Add a new rtnl flag (RTNL_FLAG_BULK_DEL_SUPPORTED) which is used to verify that the delete operation allows bulk object deletion. Also emit a warning if anyone tries to set it for non-delete kind.
Suggested-by: David Ahern <[email protected]> Signed-off-by: Nikolay Aleksandrov <[email protected]> --- v4: new patch include/net/rtnetlink.h | 3 ++- net/core/rtnetlink.c | 8 ++++++++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h index 0bf622409aaa..bf8bb3357825 100644 --- a/include/net/rtnetlink.h +++ b/include/net/rtnetlink.h @@ -10,7 +10,8 @@ typedef int (*rtnl_doit_func)(struct sk_buff *, struct nlmsghdr *, typedef int (*rtnl_dumpit_func)(struct sk_buff *, struct netlink_callback *); enum rtnl_link_flags { - RTNL_FLAG_DOIT_UNLOCKED = BIT(0), + RTNL_FLAG_DOIT_UNLOCKED = BIT(0), + RTNL_FLAG_BULK_DEL_SUPPORTED = BIT(1), }; enum rtnl_kinds { diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index beda4a7da062..63c7df52a667 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -249,6 +249,8 @@ static int rtnl_register_internal(struct module *owner, if (dumpit) link->dumpit = dumpit; + WARN_ON(rtnl_msgtype_kind(msgtype) != RTNL_KIND_DEL && + (flags & RTNL_FLAG_BULK_DEL_SUPPORTED)); link->flags |= flags; /* publish protocol:msgtype */ @@ -6009,6 +6011,12 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, } flags = link->flags; + if (kind == RTNL_KIND_DEL && (nlh->nlmsg_flags & NLM_F_BULK) && + !(flags & RTNL_FLAG_BULK_DEL_SUPPORTED)) { + NL_SET_ERR_MSG(extack, "Bulk delete is not supported"); + goto err_unlock; + } + if (flags & RTNL_FLAG_DOIT_UNLOCKED) { doit = link->doit; rcu_read_unlock(); -- 2.35.1
