Re: "Exception at ..." with 2.1.9 and 2.1.10 kernels
Wed, 20 Nov 1996 01:20:02 GMT

On Mon, 18 Nov 1996 00:53:36 +0100 (MET), you wrote:

> > Sorry, I'm still not buying that. Getname comes from linux/fs/namei.c. In
> > the code, it says that it is copying from user-space to kernel-space for
> > "efficiency." Exactly how is this a user problem? User code doesn't know
> > about kernel space.
> But the kernel knows about userspace.
> > I still say something's goofy.
> Goofy lusercode. For example look into sys_open, the open(2) syscall and
> look what would happen if you pass bad parameters, for example a NULL
> pointer: the kernel passes this pointer to getname().
> Or even easier, write a program that passes a NULL pointer
> to open(2)/read(2)/write(2) etc. What happens? You get one of these
> nice messages.
> Btw, some days ago someone posted a long and quite good article about
> this topic which describes in detail how the new way to access user space
> works.
> Ralf
You're right. I'm wrong. Sorry about the militancy.