Use After Free Affecting kernel-64k-debug-devel package, versions *

Note: Versions mentioned in the description apply only to the upstream kernel-64k-debug-devel package and not the kernel-64k-debug-devel package as distributed by RHEL. See How to fix? for RHEL:9 relevant fixed versions and status.

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

Bluetooth: hci_conn: Fix UAF in hci_enhanced_setup_sync

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

• https://access.redhat.com/security/cve/CVE-2024-50029
• https://git.kernel.org/stable/c/18fd04ad856df07733f5bb07e7f7168e7443d393
• https://git.kernel.org/stable/c/867639300759e3e1c5b1e1a5ff89231f263a32a7
• https://git.kernel.org/stable/c/98ccd44002d88cbf4edfc4480df532a3da5a013e