net: change proto and proto_ops accept type

Rather than pass in flags, error pointer, and whether this is a kernel
invocation or not, add a struct proto_accept_arg struct as the argument.
This then

net: change proto and proto_ops accept type

Rather than pass in flags, error pointer, and whether this is a kernel
invocation or not, add a struct proto_accept_arg struct as the argument.
This then holds all of these arguments, and prepares accept for being
able to pass back more information.

No functional changes in this patch.

Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

net: move sysctl_mem_pcpu_rsv to net_hotdata

sysctl_mem_pcpu_rsv is used in TCP fast path,
move it to net_hodata for better cache locality.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewe

net: move sysctl_mem_pcpu_rsv to net_hotdata

sysctl_mem_pcpu_rsv is used in TCP fast path,
move it to net_hodata for better cache locality.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240429134025.1233626-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: add <net/proto_memory.h>

Move some proto memory definitions out of <net/sock.h>

Very few files need them, and following patch
will include <net/hotdata.h> from <net/proto_memory.h>

Signed-off

net: add <net/proto_memory.h>

Move some proto memory definitions out of <net/sock.h>

Very few files need them, and following patch
will include <net/hotdata.h> from <net/proto_memory.h>

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240429134025.1233626-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: skbuff: generalize the skb->decrypted bit

The ->decrypted bit can be reused for other crypto protocols.
Remove the direct dependency on TLS, add helpers to clean up
the ifdefs leaking out every

net: skbuff: generalize the skb->decrypted bit

The ->decrypted bit can be reused for other crypto protocols.
Remove the direct dependency on TLS, add helpers to clean up
the ifdefs leaking out everywhere.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: add sk_wake_async_rcu() helper

While looking at UDP receive performance, I saw sk_wake_async()
was no longer inlined.

This matters at least on AMD Zen1-4 platforms (see SRSO)

This might be be

net: add sk_wake_async_rcu() helper

While looking at UDP receive performance, I saw sk_wake_async()
was no longer inlined.

This matters at least on AMD Zen1-4 platforms (see SRSO)

This might be because rcu_read_lock() and rcu_read_unlock()
are no longer nops in recent kernels ?

Add sk_wake_async_rcu() variant, which must be called from
contexts already holding rcu lock.

As SOCK_FASYNC is deprecated in modern days, use unlikely()
to give a hint to the compiler.

sk_wake_async_rcu() is properly inlined from
__udp_enqueue_schedule_skb() and sock_def_readable().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240328144032.1864988-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: mark racy access on sk->sk_rcvbuf

sk->sk_rcvbuf in __sock_queue_rcv_skb() and __sk_receive_skb() can be
changed by other threads. Mark this as benign using READ_ONCE().

This patch is aimed at

net: mark racy access on sk->sk_rcvbuf

sk->sk_rcvbuf in __sock_queue_rcv_skb() and __sk_receive_skb() can be
changed by other threads. Mark this as benign using READ_ONCE().

This patch is aimed at reducing the number of benign races reported by
KCSAN in order to focus future debugging effort on harmful races.

Signed-off-by: linke li <lilinke99@qq.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

sock: Use unsafe_memcpy() for sock_copy()

While testing for places where zero-sized destinations were still showing
up in the kernel, sock_copy() and inet_reqsk_clone() were found, which
are using v

sock: Use unsafe_memcpy() for sock_copy()

While testing for places where zero-sized destinations were still showing
up in the kernel, sock_copy() and inet_reqsk_clone() were found, which
are using very specific memcpy() offsets for both avoiding a portion of
struct sock, and copying beyond the end of it (since struct sock is really
just a common header before the protocol-specific allocation). Instead
of trying to unravel this historical lack of container_of(), just switch
to unsafe_memcpy(), since that's effectively what was happening already
(memcpy() wasn't checking 0-sized destinations while the code base was
being converted away from fake flexible arrays).

