Re: "Exception at ..." with 2.1.9 and 2.1.10 kernels

Systemkennung Linux (
Mon, 18 Nov 1996 00:53:36 +0100 (MET)

> 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