Re: [PATCH net] ptp: Ensure info->enable callback is always set

Andrew Lunn
2025-01-22T20:16:12Z

On Wed, Jan 22, 2025 at 07:39:31PM +0100, Thomas Weißschuh wrote:
> The ioctl and sysfs handlers unconditionally call the ->enable callback.
> Not all drivers implement that callback, leading to NULL dereferences.
> Example of affected drivers: ptp_s390.c, ptp_vclock.c and ptp_mock.c.

> + if (!ptp->info->enable)
> + ptp->info->enable = ptp_enable;

Is it possible that a driver has defined info as a const, and placed
it into read only memory? It is generally good practice to make
structures of ops read only to prevent some forms of attack.

Andrew