Avoid the following false positive warning with future changes to
CONFIG_FORTIFY_SOURCE:

memcpy: detected field-spanning write (size 3068) of destination "&nsk->__sk_common.skc_dontcopy_end" at net/core/sock.c:2057 (size 0)

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240304212928.make.772-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

net: make SK_MEMORY_PCPU_RESERV tunable

This patch adds /proc/sys/net/core/mem_pcpu_rsv sysctl file,
to make SK_MEMORY_PCPU_RESERV tunable.

Commit 3cd3399dd7a8 ("net: implement per-cpu reserves for

net: make SK_MEMORY_PCPU_RESERV tunable

This patch adds /proc/sys/net/core/mem_pcpu_rsv sysctl file,
to make SK_MEMORY_PCPU_RESERV tunable.

Commit 3cd3399dd7a8 ("net: implement per-cpu reserves for
memory_allocated") introduced per-cpu forward alloc cache:

"Implement a per-cpu cache of +1/-1 MB, to reduce number
of changes to sk->sk_prot->memory_allocated, which
would otherwise be cause of false sharing."

sk_prot->memory_allocated points to global atomic variable:
atomic_long_t tcp_memory_allocated ____cacheline_aligned_in_smp;

If increasing the per-cpu cache size from 1MB to e.g. 16MB,
changes to sk->sk_prot->memory_allocated can be further reduced.
Performance may be improved on system with many cores.

Signed-off-by: Adam Li <adamli@os.amperecomputing.com>
Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: implement lockless setsockopt(SO_PEEK_OFF)

syzbot reported a lockdep violation [1] involving af_unix
support of SO_PEEK_OFF.

Since SO_PEEK_OFF is inherently not thread safe (it uses a per-sock

net: implement lockless setsockopt(SO_PEEK_OFF)

syzbot reported a lockdep violation [1] involving af_unix
support of SO_PEEK_OFF.

Since SO_PEEK_OFF is inherently not thread safe (it uses a per-socket
sk_peek_off field), there is really no point to enforce a pointless
thread safety in the kernel.

After this patch :

- setsockopt(SO_PEEK_OFF) no longer acquires the socket lock.

- skb_consume_udp() no longer has to acquire the socket lock.

- af_unix no longer needs a special version of sk_set_peek_off(),
because it does not lock u->iolock anymore.

As a followup, we could replace prot->set_peek_off to be a boolean
and avoid an indirect call, since we always use sk_set_peek_off().

[1]

WARNING: possible circular locking dependency detected
6.8.0-rc4-syzkaller-00267-g0f1dd5e91e2b #0 Not tainted

syz-executor.2/30025 is trying to acquire lock:
ffff8880765e7d80 (&u->iolock){+.+.}-{3:3}, at: unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789

but task is already holding lock:
ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline]
ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1060 [inline]
ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sk_setsockopt+0xe52/0x3360 net/core/sock.c:1193

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (sk_lock-AF_UNIX){+.+.}-{0:0}:
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
lock_sock_nested+0x48/0x100 net/core/sock.c:3524
lock_sock include/net/sock.h:1691 [inline]
__unix_dgram_recvmsg+0x1275/0x12c0 net/unix/af_unix.c:2415
sock_recvmsg_nosec+0x18e/0x1d0 net/socket.c:1046
____sys_recvmsg+0x3c0/0x470 net/socket.c:2801
___sys_recvmsg net/socket.c:2845 [inline]
do_recvmmsg+0x474/0xae0 net/socket.c:2939
__sys_recvmmsg net/socket.c:3018 [inline]
__do_sys_recvmmsg net/socket.c:3041 [inline]
__se_sys_recvmmsg net/socket.c:3034 [inline]
__x64_sys_recvmmsg+0x199/0x250 net/socket.c:3034
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77

