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| author | Willy Tarreau <w@1wt.eu> | 2022-05-02 10:46:12 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-05-18 10:26:53 +0200 |
| commit | 4a3eefa399e675c4a5239497832a72733281a20f (patch) | |
| tree | 3fb8be11738a9a0fd8460d580a4ead7849b3e11f /net | |
| parent | b763fce193b42048444afd85d066b136288ad2c8 (diff) | |
| download | linux-4a3eefa399e675c4a5239497832a72733281a20f.tar.gz linux-4a3eefa399e675c4a5239497832a72733281a20f.tar.bz2 linux-4a3eefa399e675c4a5239497832a72733281a20f.zip | |
tcp: dynamically allocate the perturb table used by source ports
[ Upstream commit e9261476184be1abd486c9434164b2acbe0ed6c2 ]
We'll need to further increase the size of this table and it's likely
that at some point its size will not be suitable anymore for a static
table. Let's allocate it on boot from inet_hashinfo2_init(), which is
called from tcp_init().
Cc: Moshe Kol <moshe.kol@mail.huji.ac.il>
Cc: Yossi Gilad <yossi.gilad@mail.huji.ac.il>
Cc: Amit Klein <aksecurity@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/inet_hashtables.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index 573a7e66ebc8..763395e30c77 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -731,7 +731,8 @@ EXPORT_SYMBOL_GPL(inet_unhash); * privacy, this only consumes 1 KB of kernel memory. */ #define INET_TABLE_PERTURB_SHIFT 8 -static u32 table_perturb[1 << INET_TABLE_PERTURB_SHIFT]; +#define INET_TABLE_PERTURB_SIZE (1 << INET_TABLE_PERTURB_SHIFT) +static u32 *table_perturb; int __inet_hash_connect(struct inet_timewait_death_row *death_row, struct sock *sk, u64 port_offset, @@ -774,7 +775,8 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, if (likely(remaining > 1)) remaining &= ~1U; - net_get_random_once(table_perturb, sizeof(table_perturb)); + net_get_random_once(table_perturb, + INET_TABLE_PERTURB_SIZE * sizeof(*table_perturb)); index = hash_32(port_offset, INET_TABLE_PERTURB_SHIFT); offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32); @@ -912,6 +914,12 @@ void __init inet_hashinfo2_init(struct inet_hashinfo *h, const char *name, low_limit, high_limit); init_hashinfo_lhash2(h); + + /* this one is used for source ports of outgoing connections */ + table_perturb = kmalloc_array(INET_TABLE_PERTURB_SIZE, + sizeof(*table_perturb), GFP_KERNEL); + if (!table_perturb) + panic("TCP: failed to alloc table_perturb"); } int inet_hashinfo2_init_mod(struct inet_hashinfo *h) |