From: Willy Tarreau <w@xxxxxx> commit 9e9b70ae923baf2b5e8a0ea4fd0c8451801ac526 upstream. Amit Klein suggests that we use different parts of port_offset for the table's index and the port offset so that there is no direct relation between them. Cc: Jason A. Donenfeld <Jason@xxxxxxxxx> Cc: Moshe Kol <moshe.kol@xxxxxxxxxxxxxxx> Cc: Yossi Gilad <yossi.gilad@xxxxxxxxxxxxxxx> Cc: Amit Klein <aksecurity@xxxxxxxxx> Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx> Signed-off-by: Willy Tarreau <w@xxxxxx> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Cc: Ben Hutchings <ben@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/inet_hashtables.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -777,7 +777,7 @@ int __inet_hash_connect(struct inet_time net_get_random_once(table_perturb, sizeof(table_perturb)); index = hash_32(port_offset, INET_TABLE_PERTURB_SHIFT); - offset = READ_ONCE(table_perturb[index]) + port_offset; + offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32); offset %= remaining; /* In first pass we try ports of @low parity.