-> #0 (&u->iolock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869
__lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789
sk_setsockopt+0x207e/0x3360
do_sock_setsockopt+0x2fb/0x720 net/socket.c:2307
__sys_setsockopt+0x1ad/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(sk_lock-AF_UNIX);
lock(&u->iolock);
lock(sk_lock-AF_UNIX);
lock(&u->iolock);

*** DEADLOCK ***

1 lock held by syz-executor.2/30025:
#0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline]
#0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1060 [inline]
#0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sk_setsockopt+0xe52/0x3360 net/core/sock.c:1193

stack backtrace:
CPU: 0 PID: 30025 Comm: syz-executor.2 Not tainted 6.8.0-rc4-syzkaller-00267-g0f1dd5e91e2b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869
__lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789
sk_setsockopt+0x207e/0x3360
do_sock_setsockopt+0x2fb/0x720 net/socket.c:2307
__sys_setsockopt+0x1ad/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f78a1c7dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f78a0fde0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f78a1dac050 RCX: 00007f78a1c7dda9
RDX: 000000000000002a RSI: 0000000000000001 RDI: 0000000000000006
RBP: 00007f78a1cca47a R08: 0000000000000004 R09: 0000000000000000
R10: 0000000020000180 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f78a1dac050 R15: 00007ffe5cd81ae8

Fixes: 859051dd165e ("bpf: Implement cgroup sockaddr hooks for unix sockets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: Daan De Meyer <daan.j.demeyer@gmail.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: Martin KaFai Lau <martin.lau@kernel.org>
Cc: David Ahern <dsahern@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

net: reorganize "struct sock" fields

Last major reorg happened in commit 9115e8cd2a0c ("net: reorganize
struct sock for better data locality")

Since then, many changes have been done.

Before SO_PE

net: reorganize "struct sock" fields

Last major reorg happened in commit 9115e8cd2a0c ("net: reorganize
struct sock for better data locality")

Since then, many changes have been done.

Before SO_PEEK_OFF support is added to TCP, we need
to move sk_peek_off to a better location.

It is time to make another pass, and add six groups,
without explicit alignment.

- sock_write_rx (following sk_refcnt) read-write fields in rx path.
- sock_read_rx read-mostly fields in rx path.
- sock_read_rxtx read-mostly fields in both rx and tx paths.
- sock_write_rxtx read-write fields in both rx and tx paths.
- sock_write_tx read-write fields in tx paths.
- sock_read_tx read-mostly fields in tx paths.

Results on TCP_RR benchmarks seem to show a gain (4 to 5 %).

It is possible UDP needs a change, because sk_peek_off
shares a cache line with sk_receive_queue.
If this the case, we can exchange roles of sk->sk_receive
and up->reader_queue queues.

After this change, we have the following layout:

struct sock {
struct sock_common __sk_common; /* 0 0x88 */
/* --- cacheline 2 boundary (128 bytes) was 8 bytes ago --- */
__u8 __cacheline_group_begin__sock_write_rx[0]; /* 0x88 0 */
atomic_t sk_drops; /* 0x88 0x4 */
__s32 sk_peek_off; /* 0x8c 0x4 */
struct sk_buff_head sk_error_queue; /* 0x90 0x18 */
struct sk_buff_head sk_receive_queue; /* 0xa8 0x18 */
/* --- cacheline 3 boundary (192 bytes) --- */
struct {
atomic_t rmem_alloc; /* 0xc0 0x4 */
int len; /* 0xc4 0x4 */
struct sk_buff * head; /* 0xc8 0x8 */
struct sk_buff * tail; /* 0xd0 0x8 */
} sk_backlog; /* 0xc0 0x18 */
struct {
atomic_t rmem_alloc; /* 0 0x4 */
int len; /* 0x4 0x4 */
struct sk_buff * head; /* 0x8 0x8 */
struct sk_buff * tail; /* 0x10 0x8 */

/* size: 24, cachelines: 1, members: 4 */
/* last cacheline: 24 bytes */
};

