Re: [PATCH 0/2] cifs: Revert bogus fix for CVE-2024-54680 and its followup commit.

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Steve French <smfrench@gmail.com>
Date: Wed, 2 Apr 2025 20:14:03 -0500
> might be helpful if there were eBPF tracepoints for some of this that
> would be able to log warnings optionally if refcount issue on
> sock_release and/or rmmod

I just posted a fix and there explained that the socket and module
refcnt discrepancy is totally fine without LOCKDEP.

https://lore.kernel.org/netdev/20250403020837.51664-1-kuniyu@amazon.com/

So, in this case, the helpful warning is one logged by hlock_class().

As it returns NULL and triggers null-ptr-derf, it means something went
wrong, and I guess it was acceptable because LOCKDEP is not enabled in
production.

Btw, I posted v2 with Cc: stable tags as requested by Greg, so please
drop this v1.

https://lore.kernel.org/linux-cifs/20250402202714.6799-1-kuniyu@amazon.com/

Thanks!

> 
> 
> On Wed, Apr 2, 2025 at 3:03 PM Kuniyuki Iwashima <kuniyu@amazon.com> wrote:
> >
> > Commit e9f2517a3e18 ("smb: client: fix TCP timers deadlock after
> > rmmod") was not only a bogus fix for the LOCKDEP issue but also
> > introduced a real TCP socket leak.
> >
> > I'm working on the LOCKDEP fix on the networking side, so let's
> > revert the commit and its followup fix.
> >
> > For details, please see each commit.
> >
> >
> > Kuniyuki Iwashima (2):
> >   Revert "smb: client: Fix netns refcount imbalance causing leaks and
> >     use-after-free"
> >   Revert "smb: client: fix TCP timers deadlock after rmmod"
> >
> >  fs/smb/client/connect.c | 34 +++++++++-------------------------
> >  1 file changed, 9 insertions(+), 25 deletions(-)
> >
> > --
> > 2.48.1