Description
In the Linux kernel, the following vulnerability has been resolved:
rtc: ac100: Fix clock provider use-after-free on probe failure
ac100_rtc_register_clks() registers the RTC-32k clock with
clk_hw_register_fixed_rate() and the clock provider with
of_clk_add_hw_provider(). Neither is device managed, and both are
released only from ac100_rtc_remove(). The driver core does not call
remove() when probe() fails: really_probe() reaches probe_failed below
the device_remove() call and goes straight to releasing the device's
managed resources.
ac100_rtc_probe() ends with
return devm_rtc_register_device(chip->rtc);
so if that fails after the clocks have been registered, the provider is
left on the global of_clk_providers list holding chip->clk_data, which
was allocated with devm_kzalloc() and is freed while probe() unwinds. A
later lookup on this device tree node then reads freed memory in
of_clk_hw_onecell_get(). Consumers that do exactly that exist in tree:
the wifi power sequence nodes on sun8i-a83t-bananapi-m3 and
sun8i-a83t-cubietruck-plus take <&ac100_rtc 1>, and the sun9i-a80 boards
route osc32k through <&ac100_rtc 0>. The window is narrow, as
devm_rtc_register_device() can only fail with -ENOMEM here, but the
provider is left dangling whenever it does.
The RTC-32k clock is leaked on the same path. Since clk_core_lookup()
searches a global list that is not scoped per device, __clk_register()
rejects the duplicate name with -EEXIST, so the leak also makes a later
probe of the same device fail.
The error path that returns -EINVAL when the ADDA 4M parent clock cannot
be found leaks the RTC-32k clock in the same way. No provider has been
registered at that point, so that one is a leak rather than a
use-after-free.
Register both with devm_clk_hw_register_fixed_rate() and
devm_of_clk_add_hw_provider() so that they are released whenever the
device goes away, on a failed probe as well as on unbind. Devres
releases in reverse order of acquisition, so the provider is removed
before chip->clk_data is freed, and the clkout children are now
unregistered before their parent rather than after it.
ac100_rtc_unregister_clks() and the remove callback then have nothing
left to do and are removed.
rtc: ac100: Fix clock provider use-after-free on probe failure
ac100_rtc_register_clks() registers the RTC-32k clock with
clk_hw_register_fixed_rate() and the clock provider with
of_clk_add_hw_provider(). Neither is device managed, and both are
released only from ac100_rtc_remove(). The driver core does not call
remove() when probe() fails: really_probe() reaches probe_failed below
the device_remove() call and goes straight to releasing the device's
managed resources.
ac100_rtc_probe() ends with
return devm_rtc_register_device(chip->rtc);
so if that fails after the clocks have been registered, the provider is
left on the global of_clk_providers list holding chip->clk_data, which
was allocated with devm_kzalloc() and is freed while probe() unwinds. A
later lookup on this device tree node then reads freed memory in
of_clk_hw_onecell_get(). Consumers that do exactly that exist in tree:
the wifi power sequence nodes on sun8i-a83t-bananapi-m3 and
sun8i-a83t-cubietruck-plus take <&ac100_rtc 1>, and the sun9i-a80 boards
route osc32k through <&ac100_rtc 0>. The window is narrow, as
devm_rtc_register_device() can only fail with -ENOMEM here, but the
provider is left dangling whenever it does.
The RTC-32k clock is leaked on the same path. Since clk_core_lookup()
searches a global list that is not scoped per device, __clk_register()
rejects the duplicate name with -EEXIST, so the leak also makes a later
probe of the same device fail.
The error path that returns -EINVAL when the ADDA 4M parent clock cannot
be found leaks the RTC-32k clock in the same way. No provider has been
registered at that point, so that one is a leak rather than a
use-after-free.
Register both with devm_clk_hw_register_fixed_rate() and
devm_of_clk_add_hw_provider() so that they are released whenever the
device goes away, on a failed probe as well as on unbind. Devres
releases in reverse order of acquisition, so the provider is removed
before chip->clk_data is freed, and the clkout children are now
unregistered before their parent rather than after it.
ac100_rtc_unregister_clks() and the remove callback then have nothing
left to do and are removed.
Published:
2026-10-18
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
No analysis available yet.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
|||||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No remediation available yet.
Tracking
Sign in to view the affected projects.
Advisories
No advisories yet.
References
History
Sun, 18 Oct 2026 16:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: rtc: ac100: Fix clock provider use-after-free on probe failure ac100_rtc_register_clks() registers the RTC-32k clock with clk_hw_register_fixed_rate() and the clock provider with of_clk_add_hw_provider(). Neither is device managed, and both are released only from ac100_rtc_remove(). The driver core does not call remove() when probe() fails: really_probe() reaches probe_failed below the device_remove() call and goes straight to releasing the device's managed resources. ac100_rtc_probe() ends with return devm_rtc_register_device(chip->rtc); so if that fails after the clocks have been registered, the provider is left on the global of_clk_providers list holding chip->clk_data, which was allocated with devm_kzalloc() and is freed while probe() unwinds. A later lookup on this device tree node then reads freed memory in of_clk_hw_onecell_get(). Consumers that do exactly that exist in tree: the wifi power sequence nodes on sun8i-a83t-bananapi-m3 and sun8i-a83t-cubietruck-plus take <&ac100_rtc 1>, and the sun9i-a80 boards route osc32k through <&ac100_rtc 0>. The window is narrow, as devm_rtc_register_device() can only fail with -ENOMEM here, but the provider is left dangling whenever it does. The RTC-32k clock is leaked on the same path. Since clk_core_lookup() searches a global list that is not scoped per device, __clk_register() rejects the duplicate name with -EEXIST, so the leak also makes a later probe of the same device fail. The error path that returns -EINVAL when the ADDA 4M parent clock cannot be found leaks the RTC-32k clock in the same way. No provider has been registered at that point, so that one is a leak rather than a use-after-free. Register both with devm_clk_hw_register_fixed_rate() and devm_of_clk_add_hw_provider() so that they are released whenever the device goes away, on a failed probe as well as on unbind. Devres releases in reverse order of acquisition, so the provider is removed before chip->clk_data is freed, and the clkout children are now unregistered before their parent rather than after it. ac100_rtc_unregister_clks() and the remove callback then have nothing left to do and are removed. | |
| Title | rtc: ac100: Fix clock provider use-after-free on probe failure | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-18T15:49:19.709Z
Reserved: 2026-09-25T10:25:14.372Z
Link: CVE-2026-98826
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-18T16:17:36.823
Modified: 2026-10-18T16:17:36.823
Link: CVE-2026-98826
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.