__u8 __cacheline_group_end__sock_write_rx[0]; /* 0xd8 0 */
__u8 __cacheline_group_begin__sock_read_rx[0]; /* 0xd8 0 */
rcu * sk_rx_dst; /* 0xd8 0x8 */
int sk_rx_dst_ifindex; /* 0xe0 0x4 */
u32 sk_rx_dst_cookie; /* 0xe4 0x4 */
unsigned int sk_ll_usec; /* 0xe8 0x4 */
unsigned int sk_napi_id; /* 0xec 0x4 */
u16 sk_busy_poll_budget; /* 0xf0 0x2 */
u8 sk_prefer_busy_poll; /* 0xf2 0x1 */
u8 sk_userlocks; /* 0xf3 0x1 */
int sk_rcvbuf; /* 0xf4 0x4 */
rcu * sk_filter; /* 0xf8 0x8 */
/* --- cacheline 4 boundary (256 bytes) --- */
union {
rcu * sk_wq; /* 0x100 0x8 */
struct socket_wq * sk_wq_raw; /* 0x100 0x8 */
}; /* 0x100 0x8 */
union {
rcu * sk_wq; /* 0 0x8 */
struct socket_wq * sk_wq_raw; /* 0 0x8 */
};

void (*sk_data_ready)(struct sock *); /* 0x108 0x8 */
long sk_rcvtimeo; /* 0x110 0x8 */
int sk_rcvlowat; /* 0x118 0x4 */
__u8 __cacheline_group_end__sock_read_rx[0]; /* 0x11c 0 */
__u8 __cacheline_group_begin__sock_read_rxtx[0]; /* 0x11c 0 */
int sk_err; /* 0x11c 0x4 */
struct socket * sk_socket; /* 0x120 0x8 */
struct mem_cgroup * sk_memcg; /* 0x128 0x8 */
rcu * sk_policy[2]; /* 0x130 0x10 */
/* --- cacheline 5 boundary (320 bytes) --- */
__u8 __cacheline_group_end__sock_read_rxtx[0]; /* 0x140 0 */
__u8 __cacheline_group_begin__sock_write_rxtx[0]; /* 0x140 0 */
socket_lock_t sk_lock; /* 0x140 0x20 */
u32 sk_reserved_mem; /* 0x160 0x4 */
int sk_forward_alloc; /* 0x164 0x4 */
u32 sk_tsflags; /* 0x168 0x4 */
__u8 __cacheline_group_end__sock_write_rxtx[0]; /* 0x16c 0 */
__u8 __cacheline_group_begin__sock_write_tx[0]; /* 0x16c 0 */
int sk_write_pending; /* 0x16c 0x4 */
atomic_t sk_omem_alloc; /* 0x170 0x4 */
int sk_sndbuf; /* 0x174 0x4 */
int sk_wmem_queued; /* 0x178 0x4 */
refcount_t sk_wmem_alloc; /* 0x17c 0x4 */
/* --- cacheline 6 boundary (384 bytes) --- */
unsigned long sk_tsq_flags; /* 0x180 0x8 */
union {
struct sk_buff * sk_send_head; /* 0x188 0x8 */
struct rb_root tcp_rtx_queue; /* 0x188 0x8 */
}; /* 0x188 0x8 */
union {
struct sk_buff * sk_send_head; /* 0 0x8 */
struct rb_root tcp_rtx_queue; /* 0 0x8 */
};

struct sk_buff_head sk_write_queue; /* 0x190 0x18 */
u32 sk_dst_pending_confirm; /* 0x1a8 0x4 */
u32 sk_pacing_status; /* 0x1ac 0x4 */
struct page_frag sk_frag; /* 0x1b0 0x10 */
/* --- cacheline 7 boundary (448 bytes) --- */
struct timer_list sk_timer; /* 0x1c0 0x28 */

