| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20240227092411.2315725-4-edumazet@google.com>
Date: Tue, 27 Feb 2024 09:24:11 +0000
From: Eric Dumazet <edumazet@...gle.com>
To: "David S . Miller" <davem@...emloft.net>, Jakub Kicinski <kuba@...nel.org>,
Paolo Abeni <pabeni@...hat.com>
Cc: David Ahern <dsahern@...nel.org>, Jiri Pirko <jiri@...dia.com>, netdev@...r.kernel.org,
eric.dumazet@...il.com, Eric Dumazet <edumazet@...gle.com>
Subject: [PATCH net-next 3/3] inet: use xa_array iterator to implement inet_netconf_dump_devconf()
1) inet_netconf_dump_devconf() can run under RCU protection
instead of RTNL.
2) properly return 0 at the end of a dump, avoiding an
an extra recvmsg() system call.
3) Do not use inet_base_seq() anymore, for_each_netdev_dump()
has nice properties. Restarting a GETDEVCONF dump if a device has
been added/removed or if net->ipv4.dev_addr_genid has changed is moot.
Signed-off-by: Eric Dumazet <edumazet@...gle.com>
---
net/ipv4/devinet.c | 101 +++++++++++++++++++--------------------------
1 file changed, 43 insertions(+), 58 deletions(-)
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index f045a34e90b974b17512a30c3b719bdfc3cba153..af741af61830aeb695e7e75608515547dade8f39 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -2267,11 +2267,13 @@ static int inet_netconf_dump_devconf(struct sk_buff *skb,
{
const struct nlmsghdr *nlh = cb->nlh;
struct net *net = sock_net(skb->sk);
- int h, s_h;
- int idx, s_idx;
+ struct {
+ unsigned long ifindex;
+ unsigned int all_default;
+ } *ctx = (void *)cb->ctx;
+ const struct in_device *in_dev;
struct net_device *dev;
- struct in_device *in_dev;
- struct hlist_head *head;
+ int err = 0;
if (cb->strict_check) {
struct netlink_ext_ack *extack = cb->extack;
@@ -2288,64 +2290,47 @@ static int inet_netconf_dump_devconf(struct sk_buff *skb,
}
}
- s_h = cb->args[0];
- s_idx = idx = cb->args[1];
-
- for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
- idx = 0;
- head = &net->dev_index_head[h];
- rcu_read_lock();
- cb->seq = inet_base_seq(net);
- hlist_for_each_entry_rcu(dev, head, index_hlist) {
- if (idx < s_idx)
- goto cont;
- in_dev = __in_dev_get_rcu(dev);
- if (!in_dev)
- goto cont;
-
- if (inet_netconf_fill_devconf(skb, dev->ifindex,
- &in_dev->cnf,
- NETLINK_CB(cb->skb).portid,
- nlh->nlmsg_seq,
- RTM_NEWNETCONF,
- NLM_F_MULTI,
- NETCONFA_ALL) < 0) {
- rcu_read_unlock();
- goto done;
- }
- nl_dump_check_consistent(cb, nlmsg_hdr(skb));
-cont:
- idx++;
- }
- rcu_read_unlock();
+ rcu_read_lock();
+ for_each_netdev_dump(net, dev, ctx->ifindex) {
+ in_dev = __in_dev_get_rcu(dev);
+ if (!in_dev)
+ continue;
+ err = inet_netconf_fill_devconf(skb, dev->ifindex,
+ &in_dev->cnf,
+ NETLINK_CB(cb->skb).portid,
+ nlh->nlmsg_seq,
+ RTM_NEWNETCONF, NLM_F_MULTI,
+ NETCONFA_ALL);
+ if (err < 0)
+ goto done;
}
- if (h == NETDEV_HASHENTRIES) {
- if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
- net->ipv4.devconf_all,
- NETLINK_CB(cb->skb).portid,
- nlh->nlmsg_seq,
- RTM_NEWNETCONF, NLM_F_MULTI,
- NETCONFA_ALL) < 0)
+ if (ctx->all_default == 0) {
+ err = inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
+ net->ipv4.devconf_all,
+ NETLINK_CB(cb->skb).portid,
+ nlh->nlmsg_seq,
+ RTM_NEWNETCONF, NLM_F_MULTI,
+ NETCONFA_ALL);
+ if (err < 0)
goto done;
- else
- h++;
- }
- if (h == NETDEV_HASHENTRIES + 1) {
- if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
- net->ipv4.devconf_dflt,
- NETLINK_CB(cb->skb).portid,
- nlh->nlmsg_seq,
- RTM_NEWNETCONF, NLM_F_MULTI,
- NETCONFA_ALL) < 0)
+ ctx->all_default++;
+ }
+ if (ctx->all_default == 1) {
+ err = inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
+ net->ipv4.devconf_dflt,
+ NETLINK_CB(cb->skb).portid,
+ nlh->nlmsg_seq,
+ RTM_NEWNETCONF, NLM_F_MULTI,
+ NETCONFA_ALL);
+ if (err < 0)
goto done;
- else
- h++;
+ ctx->all_default++;
}
done:
- cb->args[0] = h;
- cb->args[1] = idx;
-
- return skb->len;
+ if (err < 0 && likely(skb->len))
+ err = skb->len;
+ rcu_read_unlock();
+ return err;
}
#ifdef CONFIG_SYSCTL
@@ -2829,5 +2814,5 @@ void __init devinet_init(void)
rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, 0);
rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf,
inet_netconf_dump_devconf,
- RTNL_FLAG_DOIT_UNLOCKED);
+ RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED);
}
--
2.44.0.rc1.240.g4c46232300-goog
Powered by blists - more mailing lists