CVE-2023-52707 Affecting kernel-livepatch-5_3_18-150200_24_197-default package, versions <1-150200.5.3.1


Severity

Recommended
0.0
high
0
10

Based on SUSE Linux Enterprise Server security rating.

Threat Intelligence

EPSS
0.05% (18th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-SLES152-KERNELLIVEPATCH531815020024197DEFAULT-7436575
  • published10 Jul 2024
  • disclosed9 Jul 2024

Introduced: 9 Jul 2024

CVE-2023-52707  (opens in a new tab)

How to fix?

Upgrade SLES:15.2 kernel-livepatch-5_3_18-150200_24_197-default to version 1-150200.5.3.1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-livepatch-5_3_18-150200_24_197-default package and not the kernel-livepatch-5_3_18-150200_24_197-default package as distributed by SLES. See How to fix? for SLES:15.2 relevant fixed versions and status.

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

sched/psi: Fix use-after-free in ep_remove_wait_queue()

If a non-root cgroup gets removed when there is a thread that registered trigger and is polling on a pressure file within the cgroup, the polling waitqueue gets freed in the following path:

do_rmdir cgroup_rmdir kernfs_drain_open_files cgroup_file_release cgroup_pressure_release psi_trigger_destroy

However, the polling thread still has a reference to the pressure file and will access the freed waitqueue when the file is closed or upon exit:

fput ep_eventpoll_release ep_free ep_remove_wait_queue remove_wait_queue

This results in use-after-free as pasted below.

The fundamental problem here is that cgroup_file_release() (and consequently waitqueue's lifetime) is not tied to the file's real lifetime. Using wake_up_pollfree() here might be less than ideal, but it is in line with the comment at commit 42288cb44c4b ("wait: add wake_up_pollfree()") since the waitqueue's lifetime is not tied to file's one and can be considered as another special case. While this would be fixable by somehow making cgroup_file_release() be tied to the fput(), it would require sizable refactoring at cgroups or higher layer which might be more justifiable if we identify more cases like this.

BUG: KASAN: use-after-free in _raw_spin_lock_irqsave+0x60/0xc0 Write of size 4 at addr ffff88810e625328 by task a.out/4404

CPU: 19 PID: 4404 Comm: a.out Not tainted 6.2.0-rc6 #38
Hardware name: Amazon EC2 c5a.8xlarge/, BIOS 1.0 10/16/2017
Call Trace:
&lt;TASK&gt;
dump_stack_lvl+0x73/0xa0
print_report+0x16c/0x4e0
kasan_report+0xc3/0xf0
kasan_check_range+0x2d2/0x310
_raw_spin_lock_irqsave+0x60/0xc0
remove_wait_queue+0x1a/0xa0
ep_free+0x12c/0x170
ep_eventpoll_release+0x26/0x30
__fput+0x202/0x400
task_work_run+0x11d/0x170
do_exit+0x495/0x1130
do_group_exit+0x100/0x100
get_signal+0xd67/0xde0
arch_do_signal_or_restart+0x2a/0x2b0
exit_to_user_mode_prepare+0x94/0x100
syscall_exit_to_user_mode+0x20/0x40
do_syscall_64+0x52/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
&lt;/TASK&gt;

Allocated by task 4404:

kasan_set_track+0x3d/0x60
__kasan_kmalloc+0x85/0x90
psi_trigger_create+0x113/0x3e0
pressure_write+0x146/0x2e0
cgroup_file_write+0x11c/0x250
kernfs_fop_write_iter+0x186/0x220
vfs_write+0x3d8/0x5c0
ksys_write+0x90/0x110
do_syscall_64+0x43/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 4407:

kasan_set_track+0x3d/0x60
kasan_save_free_info+0x27/0x40
____kasan_slab_free+0x11d/0x170
slab_free_freelist_hook+0x87/0x150
__kmem_cache_free+0xcb/0x180
psi_trigger_destroy+0x2e8/0x310
cgroup_file_release+0x4f/0xb0
kernfs_drain_open_files+0x165/0x1f0
kernfs_drain+0x162/0x1a0
__kernfs_remove+0x1fb/0x310
kernfs_remove_by_name_ns+0x95/0xe0
cgroup_addrm_files+0x67f/0x700
cgroup_destroy_locked+0x283/0x3c0
cgroup_rmdir+0x29/0x100
kernfs_iop_rmdir+0xd1/0x140
vfs_rmdir+0xfe/0x240
do_rmdir+0x13d/0x280
__x64_sys_rmdir+0x2c/0x30
do_syscall_64+0x43/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd

CVSS Scores

version 3.1