udp: udp_lib_get_port() fix

Now we can have a large udp hash table, udp_lib_get_port() loop
should be converted to a do {} while (cond) form,
or we dont enter it at all if hash table size is exactly 65536.

Reported-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2009-12-13 19:32:39 -08:00 committed by David S. Miller
parent e1187b3be7
commit 5781b2356c

View file

@ -216,9 +216,8 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
* force rand to be an odd multiple of UDP_HTABLE_SIZE
*/
rand = (rand | 1) * (udptable->mask + 1);
for (last = first + udptable->mask + 1;
first != last;
first++) {
last = first + udptable->mask + 1;
do {
hslot = udp_hashslot(udptable, net, first);
bitmap_zero(bitmap, PORTS_PER_CHAIN);
spin_lock_bh(&hslot->lock);
@ -238,7 +237,7 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
snum += rand;
} while (snum != first);
spin_unlock_bh(&hslot->lock);
}
} while (++first != last);
goto fail;
} else {
hslot = udp_hashslot(udptable, net, snum);