bin/38182: fsck_msdos requires too many resources

[rillig%NetBSD.org@localhost]

>Number:         38182
>Category:       bin
>Synopsis:       fsck_msdos requires too many resources
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Mar 06 09:15:01 +0000 2008
>Originator:     Roland Illig
>Release:        NetBSD 4.99.30
>Organization:
>Environment:
NetBSD bacc.roland-illig.de 4.99.30 NetBSD 4.99.30 (GENERIC) #2: Fri Aug 31 
20:40:16 CEST 2007  
build%bacc.roland-illig.de@localhost:/home/scratch/build/NetBSD/2007-08/work/sys/arch/i386/compile/GENERIC
 i386
>Description:
When starting fsck_msdos, it allocates the memory for the FATs to compare them. 
I have a 110 GB MSDOS partition for which this amounts to about 1 GB of RAM 
being consumed. Since the swap space is usually available, this is not a 
problem, but when it is run during booting, it allocates the memory using the 
break() function, which cannot allocate that much memory at one time. I'll 
append the exact error message later.

>How-To-Repeat:

>Fix:
Don't load the complete FATs into memory, but compare them block-wise.