From: Mingyu Wang <25181214217@stu.xidian.edu.cn> stable inclusion from stable-v6.6.143 commit aa6ef734016912653a909477fb30aeb66c98b3a2 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/15650 CVE: CVE-2026-52948 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 617eb7c0961a8dfcfc811844a6396e406b2923ea upstream. 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`. Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn> [wsa: move the comment as well] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yin Tirui <yintirui@huawei.com> --- drivers/i2c/i2c-dev.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c index 7d337380a05d..2ee07fc675d6 100644 --- a/drivers/i2c/i2c-dev.c +++ b/drivers/i2c/i2c-dev.c @@ -476,12 +476,13 @@ static long i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) client->adapter->retries = arg; break; case I2C_TIMEOUT: - if (arg > INT_MAX) + /* + * For historical reasons, user-space sets the timeout value in + * units of 10 ms. + */ + if (arg > INT_MAX / 10) return -EINVAL; - /* For historical reasons, user-space sets the timeout - * value in units of 10 ms. - */ client->adapter->timeout = msecs_to_jiffies(arg * 10); break; default: -- 2.43.0