/* XXX last struct has 4 bytes of padding */

unsigned long sk_pacing_rate; /* 0x1e8 0x8 */
atomic_t sk_zckey; /* 0x1f0 0x4 */
atomic_t sk_tskey; /* 0x1f4 0x4 */
__u8 __cacheline_group_end__sock_write_tx[0]; /* 0x1f8 0 */
__u8 __cacheline_group_begin__sock_read_tx[0]; /* 0x1f8 0 */
unsigned long sk_max_pacing_rate; /* 0x1f8 0x8 */
/* --- cacheline 8 boundary (512 bytes) --- */
long sk_sndtimeo; /* 0x200 0x8 */
u32 sk_priority; /* 0x208 0x4 */
u32 sk_mark; /* 0x20c 0x4 */
rcu * sk_dst_cache; /* 0x210 0x8 */
netdev_features_t sk_route_caps; /* 0x218 0x8 */
u16 sk_gso_type; /* 0x220 0x2 */
u16 sk_gso_max_segs; /* 0x222 0x2 */
unsigned int sk_gso_max_size; /* 0x224 0x4 */
gfp_t sk_allocation; /* 0x228 0x4 */
u32 sk_txhash; /* 0x22c 0x4 */
u8 sk_pacing_shift; /* 0x230 0x1 */
bool sk_use_task_frag; /* 0x231 0x1 */
__u8 __cacheline_group_end__sock_read_tx[0]; /* 0x232 0 */
u8 sk_gso_disabled:1; /* 0x232: 0 0x1 */
u8 sk_kern_sock:1; /* 0x232:0x1 0x1 */
u8 sk_no_check_tx:1; /* 0x232:0x2 0x1 */
u8 sk_no_check_rx:1; /* 0x232:0x3 0x1 */

/* XXX 4 bits hole, try to pack */

u8 sk_shutdown; /* 0x233 0x1 */
u16 sk_type; /* 0x234 0x2 */
u16 sk_protocol; /* 0x236 0x2 */
unsigned long sk_lingertime; /* 0x238 0x8 */
/* --- cacheline 9 boundary (576 bytes) --- */
struct proto * sk_prot_creator; /* 0x240 0x8 */
rwlock_t sk_callback_lock; /* 0x248 0x8 */
int sk_err_soft; /* 0x250 0x4 */
u32 sk_ack_backlog; /* 0x254 0x4 */
u32 sk_max_ack_backlog; /* 0x258 0x4 */
kuid_t sk_uid; /* 0x25c 0x4 */
spinlock_t sk_peer_lock; /* 0x260 0x4 */
int sk_bind_phc; /* 0x264 0x4 */
struct pid * sk_peer_pid; /* 0x268 0x8 */
const struct cred * sk_peer_cred; /* 0x270 0x8 */
ktime_t sk_stamp; /* 0x278 0x8 */
/* --- cacheline 10 boundary (640 bytes) --- */
int sk_disconnects; /* 0x280 0x4 */
u8 sk_txrehash; /* 0x284 0x1 */
u8 sk_clockid; /* 0x285 0x1 */
u8 sk_txtime_deadline_mode:1; /* 0x286: 0 0x1 */
u8 sk_txtime_report_errors:1; /* 0x286:0x1 0x1 */
u8 sk_txtime_unused:6; /* 0x286:0x2 0x1 */

/* XXX 1 byte hole, try to pack */

void * sk_user_data; /* 0x288 0x8 */
void * sk_security; /* 0x290 0x8 */
struct sock_cgroup_data sk_cgrp_data; /* 0x298 0x8 */
void (*sk_state_change)(struct sock *); /* 0x2a0 0x8 */
void (*sk_write_space)(struct sock *); /* 0x2a8 0x8 */
void (*sk_error_report)(struct sock *); /* 0x2b0 0x8 */
int (*sk_backlog_rcv)(struct sock *, struct sk_buff *); /* 0x2b8 0x8 */
/* --- cacheline 11 boundary (704 bytes) --- */
void (*sk_destruct)(struct sock *); /* 0x2c0 0x8 */
rcu * sk_reuseport_cb; /* 0x2c8 0x8 */
rcu * sk_bpf_storage; /* 0x2d0 0x8 */
struct callback_head sk_rcu __attribute__((__aligned__(8))); /* 0x2d8 0x10 */
netns_tracker ns_tracker; /* 0x2e8 0x8 */

