CVE-2026-52948
Description
In the Linux kernel, the following vulnerability has been resolved: i2c: dev: prevent integer overflow in I2C_TIMEOUT ioctl While fuzzing with Syzkaller, a persistent `schedule_timeout: wrong timeout value` warning was observed, accompanied by SMBus controller state machine corruption. The I2C_TIMEOUT ioctl accepts a user-provided timeout in multiples of 10 ms. The user argument is checked against INT_MAX, but it is subsequently multiplied by 10 before being passed to msecs_to_jiffies(). A malicious user can pass a large value (e.g., 429496729) that passes the `arg > INT_MAX` check but overflows when multiplied by 10. This results in a truncated 32-bit unsigned value that bypasses the internal `(int)m < 0` check in `msecs_to_jiffies()`. The truncated value is then assigned to `client->adapter->timeout` (a signed 32-bit int), which is reinterpreted as a negative number. When passed to wait_for_completion_timeout(), this negative value undergoes sign extension to a 64-bit unsigned long, triggering the `schedule_timeout` warning and causing premature returns. This leaves the SMBus state machine in an unrecoverable state, constituting a local Denial of Service (DoS). Fix this by bounding the user argument to `INT_MAX / 10`. [wsa: move the comment as well]
References
- https://git.kernel.org/stable/c/0b88ecfbc9dc33b4db8836c37b50cf174e6c0691
- https://git.kernel.org/stable/c/4576621dc6577f21a032acfd16c3ad61907a5ea7
- https://git.kernel.org/stable/c/617eb7c0961a8dfcfc811844a6396e406b2923ea
- https://git.kernel.org/stable/c/943e318eedbeaeea08ece3f5dd44c982f4ed2ef5
- https://git.kernel.org/stable/c/aa6ef734016912653a909477fb30aeb66c98b3a2