patch kernel question

zuessh · 12-20-2003, 06:15 PM

Cant explain why this time was different but it is now working

I changed the boot = linux to boot = bootdamnit
reran lilo -r /hd/etc and I got the following
warning LBA32 addressing assumed
added bootdamnit *
added failsafe
added memtest86

I rebooted and it worked, dont know what was different this time than last time I ran the same command (reply 7).

Thanks again bash for all your help

One last question; the main reason i did the kernel upgrade was for the brk vuln. How can i tell if my kernel is safe now?

/bin/bash · 12-20-2003, 08:42 PM

bootdamnit hehehe I'll have to remember that one!

If you are referring to the do_brk() function then look at this thread. If you look at /usr/src/linux/mm/mmap.c and at line 1026 you will find the do_brk() function. If it looks like this then it's OK.

Code:

/*
 *  this is really a simplified "do_mmap".  it only handles
 *  anonymous maps.  eventually we may be able to do some
 *  brk-specific accounting here.
 */
unsigned long do_brk(unsigned long addr, unsigned long len)
{
	struct mm_struct * mm = current->mm;
	struct vm_area_struct * vma, * prev;
	unsigned long flags;
	rb_node_t ** rb_link, * rb_parent;

	len = PAGE_ALIGN(len);
	if (!len)
		return addr;

	if ((addr + len) > TASK_SIZE || (addr + len) < addr)
		return -EINVAL;

What's in bold is what was added to fix the problem.