GNU bug report logs - #13074
VM Segfaults with Bad `Call' Instruction

Previous Next

Full log

View this message in rfc822 format

From: Noah Lavine <noah.b.lavine <at> gmail.com>
To: 13074 <at> debbugs.gnu.org
Subject: bug#13074: VM Segfaults with Bad `Call' Instruction
Date: Mon, 3 Dec 2012 22:06:28 -0500

[Message part 1 (text/plain, inline)]

Hello,

This is an interesting bug, because the only way to hit it (as far as I can
tell) is to mess up when writing a compiler. However, I did mess up, and I
discover that I can generate a `call' instruction in the trunk VM where the
procedure to call will be 0x0. Then the VM will try to check whether the
procedure is really a procedure, and Guile will segfault at line 796 of
v-i-system.c.

I think the correct behavior would be to throw a `vm-bad-instruction' error
instead. The fix should be pretty simple - just check if program is 0x0 and
jump to vm-bad-instruction in that case.

Noah

[Message part 2 (text/html, inline)]

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.