kernel/linux.git/include/net/inet_hashtables.h, branch v6.9.12

tcp: Remove dead code and fields for bhash2.

2023-12-22T22:15:35+00:00

Now all sockets including TIME_WAIT are linked to bhash2 using sock_common.skc_bind_node. We no longer use inet_bind2_bucket.deathrow, sock.sk_bind2_node, and inet_timewait_sock.tw_bind2_node. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: Unlink sk from bhash.

2023-12-22T22:15:35+00:00

Now we do not use tb->owners and can unlink sockets from bhash. sk_bind_node/tw_bind_node are available for bhash2 and will be used in the following patch. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: Link bhash2 to bhash.

2023-12-22T22:15:34+00:00

bhash2 added a new member sk_bind2_node in struct sock to link sockets to bhash2 in addition to bhash. bhash is still needed to search conflicting sockets efficiently from a port for the wildcard address. However, bhash itself need not have sockets. If we link each bhash2 bucket to the corresponding bhash bucket, we can iterate the same set of the sockets from bhash2 via bhash. This patch links bhash2 to bhash only, and the actual use will be in the later patches. Finally, we will remove sk_bind2_node. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: Save address type in inet_bind2_bucket.

2023-12-22T22:15:34+00:00

inet_bind2_bucket_addr_match() and inet_bind2_bucket_match_addr_any() are called for each bhash2 bucket to check conflicts. Thus, we call ipv6_addr_any() and ipv6_addr_v4mapped() over and over during bind(). Let's avoid calling them by saving the address type in inet_bind2_bucket. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: Save v4 address as v4-mapped-v6 in inet_bind2_bucket.v6_rcv_saddr.

2023-12-22T22:15:34+00:00

In bhash2, IPv4/IPv6 addresses are saved in two union members, which complicate address checks in inet_bind2_bucket_addr_match() and inet_bind2_bucket_match_addr_any() considering uninitialised memory and v4-mapped-v6 conflicts. Let's simplify that by saving IPv4 address as v4-mapped-v6 address and defining tb2.rcv_saddr as tb2.v6_rcv_saddr.s6_addr32[3]. Then, we can compare v6 address as is, and after checking v4-mapped-v6, we can compare v4 address easily. Also, we can remove tb2->family. Note these functions will be further refactored in the next patch. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

net: Fix slab-out-of-bounds in inet[6]_steal_sock

2023-08-15T20:57:51+00:00

Kumar reported a KASAN splat in tcp_v6_rcv: bash-5.2# ./test_progs -t btf_skc_cls_ingress ... [ 51.810085] BUG: KASAN: slab-out-of-bounds in tcp_v6_rcv+0x2d7d/0x3440 [ 51.810458] Read of size 2 at addr ffff8881053f038c by task test_progs/226 The problem is that inet[6]_steal_sock accesses sk->sk_protocol without accounting for request or timewait sockets. To fix this we can't just check sock_common->skc_reuseport since that flag is present on timewait sockets. Instead, add a fullsock check to avoid the out of bands access of sk_protocol. Fixes: 9c02bec95954 ("bpf, net: Support SO_REUSEPORT sockets with bpf_sk_assign") Reported-by: Kumar Kartikeya Dwivedi Signed-off-by: Lorenz Bauer Link: https://lore.kernel.org/r/20230815-bpf-next-v2-1-95126eaa4c1b@isovalent.com Signed-off-by: Martin KaFai Lau

tcp/dccp: cache line align inet_hashinfo

2023-08-04T08:20:27+00:00

I have seen tcp_hashinfo starting at a non optimal location, forcing input handlers to pull two cache lines instead of one, and sharing a cache line that was dirtied more than necessary: ffffffff83680600 b tcp_orphan_timer ffffffff83680628 b tcp_orphan_cache ffffffff8368062c b tcp_enable_tx_delay.__tcp_tx_delay_enabled ffffffff83680630 B tcp_hashinfo ffffffff83680680 b tcp_cong_list_lock After this patch, ehash, ehash_locks, ehash_mask and ehash_locks_mask are located in a read-only cache line. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

bpf, net: Support SO_REUSEPORT sockets with bpf_sk_assign

2023-07-25T20:55:55+00:00

Currently the bpf_sk_assign helper in tc BPF context refuses SO_REUSEPORT sockets. This means we can't use the helper to steer traffic to Envoy, which configures SO_REUSEPORT on its sockets. In turn, we're blocked from removing TPROXY from our setup. The reason that bpf_sk_assign refuses such sockets is that the bpf_sk_lookup helpers don't execute SK_REUSEPORT programs. Instead, one of the reuseport sockets is selected by hash. This could cause dispatch to the "wrong" socket: sk = bpf_sk_lookup_tcp(...) // select SO_REUSEPORT by hash bpf_sk_assign(skb, sk) // SK_REUSEPORT wasn't executed Fixing this isn't as simple as invoking SK_REUSEPORT from the lookup helpers unfortunately. In the tc context, L2 headers are at the start of the skb, while SK_REUSEPORT expects L3 headers instead. Instead, we execute the SK_REUSEPORT program when the assigned socket is pulled out of the skb, further up the stack. This creates some trickiness with regards to refcounting as bpf_sk_assign will put both refcounted and RCU freed sockets in skb->sk. reuseport sockets are RCU freed. We can infer that the sk_assigned socket is RCU freed if the reuseport lookup succeeds, but convincing yourself of this fact isn't straight forward. Therefore we defensively check refcounting on the sk_assign sock even though it's probably not required in practice. Fixes: 8e368dc72e86 ("bpf: Fix use of sk->sk_reuseport from sk_assign") Fixes: cf7fbe660f2d ("bpf: Add socket assign support") Co-developed-by: Daniel Borkmann Signed-off-by: Daniel Borkmann Cc: Joe Stringer Link: https://lore.kernel.org/bpf/CACAyw98+qycmpQzKupquhkxbvWK4OFyDuuLMBNROnfWMZxUWeA@mail.gmail.com/ Reviewed-by: Kuniyuki Iwashima Signed-off-by: Lorenz Bauer Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-7-7021b683cdae@isovalent.com Signed-off-by: Martin KaFai Lau

net: remove duplicate sk_lookup helpers

2023-07-25T20:51:44+00:00

Now that inet[6]_lookup_reuseport are parameterised on the ehashfn we can remove two sk_lookup helpers. Reviewed-by: Kuniyuki Iwashima Signed-off-by: Lorenz Bauer Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-6-7021b683cdae@isovalent.com Signed-off-by: Martin KaFai Lau

net: remove duplicate reuseport_lookup functions

2023-07-25T20:51:44+00:00

There are currently four copies of reuseport_lookup: one each for (TCP, UDP)x(IPv4, IPv6). This forces us to duplicate all callers of those functions as well. This is already the case for sk_lookup helpers (inet,inet6,udp4,udp6)_lookup_run_bpf. There are two differences between the reuseport_lookup helpers: 1. They call different hash functions depending on protocol 2. UDP reuseport_lookup checks that sk_state != TCP_ESTABLISHED Move the check for sk_state into the caller and use the INDIRECT_CALL infrastructure to cut down the helpers to one per IP version. Reviewed-by: Kuniyuki Iwashima Signed-off-by: Lorenz Bauer Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-4-7021b683cdae@isovalent.com Signed-off-by: Martin KaFai Lau