diff options
author | Ilya Dryomov <idryomov@gmail.com> | 2017-04-13 13:17:37 +0300 |
---|---|---|
committer | Ilya Dryomov <idryomov@gmail.com> | 2017-05-04 10:19:23 +0300 |
commit | fd22aef8b47cfc068448df65c1183698b0abd815 (patch) | |
tree | bb0059af80d5aedb2c4b124eb3e1b23f1e40ffea /drivers/block | |
parent | 8b679ec5257eeb3d73b71a613cad2769f21c86ad (diff) | |
download | linux-fd22aef8b47cfc068448df65c1183698b0abd815.tar.xz |
rbd: move rbd_unregister_watch() call into rbd_dev_image_release()
rbd_dev->disk tear down vs rbd_watch_cb() race shouldn't be a problem
anymore thanks to EXISTS and REMOVING checks in rbd_dev_update_size().
A similar race could occur on "rbd map", see commit 811c66887746
("rbd: fix rbd map vs notify races").
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/rbd.c | 18 |
1 files changed, 3 insertions, 15 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 0191a3ca5460..b299ed0315f8 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -5964,6 +5964,8 @@ static int rbd_dev_header_name(struct rbd_device *rbd_dev) static void rbd_dev_image_release(struct rbd_device *rbd_dev) { rbd_dev_unprobe(rbd_dev); + if (rbd_dev->opts) + rbd_unregister_watch(rbd_dev); rbd_dev->image_format = 0; kfree(rbd_dev->spec->image_id); rbd_dev->spec->image_id = NULL; @@ -6126,15 +6128,8 @@ static ssize_t do_rbd_add(struct bus_type *bus, rbd_dev->mapping.read_only = read_only; rc = rbd_dev_device_setup(rbd_dev); - if (rc) { - /* - * rbd_unregister_watch() can't be moved into - * rbd_dev_image_release() without refactoring, see - * commit 1f3ef78861ac. - */ - rbd_unregister_watch(rbd_dev); + if (rc) goto err_out_image_probe; - } rc = count; out: @@ -6275,14 +6270,7 @@ static ssize_t do_rbd_remove(struct bus_type *bus, if (__rbd_is_lock_owner(rbd_dev)) rbd_unlock(rbd_dev); up_write(&rbd_dev->lock_rwsem); - rbd_unregister_watch(rbd_dev); - /* - * Don't free anything from rbd_dev->disk until after all - * notifies are completely processed. Otherwise - * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting - * in a potential use after free of rbd_dev->disk or rbd_dev. - */ rbd_dev_device_release(rbd_dev); rbd_dev_image_release(rbd_dev); rbd_dev_destroy(rbd_dev); |