CVE-2026-52948

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]