CVE-2024-50078

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: Call iso_exit() on module unload

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 ...

The bug happens only when admin unloads and then loads again Bluetooth kernel module, so impact is limited.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this issue, prevent module bluetooth from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.