Swap Bug Massive EXT3 Corruption on FC4 with 2.6.14 update

Swap Bug Massive EXT3 Corruption on FC4 with 2.6.14 update

[jmerkey]

When instaling FC4 on a system which already has FC2 previously 
installed on a second hard drive, the install program becomes
confused and assigns the swap partition to the FC2 system when 
installing FC4.  The kernel then IGNORES the size extents set
for the swap partition (in this case FC2 was set to 1024, FC4 was set to 
2048) and allows the cross mounted swap to grow into
the next partition, totally corrupting the root drive (/) by allowing 
the swap segment to grow into the root drive and overwrite
it.

To reproduce, install FC2 on an /dev/hda device with defaults, then 
install FC4 on a /dev/hdb device, build the 2.6.14 update for
FC4 and watch your data disappear.

Jeff

Re: Swap Bug Massive EXT3 Corruption on FC4 with 2.6.14 update

[Alan Cox]

On Iau, 2005-11-17 at 11:05 -0700, jmerkey wrote:
> To reproduce, install FC2 on an /dev/hda device with defaults, then 
> install FC4 on a /dev/hdb device, build the 2.6.14 update for
> FC4 and watch your data disappear.

Should be reported in the FC bugzilla although I've not been able to
reproduce it.

Re: Swap Bug Massive EXT3 Corruption on FC4 with 2.6.14 update

[jmerkey]

Alan Cox wrote:

>On Iau, 2005-11-17 at 11:05 -0700, jmerkey wrote:
>  
>
>>To reproduce, install FC2 on an /dev/hda device with defaults, then 
>>install FC4 on a /dev/hdb device, build the 2.6.14 update for
>>FC4 and watch your data disappear.
>>    
>>
>
>Should be reported in the FC bugzilla although I've not been able to
>reproduce it.
>
>
>  
>

Alan,

I'll report over there.  I reproduced it with an install of Suse 10.0 
and FC4 and got to the bottom of it.  During install of FC4, anaconda 
allocates
the swap partitions assigned to Suse 10.0 on /dev/hda (or any swap 
partitions on the primary drive) for use during the install.  After the 
install
completes, FC4 uses this LABEL-SWAP-hda2 (etc.) method for determining 
which partitions to use for swap.  What happened here it turned
out was not related to swap extents, but misidentifcation of which 
partition was assigned this LABEL-XXX tag.  Upon first boot of FC4,
it allocated /dev/hda6 (the / partitition) as swap and started swapping 
to the / partition for Suse 10.0.  I first saw it when I installed FC4 
on a system
with FC2.  After FC2 / partition got trashed, I reinstalled with Suse 
10.0 (since I am porting DSFS to all of these distributions) and then 
reinstalled
FC4 on /dev/hdb -- same thing happened again. 

I just finished reinstalling Suse 10.0 and tried with FC2 on /dev/hdb.  
FC2 does the same thing and gets mixed on on Swap on the /dev/hda 
device, but this time, it did not corrupt the Suse 10.0 on /dev/hda.  
This appears to be a bug in anaconda and the setup for the FCX 
distributions.  ES and AS probably do the same thing since they use 
anaconda, so I would have someone look into this.

Jeff

Re: Swap Bug Massive EXT3 Corruption on FC4 with 2.6.14 update

[jmerkey]

jmerkey wrote:

> Alan Cox wrote:
>
>> On Iau, 2005-11-17 at 11:05 -0700, jmerkey wrote:
>>  
>>
>>> To reproduce, install FC2 on an /dev/hda device with defaults, then 
>>> install FC4 on a /dev/hdb device, build the 2.6.14 update for
>>> FC4 and watch your data disappear.
>>>   
>>
>>
>> Should be reported in the FC bugzilla although I've not been able to
>> reproduce it.
>>
>>
>>  
>>
>
> Alan,
>
> I'll report over there.  I reproduced it with an install of Suse 10.0 
> and FC4 and got to the bottom of it.  During install of FC4, anaconda 
> allocates
> the swap partitions assigned to Suse 10.0 on /dev/hda (or any swap 
> partitions on the primary drive) for use during the install.  After 
> the install
> completes, FC4 uses this LABEL-SWAP-hda2 (etc.) method for determining 
> which partitions to use for swap.  What happened here it turned
> out was not related to swap extents, but misidentifcation of which 
> partition was assigned this LABEL-XXX tag.  Upon first boot of FC4,
> it allocated /dev/hda6 (the / partitition) as swap and started 
> swapping to the / partition for Suse 10.0.  I first saw it when I 
> installed FC4 on a system
> with FC2.  After FC2 / partition got trashed, I reinstalled with Suse 
> 10.0 (since I am porting DSFS to all of these distributions) and then 
> reinstalled
> FC4 on /dev/hdb -- same thing happened again.
> I just finished reinstalling Suse 10.0 and tried with FC2 on 
> /dev/hdb.  FC2 does the same thing and gets mixed on on Swap on the 
> /dev/hda device, but this time, it did not corrupt the Suse 10.0 on 
> /dev/hda.  This appears to be a bug in anaconda and the setup for the 
> FCX distributions.  ES and AS probably do the same thing since they 
> use anaconda, so I would have someone look into this.
>
> Jeff
>
NOTE;  One this that's unique in this case is that after I instal DSFS 
rpms, I remove these LABEL-XXX constructs from the grub.conf and 
/etc/fstab files and use the actual device names /dev/hdX.  It seems 
related to removing these labels in a running distribution.

Jeff