linux/net/tls
Tariq Toukan f08d8c1bb9 net/tls: Fix race in TLS device down flow
Socket destruction flow and tls_device_down function sync against each
other using tls_device_lock and the context refcount, to guarantee the
device resources are freed via tls_dev_del() by the end of
tls_device_down.

In the following unfortunate flow, this won't happen:
- refcount is decreased to zero in tls_device_sk_destruct.
- tls_device_down starts, skips the context as refcount is zero, going
  all the way until it flushes the gc work, and returns without freeing
  the device resources.
- only then, tls_device_queue_ctx_destruction is called, queues the gc
  work and frees the context's device resources.

Solve it by decreasing the refcount in the socket's destruction flow
under the tls_device_lock, for perfect synchronization.  This does not
slow down the common likely destructor flow, in which both the refcount
is decreased and the spinlock is acquired, anyway.

Fixes: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Reviewed-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-18 11:33:07 +01:00
..
Kconfig net/tls: Select SOCK_RX_QUEUE_MAPPING from TLS_DEVICE 2021-02-11 19:08:06 -08:00
Makefile net/tls: add skeleton of MIB statistics 2019-10-05 16:29:00 -07:00
tls_device_fallback.c net/tls: Fix use-after-free after the TLS device goes down and up 2021-06-01 15:58:05 -07:00
tls_device.c net/tls: Fix race in TLS device down flow 2022-07-18 11:33:07 +01:00
tls_main.c net/tls: Check for errors in tls_device_init 2022-07-14 10:12:39 -07:00
tls_proc.c net: fix proc_fs init handling in af_packet and tls 2020-12-14 19:39:30 -08:00
tls_sw.c Revert "tls: rx: move counting TlsDecryptErrors for sync" 2022-07-06 13:10:59 +01:00
tls_toe.c net/tls: rename tls_hw_* functions tls_toe_* 2019-10-04 14:07:07 -07:00
trace.c net/tls: add tracing for device/offload events 2019-10-05 16:29:00 -07:00
trace.h net/tls: add device decrypted trace point 2019-10-05 16:29:00 -07:00