Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync

Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync

Fixes the following trace where hci_acl_create_conn_sync attempts to
call hci_abort_conn_sync after timeout:

BUG: KASAN: slab-use-after-free in hci_abort_conn_sync
(net/bluetooth/hci_sync.c:5439)
Read of size 2 at addr ffff88800322c032 by task kworker/u3:2/36

Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-1.fc38
04/01/2014
Workqueue: hci0 hci_cmd_sync_work
Call Trace:
<TASK>
dump_stack_lvl (./arch/x86/include/asm/irqflags.h:26
./arch/x86/include/asm/irqflags.h:67 ./arch/x86/include/asm/irqflags.h:127
lib/dump_stack.c:107)
print_report (mm/kasan/report.c:378 mm/kasan/report.c:488)
? preempt_count_sub (kernel/sched/core.c:5889)
? __virt_addr_valid (./arch/x86/include/asm/preempt.h:103 (discriminator 1)
./include/linux/rcupdate.h:865 (discriminator 1)
./include/linux/mmzone.h:2026 (discriminator 1)
arch/x86/mm/physaddr.c:65 (discriminator 1))
? hci_abort_conn_sync (net/bluetooth/hci_sync.c:5439)
kasan_report (mm/kasan/report.c:603)
? hci_abort_conn_sync (net/bluetooth/hci_sync.c:5439)
hci_abort_conn_sync (net/bluetooth/hci_sync.c:5439)
? __pfx_hci_abort_conn_sync (net/bluetooth/hci_sync.c:5433)
hci_acl_create_conn_sync (net/bluetooth/hci_sync.c:6681)

Fixes: 45340097ce6e ("Bluetooth: hci_conn: Only do ACL connections sequentially")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>