Re: NFS PANIC and FIX in 2.4

[Neil Brown]

On Saturday June 9, [e-mail] wrote:
> Hi All,
> 
> I get this panic running RedHat 2.4.3-6:
> 
> Unable to handle kernel NULL pointer dereference at virtual address 00000004
> c014b13d

....
> 
> The problem is pretty specific to 2.4.3-6 because it has code in list_del() to 
> null out the prev and next pointers (I don't know where they picked it up, but 
> its gone in 2.4.5).   However, it exposes a bug in NFS, namely that d_splice() 
> also calls list_del() on tdentry->d_child.  This shouldn't be done because it 
> makes the d_child list invalid, so any subsequent call to list_del on d_child 
> could panic.  I think the correct fix (attached below) is to change the NFS 
> list_del to list_del_init.

Yep, that looks good.  I'll forward it to Linus with a few other fixes
I have pending.

Thanks,

NeilBrown