From e54def4ad8144ab15f826416e2e0f290ef1901b4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 19 Jun 2024 23:00:30 +0200 Subject: Adding upstream version 6.9.2. Signed-off-by: Daniel Baumann --- net/ipv4/fib_frontend.c | 56 +++++++++++++++++++++++++++---------------------- 1 file changed, 31 insertions(+), 25 deletions(-) (limited to 'net/ipv4/fib_frontend.c') diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 390f4be7f7..c484b1c0fc 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -916,7 +916,8 @@ int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, struct rtmsg *rtm; int err, i; - ASSERT_RTNL(); + if (filter->rtnl_held) + ASSERT_RTNL(); if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) { NL_SET_ERR_MSG(extack, "Invalid header for FIB dump request"); @@ -961,7 +962,10 @@ int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, break; case RTA_OIF: ifindex = nla_get_u32(tb[i]); - filter->dev = __dev_get_by_index(net, ifindex); + if (filter->rtnl_held) + filter->dev = __dev_get_by_index(net, ifindex); + else + filter->dev = dev_get_by_index_rcu(net, ifindex); if (!filter->dev) return -ENODEV; break; @@ -983,20 +987,24 @@ EXPORT_SYMBOL_GPL(ip_valid_fib_dump_req); static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) { - struct fib_dump_filter filter = { .dump_routes = true, - .dump_exceptions = true }; + struct fib_dump_filter filter = { + .dump_routes = true, + .dump_exceptions = true, + .rtnl_held = false, + }; const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); unsigned int h, s_h; unsigned int e = 0, s_e; struct fib_table *tb; struct hlist_head *head; - int dumped = 0, err; + int dumped = 0, err = 0; + rcu_read_lock(); if (cb->strict_check) { err = ip_valid_fib_dump_req(net, nlh, &filter, cb); if (err < 0) - return err; + goto unlock; } else if (nlmsg_len(nlh) >= sizeof(struct rtmsg)) { struct rtmsg *rtm = nlmsg_data(nlh); @@ -1005,29 +1013,26 @@ static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) /* ipv4 does not use prefix flag */ if (filter.flags & RTM_F_PREFIX) - return skb->len; + goto unlock; if (filter.table_id) { tb = fib_get_table(net, filter.table_id); if (!tb) { if (rtnl_msg_family(cb->nlh) != PF_INET) - return skb->len; + goto unlock; NL_SET_ERR_MSG(cb->extack, "ipv4: FIB table does not exist"); - return -ENOENT; + err = -ENOENT; + goto unlock; } - - rcu_read_lock(); err = fib_table_dump(tb, skb, cb, &filter); - rcu_read_unlock(); - return skb->len ? : err; + goto unlock; } s_h = cb->args[0]; s_e = cb->args[1]; - rcu_read_lock(); - + err = 0; for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { e = 0; head = &net->ipv4.fib_table_hash[h]; @@ -1038,25 +1043,25 @@ static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) memset(&cb->args[2], 0, sizeof(cb->args) - 2 * sizeof(cb->args[0])); err = fib_table_dump(tb, skb, cb, &filter); - if (err < 0) { - if (likely(skb->len)) - goto out; - - goto out_err; - } + if (err < 0) + goto out; dumped = 1; next: e++; } } -out: + + /* Don't let NLM_DONE coalesce into a message, even if it could. + * Some user space expects NLM_DONE in a separate recv(). + */ err = skb->len; -out_err: - rcu_read_unlock(); +out: cb->args[1] = e; cb->args[0] = h; +unlock: + rcu_read_unlock(); return err; } @@ -1659,5 +1664,6 @@ void __init ip_fib_init(void) rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, 0); rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, 0); - rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, 0); + rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, + RTNL_FLAG_DUMP_UNLOCKED); } -- cgit v1.2.3