On 2023/12/23 10:23, Paul Moore wrote: >> - /* RED-PEN how should LSM module know it's handling 32bit? */ >> - error = security_file_ioctl(f.file, cmd, arg); >> + error = security_file_ioctl_compat(f.file, cmd, arg); >> if (error) >> goto out; > > This is interesting ... if you look at the normal ioctl() syscall > definition in the kernel you see 'ioctl(unsigned int fd, unsigned int > cmd, unsigned long arg)' and if you look at the compat definition you > see 'ioctl(unsigned int fd, unsigned int cmd, compat_ulong_t arg)'. I > was expecting the second parameter, @cmd, to be a long type in the > normal definition, but it is an int type in both cases. It looks like > it has been that way long enough that it is correct, but I'm a little > lost ... Since @arg might be a pointer to some struct, @arg needs to use a long type. But @cmd can remain 32bits for both 32bits/64bits kernels because @cmd is not a pointer, can't it? > I agree that it looks like Smack and TOMOYO should be fine, but I > would like to hear from Casey and Tetsuo to confirm. Fine for TOMOYO part, for TOMOYO treats @cmd as an integer.