tcp_bpf: Don't let child socket inherit parent protocol ops on copy

Prepare for cloning listening sockets that have their protocol callbacks
overridden by sk_msg. Child sockets must not inherit parent callbacks that
access state stored in sk_user_data owned by the parent.

Restore the child socket protocol callbacks before it gets hashed and any
of the callbacks can get invoked.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200218171023.844439-4-jakub@cloudflare.com
This commit is contained in:
Jakub Sitnicki
2020-02-18 17:10:15 +00:00
committed by Daniel Borkmann
parent f1ff5ce2cd
commit e80251555f
3 changed files with 23 additions and 0 deletions

View File

@@ -2203,6 +2203,13 @@ int tcp_bpf_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
int nonblock, int flags, int *addr_len);
int __tcp_bpf_recvmsg(struct sock *sk, struct sk_psock *psock,
struct msghdr *msg, int len, int flags);
#ifdef CONFIG_NET_SOCK_MSG
void tcp_bpf_clone(const struct sock *sk, struct sock *newsk);
#else
static inline void tcp_bpf_clone(const struct sock *sk, struct sock *newsk)
{
}
#endif
/* Call BPF_SOCK_OPS program that returns an int. If the return value
* is < 0, then the BPF op failed (for example if the loaded BPF