From: Aaron Thompson dev@aaront.org
If iso_init() has been called, iso_exit() must be called on module unload. Without that, the struct proto that iso_init() registered with proto_register() becomes invalid, which could cause unpredictable problems later. In my case, with CONFIG_LIST_HARDENED and CONFIG_BUG_ON_DATA_CORRUPTION enabled, loading the module again usually triggers this BUG():
list_add corruption. next->prev should be prev (ffffffffb5355fd0), but was 0000000000000068. (next=ffffffffc0a010d0). ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:29! Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 1 PID: 4159 Comm: modprobe Not tainted 6.10.11-4+bt2-ao-desktop #1 RIP: 0010:__list_add_valid_or_report+0x61/0xa0 ... __list_add_valid_or_report+0x61/0xa0 proto_register+0x299/0x320 hci_sock_init+0x16/0xc0 [bluetooth] bt_init+0x68/0xd0 [bluetooth] __pfx_bt_init+0x10/0x10 [bluetooth] do_one_initcall+0x80/0x2f0 do_init_module+0x8b/0x230 __do_sys_init_module+0x15f/0x190 do_syscall_64+0x68/0x110 ...
Cc: stable@vger.kernel.org Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Signed-off-by: Aaron Thompson dev@aaront.org --- net/bluetooth/mgmt.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index e4f564d6f6fb..78a164fab3e1 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -10487,6 +10487,7 @@ int mgmt_init(void)
void mgmt_exit(void) { + iso_exit(); hci_mgmt_chan_unregister(&chan); }