diff options
author | Zijian Zhang <zijianzhang@bytedance.com> | 2024-12-10 02:20:39 +0100 |
---|---|---|
committer | Daniel Borkmann <daniel@iogearbox.net> | 2024-12-20 17:59:47 +0100 |
commit | d888b7af7c149c115dd6ac772cc11c375da3e17c (patch) | |
tree | 3075d7547e00e87264452341055b410b4068d5e4 /net/ipv4 | |
parent | tcp_bpf: Charge receive socket buffer in bpf_tcp_ingress() (diff) | |
download | linux-d888b7af7c149c115dd6ac772cc11c375da3e17c.tar.xz linux-d888b7af7c149c115dd6ac772cc11c375da3e17c.zip |
tcp_bpf: Add sk_rmem_alloc related logic for tcp_bpf ingress redirection
When we do sk_psock_verdict_apply->sk_psock_skb_ingress, an sk_msg will
be created out of the skb, and the rmem accounting of the sk_msg will be
handled by the skb.
For skmsgs in __SK_REDIRECT case of tcp_bpf_send_verdict, when redirecting
to the ingress of a socket, although we sk_rmem_schedule and add sk_msg to
the ingress_msg of sk_redir, we do not update sk_rmem_alloc. As a result,
except for the global memory limit, the rmem of sk_redir is nearly
unlimited. Thus, add sk_rmem_alloc related logic to limit the recv buffer.
Since the function sk_msg_recvmsg and __sk_psock_purge_ingress_msg are
used in these two paths. We use "msg->skb" to test whether the sk_msg is
skb backed up. If it's not, we shall do the memory accounting explicitly.
Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Zijian Zhang <zijianzhang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20241210012039.1669389-3-zijianzhang@bytedance.com
Diffstat (limited to 'net/ipv4')
-rw-r--r-- | net/ipv4/tcp_bpf.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index b21ea634909c..392678ae80f4 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -56,6 +56,7 @@ static int bpf_tcp_ingress(struct sock *sk, struct sk_psock *psock, } sk_mem_charge(sk, size); + atomic_add(size, &sk->sk_rmem_alloc); sk_msg_xfer(tmp, msg, i, size); copied += size; if (sge->length) @@ -74,7 +75,8 @@ static int bpf_tcp_ingress(struct sock *sk, struct sk_psock *psock, if (!ret) { msg->sg.start = i; - sk_psock_queue_msg(psock, tmp); + if (!sk_psock_queue_msg(psock, tmp)) + atomic_sub(copied, &sk->sk_rmem_alloc); sk_psock_data_ready(sk, psock); } else { sk_msg_free(sk, tmp); |