Bug 17040

Summary: Kernel auto-reboot on write to write protected floppy.
Product: Base System Reporter: chris.smith <chris.smith>
Component: i386Assignee: freebsd-bugs (Nobody) <bugs>
Status: Closed FIXED    
Severity: Affects Only Me    
Priority: Normal    
Version: 3.4-RELEASE   
Hardware: Any   
OS: Any   

Description chris.smith 2000-02-28 10:10:01 UTC 
When writing an image to a floppy which is write protected!) using the dd command, there appears to be a buffer related problem and the system automatically reboots itself.

Fix: 

No fix known.
How-To-Repeat: Get an _OpenBSD_ .fs installation image for i386 architecture, write protect a floppy and poke it in the drive and as root execute the following command:-

# dd if=floppy26.fs of=/dev/fd0

..20 secs later, the kernel reboots the system.  Help!  this does this in userland too if I was kind enough to give the user access to the floppy drive.  This could be used agains a FreeBSD box as an attack.
Comment 1 Sheldon Hearn freebsd_committer freebsd_triage 2000-02-29 14:30:39 UTC 
State Changed
From-To: open->closed

Duplicate of numerous other PRs containing much more detail on 
the problem.  The short answer is "be aware of the problem and 
don't do that".  The long answer is that it's a lot of work to 
fix. :-)