fkie_cve-2022-50563
Vulnerability from fkie_nvd
Published
2025-10-22 14:15
Modified
2025-10-22 21:12
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
dm thin: Fix UAF in run_timer_softirq()
When dm_resume() and dm_destroy() are concurrent, it will
lead to UAF, as follows:
BUG: KASAN: use-after-free in __run_timers+0x173/0x710
Write of size 8 at addr ffff88816d9490f0 by task swapper/0/0
<snip>
Call Trace:
<IRQ>
dump_stack_lvl+0x73/0x9f
print_report.cold+0x132/0xaa2
_raw_spin_lock_irqsave+0xcd/0x160
__run_timers+0x173/0x710
kasan_report+0xad/0x110
__run_timers+0x173/0x710
__asan_store8+0x9c/0x140
__run_timers+0x173/0x710
call_timer_fn+0x310/0x310
pvclock_clocksource_read+0xfa/0x250
kvm_clock_read+0x2c/0x70
kvm_clock_get_cycles+0xd/0x20
ktime_get+0x5c/0x110
lapic_next_event+0x38/0x50
clockevents_program_event+0xf1/0x1e0
run_timer_softirq+0x49/0x90
__do_softirq+0x16e/0x62c
__irq_exit_rcu+0x1fa/0x270
irq_exit_rcu+0x12/0x20
sysvec_apic_timer_interrupt+0x8e/0xc0
One of the concurrency UAF can be shown as below:
use free
do_resume |
__find_device_hash_cell |
dm_get |
atomic_inc(&md->holders) |
| dm_destroy
| __dm_destroy
| if (!dm_suspended_md(md))
| atomic_read(&md->holders)
| msleep(1)
dm_resume |
__dm_resume |
dm_table_resume_targets |
pool_resume |
do_waker #add delay work |
dm_put |
atomic_dec(&md->holders) |
| dm_table_destroy
| pool_dtr
| __pool_dec
| __pool_destroy
| destroy_workqueue
| kfree(pool) # free pool
time out
__do_softirq
run_timer_softirq # pool has already been freed
This can be easily reproduced using:
1. create thin-pool
2. dmsetup suspend pool
3. dmsetup resume pool
4. dmsetup remove_all # Concurrent with 3
The root cause of this UAF bug is that dm_resume() adds timer after
dm_destroy() skips cancelling the timer because of suspend status.
After timeout, it will call run_timer_softirq(), however pool has
already been freed. The concurrency UAF bug will happen.
Therefore, cancelling timer again in __pool_destroy().
References
Impacted products
| Vendor | Product | Version |
|---|
{
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm thin: Fix UAF in run_timer_softirq()\n\nWhen dm_resume() and dm_destroy() are concurrent, it will\nlead to UAF, as follows:\n\n BUG: KASAN: use-after-free in __run_timers+0x173/0x710\n Write of size 8 at addr ffff88816d9490f0 by task swapper/0/0\n\u003csnip\u003e\n Call Trace:\n \u003cIRQ\u003e\n dump_stack_lvl+0x73/0x9f\n print_report.cold+0x132/0xaa2\n _raw_spin_lock_irqsave+0xcd/0x160\n __run_timers+0x173/0x710\n kasan_report+0xad/0x110\n __run_timers+0x173/0x710\n __asan_store8+0x9c/0x140\n __run_timers+0x173/0x710\n call_timer_fn+0x310/0x310\n pvclock_clocksource_read+0xfa/0x250\n kvm_clock_read+0x2c/0x70\n kvm_clock_get_cycles+0xd/0x20\n ktime_get+0x5c/0x110\n lapic_next_event+0x38/0x50\n clockevents_program_event+0xf1/0x1e0\n run_timer_softirq+0x49/0x90\n __do_softirq+0x16e/0x62c\n __irq_exit_rcu+0x1fa/0x270\n irq_exit_rcu+0x12/0x20\n sysvec_apic_timer_interrupt+0x8e/0xc0\n\nOne of the concurrency UAF can be shown as below:\n\n use free\ndo_resume |\n __find_device_hash_cell |\n dm_get |\n atomic_inc(\u0026md-\u003eholders) |\n | dm_destroy\n | __dm_destroy\n | if (!dm_suspended_md(md))\n | atomic_read(\u0026md-\u003eholders)\n | msleep(1)\n dm_resume |\n __dm_resume |\n dm_table_resume_targets |\n pool_resume |\n do_waker #add delay work |\n dm_put |\n atomic_dec(\u0026md-\u003eholders) |\n | dm_table_destroy\n | pool_dtr\n | __pool_dec\n | __pool_destroy\n | destroy_workqueue\n | kfree(pool) # free pool\n time out\n__do_softirq\n run_timer_softirq # pool has already been freed\n\nThis can be easily reproduced using:\n 1. create thin-pool\n 2. dmsetup suspend pool\n 3. dmsetup resume pool\n 4. dmsetup remove_all # Concurrent with 3\n\nThe root cause of this UAF bug is that dm_resume() adds timer after\ndm_destroy() skips cancelling the timer because of suspend status.\nAfter timeout, it will call run_timer_softirq(), however pool has\nalready been freed. The concurrency UAF bug will happen.\n\nTherefore, cancelling timer again in __pool_destroy()."
}
],
"id": "CVE-2022-50563",
"lastModified": "2025-10-22T21:12:48.953",
"metrics": {},
"published": "2025-10-22T14:15:41.067",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/34cd15d83b7206188d440b29b68084fcafde9395"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/34fe9c2251f19786a6689149a6212c6c0de1d63b"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/550a4fac7ecfee5bac6a0dd772456ca62fb72f46"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/7ae6aa649394e1e7f6dafb55ce0d578c0572a280"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/7ee059d06a5d3c15465959e0472993e80fbe4e81"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/88430ebcbc0ec637b710b947738839848c20feff"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/94e231c9d6f2648d2f1f68e7f476e050ee0a6159"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/d9971fa4d8bde63d49c743c1b32d12fbbd3a30bd"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/e8b8e0d2bbf7d1172c4f435621418e29ee408d46"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Awaiting Analysis"
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…