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Diffstat (limited to 'net/ipv4/udp.c')
-rw-r--r--net/ipv4/udp.c89
1 files changed, 48 insertions, 41 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 69d4bd10f9c6..cb9fc58efb2f 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -98,6 +98,7 @@
#include <linux/skbuff.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
+#include <net/net_namespace.h>
#include <net/icmp.h>
#include <net/route.h>
#include <net/checksum.h>
@@ -113,9 +114,8 @@ DEFINE_SNMP_STAT(struct udp_mib, udp_statistics) __read_mostly;
struct hlist_head udp_hash[UDP_HTABLE_SIZE];
DEFINE_RWLOCK(udp_hash_lock);
-static int udp_port_rover;
-
-static inline int __udp_lib_lport_inuse(__u16 num, struct hlist_head udptable[])
+static inline int __udp_lib_lport_inuse(__u16 num,
+ const struct hlist_head udptable[])
{
struct sock *sk;
struct hlist_node *node;
@@ -132,11 +132,10 @@ static inline int __udp_lib_lport_inuse(__u16 num, struct hlist_head udptable[])
* @sk: socket struct in question
* @snum: port number to look up
* @udptable: hash list table, must be of UDP_HTABLE_SIZE
- * @port_rover: pointer to record of last unallocated port
* @saddr_comp: AF-dependent comparison of bound local IP addresses
*/
int __udp_lib_get_port(struct sock *sk, unsigned short snum,
- struct hlist_head udptable[], int *port_rover,
+ struct hlist_head udptable[],
int (*saddr_comp)(const struct sock *sk1,
const struct sock *sk2 ) )
{
@@ -146,49 +145,56 @@ int __udp_lib_get_port(struct sock *sk, unsigned short snum,
int error = 1;
write_lock_bh(&udp_hash_lock);
- if (snum == 0) {
- int best_size_so_far, best, result, i;
-
- if (*port_rover > sysctl_local_port_range[1] ||
- *port_rover < sysctl_local_port_range[0])
- *port_rover = sysctl_local_port_range[0];
- best_size_so_far = 32767;
- best = result = *port_rover;
- for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) {
- int size;
-
- head = &udptable[result & (UDP_HTABLE_SIZE - 1)];
- if (hlist_empty(head)) {
- if (result > sysctl_local_port_range[1])
- result = sysctl_local_port_range[0] +
- ((result - sysctl_local_port_range[0]) &
- (UDP_HTABLE_SIZE - 1));
+
+ if (!snum) {
+ int i, low, high;
+ unsigned rover, best, best_size_so_far;
+
+ inet_get_local_port_range(&low, &high);
+
+ best_size_so_far = UINT_MAX;
+ best = rover = net_random() % (high - low) + low;
+
+ /* 1st pass: look for empty (or shortest) hash chain */
+ for (i = 0; i < UDP_HTABLE_SIZE; i++) {
+ int size = 0;
+
+ head = &udptable[rover & (UDP_HTABLE_SIZE - 1)];
+ if (hlist_empty(head))
goto gotit;
- }
- size = 0;
+
sk_for_each(sk2, node, head) {
if (++size >= best_size_so_far)
goto next;
}
best_size_so_far = size;
- best = result;
+ best = rover;
next:
- ;
+ /* fold back if end of range */
+ if (++rover > high)
+ rover = low + ((rover - low)
+ & (UDP_HTABLE_SIZE - 1));
+
+
}
- result = best;
- for (i = 0; i < (1 << 16) / UDP_HTABLE_SIZE;
- i++, result += UDP_HTABLE_SIZE) {
- if (result > sysctl_local_port_range[1])
- result = sysctl_local_port_range[0]
- + ((result - sysctl_local_port_range[0]) &
- (UDP_HTABLE_SIZE - 1));
- if (! __udp_lib_lport_inuse(result, udptable))
- break;
+
+ /* 2nd pass: find hole in shortest hash chain */
+ rover = best;
+ for (i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; i++) {
+ if (! __udp_lib_lport_inuse(rover, udptable))
+ goto gotit;
+ rover += UDP_HTABLE_SIZE;
+ if (rover > high)
+ rover = low + ((rover - low)
+ & (UDP_HTABLE_SIZE - 1));
}
- if (i >= (1 << 16) / UDP_HTABLE_SIZE)
- goto fail;
+
+
+ /* All ports in use! */
+ goto fail;
+
gotit:
- *port_rover = snum = result;
+ snum = rover;
} else {
head = &udptable[snum & (UDP_HTABLE_SIZE - 1)];
@@ -201,6 +207,7 @@ gotit:
(*saddr_comp)(sk, sk2) )
goto fail;
}
+
inet_sk(sk)->num = snum;
sk->sk_hash = snum;
if (sk_unhashed(sk)) {
@@ -217,7 +224,7 @@ fail:
int udp_get_port(struct sock *sk, unsigned short snum,
int (*scmp)(const struct sock *, const struct sock *))
{
- return __udp_lib_get_port(sk, snum, udp_hash, &udp_port_rover, scmp);
+ return __udp_lib_get_port(sk, snum, udp_hash, scmp);
}
int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2)
@@ -1560,7 +1567,7 @@ int udp_proc_register(struct udp_seq_afinfo *afinfo)
afinfo->seq_fops->llseek = seq_lseek;
afinfo->seq_fops->release = seq_release_private;
- p = proc_net_fops_create(afinfo->name, S_IRUGO, afinfo->seq_fops);
+ p = proc_net_fops_create(&init_net, afinfo->name, S_IRUGO, afinfo->seq_fops);
if (p)
p->data = afinfo;
else
@@ -1572,7 +1579,7 @@ void udp_proc_unregister(struct udp_seq_afinfo *afinfo)
{
if (!afinfo)
return;
- proc_net_remove(afinfo->name);
+ proc_net_remove(&init_net, afinfo->name);
memset(afinfo->seq_fops, 0, sizeof(*afinfo->seq_fops));
}