kernel/linux.git/include/net/tls.h, branch linux-5.3.y

net/tls: use sg_next() to walk sg entries

2019-12-04T21:34:25+00:00

[ Upstream commit c5daa6cccdc2f94aca2c9b3fa5f94e4469997293 ] Partially sent record cleanup path increments an SG entry directly instead of using sg_next(). This should not be a problem today, as encrypted messages should be always allocated as arrays. But given this is a cleanup path it's easy to miss was this ever to change. Use sg_next(), and simplify the code. Signed-off-by: Jakub Kicinski Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net/tls: remove the dead inplace_crypto code

2019-12-04T21:34:24+00:00

[ Upstream commit 9e5ffed37df68d0ccfb2fdc528609e23a1e70ebe ] Looks like when BPF support was added by commit d3b18ad31f93 ("tls: add bpf support to sk_msg handling") and commit d829e9c4112b ("tls: convert to generic sk_msg interface") it broke/removed the support for in-place crypto as added by commit 4e6d47206c32 ("tls: Add support for inplace records encryption"). The inplace_crypto member of struct tls_rec is dead, inited to zero, and sometimes set to zero again. It used to be set to 1 when record was allocated, but the skmsg code doesn't seem to have been written with the idea of in-place crypto in mind. Since non trivial effort is required to bring the feature back and we don't really have the HW to measure the benefit just remove the left over support for now to avoid confusing readers. Signed-off-by: Jakub Kicinski Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net/tls: enable sk_msg redirect to tls socket egress

2019-11-29T09:07:37+00:00

[ Upstream commit d4ffb02dee2fcb20e0c8086a8d1305bf885820bb ] 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 Signed-off-by: Greg Kroah-Hartman

net/tls: add a TX lock

2019-11-12T18:26:46+00:00

[ Upstream commit 79ffe6087e9145d2377385cac48d0d6a6b4225a5 ] 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 Signed-off-by: Greg Kroah-Hartman

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

2019-08-05T20:15:30+00:00

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

2019-07-22T14:04:17+00:00

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()

2019-07-22T14:04:16+00:00

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

2019-07-22T14:04:16+00:00

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

net/tls: don't arm strparser immediately in tls_set_sw_offload()

2019-07-22T14:04:16+00:00

In tls_set_device_offload_rx() we prepare the software context for RX fallback and proceed to add the connection to the device. Unfortunately, software context prep includes arming strparser so in case of a later error we have to release the socket lock to call strp_done(). In preparation for not releasing the socket lock half way through callbacks move arming strparser into a separate function. Following patches will make use of that. Signed-off-by: Jakub Kicinski Reviewed-by: Dirk van der Merwe Signed-off-by: Daniel Borkmann

net/tls: don't clear TX resync flag on error

2019-07-09T03:21:09+00:00

Introduce a return code for the tls_dev_resync callback. When the driver TX resync fails, kernel can retry the resync again until it succeeds. This prevents drivers from attempting to offload TLS packets if the connection is known to be out of sync. We don't worry about the RX resync since they will be retried naturally as more encrypted records get received. Signed-off-by: Dirk van der Merwe Reviewed-by: Jakub Kicinski Signed-off-by: David S. Miller