diff options
| author | Zijian Zhang <zijianzhang@bytedance.com> | 2024-12-10 04:20:39 +0300 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2024-12-20 19:59:47 +0300 |
| commit | d888b7af7c149c115dd6ac772cc11c375da3e17c (patch) | |
| tree | 3075d7547e00e87264452341055b410b4068d5e4 /net/core | |
| parent | 54f89b3178d5448dd4457afbb98fc1ab99090a65 (diff) | |
| download | linux-d888b7af7c149c115dd6ac772cc11c375da3e17c.tar.xz | |
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/core')
| -rw-r--r-- | net/core/skmsg.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/core/skmsg.c b/net/core/skmsg.c index e90fbab703b2..8ad7e6755fd6 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -445,8 +445,10 @@ int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg, if (likely(!peek)) { sge->offset += copy; sge->length -= copy; - if (!msg_rx->skb) + if (!msg_rx->skb) { sk_mem_uncharge(sk, copy); + atomic_sub(copy, &sk->sk_rmem_alloc); + } msg_rx->sg.size -= copy; if (!sge->length) { @@ -772,6 +774,8 @@ static void __sk_psock_purge_ingress_msg(struct sk_psock *psock) list_for_each_entry_safe(msg, tmp, &psock->ingress_msg, list) { list_del(&msg->list); + if (!msg->skb) + atomic_sub(msg->sg.size, &psock->sk->sk_rmem_alloc); sk_msg_free(psock->sk, msg); kfree(msg); } |