![Eric W. Biederman](/assets/img/avatar_default.png)
register_sysctl_rotable never caught on as an interesting way to register sysctls. My take on the situation is that what we want are sysctls that we can only see in the initial network namespace. What we have implemented with register_sysctl_rotable are sysctls that we can see in all of the network namespaces and can only change in the initial network namespace. That is a very silly way to go. Just register the network sysctls in the initial network namespace and we don't have any weird special cases to deal with. The sysctls affected are: /proc/sys/net/ipv4/ipfrag_secret_interval /proc/sys/net/ipv4/ipfrag_max_dist /proc/sys/net/ipv6/ip6frag_secret_interval /proc/sys/net/ipv6/mld_max_msf I really don't expect anyone will miss them if they can't read them in a child user namespace. CC: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
117 lines
2.7 KiB
C
117 lines
2.7 KiB
C
/* -*- linux-c -*-
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* sysctl_net.c: sysctl interface to net subsystem.
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*
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* Begun April 1, 1996, Mike Shaver.
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* Added /proc/sys/net directories for each protocol family. [MS]
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*
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* Revision 1.2 1996/05/08 20:24:40 shaver
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* Added bits for NET_BRIDGE and the NET_IPV4_ARP stuff and
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* NET_IPV4_IP_FORWARD.
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*
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*
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*/
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#include <linux/mm.h>
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#include <linux/export.h>
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#include <linux/sysctl.h>
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#include <linux/nsproxy.h>
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#include <net/sock.h>
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#ifdef CONFIG_INET
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#include <net/ip.h>
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#endif
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#ifdef CONFIG_NET
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#include <linux/if_ether.h>
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#endif
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#ifdef CONFIG_TR
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#include <linux/if_tr.h>
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#endif
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static struct ctl_table_set *
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net_ctl_header_lookup(struct ctl_table_root *root, struct nsproxy *namespaces)
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{
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return &namespaces->net_ns->sysctls;
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}
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static int is_seen(struct ctl_table_set *set)
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{
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return ¤t->nsproxy->net_ns->sysctls == set;
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}
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/* Return standard mode bits for table entry. */
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static int net_ctl_permissions(struct ctl_table_root *root,
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struct nsproxy *nsproxy,
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struct ctl_table *table)
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{
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/* Allow network administrator to have same access as root. */
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if (capable(CAP_NET_ADMIN)) {
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int mode = (table->mode >> 6) & 7;
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return (mode << 6) | (mode << 3) | mode;
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}
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return table->mode;
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}
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static struct ctl_table_root net_sysctl_root = {
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.lookup = net_ctl_header_lookup,
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.permissions = net_ctl_permissions,
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};
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static int __net_init sysctl_net_init(struct net *net)
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{
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setup_sysctl_set(&net->sysctls, &net_sysctl_root, is_seen);
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return 0;
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}
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static void __net_exit sysctl_net_exit(struct net *net)
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{
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retire_sysctl_set(&net->sysctls);
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}
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static struct pernet_operations sysctl_pernet_ops = {
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.init = sysctl_net_init,
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.exit = sysctl_net_exit,
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};
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static struct ctl_table_header *net_header;
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__init int net_sysctl_init(void)
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{
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static struct ctl_table empty[1];
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int ret = -ENOMEM;
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/* Avoid limitations in the sysctl implementation by
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* registering "/proc/sys/net" as an empty directory not in a
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* network namespace.
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*/
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net_header = register_sysctl("net", empty);
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if (!net_header)
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goto out;
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ret = register_pernet_subsys(&sysctl_pernet_ops);
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if (ret)
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goto out;
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register_sysctl_root(&net_sysctl_root);
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out:
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return ret;
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}
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struct ctl_table_header *register_net_sysctl_table(struct net *net,
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const struct ctl_path *path, struct ctl_table *table)
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{
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return __register_sysctl_paths(&net->sysctls, path, table);
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}
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EXPORT_SYMBOL_GPL(register_net_sysctl_table);
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struct ctl_table_header *register_net_sysctl(struct net *net,
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const char *path, struct ctl_table *table)
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{
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return __register_sysctl_table(&net->sysctls, path, table);
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}
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EXPORT_SYMBOL_GPL(register_net_sysctl);
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void unregister_net_sysctl_table(struct ctl_table_header *header)
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{
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unregister_sysctl_table(header);
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}
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EXPORT_SYMBOL_GPL(unregister_net_sysctl_table);
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