From: Jakub Kicinski <kuba@kernel.org>
Date: Mon, 20 Jun 2022 12:13:53 -0700
Subject: sock: redo the psock vs ULP protection check
Patch-mainline: v5.19-rc4
Git-commit: e34a07c0ae3906f97eb18df50902e2a01c1015b6
References: jsc#PED-1377
Commit 8a59f9d1e3d4 ("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: 8a59f9d1e3d4 ("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>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
include/net/inet_sock.h | 5 +++++
net/core/skmsg.c | 5 +++++
net/ipv4/tcp_bpf.c | 3 ---
net/tls/tls_main.c | 2 ++
4 files changed, 12 insertions(+), 3 deletions(-)
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -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
--- a/net/core/skmsg.c
+++ b/net/core/skmsg.c
@@ -699,6 +699,11 @@ struct sk_psock *sk_psock_init(struct so
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;
--- a/net/ipv4/tcp_bpf.c
+++ b/net/ipv4/tcp_bpf.c
@@ -612,9 +612,6 @@ int tcp_bpf_update_proto(struct sock *sk
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;
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -753,6 +753,8 @@ static void tls_update(struct sock *sk,
{
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;