[BUG] Out of bound read of size 1 in __d_alloc function which further leads to __default_memcpy function

[Jules Maselbas]

Hi,

On Fri, May 07, 2021 at 12:58:30PM +0200, Sascha Hauer wrote:
> Hi,
> 
> On Sun, Apr 18, 2021 at 01:10:10AM +0530, Neeraj Pal wrote:
> > Hi,
> > 
> > I have found the Out of bound read issue of size 1 when argv[2] is "" in
> > __d_alloc function fs/fs.c:1254 which further goes
> > and crashes into  __default_memcpy call lib/string.c:562
> > 
> > Tested on:
> > - barebox-2021.04.0
> > - git commit af0f068a6edad45b033e772056ac0352e1ba3613
> 
> I can reproduce this here. Thanks for reporting it. I just sent out a
> series fixing this issue, you are on Cc:
I think this should also be fixed by the patch I've sent:
(74946415a "fs: Fix link_path_walk to return -ENOENT on empty path")

This patch might not have fixed this exact case when running the nfs
command. Have you been able to repoduce this issue with this patch
applied ?

I've havn't tried to setup a net interface to debug nfs commandi,
instead I was using simpler command such as `md5sum ""`.

Best,
Jules