| Message ID | 18b57f7b-6aa6-e87f-e187-feead42fc90a@ugent.be (mailing list archive) |
|---|---|
| State | Rejected |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | devlink: use devlink lock on DEVLINK_CMD_PORT_SPLIT | expand |
On Mon, 21 Feb 2022 14:33:25 +0100 Niels Dossche wrote: > devlink_nl_cmd_port_split_doit is executed without taking the devlink > instance lock. This function calls to devlink_port_get_from_info, which > calls devlink_port_get_from_attrs, which calls > devlink_port_get_by_index, which accesses devlink->port_list without the > instance lock taken, while in other places devlink->port_list access > always happens with the instance lock taken. The documentation in the > struct also say that the devlink lock protects the port_list. > > The flag for no locking was added after refactoring the code to no > longer use a global lock. > > Fixes: 2406e7e546b2 ("devlink: Add per devlink instance lock") > Signed-off-by: Niels Dossche <niels.dossche@ugent.be> You can't do this, driver will likely try to register ports and try to re-acquire the same lock. I have a series queued to fix this by moving the locking into drivers. I'll send it out this week.
diff --git a/net/core/devlink.c b/net/core/devlink.c index fcd9f6d85cf1..563becaa03a6 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -8645,7 +8645,6 @@ static const struct genl_small_ops devlink_nl_ops[] = { .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = devlink_nl_cmd_port_split_doit, .flags = GENL_ADMIN_PERM, - .internal_flags = DEVLINK_NL_FLAG_NO_LOCK, }, { .cmd = DEVLINK_CMD_PORT_UNSPLIT,
devlink_nl_cmd_port_split_doit is executed without taking the devlink instance lock. This function calls to devlink_port_get_from_info, which calls devlink_port_get_from_attrs, which calls devlink_port_get_by_index, which accesses devlink->port_list without the instance lock taken, while in other places devlink->port_list access always happens with the instance lock taken. The documentation in the struct also say that the devlink lock protects the port_list. The flag for no locking was added after refactoring the code to no longer use a global lock. Fixes: 2406e7e546b2 ("devlink: Add per devlink instance lock") Signed-off-by: Niels Dossche <niels.dossche@ugent.be> --- net/core/devlink.c | 1 - 1 file changed, 1 deletion(-)