The 11/01/2022 12:19, David Laight wrote: > From: 'Szabolcs Nagy' <szabolcs.nagy@xxxxxxx> > > SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd, unsigned long, arg) > > { > > That is just a wrapper and calls do_fcntl(). > which needs changing to be add: > arg &= ~0U; > before the switch(cmd) { this makes sense. i thought previously you meant masking in userspace. although if you mask there then many linux internal apis could use int instead of long arg. do you want me to post a patch? (i'm not a kernel developer)