summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--net/ipv4/udp.c56
1 files changed, 12 insertions, 44 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 85f8e8e10b1b..67d8430b4a2a 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -155,55 +155,23 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
write_lock_bh(&udp_hash_lock);
if (!snum) {
- int i, low, high, remaining;
- unsigned rover, best, best_size_so_far;
+ int low, high, remaining;
+ unsigned rand;
+ unsigned short first;
inet_get_local_port_range(&low, &high);
remaining = (high - low) + 1;
- best_size_so_far = UINT_MAX;
- best = rover = net_random() % remaining + low;
-
- /* 1st pass: look for empty (or shortest) hash chain */
- for (i = 0; i < UDP_HTABLE_SIZE; i++) {
- int size = 0;
-
- head = &udptable[udp_hashfn(net, rover)];
- if (hlist_empty(head))
- goto gotit;
-
- sk_for_each(sk2, node, head) {
- if (++size >= best_size_so_far)
- goto next;
- }
- best_size_so_far = size;
- best = rover;
- next:
- /* fold back if end of range */
- if (++rover > high)
- rover = low + ((rover - low)
- & (UDP_HTABLE_SIZE - 1));
-
-
- }
-
- /* 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(net, rover, udptable))
- goto gotit;
- rover += UDP_HTABLE_SIZE;
- if (rover > high)
- rover = low + ((rover - low)
- & (UDP_HTABLE_SIZE - 1));
+ rand = net_random();
+ snum = first = rand % remaining + low;
+ rand |= 1;
+ while (__udp_lib_lport_inuse(net, snum, udptable)) {
+ do {
+ snum = snum + rand;
+ } while (snum < low || snum > high);
+ if (snum == first)
+ goto fail;
}
-
-
- /* All ports in use! */
- goto fail;
-
-gotit:
- snum = rover;
} else {
head = &udptable[udp_hashfn(net, snum)];