/* size: 752, cachelines: 12, members: 105 */
/* sum members: 749, holes: 1, sum holes: 1 */
/* sum bitfield members: 12 bits, bit holes: 1, sum bit holes: 4 bits */
/* paddings: 1, sum paddings: 4 */
/* forced alignments: 1 */
/* last cacheline: 48 bytes */
};

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240216162006.2342759-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

show more ...

bpf: tcp: Support arbitrary SYN Cookie.

This patch adds a new kfunc available at TC hook to support arbitrary
SYN Cookie.

The basic usage is as follows:

struct bpf_tcp_req_attrs attrs = {

bpf: tcp: Support arbitrary SYN Cookie.

This patch adds a new kfunc available at TC hook to support arbitrary
SYN Cookie.

The basic usage is as follows:

struct bpf_tcp_req_attrs attrs = {
.mss = mss,
.wscale_ok = wscale_ok,
.rcv_wscale = rcv_wscale, /* Server's WScale < 15 */
.snd_wscale = snd_wscale, /* Client's WScale < 15 */
.tstamp_ok = tstamp_ok,
.rcv_tsval = tsval,
.rcv_tsecr = tsecr, /* Server's Initial TSval */
.usec_ts_ok = usec_ts_ok,
.sack_ok = sack_ok,
.ecn_ok = ecn_ok,
}

skc = bpf_skc_lookup_tcp(...);
sk = (struct sock *)bpf_skc_to_tcp_sock(skc);
bpf_sk_assign_tcp_reqsk(skb, sk, attrs, sizeof(attrs));
bpf_sk_release(skc);

bpf_sk_assign_tcp_reqsk() takes skb, a listener sk, and struct
bpf_tcp_req_attrs and allocates reqsk and configures it. Then,
bpf_sk_assign_tcp_reqsk() links reqsk with skb and the listener.

The notable thing here is that we do not hold refcnt for both reqsk
and listener. To differentiate that, we mark reqsk->syncookie, which
is only used in TX for now. So, if reqsk->syncookie is 1 in RX, it
means that the reqsk is allocated by kfunc.

When skb is freed, sock_pfree() checks if reqsk->syncookie is 1,
and in that case, we set NULL to reqsk->rsk_listener before calling
reqsk_free() as reqsk does not hold a refcnt of the listener.

When the TCP stack looks up a socket from the skb, we steal the
listener from the reqsk in skb_steal_sock() and create a full sk
in cookie_v[46]_check().

The refcnt of reqsk will finally be set to 1 in tcp_get_cookie_sock()
after creating a full sk.

Note that we can extend struct bpf_tcp_req_attrs in the future when
we add a new attribute that is determined in 3WHS.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240115205514.68364-6-kuniyu@amazon.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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udp: fix busy polling

Generic sk_busy_loop_end() only looks at sk->sk_receive_queue
for presence of packets.

Problem is that for UDP sockets after blamed commit, some packets
could be present in an

udp: fix busy polling

Generic sk_busy_loop_end() only looks at sk->sk_receive_queue
for presence of packets.

Problem is that for UDP sockets after blamed commit, some packets
could be present in another queue: udp_sk(sk)->reader_queue

In some cases, a busy poller could spin until timeout expiration,
even if some packets are available in udp_sk(sk)->reader_queue.

v3: - make sk_busy_loop_end() nicer (Willem)

v2: - add a READ_ONCE(sk->sk_family) in sk_is_inet() to avoid KCSAN splats.
- add a sk_is_inet() check in sk_is_udp() (Willem feedback)
- add a sk_is_inet() check in sk_is_tcp().

