From 4d54cc32112d8d8b0667559c9309f1a6f764f70b Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 12 Feb 2021 15:59:59 -0800 Subject: mptcp: avoid lock_fast usage in accept path Once event support is added this may need to allocate memory while msk lock is held with softirqs disabled. Not using lock_fast also allows to do the allocation with GFP_KERNEL. Signed-off-by: Florian Westphal Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/netlink/genetlink.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) (limited to 'net/netlink') diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index c992424e4d63..2d6fdf40df66 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -1360,11 +1360,43 @@ static struct genl_family genl_ctrl __ro_after_init = { .netnsok = true, }; +static int genl_bind(struct net *net, int group) +{ + const struct genl_family *family; + unsigned int id; + int ret = 0; + + genl_lock_all(); + + idr_for_each_entry(&genl_fam_idr, family, id) { + const struct genl_multicast_group *grp; + int i; + + if (family->n_mcgrps == 0) + continue; + + i = group - family->mcgrp_offset; + if (i < 0 || i >= family->n_mcgrps) + continue; + + grp = &family->mcgrps[i]; + if ((grp->flags & GENL_UNS_ADMIN_PERM) && + !ns_capable(net->user_ns, CAP_NET_ADMIN)) + ret = -EPERM; + + break; + } + + genl_unlock_all(); + return ret; +} + static int __net_init genl_pernet_init(struct net *net) { struct netlink_kernel_cfg cfg = { .input = genl_rcv, .flags = NL_CFG_F_NONROOT_RECV, + .bind = genl_bind, }; /* we'll bump the group number right afterwards */ -- cgit v1.2.3