On Mon, 2025-03-17 at 21:28 +0000, Trond Myklebust wrote: > On Mon, 2025-03-17 at 17:00 -0400, Jeff Layton wrote: > > With the move to having sunrpc client xprts not hold active > > references > > to the net namespace, there is no need to upgrade the socket's > > reference > > in xs_create_sock. Just keep the passive reference instead. > > > > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> > > --- > > net/sunrpc/xprtsock.c | 3 --- > > 1 file changed, 3 deletions(-) > > > > diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c > > index > > 83cc095846d356f24aed26e2f98525662a6cff1f..0c3d7552f772d6f8477a3aed8f0 > > c513b62cdf589 100644 > > --- a/net/sunrpc/xprtsock.c > > +++ b/net/sunrpc/xprtsock.c > > @@ -1941,9 +1941,6 @@ static struct socket *xs_create_sock(struct > > rpc_xprt *xprt, > > goto out; > > } > > > > - if (protocol == IPPROTO_TCP) > > - sk_net_refcnt_upgrade(sock->sk); > > - > > filp = sock_alloc_file(sock, O_NONBLOCK, NULL); > > if (IS_ERR(filp)) > > return ERR_CAST(filp); > > > > Is this not going to reintroduce the bug described by > https://lore.kernel.org/netdev/67b72aeb.050a0220.14d86d.0283.GAE@xxxxxxxxxx/T/#u > ? > > As I understand it, the problem has nothing to do with whether or not > NFS or the RPC layer holds a reference to the net namespace, but rather > whether there are still packets in the socket queues at the time when > that net namespace is being freed. > > I don't think so. That syzkaller report was closed by this patch: 5c70eb5c593d net: better track kernel sockets lifetime That says: "To fix this, make sure that kernel sockets own a reference on net passive." With this, we still do keep a passive reference on the net in the socket, which I think is enough. That said, I'd appreciate a look at this from the netdev folks. -- Jeff Layton <jlayton@xxxxxxxxxx>