Fixes: 2276f58ac589 ("udp: use a separate rx queue for packet reception")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: Implement missing SO_TIMESTAMPING_NEW cmsg support

Commit 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW") added the new
socket option SO_TIMESTAMPING_NEW. However, it was never implemented in

net: Implement missing SO_TIMESTAMPING_NEW cmsg support

Commit 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW") added the new
socket option SO_TIMESTAMPING_NEW. However, it was never implemented in
__sock_cmsg_send thus breaking SO_TIMESTAMPING cmsg for platforms using
SO_TIMESTAMPING_NEW.

Fixes: 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW")
Link: https://lore.kernel.org/netdev/6a7281bf-bc4a-4f75-bb88-7011908ae471@app.fastmail.com/
Signed-off-by: Thomas Lange <thomas@corelatus.se>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240104085744.49164-1-thomas@corelatus.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: Implement missing getsockopt(SO_TIMESTAMPING_NEW)

Commit 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW") added the new
socket option SO_TIMESTAMPING_NEW. Setting the option is handled in
sk_se

net: Implement missing getsockopt(SO_TIMESTAMPING_NEW)

Commit 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW") added the new
socket option SO_TIMESTAMPING_NEW. Setting the option is handled in
sk_setsockopt(), querying it was not handled in sk_getsockopt(), though.

Following remarks on an earlier submission of this patch, keep the old
behavior of getsockopt(SO_TIMESTAMPING_OLD) which returns the active
flags even if they actually have been set through SO_TIMESTAMPING_NEW.

The new getsockopt(SO_TIMESTAMPING_NEW) is stricter, returning flags
only if they have been set through the same option.

Fixes: 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW")
Link: https://lore.kernel.org/lkml/20230703175048.151683-1-jthinz@mailbox.tu-berlin.de/
Link: https://lore.kernel.org/netdev/0d7cddc9-03fa-43db-a579-14f3e822615b@app.fastmail.com/
Signed-off-by: Jörn-Thorben Hinz <jthinz@mailbox.tu-berlin.de>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: Namespace-ify sysctl_optmem_max

optmem_max being used in tx zerocopy,
we want to be able to control it on a netns basis.

Following patch changes two tests.

Tested:

oqq130:~# cat /proc/sys/ne

net: Namespace-ify sysctl_optmem_max

optmem_max being used in tx zerocopy,
we want to be able to control it on a netns basis.

Following patch changes two tests.

Tested:

oqq130:~# cat /proc/sys/net/core/optmem_max
131072
oqq130:~# echo 1000000 >/proc/sys/net/core/optmem_max
oqq130:~# cat /proc/sys/net/core/optmem_max
1000000
oqq130:~# unshare -n
oqq130:~# cat /proc/sys/net/core/optmem_max
131072
oqq130:~# exit
logout
oqq130:~# cat /proc/sys/net/core/optmem_max
1000000

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: increase optmem_max default value

For many years, /proc/sys/net/core/optmem_max default value
on a 64bit kernel has been 20 KB.

Regular usage of TCP tx zerocopy needs a bit more.

Google has u

net: increase optmem_max default value

For many years, /proc/sys/net/core/optmem_max default value
on a 64bit kernel has been 20 KB.

Regular usage of TCP tx zerocopy needs a bit more.

Google has used 128KB as the default value for 7 years without
any problem.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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sock: Ignore memcg pressure heuristics when raising allocated

Before sockets became aware of net-memcg's memory pressure since
commit e1aab161e013 ("socket: initial cgroup code."), the memory
usage

sock: Ignore memcg pressure heuristics when raising allocated

Before sockets became aware of net-memcg's memory pressure since
commit e1aab161e013 ("socket: initial cgroup code."), the memory
usage would be granted to raise if below average even when under
protocol's pressure. This provides fairness among the sockets of
same protocol.

