[PATCH net-next v10 0/7] tls: receive-path fixes and clean-ups

[Chuck Lever <cel@kernel.org>]

I'd like to encourage in-kernel kTLS consumers (NFSD, NVMe/TCP) to
coalesce on the use of read_sock. While auditing read_sock for that
purpose, Hannes flagged a few rough edges in the receive paths.

This series is a set of clean-ups, not a performance series. Async
batch decryption and its submit/deliver scaffolding were dropped
during previous review: async_capable is always false for TLS 1.3,
the version NFSD and NVMe/TCP both require, so async-related
improvements were unreachable for the in-kernel consumers this
work targets.

A subsequent series will introduce infrastructure to support
KeyUpdate for in-kernel kTLS consumers, which need to handle TLS
Alert messages that trigger a tlshd upcall.

---
Changes since v9:
- Recast cover letter: this is a clean-up series, not a
  performance series (Jakub, Sabrina)
- Rephrase subject to describe the refactor (Jakub)
- Split 2/5 into two patches separating the do/while
  loop-structure cleanup from the partial-consume fix (Sabrina)
- Continue the loop after a partial consume to match
  __tcp_read_sock() semantics, instead of exiting (Jakub)
- Drop kdoc on the internal function and rename
  tls_strp_msg_release() to tls_strp_msg_consume() (Jakub)
- Drop kdoc on tls_strp_check_rcv() and un-wrap the "Defer
  notification" comment (Jakub)
- Rename tls_strp_check_rcv() parameter wake to announce, and
  tls_rx_msg_ready() to tls_rx_msg_maybe_announce() (Jakub)
- Drop tls_rx_handoff(); fold the per-record path back into
  tls_rx_rec_done() and fire the deferred announce from
  tls_rx_reader_release() (Jakub)
- New patch: Preserve sk_err across recvmsg() when data has
  been copied, so a connection abort during sk_flush_backlog()
  surfaces on the next read instead of vanishing when the
  caller returns the bytes already accumulated

Changes since v8:
- Address review comments from sashiko
  - Patch 2: Requeue partially consumed skb to prevent leak
  - Patch 5: Re-check sk_err so RST during flush surfaces as
    -ECONNRESET instead of EOF
- Address review comments from gpt-5.5
  - Patch 4: Restore msg_ready early-return in tls_strp_check_rcv()
    so the queued strp_work doesn't double-wake the consumer
  - Patch 4: Add tls_strparser msg_announced bit so the recvmsg
    exit-point handoff doesn't re-fire saved_data_ready() for a
    record BH or the worker already announced (rx_list-only drain
    path)

Changes since v7:
- Rebased on net-next (v7.1-rc1)

Changes since v6:
- Rebased on net-next, v5's 1/6 was merged upstream

Changes since v5:
- Patch 6: Set released = true when sk_flush_backlog() returns
  true, so tls_strp_msg_load() knows the socket lock was
  released (Sabrina)
- Patch 6: Drop Fixes tag; submit bug fix separately via net
  if warranted (Sabrina)
- Patch 6: Note redundant flush on cold path in commit message
  (Sabrina)

Changes since v4:
- Drop batch async decryption and submit/deliver restructure:
  async_capable is always false for TLS 1.3, so the new code
  was unreachable for NFS and NVMe/TCP
- Purge async_hold directly in tls_decrypt_async_wait() and drop
  the tls_decrypt_async_drain() wrapper
- Merge tls_strp_check_rcv_quiet() into tls_strp_check_rcv() with
  a bool wake parameter; fix lost wakeup on the recvmsg exit path

Changes since v3:
- Clarify why tls_decrypt_async_drain() is separate from _wait()
- Fold tls_err_abort() into tls_rx_one_record(), drop tls_rx_decrypt_record()
- Move backlog flush into tls_rx_rec_wait() so all RX paths benefit

Changes since v2:
- Fix short read self tests

Changes since v1:
- Add C11 reference
- Extend data_ready reduction to recvmsg and splice
- Restructure read_sock and recvmsg using shared helpers

---
Chuck Lever (7):
      tls: Move decrypt-failure abort into tls_rx_one_record()
      tls: Avoid evaluating freed skb in tls_sw_read_sock() loop
      tls: Re-present partially-consumed records in tls_sw_read_sock()
      tls: Factor tls_strp_msg_consume() from tls_strp_msg_done()
      tls: Suppress spurious saved_data_ready on all receive paths
      tls: Flush backlog before waiting for a new record
      tls: Preserve sk_err across recvmsg() when data has been copied

 include/net/tls.h  |   5 +++
 net/tls/tls.h      |   6 ++--
 net/tls/tls_main.c |   2 +-
 net/tls/tls_strp.c |  26 +++++++++-----
 net/tls/tls_sw.c   | 103 ++++++++++++++++++++++++++++++++++++++++-------------
 5 files changed, 105 insertions(+), 37 deletions(-)
---
base-commit: 63751099502d10f0aa6bb35273e56c5800cc4e3a
change-id: 20260317-tls-read-sock-a0022c9df265

Best regards,
--  
Chuck Lever <chuck.lever@oracle.com>