d6169b0206
The capability check should not be audited since it is only being used
to determine the inode permissions. A failed check does not indicate a
violation of security policy but, when an LSM is enabled, a denial audit
message was being generated.
The denial audit message caused confusion for some application authors
because root-running Go applications always triggered the denial. To
prevent this confusion, the capability check in net_ctl_permissions() is
switched to the noaudit variant.
BugLink: https://launchpad.net/bugs/1465724
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
[dtor: reapplied after e79c6a4fc9 ("net: make net namespace sysctls
belong to container's owner") accidentally reverted the change.]
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
129 lines
3 KiB
C
129 lines
3 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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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_header *head,
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struct ctl_table *table)
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{
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struct net *net = container_of(head->set, struct net, sysctls);
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/* Allow network administrator to have same access as root. */
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if (ns_capable_noaudit(net->user_ns, 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 void net_ctl_set_ownership(struct ctl_table_header *head,
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struct ctl_table *table,
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kuid_t *uid, kgid_t *gid)
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{
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struct net *net = container_of(head->set, struct net, sysctls);
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kuid_t ns_root_uid;
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kgid_t ns_root_gid;
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ns_root_uid = make_kuid(net->user_ns, 0);
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if (uid_valid(ns_root_uid))
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*uid = ns_root_uid;
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ns_root_gid = make_kgid(net->user_ns, 0);
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if (gid_valid(ns_root_gid))
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*gid = ns_root_gid;
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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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.set_ownership = net_ctl_set_ownership,
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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 out1;
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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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out1:
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unregister_sysctl_table(net_header);
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net_header = NULL;
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goto out;
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}
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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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