That commit changes this because the heuristic will also be
effective when only memcg is under pressure which makes no sense.
So revert that behavior.

After reverting, __sk_mem_raise_allocated() no longer considers
memcg's pressure. As memcgs are isolated from each other w.r.t.
memory accounting, consuming one's budget won't affect others.
So except the places where buffer sizes are needed to be tuned,
allow workloads to use the memory they are provisioned.

Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20231019120026.42215-3-wuyun.abel@bytedance.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

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sock: Doc behaviors for pressure heurisitics

There are now two accounting infrastructures for skmem, while the
heuristics in __sk_mem_raise_allocated() were actually introduced
before memcg was born

sock: Doc behaviors for pressure heurisitics

There are now two accounting infrastructures for skmem, while the
heuristics in __sk_mem_raise_allocated() were actually introduced
before memcg was born.

Add some comments to clarify whether they can be applied to both
infrastructures or not.

Suggested-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20231019120026.42215-2-wuyun.abel@bytedance.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

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sock: Code cleanup on __sk_mem_raise_allocated()

Code cleanup for both better simplicity and readability.
No functional change intended.

Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
Acked-by:

sock: Code cleanup on __sk_mem_raise_allocated()

Code cleanup for both better simplicity and readability.
No functional change intended.

Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20231019120026.42215-1-wuyun.abel@bytedance.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

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net/socket: Break down __sys_getsockopt

Split __sys_getsockopt() into two functions by removing the core
logic into a sub-function (do_sock_getsockopt()). This will avoid
code duplication when doing

net/socket: Break down __sys_getsockopt

Split __sys_getsockopt() into two functions by removing the core
logic into a sub-function (do_sock_getsockopt()). This will avoid
code duplication when doing the same operation in other callers, for
instance.

do_sock_getsockopt() will be called by io_uring getsockopt() command
operation in the following patch.

The same was done for the setsockopt pair.

Suggested-by: Martin KaFai Lau <martin.lau@linux.dev>
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20231016134750.1381153-5-leitao@debian.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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net: annotate data-races around sk->sk_dst_pending_confirm

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumaze

net: annotate data-races around sk->sk_dst_pending_confirm

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: lockless implementation of SO_TXREHASH

sk->sk_txrehash readers are already safe against
concurrent change of this field.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David

net: lockless implementation of SO_TXREHASH

sk->sk_txrehash readers are already safe against
concurrent change of this field.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: implement lockless SO_MAX_PACING_RATE

SO_MAX_PACING_RATE setsockopt() does not need to hold
the socket lock, because sk->sk_pacing_rate readers
can run fine if the value is changed by other thr

net: implement lockless SO_MAX_PACING_RATE

SO_MAX_PACING_RATE setsockopt() does not need to hold
the socket lock, because sk->sk_pacing_rate readers
can run fine if the value is changed by other threads,
after adding READ_ONCE() accessors.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: lockless implementation of SO_BUSY_POLL, SO_PREFER_BUSY_POLL, SO_BUSY_POLL_BUDGET

Setting sk->sk_ll_usec, sk_prefer_busy_poll and sk_busy_poll_budget
do not require the socket lock, readers are

net: lockless implementation of SO_BUSY_POLL, SO_PREFER_BUSY_POLL, SO_BUSY_POLL_BUDGET

Setting sk->sk_ll_usec, sk_prefer_busy_poll and sk_busy_poll_budget
do not require the socket lock, readers are lockless anyway.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: lockless SO_{TYPE|PROTOCOL|DOMAIN|ERROR } setsockopt()

This options can not be set and return -ENOPROTOOPT,
no need to acqure socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Sig

net: lockless SO_{TYPE|PROTOCOL|DOMAIN|ERROR } setsockopt()

This options can not be set and return -ENOPROTOOPT,
no need to acqure socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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