sock: redo the psock vs ULP protection check

Commit 8a59f9d1e3 ("sock: Introduce sk->sk_prot->psock_update_sk_prot()")
has moved the inet_csk_has_ulp(sk) check from sk_psock_init() to
the new tcp_bpf_update_proto() function. I'm guessing that this
was done to allow creating psocks for non-inet sockets.

Unfortunately the destruction path for psock includes the ULP
unwind, so we need to fail the sk_psock_init() itself.
Otherwise if ULP is already present we'll notice that later,
and call tcp_update_ulp() with the sk_proto of the ULP
itself, which will most likely result in the ULP looping
its callbacks.

Fixes: 8a59f9d1e3 ("sock: Introduce sk->sk_prot->psock_update_sk_prot()")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Tested-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/r/20220620191353.1184629-2-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Jakub Kicinski 2022-06-20 12:13:53 -07:00 committed by Paolo Abeni
parent 1b205d948f
commit e34a07c0ae
4 changed files with 12 additions and 3 deletions

View File

@ -253,6 +253,11 @@ struct inet_sock {
#define IP_CMSG_CHECKSUM BIT(7)
#define IP_CMSG_RECVFRAGSIZE BIT(8)
static inline bool sk_is_inet(struct sock *sk)
{
return sk->sk_family == AF_INET || sk->sk_family == AF_INET6;
}
/**
* sk_to_full_sk - Access to a full socket
* @sk: pointer to a socket

View File

@ -699,6 +699,11 @@ struct sk_psock *sk_psock_init(struct sock *sk, int node)
write_lock_bh(&sk->sk_callback_lock);
if (sk_is_inet(sk) && inet_csk_has_ulp(sk)) {
psock = ERR_PTR(-EINVAL);
goto out;
}
if (sk->sk_user_data) {
psock = ERR_PTR(-EBUSY);
goto out;

View File

@ -611,9 +611,6 @@ int tcp_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore)
return 0;
}
if (inet_csk_has_ulp(sk))
return -EINVAL;
if (sk->sk_family == AF_INET6) {
if (tcp_bpf_assert_proto_ops(psock->sk_proto))
return -EINVAL;

View File

@ -921,6 +921,8 @@ static void tls_update(struct sock *sk, struct proto *p,
{
struct tls_context *ctx;
WARN_ON_ONCE(sk->sk_prot == p);
ctx = tls_get_ctx(sk);
if (likely(ctx)) {
ctx->sk_write_space = write_space;