Skip to content

Commit

Permalink
inet: Register fragmentation some ctls at read-only root.
Browse files Browse the repository at this point in the history
Parts of fragments-related sysctls are read-only, but this is
done by cloning all the tables and dropping write-bits from
mode. Do the same but with read-only root.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
Pavel Emelyanov authored and David S. Miller committed May 19, 2008
1 parent 0002c63 commit 7d291eb
Show file tree
Hide file tree
Showing 2 changed files with 48 additions and 3 deletions.
16 changes: 14 additions & 2 deletions net/ipv4/ip_fragment.c
Original file line number Diff line number Diff line change
Expand Up @@ -624,6 +624,10 @@ static struct ctl_table ip4_frags_ns_ctl_table[] = {
.proc_handler = &proc_dointvec_jiffies,
.strategy = &sysctl_jiffies
},
{ }
};

static struct ctl_table ip4_frags_ctl_table[] = {
{
.ctl_name = NET_IPV4_IPFRAG_SECRET_INTERVAL,
.procname = "ipfrag_secret_interval",
Expand Down Expand Up @@ -658,8 +662,6 @@ static int ip4_frags_ns_ctl_register(struct net *net)
table[0].data = &net->ipv4.frags.high_thresh;
table[1].data = &net->ipv4.frags.low_thresh;
table[2].data = &net->ipv4.frags.timeout;
table[3].mode &= ~0222;
table[4].mode &= ~0222;
}

hdr = register_net_sysctl_table(net, net_ipv4_ctl_path, table);
Expand All @@ -684,6 +686,11 @@ static void ip4_frags_ns_ctl_unregister(struct net *net)
unregister_net_sysctl_table(net->ipv4.frags_hdr);
kfree(table);
}

static void ip4_frags_ctl_register(void)
{
register_net_sysctl_rotable(net_ipv4_ctl_path, ip4_frags_ctl_table);
}
#else
static inline int ip4_frags_ns_ctl_register(struct net *net)
{
Expand All @@ -693,6 +700,10 @@ static inline int ip4_frags_ns_ctl_register(struct net *net)
static inline void ip4_frags_ns_ctl_unregister(struct net *net)
{
}

static inline void ip4_frags_ctl_register(void)
{
}
#endif

static int ipv4_frags_init_net(struct net *net)
Expand Down Expand Up @@ -730,6 +741,7 @@ static struct pernet_operations ip4_frags_ops = {

void __init ipfrag_init(void)
{
ip4_frags_ctl_register();
register_pernet_subsys(&ip4_frags_ops);
ip4_frags.hashfn = ip4_hashfn;
ip4_frags.constructor = ip4_frag_init;
Expand Down
35 changes: 34 additions & 1 deletion net/ipv6/reassembly.c
Original file line number Diff line number Diff line change
Expand Up @@ -658,6 +658,10 @@ static struct ctl_table ip6_frags_ns_ctl_table[] = {
.proc_handler = &proc_dointvec_jiffies,
.strategy = &sysctl_jiffies,
},
{ }
};

static struct ctl_table ip6_frags_ctl_table[] = {
{
.ctl_name = NET_IPV6_IP6FRAG_SECRET_INTERVAL,
.procname = "ip6frag_secret_interval",
Expand All @@ -684,7 +688,6 @@ static int ip6_frags_ns_sysctl_register(struct net *net)
table[0].data = &net->ipv6.frags.high_thresh;
table[1].data = &net->ipv6.frags.low_thresh;
table[2].data = &net->ipv6.frags.timeout;
table[3].mode &= ~0222;
}

hdr = register_net_sysctl_table(net, net_ipv6_ctl_path, table);
Expand All @@ -709,6 +712,20 @@ static void ip6_frags_ns_sysctl_unregister(struct net *net)
unregister_net_sysctl_table(net->ipv6.sysctl.frags_hdr);
kfree(table);
}

static struct ctl_table_header *ip6_ctl_header;

static int ip6_frags_sysctl_register(void)
{
ip6_ctl_header = register_net_sysctl_rotable(net_ipv6_ctl_path,
ip6_frags_ctl_table);
return ip6_ctl_header == NULL ? -ENOMEM : 0;
}

static void ip6_frags_sysctl_unregister(void)
{
unregister_net_sysctl_table(ip6_ctl_header);
}
#else
static inline int ip6_frags_ns_sysctl_register(struct net *net)
{
Expand All @@ -718,6 +735,15 @@ static inline int ip6_frags_ns_sysctl_register(struct net *net)
static inline void ip6_frags_ns_sysctl_unregister(struct net *net)
{
}

static inline int ip6_frags_sysctl_register(void)
{
return 0;
}

static inline void ip6_frags_sysctl_unregister(void)
{
}
#endif

static int ipv6_frags_init_net(struct net *net)
Expand Down Expand Up @@ -750,6 +776,10 @@ int __init ipv6_frag_init(void)
if (ret)
goto out;

ret = ip6_frags_sysctl_register();
if (ret)
goto err_sysctl;

ret = register_pernet_subsys(&ip6_frags_ops);
if (ret)
goto err_pernet;
Expand All @@ -767,13 +797,16 @@ int __init ipv6_frag_init(void)
return ret;

err_pernet:
ip6_frags_sysctl_unregister();
err_sysctl:
inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT);
goto out;
}

void ipv6_frag_exit(void)
{
inet_frags_fini(&ip6_frags);
ip6_frags_sysctl_unregister();
unregister_pernet_subsys(&ip6_frags_ops);
inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT);
}

0 comments on commit 7d291eb

Please sign in to comment.