Commit dafe0960 authored by Kevin Wolf's avatar Kevin Wolf
Browse files

block: Fix permissions in image activation 



Inactive images generally request less permissions for their image files
than they would if they were active (in particular, write permissions).
Activating the image involves extending the permissions, therefore.

drv->bdrv_invalidate_cache() can already require write access to the
image file, so we have to update the permissions earlier than that.
The current code does it only later, so we have to move up this part.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
parent f0603329

block.c

+22 −10
Original line number Diff line number Diff line
@@ -4174,7 +4174,29 @@ void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp) 
        }

    }



    /*

     * Update permissions, they may differ for inactive nodes.

     *

     * Note that the required permissions of inactive images are always a

     * subset of the permissions required after activating the image. This

     * allows us to just get the permissions upfront without restricting

     * drv->bdrv_invalidate_cache().

     *

     * It also means that in error cases, we don't have to try and revert to

     * the old permissions (which is an operation that could fail, too). We can

     * just keep the extended permissions for the next time that an activation

     * of the image is tried.

     */

    bs->open_flags &= ~BDRV_O_INACTIVE;

    bdrv_get_cumulative_perm(bs, &perm, &shared_perm);

    ret = bdrv_check_perm(bs, NULL, perm, shared_perm, NULL, &local_err);

    if (ret < 0) {

        bs->open_flags |= BDRV_O_INACTIVE;

        error_propagate(errp, local_err);

        return;

    }

    bdrv_set_perm(bs, perm, shared_perm);



    if (bs->drv->bdrv_invalidate_cache) {

        bs->drv->bdrv_invalidate_cache(bs, &local_err);

        if (local_err) {
@@ -4191,16 +4213,6 @@ void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp) 
        return;

    }



    /* Update permissions, they may differ for inactive nodes */

    bdrv_get_cumulative_perm(bs, &perm, &shared_perm);

    ret = bdrv_check_perm(bs, NULL, perm, shared_perm, NULL, &local_err);

    if (ret < 0) {

        bs->open_flags |= BDRV_O_INACTIVE;

        error_propagate(errp, local_err);

        return;

    }

    bdrv_set_perm(bs, perm, shared_perm);



    QLIST_FOREACH(parent, &bs->parents, next_parent) {

        if (parent->role->activate) {

            parent->role->activate(parent, &local_err);