Re: [patch 08/15] fat: dont call notify_change

[OGAWA Hirofumi]

Miklos Szeredi <miklos@xxxxxxxxxx> writes:

> security_inode_setattr() will call into the security module (selinux,
> smack, apparmor) to check if the file mode change is permitted or not.
> It's not really applicable to this case, since AFAICS the mode change
> here is just a side effect of the attribute change.

Yes.

> If it's not just a side effect, but another way to change the file
> mode, then the whole code is very wrong.  chmod() is perfectly fine
> for changing the file mode, there's no need for a separate ioctl to
> perform exactly the same task.

FAT doesn't have permission, it has just some flags. hidden, system,
read-only, etc., and FAT driver maps read-only to permission bit of
file/dir. Mainly this ioctl is to change FAT specific flags, but doesn't
handle read-only flag as special.

As result, this ioctl change permission.
-- 
OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/