linux/include/net/tls.h, branch v5.4

net/tls: enable sk_msg redirect to tls socket egress

2019-11-19T23:03:02Z

Bring back tls_sw_sendpage_locked. sk_msg redirection into a socket with TLS_TX takes the following path: tcp_bpf_sendmsg_redir tcp_bpf_push_locked tcp_bpf_push kernel_sendpage_locked sock->ops->sendpage_locked Also update the flags test in tls_sw_sendpage_locked to allow flag MSG_NO_SHARED_FRAGS. bpf_tcp_sendmsg sets this. Link: https://lore.kernel.org/netdev/CA+FuTSdaAawmZ2N8nfDDKu3XLpXBbMtcCT0q4FntDD2gn8ASUw@mail.gmail.com/T/#t Link: https://github.com/wdebruij/kerneltools/commits/icept.2 Fixes: 0608c69c9a80 ("bpf: sk_msg, sock{map|hash} redirect through ULP") Fixes: f3de19af0f5b ("Revert \"net/tls: remove unused function tls_sw_sendpage_locked\"") Signed-off-by: Willem de Bruijn Acked-by: John Fastabend Signed-off-by: David S. Miller

net/tls: add a TX lock

2019-11-07T01:33:32Z

TLS TX needs to release and re-acquire the socket lock if send buffer fills up. TLS SW TX path currently depends on only allowing one thread to enter the function by the abuse of sk_write_pending. If another writer is already waiting for memory no new ones are allowed in. This has two problems: - writers don't wake other threads up when they leave the kernel; meaning that this scheme works for single extra thread (second application thread or delayed work) because memory becoming available will send a wake up request, but as Mallesham and Pooja report with larger number of threads it leads to threads being put to sleep indefinitely; - the delayed work does not get _scheduled_ but it may _run_ when other writers are present leading to crashes as writers don't expect state to change under their feet (same records get pushed and freed multiple times); it's hard to reliably bail from the work, however, because the mere presence of a writer does not guarantee that the writer will push pending records before exiting. Ensuring wakeups always happen will make the code basically open code a mutex. Just use a mutex. The TLS HW TX path does not have any locking (not even the sk_write_pending hack), yet it uses a per-socket sg_tx_data array to push records. Fixes: a42055e8d2c3 ("net/tls: Add support for async encryption of records for performance") Reported-by: Mallesham Jatharakonda Reported-by: Pooja Trivedi Signed-off-by: Jakub Kicinski Reviewed-by: Simon Horman Signed-off-by: David S. Miller

net/tls: clean up the number of #ifdefs for CONFIG_TLS_DEVICE

2019-09-05T07:49:49Z

TLS code has a number of #ifdefs which make the code a little harder to follow. Recent fixes removed the ifdef around the TLS_HW define, so we can switch to the often used pattern of defining tls_device functions as empty static inlines in the header when CONFIG_TLS_DEVICE=n. Signed-off-by: Jakub Kicinski Reviewed-by: John Hurley Reviewed-by: Dirk van der Merwe Acked-by: John Fastabend Signed-off-by: David S. Miller

net/tls: use the full sk_proto pointer

2019-09-05T07:49:49Z

Since we already have the pointer to the full original sk_proto stored use that instead of storing all individual callback pointers as well. Signed-off-by: Jakub Kicinski Reviewed-by: John Hurley Reviewed-by: Dirk van der Merwe Acked-by: John Fastabend Signed-off-by: David S. Miller

net: tls: export protocol version, cipher, tx_conf/rx_conf to socket diag

2019-09-01T06:44:28Z

When an application configures kernel TLS on top of a TCP socket, it's now possible for inet_diag_handler() to collect information regarding the protocol version, the cipher type and TX / RX configuration, in case INET_DIAG_INFO is requested. Signed-off-by: Davide Caratti Reviewed-by: Jakub Kicinski Signed-off-by: David S. Miller

net/tls: use RCU protection on icsk->icsk_ulp_data

2019-09-01T06:44:28Z

We need to make sure context does not get freed while diag code is interrogating it. Free struct tls_context with kfree_rcu(). We add the __rcu annotation directly in icsk, and cast it away in the datapath accessor. Presumably all ULPs will do a similar thing. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

net/tls: partially revert fix transition through disconnect with close

2019-08-05T20:15:30Z

Looks like we were slightly overzealous with the shutdown() cleanup. Even though the sock->sk_state can reach CLOSED again, socket->state will not got back to SS_UNCONNECTED once connections is ESTABLISHED. Meaning we will see EISCONN if we try to reconnect, and EINVAL if we try to listen. Only listen sockets can be shutdown() and reused, but since ESTABLISHED sockets can never be re-connected() or used for listen() we don't need to try to clean up the ULP state early. Fixes: 32857cf57f92 ("net/tls: fix transition through disconnect with close") Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

net/tls: fix transition through disconnect with close

2019-07-22T14:04:17Z

It is possible (via shutdown()) for TCP socks to go through TCP_CLOSE state via tcp_disconnect() without actually calling tcp_close which would then call the tls close callback. Because of this a user could disconnect a socket then put it in a LISTEN state which would break our assumptions about sockets always being ESTABLISHED state. More directly because close() can call unhash() and unhash is implemented by sockmap if a sockmap socket has TLS enabled we can incorrectly destroy the psock from unhash() and then call its close handler again. But because the psock (sockmap socket representation) is already destroyed we call close handler in sk->prot. However, in some cases (TLS BASE/BASE case) this will still point at the sockmap close handler resulting in a circular call and crash reported by syzbot. To fix both above issues implement the unhash() routine for TLS. v4: - add note about tls offload still needing the fix; - move sk_proto to the cold cache line; - split TX context free into "release" and "free", otherwise the GC work itself is in already freed memory; - more TX before RX for consistency; - reuse tls_ctx_free(); - schedule the GC work after we're done with context to avoid UAF; - don't set the unhash in all modes, all modes "inherit" TLS_BASE's callbacks anyway; - disable the unhash hook for TLS_HW. Fixes: 3c4d7559159bf ("tls: kernel TLS support") Reported-by: Eric Dumazet Signed-off-by: John Fastabend Signed-off-by: Jakub Kicinski Signed-off-by: Daniel Borkmann

net/tls: remove sock unlock/lock around strp_done()

2019-07-22T14:04:16Z

The tls close() callback currently drops the sock lock to call strp_done(). Split up the RX cleanup into stopping the strparser and releasing most resources, syncing strparser and finally freeing the context. To avoid the need for a strp_done() call on the cleanup path of device offload make sure we don't arm the strparser until we are sure init will be successful. Signed-off-by: John Fastabend Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Signed-off-by: Daniel Borkmann

net/tls: remove close callback sock unlock/lock around TX work flush

2019-07-22T14:04:16Z

The tls close() callback currently drops the sock lock, makes a cancel_delayed_work_sync() call, and then relocks the sock. By restructuring the code we can avoid droping lock and then reclaiming it. To simplify this we do the following, tls_sk_proto_close set_bit(CLOSING) set_bit(SCHEDULE) cancel_delay_work_sync() <- cancel workqueue lock_sock(sk) ... release_sock(sk) strp_done() Setting the CLOSING bit prevents the SCHEDULE bit from being cleared by any workqueue items e.g. if one happens to be scheduled and run between when we set SCHEDULE bit and cancel work. Then because SCHEDULE bit is set now no new work will be scheduled. Tested with net selftests and bpf selftests. Signed-off-by: John Fastabend Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Signed-off-by: Daniel Borkmann