[0/3] Bluetooth: ISO-related concurrency fixes

Message

Pauli Virtanen June 8, 2023, 9:06 p.m. UTC

This series addresses some concurrency issues (NULL / GPF) in ISO
sockets or related.

These were found while testing patches that make hci_le_set_cig_params
check the validity of the configuration and return false if incorrect.
This causes dropping of hci_conn just created, which apparently makes
hitting race conditions easier.

The test setup was primitive

while true; do bluetoothctl power on; sleep 12; bluetoothctl power off; sleep 1.5; bluetoothctl power off; sleep 2.5; done;
while true; do sudo systemctl restart bluetooth; sleep 110; done
while true; do systemctl --user restart pipewire wireplumber pipewire-pulse; sleep 91; done
while true; do paplay sample.flac & sleep 2; kill %1; sleep 0.7; done

and equivalent operations manually, on VM + connect to TWS earbuds. This
eventually hit the NULL / GFP errors here, but they are hard to
reproduce aside from the first one that appears in iso-tester.

This also produces a few other types of crashes / KASAN errors, but not
addressed here.

Pauli Virtanen (3):
  Bluetooth: hci_sync: iterate over hci_conn_params safely
  Bluetooth: hci_event: call ISO disconnect callback before deleting
    conn
  Bluetooth: ISO: fix iso_conn related locking and validity issues

 include/net/bluetooth/hci_core.h |  1 +
 net/bluetooth/hci_event.c        |  6 +++
 net/bluetooth/hci_sync.c         | 81 ++++++++++++++++++++++++++++----
 net/bluetooth/iso.c              | 53 ++++++++++++---------
 4 files changed, 111 insertions(+), 30 deletions(-)