kernel/include/net/request_sock.h, branch linux-4.14.y

net: add {READ|WRITE}_ONCE() annotations on ->rskq_accept_head

2020-01-27T13:46:50Z

[ Upstream commit 60b173ca3d1cd1782bd0096dc17298ec242f6fb1 ] reqsk_queue_empty() is called from inet_csk_listen_poll() while other cpus might write ->rskq_accept_head value. Use {READ|WRITE}_ONCE() to avoid compiler tricks and potential KCSAN splats. Fixes: fff1f3001cc5 ("tcp: add a spinlock to protect struct request_sock_queue") Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: convert sock.sk_refcnt from atomic_t to refcount_t

2017-07-01T14:39:08Z

refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. This patch uses refcount_inc_not_zero() instead of atomic_inc_not_zero_hint() due to absense of a _hint() version of refcount API. If the hint() version must be used, we might need to revisit API. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller

net: make struct request_sock_ops::obj_size unsigned

2017-05-23T15:13:19Z

This field is sizeof of corresponding kmem_cache so it can't be negative. Space will be saved after 32-bit kmem_cache_create() patch. Signed-off-by: Alexey Dobriyan Signed-off-by: David S. Miller

ipv4: Namespaceify tcp_max_syn_backlog knob

2016-12-29T16:38:31Z

Different namespace application might require different maximal number of remembered connection requests. Signed-off-by: Haishuang Yan Signed-off-by: David S. Miller

inet: reqsk_alloc() needs to take care of dead listeners

2016-04-05T02:11:19Z

We'll soon no longer take a refcount on listeners, so reqsk_alloc() can not assume a listener refcount is not zero. We need to use atomic_inc_not_zero() Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net: add inet_sk_transparent() helper

2015-12-22T22:03:05Z

Avoids cluttering tcp_v4_send_reset when followup patch extends it to deal with timewait sockets. Suggested-by: Eric Dumazet Signed-off-by: Florian Westphal Acked-by: Eric Dumazet Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

tcp/dccp: fix race at listener dismantle phase

2015-10-16T07:52:19Z

Under stress, a close() on a listener can trigger the WARN_ON(sk->sk_ack_backlog) in inet_csk_listen_stop() We need to test if listener is still active before queueing a child in inet_csk_reqsk_queue_add() Create a common inet_child_forget() helper, and use it from inet_csk_reqsk_queue_add() and inet_csk_listen_stop() Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net: shrink struct sock and request_sock by 8 bytes

2015-10-13T02:28:22Z

One 32bit hole is following skc_refcnt, use it. skc_incoming_cpu can also be an union for request_sock rcv_wnd. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net: align sk_refcnt on 128 bytes boundary

2015-10-13T02:28:22Z

sk->sk_refcnt is dirtied for every TCP/UDP incoming packet. This is a performance issue if multiple cpus hit a common socket, or multiple sockets are chained due to SO_REUSEPORT. By moving sk_refcnt 8 bytes further, first 128 bytes of sockets are mostly read. As they contain the lookup keys, this has a considerable performance impact, as cpus can cache them. These 8 bytes are not wasted, we use them as a place holder for various fields, depending on the socket type. Tested: SYN flood hitting a 16 RX queues NIC. TCP listener using 16 sockets and SO_REUSEPORT and SO_INCOMING_CPU for proper siloing. Could process 6.0 Mpps SYN instead of 4.2 Mpps Kernel profile looked like : 11.68% [kernel] [k] sha_transform 6.51% [kernel] [k] __inet_lookup_listener 5.07% [kernel] [k] __inet_lookup_established 4.15% [kernel] [k] memcpy_erms 3.46% [kernel] [k] ipt_do_table 2.74% [kernel] [k] fib_table_lookup 2.54% [kernel] [k] tcp_make_synack 2.34% [kernel] [k] tcp_conn_request 2.05% [kernel] [k] __netif_receive_skb_core 2.03% [kernel] [k] kmem_cache_alloc Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: avoid two atomic ops for syncookies

2015-10-05T09:45:27Z

inet_reqsk_alloc() is used to allocate a temporary request in order to generate a SYNACK with a cookie. Then later, syncookie validation also uses a temporary request. These paths already took a reference on listener refcount, we can avoid a couple of atomic operations. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller