CVE-2022-50370
What it is
In the Linux kernel, the following vulnerability has been resolved: i2c: designware: Fix handling of real but unexpected device interrupts Commit c7b79a752871 ("mfd: intel-lpss: Add Intel Alder Lake PCH-S PCI IDs") caused a regression on certain Gigabyte motherboards for Intel Alder Lake-S where system crashes to NULL pointer dereference in i2c_dw_xfer_msg() when system resumes from S3 sleep state ("deep"). I was able to debug the issue on Gigabyte Z690 AORUS ELITE and made following notes: - Issue happens when resuming from S3 but not when resuming from "s2idle" - PCI device 00:15.0 == i2c_designware.0 is already in D0 state when system enters into pci_pm_resume_noirq() while all other i2c_designware PCI devices are in D3. Devices were runtime suspended and in D3 prior entering into suspend - Interrupt comes after pci_pm_resume_noirq() when device interrupts are re-enabled - According to register dump the interrupt really comes from the i2c_designware.0. Controller is enabled, I2C target address register points to a one detectable I2C device address 0x60 and the DW_IC_RAW_INTR_STAT register START_DET, STOP_DET, ACTIVITY and TX_EMPTY bits are set indicating completed I2C transaction. My guess is that the firmware uses this controller to communicate with an on-board I2C device during resume but does not disable the controller before giving control to an operating system. I was told the UEFI update fixes this but never the less it revealed the driver is not ready to handle TX_EMPTY (or RX_FULL) interrupt when device is supposed to be idle and state variables are not set (especially the dev->msgs pointer which may point to NULL or stale old data). Introduce a new software status flag STATUS_ACTIVE indicating when the controller is active in driver point of view. Now treat all interrupts that occur when is not set as unexpected and mask all interrupts from the controller.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of 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: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-476 · NULL pointer dereference
- Record status
- Modified
Affected
- Linux Kernel < 5.15.75
- Linux Kernel < 5.19.17
- Linux Kernel < 6.0.3
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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-2022-50370.md and follow it. Check whether this project is affected by CVE-2022-50370. 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/301c8f5c32c8fb79c67539bc23972dc3ef48024c
- https://git.kernel.org/stable/c/7fa5304c4b5b425d4a0b3acf10139a7f6108a85f
- https://git.kernel.org/stable/c/a206f7fbe9589c60fafad12884628c909ecb042f
- https://git.kernel.org/stable/c/aa59ac81e859006d3a1df035a19b3f2089110f93