CVE-2023-53235
What it is
In the Linux kernel, the following vulnerability has been resolved: drm/tests: helpers: Avoid a driver uaf when using __drm_kunit_helper_alloc_drm_device() the driver may be dereferenced by device-managed resources up until the device is freed, which is typically later than the kunit-managed resource code frees it. Fix this by simply make the driver device-managed as well. In short, the sequence leading to the UAF is as follows: INIT: Code allocates a struct device as a kunit-managed resource. Code allocates a drm driver as a kunit-managed resource. Code allocates a drm device as a device-managed resource. EXIT: Kunit resource cleanup frees the drm driver Kunit resource cleanup puts the struct device, which starts a device-managed resource cleanup device-managed cleanup calls drm_dev_put() drm_dev_put() dereferences the (now freed) drm driver -> Boom. Related KASAN message: [55272.551542] ================================================================== [55272.551551] BUG: KASAN: slab-use-after-free in drm_dev_put.part.0+0xd4/0xe0 [drm] [55272.551603] Read of size 8 at addr ffff888127502828 by task kunit_try_catch/10353 [55272.551612] CPU: 4 PID: 10353 Comm: kunit_try_catch Tainted: G U N 6.5.0-rc7+ #155 [55272.551620] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 0403 01/26/2021 [55272.551626] Call Trace: [55272.551629] <TASK> [55272.551633] dump_stack_lvl+0x57/0x90 [55272.551639] print_report+0xcf/0x630 [55272.551645] ? _raw_spin_lock_irqsave+0x5f/0x70 [55272.551652] ? drm_dev_put.part.0+0xd4/0xe0 [drm] [55272.551694] kasan_report+0xd7/0x110 [55272.551699] ? drm_dev_put.part.0+0xd4/0xe0 [drm] [55272.551742] drm_dev_put.part.0+0xd4/0xe0 [drm] [55272.551783] devres_release_all+0x15d/0x1f0 [55272.551790] ? __pfx_devres_release_all+0x10/0x10 [55272.551797] device_unbind_cleanup+0x16/0x1a0 [55272.551802] device_release_driver_internal+0x3e5/0x540 [55272.551808] ? kobject_put+0x5d/0x4b0 [55272.551814] bus_remove_device+0x1f1/0x3f0 [55272.551819] device_del+0x342/0x910 [55272.551826] ? __pfx_device_del+0x10/0x10 [55272.551830] ? lock_release+0x339/0x5e0 [55272.551836] ? kunit_remove_resource+0x128/0x290 [kunit] [55272.551845] ? __pfx_lock_release+0x10/0x10 [55272.551851] platform_device_del.part.0+0x1f/0x1e0 [55272.551856] ? _raw_spin_unlock_irqrestore+0x30/0x60 [55272.551863] kunit_remove_resource+0x195/0x290 [kunit] [55272.551871] ? _raw_spin_unlock_irqrestore+0x30/0x60 [55272.551877] kunit_cleanup+0x78/0x120 [kunit] [55272.551885] ? __kthread_parkme+0xc1/0x1f0 [55272.551891] ? __pfx_kunit_try_run_case_cleanup+0x10/0x10 [kunit] [55272.551900] ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10 [kunit] [55272.551909] kunit_generic_run_threadfn_adapter+0x4a/0x90 [kunit] [55272.551919] kthread+0x2e7/0x3c0 [55272.551924] ? __pfx_kthread+0x10/0x10 [55272.551929] ret_from_fork+0x2d/0x70 [55272.551935] ? __pfx_kthread+0x10/0x10 [55272.551940] ret_from_fork_asm+0x1b/0x30 [55272.551948] </TASK> [55272.551953] Allocated by task 10351: [55272.551956] kasan_save_stack+0x1c/0x40 [55272.551962] kasan_set_track+0x21/0x30 [55272.551966] __kasan_kmalloc+0x8b/0x90 [55272.551970] __kmalloc+0x5e/0x160 [55272.551976] kunit_kmalloc_array+0x1c/0x50 [kunit] [55272.551984] drm_exec_test_init+0xfa/0x2c0 [drm_exec_test] [55272.551991] kunit_try_run_case+0xdd/0x250 [kunit] [55272.551999] kunit_generic_run_threadfn_adapter+0x4a/0x90 [kunit] [55272.552008] kthread+0x2e7/0x3c0 [55272.552012] ret_from_fork+0x2d/0x70 [55272.552017] ret_from_fork_asm+0x1b/0x30 [55272.552024] Freed by task 10353: [55272.552027] kasan_save_stack+0x1c/0x40 [55272.552032] kasan_set_track+0x21/0x30 [55272.552036] kasan_save_free_info+0x27/0x40 [55272.552041] __kasan_slab_free+0x106/0x180 [55272.552046] slab_free_freelist_hook+0xb3/0x160 [55272.552051] __kmem_cache_free+0xb2/0x290 [55272.552056] kunit_remove_resource+0x195/0x290 [kunit] [55272.552064] kunit_cleanup+0x7 ---truncated---
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Modified
Affected
- Linux Kernel < 6.5.5
- Linux Kernel 6.6
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2023-53235.md and follow it. Check whether this project is affected by CVE-2023-53235. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/139a27854bf5ce93ff9805f9f7683b88c13074dc
- https://git.kernel.org/stable/c/c9d8be0e533738b744abb669263c4750d4830009