5.4-stable review patch. If anyone has any objections, please let me know.
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From: Nikolay Aleksandrov razor@blackwall.org
[ Upstream commit a6cec0bcd34264be8887791594be793b3f12719f ]
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 dsahern@kernel.org Signed-off-by: Nikolay Aleksandrov razor@blackwall.org Signed-off-by: David S. Miller davem@davemloft.net Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace") Signed-off-by: Sasha Levin sashal@kernel.org --- 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 030fc7eef7401..e893b1f21913e 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 b41f31a09a7cd..c4b33a2ecac26 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -214,6 +214,8 @@ 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 */ @@ -5274,6 +5276,12 @@ 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();