Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 3 Feb 1997 14:39:02 -0800 (PST)
From:      javaman@halcyon.com
To:        freebsd-gnats-submit@freebsd.org
Subject:   kern/2649: accessing floppy using wrong major number causes crash at next access
Message-ID:  <199702032239.OAA25284@freefall.freebsd.org>
Resent-Message-ID: <199702032240.OAA25343@freefall.freebsd.org>

next in thread | raw e-mail | index | archive | help

>Number:         2649
>Category:       kern
>Synopsis:       accessing floppy using wrong major number causes crash at next access
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Feb  3 14:40:01 PST 1997
>Last-Modified:
>Originator:     David DeLaune
>Organization:
>Release:        2.2-BETA_A
>Environment:
FreeBSD mercury.org 2.2-BETA_A FreeBSD 2.2-BETA_A #0:
Mon Jan 27 21:03:32 PST 1997     
root@mercury.org:/usr/src/sys/compile/MYKERNEL  i386
>Description:
Accessing the floppy using the wrong /dev/fdX.XXXX will cause a crash
at the next access.  I was using mtools at the time, but I have repeated
this problem using dd as well.  I first access a 720K floppy as a 1440K
floppy which gives the following error:
# mdir 
# Feb 3 13:36:35 mercury/kernel: fd0c: hard error reading fsbn 0 of 0-3
(ST040)<abnrml> ST1 1<no_Am> ST2 0 cyl 0 hd 0 sec 1

Then I try to access the floppy using the correct device type (720K defined
in mtools.conf as drive b: file="/dev/fd0.720" exclusive)

Fatal Trap 9: general protection fault while in kernel mode
instruction pointer                         = 0x8:0xf010def1
stack pointer                               = 0x10: 0xefbffd64
frame pointer                               = 0x10: 0xefbffd8c
code segment                                = base 0x0, limit 0xfffff, type 0x1b
processor eflags                            = interrupt enabled, resume, IOPL=0
int mask                                    = net tty bio
panic: general protection fault

syncing disk 10 10 10 10 .......<several times>
giving up
>How-To-Repeat:
I can repeat this by accessing fd0 with the wrong dev for the floppy type
that is in the drive, on the second access using dd or mtools.  Have not
tried mount or fdformat, but I will.	
>Fix:

>Audit-Trail:
>Unformatted:



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199702032239.OAA25284>