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| author |   Jason A. Donenfeld <Jason@zx2c4.com> | 2016-12-16 06:56:39 +0100 |
|---|---|---|
| committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2016-12-16 06:56:39 +0100 |
| commit | 2b542fa8d05f465930532e58cc128496f9a53505 (patch) | |
| tree | 3bc29fdacf87d3a34440496a4147177f1c70b05b /src/hashtables.c | |
| parent | messages: increase header by 3 bytes for alignment (diff) | |
| download | wireguard-monolithic-historical-2b542fa8d05f465930532e58cc128496f9a53505.tar.xz wireguard-monolithic-historical-2b542fa8d05f465930532e58cc128496f9a53505.zip | |
hashtables: use counter and int to ensure forward progress
Diffstat (limited to 'src/hashtables.c')
| -rw-r--r-- | src/hashtables.c | 11 |
1 files changed, 2 insertions, 9 deletions
diff --git a/src/hashtables.c b/src/hashtables.c index 45c9737..534ad55 100644 --- a/src/hashtables.c +++ b/src/hashtables.c @@ -65,16 +65,10 @@ void index_hashtable_init(struct index_hashtable *table) spin_lock_init(&table->lock); } -#if BITS_PER_LONG == 64 -#define get_random_u64() get_random_long() -#else -#define get_random_u64() (((u64)get_random_int() << 32) | get_random_int()) -#endif - __le32 index_hashtable_insert(struct index_hashtable *table, struct index_hashtable_entry *entry) { struct index_hashtable_entry *existing_entry; - u64 rand; + u32 counter = get_random_int(); spin_lock(&table->lock); hlist_del_init_rcu(&entry->index_hash); @@ -84,8 +78,7 @@ __le32 index_hashtable_insert(struct index_hashtable *table, struct index_hashta search_unused_slot: /* First we try to find an unused slot, randomly, while unlocked. */ - rand = get_random_u64(); - entry->index = (__force __le32)siphash_1u64(rand, table->key); + entry->index = (__force __le32)siphash_2u32(get_random_int(), counter++, table->key); hlist_for_each_entry_rcu(existing_entry, index_bucket(table, entry->index), index_hash) { if (existing_entry->index == entry->index) goto search_unused_slot; /* If it's already in use, we continue searching. */ |