[Linux-cluster] Re: [PATCH] DLM: fix a couple of races

[David Teigland]

On Fri, May 04, 2007 at 09:49:45PM +0530, Satyam Sharma wrote:
> Hi,
> 
> There are the following two trivially-fixed races in fs/dlm/config.c:
> 
> 1. The configfs subsystem semaphore must be held by the caller when 
> calling config_group_find_obj(). It's needed to walk the subsystem 
> hierarchy without racing with a simultaneous mkdir(2) or rmdir(2). I 
> looked around to see if there was some other way we were avoiding this 
> race, but couldn't find any.
> 
> 2. get_comm() does hold the subsystem semaphore but lets go too soon -- 
> before grabbing a reference on the found config_item. A concurrent 
> rmdir(2) could come and release the comm after the up() but before the 
> config_item_get().
> 
> Patch that fixes both these bugs below.

Thanks, Steve should be able to throw this into one of his git trees.

Dave