Re: [RFC-PATCH] nfsd: when unhashing openowners, increment openowner's refcount

["J. Bruce Fields" <bfields@fieldses.org>]

On Mon, Aug 26, 2019 at 09:39:51AM -0400, J. Bruce Fields wrote:
> On Sun, Aug 25, 2019 at 01:12:34PM +0300, Alex Lyakas wrote:
> > You are listed as maintainers of nfsd. Can you please take a look at
> > the below patch?
> 
> Thanks!
> 
> I take it this was found by some kind of code analysis or fuzzing, not
> use in production?
> 
> Asking because I've been considering just deprecating it, so:

So, unless someone objects I'd like to queue this up for 5.4.

--b.

commit 9d60d93198c6
Author: J. Bruce Fields <bfields@redhat.com>
Date:   Mon Aug 26 10:28:58 2019 -0400

    Deprecate nfsd fault injection
    
    This is only useful for client testing.  I haven't really maintained it,
    and reference counting and locking are wrong at this point.  You can get
    some of the same functionality now from nfsd/clients/.
    
    It was a good idea but I think its time has passed.
    
    In the unlikely event of users, hopefully the BROKEN dependency will
    prompt them to speak up.  Otherwise I expect to remove it soon.
    
    Reported-by: Alex Lyakas <alex@zadara.com>
    Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/Kconfig b/fs/nfsd/Kconfig
index bff8456220e0..10cefb0c07c7 100644
--- a/fs/nfsd/Kconfig
+++ b/fs/nfsd/Kconfig
@@ -148,7 +148,7 @@ config NFSD_V4_SECURITY_LABEL
 
 config NFSD_FAULT_INJECTION
 	bool "NFS server manual fault injection"
-	depends on NFSD_V4 && DEBUG_KERNEL && DEBUG_FS
+	depends on NFSD_V4 && DEBUG_KERNEL && DEBUG_FS && BROKEN
 	help
 	  This option enables support for manually injecting faults
 	  into the NFS server.  This is intended to be used for