[linux-morello] Re: [PATCH v2 1/5] fcntl: Cast commands with int args explicitly

On Fri, Apr 14, 2023 at 04:24:55PM +0100, Luca Vizzarro wrote:

void __user *argp = (void __user *)arg;

• int argi = (int)arg;

Strictly speaking, conversion from unsigned long to int is an undefined behaviour, unless the value fits into the range representable by int ;-)

case F_SETFD: err = 0;

• set_close_on_exec(fd, arg & FD_CLOEXEC);
  

• set_close_on_exec(fd, argi & FD_CLOEXEC);
  

Why?

case F_SETSIG: /* arg == 0 restores default behaviour. */

• if (!valid_signal(arg)) {
  

• if (!valid_signal(argi)) {
  

Why???

	break;
}
err = 0;

• filp->f_owner.signum = arg;
  

• filp->f_owner.signum = argi;
  

  break;

These two are clearly bogus and I'd like to see more details on the series rationale, please.