From: Luiz Augusto von Dentz luiz.von.dentz@intel.com

commit 18fd04ad856df07733f5bb07e7f7168e7443d393 upstream.

This checks if the ACL connection remains valid as it could be destroyed while hci_enhanced_setup_sync is pending on cmd_sync leading to the following trace:

BUG: KASAN: slab-use-after-free in hci_enhanced_setup_sync+0x91b/0xa60 Read of size 1 at addr ffff888002328ffd by task kworker/u5:2/37

CPU: 0 UID: 0 PID: 37 Comm: kworker/u5:2 Not tainted 6.11.0-rc6-01300-g810be445d8d6 #7099 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014 Workqueue: hci0 hci_cmd_sync_work Call Trace: <TASK> dump_stack_lvl+0x5d/0x80 ? hci_enhanced_setup_sync+0x91b/0xa60 print_report+0x152/0x4c0 ? hci_enhanced_setup_sync+0x91b/0xa60 ? __virt_addr_valid+0x1fa/0x420 ? hci_enhanced_setup_sync+0x91b/0xa60 kasan_report+0xda/0x1b0 ? hci_enhanced_setup_sync+0x91b/0xa60 hci_enhanced_setup_sync+0x91b/0xa60 ? __pfx_hci_enhanced_setup_sync+0x10/0x10 ? __pfx___mutex_lock+0x10/0x10 hci_cmd_sync_work+0x1c2/0x330 process_one_work+0x7d9/0x1360 ? __pfx_lock_acquire+0x10/0x10 ? __pfx_process_one_work+0x10/0x10 ? assign_work+0x167/0x240 worker_thread+0x5b7/0xf60 ? __kthread_parkme+0xac/0x1c0 ? __pfx_worker_thread+0x10/0x10 ? __pfx_worker_thread+0x10/0x10 kthread+0x293/0x360 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2f/0x70 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK>

Allocated by task 34: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x8f/0xa0 __hci_conn_add+0x187/0x17d0 hci_connect_sco+0x2e1/0xb90 sco_sock_connect+0x2a2/0xb80 __sys_connect+0x227/0x2a0 __x64_sys_connect+0x6d/0xb0 do_syscall_64+0x71/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Freed by task 37: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x101/0x160 kfree+0xd0/0x250 device_release+0x9a/0x210 kobject_put+0x151/0x280 hci_conn_del+0x448/0xbf0 hci_abort_conn_sync+0x46f/0x980 hci_cmd_sync_work+0x1c2/0x330 process_one_work+0x7d9/0x1360 worker_thread+0x5b7/0xf60 kthread+0x293/0x360 ret_from_fork+0x2f/0x70 ret_from_fork_asm+0x1a/0x30

Cc: stable@vger.kernel.org Fixes: e07a06b4eb41 ("Bluetooth: Convert SCO configure_datapath to hci_sync") Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com [kovalev: inline `hci_conn_valid()` functionality directly into `hci_enhanced_setup_sync()` to avoid dependencies during backporting.] Link: https://lore.kernel.org/all/2024101446-approve-rants-581d@gregkh/ Signed-off-by: Vasiliy Kovalev kovalev@altlinux.org --- Backport to fix CVE-2024-50029 Link: https://www.cve.org/CVERecord/?id=CVE-2024-50029 --- net/bluetooth/hci_conn.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)

diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index 49b9dd21b73ea6..3906324b99d41a 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -390,9 +390,22 @@ static int hci_enhanced_setup_sync(struct hci_dev *hdev, void *data) __u16 handle = conn_handle->handle; struct hci_cp_enhanced_setup_sync_conn cp; const struct sco_param *param; + struct hci_conn_hash *hdev_conn_hash = &hdev->conn_hash; + struct hci_conn *hdev_conn;

kfree(conn_handle);

+ rcu_read_lock(); + list_for_each_entry_rcu(hdev_conn, &hdev_conn_hash->list, list) { + if (hdev_conn == conn) { + rcu_read_unlock(); + goto conn_valid; + } + } + rcu_read_unlock(); + return -ECANCELED; + +conn_valid: bt_dev_dbg(hdev, "hcon %p", conn);

configure_datapath_sync(hdev, &conn->codec);