv_default_perms_for_storage() for an explanation) but we only need + * them if they are in parent_perm. Drop WRITE and RESIZE whenever possible + * to avoid permission conflicts. + */ + *nperm &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); + *nperm |= parent_perm & (BLK_PERM_WRITE | BLK_PERM_RESIZE); +} + BlockDriver bdrv_raw = { .format_name = "raw", .instance_size = sizeof(BDRVRawState), @@ -588,7 +607,7 @@ BlockDriver bdrv_raw = { .bdrv_reopen_commit = &raw_reopen_commit, .bdrv_reopen_abort = &raw_reopen_abort, .bdrv_open = &raw_open, - .bdrv_child_perm = bdrv_default_perms, + .bdrv_child_perm = raw_child_perm, .bdrv_co_create_opts = &raw_co_create_opts, .bdrv_co_preadv = &raw_co_preadv, .bdrv_co_pwritev = &raw_co_pwritev,