kernel/net/ipv4/tcp_diag.c, branch linux-6.2.y

tcp: Access &tcp_hashinfo via net.

2022-09-20T17:21:49Z

We will soon introduce an optional per-netns ehash. This means we cannot use tcp_hashinfo directly in most places. Instead, access it via net->ipv4.tcp_death_row.hashinfo. The access will be valid only while initialising tcp_hashinfo itself and creating/destroying each netns. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski

inet_diag: Move the INET_DIAG_REQ_BYTECODE nlattr to cb->data

2020-02-28T02:50:19Z

The INET_DIAG_REQ_BYTECODE nlattr is currently re-found every time when the "dump()" is re-started. In a latter patch, it will also need to parse the new INET_DIAG_REQ_SK_BPF_STORAGES nlattr to learn the map_fds. Thus, this patch takes this chance to store the parsed nlattr in cb->data during the "start" time of a dump. By doing this, the "bc" argument also becomes unnecessary and is removed. Also, the two copies of the INET_DIAG_REQ_BYTECODE parsing-audit logic between compat/current version can be consolidated to one. Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200225230415.1975555-1-kafai@fb.com

inet_diag: Refactor inet_sk_diag_fill(), dump(), and dump_one()

2020-02-28T02:50:19Z

In a latter patch, there is a need to update "cb->min_dump_alloc" in inet_sk_diag_fill() as it learns the diffierent bpf_sk_storages stored in a sk while dumping all sk(s) (e.g. tcp_hashinfo). The inet_sk_diag_fill() currently does not take the "cb" as an argument. One of the reason is inet_sk_diag_fill() is used by both dump_one() and dump() (which belong to the "struct inet_diag_handler". The dump_one() interface does not pass the "cb" along. This patch is to make dump_one() pass a "cb". The "cb" is created in inet_diag_cmd_exact(). The "nlh" and "in_skb" are stored in "cb" as the dump() interface does. The total number of args in inet_sk_diag_fill() is also cut from 10 to 7 and that helps many callers to pass fewer args. In particular, "struct user_namespace *user_ns", "u32 pid", and "u32 seq" can be replaced by accessing "cb->nlh" and "cb->skb". A similar argument reduction is also made to inet_twsk_diag_fill() and inet_req_diag_fill(). inet_csk_diag_dump() and inet_csk_diag_fill() are also removed. They are mostly equivalent to inet_sk_diag_fill(). Their repeated usages are very limited. Thus, inet_sk_diag_fill() is directly used in those occasions. Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200225230409.1975173-1-kafai@fb.com

net: annotate lockless accesses to sk->sk_max_ack_backlog

2019-11-07T00:14:48Z

sk->sk_max_ack_backlog can be read without any lock being held at least in TCP/DCCP cases. We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing and/or potential KCSAN warnings. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net: annotate lockless accesses to sk->sk_ack_backlog

2019-11-07T00:14:48Z

sk->sk_ack_backlog can be read without any lock being held. We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing and/or potential KCSAN warnings. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: annotate tp->write_seq lockless reads

2019-10-13T17:13:08Z

There are few places where we fetch tp->write_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: annotate tp->copied_seq lockless reads

2019-10-13T17:13:08Z

There are few places where we fetch tp->copied_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that tcp_inq_hint() was already using READ_ONCE(tp->copied_seq) Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: annotate tp->rcv_nxt lockless reads

2019-10-13T17:13:08Z

There are few places where we fetch tp->rcv_nxt while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that tcp_inq_hint() was already using READ_ONCE(tp->rcv_nxt) syzbot reported : BUG: KCSAN: data-race in tcp_poll / tcp_queue_rcv write to 0xffff888120425770 of 4 bytes by interrupt on cpu 0: tcp_rcv_nxt_update net/ipv4/tcp_input.c:3365 [inline] tcp_queue_rcv+0x180/0x380 net/ipv4/tcp_input.c:4638 tcp_rcv_established+0xbf1/0xf50 net/ipv4/tcp_input.c:5616 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1542 tcp_v4_rcv+0x1a03/0x1bf0 net/ipv4/tcp_ipv4.c:1923 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208 napi_skb_finish net/core/dev.c:5671 [inline] napi_gro_receive+0x28f/0x330 net/core/dev.c:5704 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061 read to 0xffff888120425770 of 4 bytes by task 7254 on cpu 1: tcp_stream_is_readable net/ipv4/tcp.c:480 [inline] tcp_poll+0x204/0x6b0 net/ipv4/tcp.c:554 sock_poll+0xed/0x250 net/socket.c:1256 vfs_poll include/linux/poll.h:90 [inline] ep_item_poll.isra.0+0x90/0x190 fs/eventpoll.c:892 ep_send_events_proc+0x113/0x5c0 fs/eventpoll.c:1749 ep_scan_ready_list.constprop.0+0x189/0x500 fs/eventpoll.c:704 ep_send_events fs/eventpoll.c:1793 [inline] ep_poll+0xe3/0x900 fs/eventpoll.c:1930 do_epoll_wait+0x162/0x180 fs/eventpoll.c:2294 __do_sys_epoll_pwait fs/eventpoll.c:2325 [inline] __se_sys_epoll_pwait fs/eventpoll.c:2311 [inline] __x64_sys_epoll_pwait+0xcd/0x170 fs/eventpoll.c:2311 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7254 Comm: syz-fuzzer Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller

tcp: ulp: fix possible crash in tcp_diag_get_aux_size()

2019-09-07T15:32:28Z

tcp_diag_get_aux_size() can be called with sockets in any state. icsk_ulp_ops is only present for full sockets. For SYN_RECV or TIME_WAIT ones we would access garbage. Fixes: 61723b393292 ("tcp: ulp: add functions to dump ulp-specific information") Signed-off-by: Eric Dumazet Reported-by: Luke Hsiao Reported-by: Neal Cardwell Cc: Davide Caratti Acked-by: Davide Caratti Signed-off-by: David S. Miller

tcp: ulp: add functions to dump ulp-specific information

2019-09-01T06:44:28Z

currently, only getsockopt(TCP_ULP) can be invoked to know if a ULP is on top of a TCP socket. Extend idiag_get_aux() and idiag_get_aux_size(), introduced by commit b37e88407c1d ("inet_diag: allow protocols to provide additional data"), to report the ULP name and other information that can be made available by the ULP through optional functions. Users having CAP_NET_ADMIN privileges will then be able to retrieve this information through inet_diag_handler, if they specify INET_DIAG_INFO in the request. Signed-off-by: Davide Caratti Signed-off-by: David S. Miller