Re: Fwd: [PATCH][SMB3 client] fix TCP timers deadlock after rmmod

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Greg KH <gregkh@linuxfoundation.org>
Date: Wed, 2 Apr 2025 22:32:58 +0100
> On Wed, Apr 02, 2025 at 01:50:05PM -0700, Kuniyuki Iwashima wrote:
> > From: Greg KH <gregkh@linuxfoundation.org>
> > Date: Wed, 2 Apr 2025 21:28:51 +0100
> > > On Wed, Apr 02, 2025 at 01:22:11PM -0700, Kuniyuki Iwashima wrote:
> > > > From: Greg KH <gregkh@linuxfoundation.org>
> > > > Date: Wed, 2 Apr 2025 21:15:58 +0100
> > > > > On Wed, Apr 02, 2025 at 01:09:19PM -0700, Kuniyuki Iwashima wrote:
> > > > > > From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > > > > > Date: Wed, 2 Apr 2025 16:18:37 +0100
> > > > > > > On Wed, Apr 02, 2025 at 05:15:44PM +0800, Wang Zhaolong wrote:
> > > > > > > > > On Wed, Apr 02, 2025 at 12:49:50PM +0800, Wang Zhaolong wrote:
> > > > > > > > > > Yes, it seems the previous description might not have been entirely clear.
> > > > > > > > > > I need to clearly point out that this patch, intended as the fix for CVE-2024-54680,
> > > > > > > > > > does not actually address any real issues. It also fails to resolve the null pointer
> > > > > > > > > > dereference problem within lockdep. On top of that, it has caused a series of
> > > > > > > > > > subsequent leakage issues.
> > > > > > > > > 
> > > > > > > > > If this cve does not actually fix anything, then we can easily reject
> > > > > > > > > it, please just let us know if that needs to happen here.
> > > > > > > > > 
> > > > > > > > > thanks,
> > > > > > > > > 
> > > > > > > > > greg k-h
> > > > > > > > Hi Greg,
> > > > > > > > 
> > > > > > > > Yes, I can confirm that the patch for CVE-2024-54680 (commit e9f2517a3e18)
> > > > > > > > should be rejected. Our analysis shows:
> > > > > > > > 
> > > > > > > > 1. It fails to address the actual null pointer dereference in lockdep
> > > > > > > > 
> > > > > > > > 2. It introduces multiple serious issues:
> > > > > > > >    1. A socket leak vulnerability as documented in bugzilla #219972
> > > > > > > >    2. Network namespace refcount imbalance issues as described in
> > > > > > > >      bugzilla #219792 (which required the follow-up mainline fix
> > > > > > > >      4e7f1644f2ac "smb: client: Fix netns refcount imbalance
> > > > > > > >      causing leaks and use-after-free")
> > > > > > > > 
> > > > > > > > The next thing we should probably do is:
> > > > > > > >    - Reverting e9f2517a3e18
> > > > > > > >    - Reverting the follow-up fix 4e7f1644f2ac, as it's trying to fix
> > > > > > > >      problems introduced by the problematic CVE patch
> > > > > > > 
> > > > > > > Great, can you please send patches now for both of these so we can
> > > > > > > backport them to the stable kernels properly?
> > > > > > 
> > > > > > Sent to CIFS tree:
> > > > > > https://lore.kernel.org/linux-cifs/20250402200319.2834-1-kuniyu@amazon.com/
> > > > > 
> > > > > You forgot to add a Cc: stable@ on the patches to ensure that they get
> > > > > picked up properly for all stable trees :(
> > > > 
> > > > Ah sorry, I did the same with netdev.  netdev patches usually do
> > > > not have the tag but are backported fine, maybe netdev local rule ?
> > > 
> > > Nope, that's the "old" way of dealing with netdev patches, the
> > > documentation was changed years ago, please always put a cc: stable on
> > > it.  Otherwise you are just at the whim of our "hey, I'm board, let's
> > > look for Fixes: only tags!" script to catch them, which will also never
> > > notify you of failures.
> > 
> > Good to know that, thanks!
> > 
> > My concern was that I could spam the list if I respin the patches,
> > and incomplete patch could be backported.
> > 
> > >From stable-kernel-rules.rst, such an accident can be prevented if
> > someone points out a problem within 48 hours ?
> > 
> > For example, if v1 is posted with Cc:stable, and a week later
> > v2 is posted, then the not-yet-upstreamed v1 could be backported ?
> > 
> 
> Anything can be asked to be applied to stable once it is in Linus's
> tree, but if you add the cc: stable stuff to the original patch, it will
> be done automatically for you.

Now I understood.  The process is triggered only after the patch
is merged to Linus' tree.  I assumed the workflow is triggered by
the patch email itself.

Thanks for explaining!