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DannyB2

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DannyB2
·4 tháng trước·discuss
AIs have no reason to want to harm annoying slow inefficient noisy smelly humans.
DannyB2
·8 tháng trước·discuss
Being liberal in what you accept is fine, as long as what you accept is precisely documented. But then, is that actually "being liberal"?

Better advice is to not do something unexpected -- even if that unexpected result is clearly documented, but someone did not read it.
DannyB2
·8 tháng trước·discuss
It was a denial of service attack, not in the sense of soaking up my brain cells solving puzzles, but in causing me to devise and program my own solver. (In Java, text console only.) Once I wrote a solver, I felt as if I had solved all puzzles.

Then I got interested in devising puzzles with multiple solutions. Not too difficult. But making a few puzzles with two solutions was fun.

Experiment_203(

   " 1 . . | 2 . 8 | . . 9 "+
   " . 8 . | . . . | . 3 . "+
   " . . 7 | . 1 . | 2 . . "+
   //------+-------+--------
   " 4 . . | 1 2 3 | . . 6 "+
   " . . 2 | 4 5 6 | 9 . . "+
   " 6 . . | 7 8 9 | . . 4 "+
   //------+-------+--------
   " . . 6 | . 4 . | 8 . . "+
   " . 2 . | . . . | . 7 . "+
   " 9 . . | 8 . 2 | . . 1 "
  ),
// Solution #1. Found in 0 days 00:00:00.004.

// 245 boards examined so far.

   1 6 5 | 2 3 8 | 7 4 9
   2 8 4 | 6 9 7 | 1 3 5
   3 9 7 | 5 1 4 | 2 6 8
   ------+-------+------
   4 7 9 | 1 2 3 | 5 8 6
   8 3 2 | 4 5 6 | 9 1 7
   6 5 1 | 7 8 9 | 3 2 4
   ------+-------+------
   7 1 6 | 3 4 5 | 8 9 2
   5 2 8 | 9 6 1 | 4 7 3
   9 4 3 | 8 7 2 | 6 5 1


// Solution #2. Found in 0 days 00:00:00.001.

// 287 boards examined so far.

   1 6 5 | 2 3 8 | 7 4 9
   2 8 4 | 9 6 7 | 1 3 5  // <-- 9 6 7 instead of 6 9 7
   3 9 7 | 5 1 4 | 2 6 8
   ------+-------+------
   4 7 9 | 1 2 3 | 5 8 6
   8 3 2 | 4 5 6 | 9 1 7
   6 5 1 | 7 8 9 | 3 2 4
   ------+-------+------
   7 1 6 | 3 4 5 | 8 9 2
   5 2 8 | 6 9 1 | 4 7 3  // <-- 6 9 1 instead of 9 6 1
   9 4 3 | 8 7 2 | 6 5 1


   2 total solutions found.
   304 total boards examined.
   Total time 0 days 00:00:00.041.
Then I got to looking at difficult puzzles on the web. Apparently AI escargot is the world's most difficult. (And the site http://www.aisudoku.com/index_en.html says I can't publish the board). So I'll only publish the stats of applying my solver to it.

  Solution #1.  Found in 0 days 00:00:00.029.
  3,906 boards examined so far.

  1 total solutions found.
  7,832 total boards examined.
  Total time 0 days 00:00:00.085.
DannyB2
·8 tháng trước·discuss
Ignorance is bliss?
DannyB2
·9 năm trước·discuss
There is this thing called "return oriented programming". You write your program as a series of addresses that are smashed onto the stack through some other type of vulnerability. When the current function returns, it returns to an address of your choosing. That address points to the tail end of some known existing function, such as in the C library and other libraries. When the tail end of that function returns, it executes your next "instruction" which is merely the next return address on the stack.

The first "instruction" of your program is the last address on the stack, in the list of addresses you pushed to the stack.

You are executing code, but you did not inject any executable code, you did not need to modify any existing code pages (which are probably read only), you did not need to attempt to execute code out of a data page (which is probably marked non executable).

Address Space Layout Randomization is a way to prevent the "return oriented programming" attack. When a process is launched, the address space is randomly laid out so that the attacker cannot know which address in memory the std C lib printf function will be located at -- in this process.

Now let's think about the kernel. If you could know all of the addresses of important kernel routines, you could potentially execute a "return oriented programming" attack against the kernel with kernel privileges. Without modifying or injecting any kernel level code. These hardware vulnerabilities allow user space code to deduce information about kernel space addresses.

Now that's a lot of hoops to jump through in order to execute an attack. But there are people prepared to expend this and even more effort in order to do so. Well funded and well staffed adversaries who would stop at nothing in order to access more and better pr0n collections.
DannyB2
·9 năm trước·discuss
This probably does not change Bill Gates' enjoyment of day to day life, or lack thereof, whatever the case may be. It depends on whether Bill Gates is obsessed by these kinds of facts, or whether he can enjoy life without a tiny hand size measuring contest.