CVE-2024-35997 HID: i2c-hid: remove I2C_HID_READ_PENDING flag to prevent lock-up
A flaw in the Linux kernel's I2C HID driver can cause a system lock-up via an infinite interrupt loop, requiring a kernel patch to resolve.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-35997?
CVE-2024-35997 is a medium-severity denial of service vulnerability in Linux kernel, published on 20 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
HID: i2c-hid: remove I2C_HID_READ_PENDING flag to prevent lock-up
The flag I2C_HID_READ_PENDING is used to serialize I2C operations. However, this is not necessary, because I2C core already has its own locking for that.
More importantly, this flag can cause a lock-up: if the flag is set in i2c_hid_xfer() and an interrupt happens, the interrupt handler (i2c_hid_irq) will check this flag and return immediately without doing anything, then the interrupt handler will be invoked again in an infinite loop.
Since interrupt handler is an RT task, it takes over the CPU and the flag-clearing task never gets scheduled, thus we have a lock-up.
Delete this unnecessary flag.
Weakness: CWE-667
Which versions are affected by CVE-2024-35997?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-35997?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-35997 being exploited?
There is no known exploitation of CVE-2024-35997 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-42181, AZL-42271, BELL-CVE-2024-35997, DEBIAN-CVE-2024-35997, GHSA-23x8-g5mh-phmc, UBUNTU-CVE-2024-35997.