Commit 5459cce6 authored by Jiayuan Chen's avatar Jiayuan Chen Committed by Martin KaFai Lau
Browse files

bpf: Disable non stream socket for strparser 



Currently, only TCP supports strparser, but sockmap doesn't intercept
non-TCP connections to attach strparser. For example, with UDP, although
the read/write handlers are replaced, strparser is not executed due to
the lack of a read_sock operation.

Furthermore, in udp_bpf_recvmsg(), it checks whether the psock has data,
and if not, it falls back to the native UDP read interface, making
UDP + strparser appear to read correctly. According to its commit history,
this behavior is unexpected.

Moreover, since UDP lacks the concept of streams, we intercept it directly.

Fixes: 1fa1fe8f ("bpf, sockmap: Test shutdown() correctly exits epoll and recv()=0")
Signed-off-by: default avatarJiayuan Chen <mrpre@163.com>
Signed-off-by: default avatarMartin KaFai Lau <martin.lau@kernel.org>
Acked-by: default avatarJakub Sitnicki <jakub@cloudflare.com>
Acked-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Link: https://patch.msgid.link/20250122100917.49845-4-mrpre@163.com
parent 36b62df5

net/core/sock_map.c

+4 −1
Original line number Diff line number Diff line
@@ -303,7 +303,10 @@ static int sock_map_link(struct bpf_map *map, struct sock *sk) 


	write_lock_bh(&sk->sk_callback_lock);

	if (stream_parser && stream_verdict && !psock->saved_data_ready) {

		if (sk_is_tcp(sk))

			ret = sk_psock_init_strp(sk, psock);

		else

			ret = -EOPNOTSUPP;

		if (ret) {

			write_unlock_bh(&sk->sk_callback_lock);

			sk_psock_put(sk, psock);