From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 69B3F79C2; Sat, 30 Dec 2023 12:05:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="c/qm8vL0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6A18C433C7; Sat, 30 Dec 2023 12:05:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1703937948; bh=chiuZF5Zh9OeEqcN6RoT0PWxdUuFMMu8JkX0b8j5MKQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c/qm8vL0veFQhqcnqq8kxi68R6/jPRYmyFagGZxHSE9ssb+XNc7Y5fJ5CUS+i5DkE 5ZyBRJgGuKQ66Xa6AlaQPq/8FDDcbXpYsya/6v2HRPrKSIZGMN5lp0CacQj42mVLHJ V6/AU9OpoR/+tcySoZFCM3QanrJIorSAl/7vNCk8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, NeilBrown , Jeff Layton , Chuck Lever Subject: [PATCH 6.6 124/156] nfsd: call nfsd_last_thread() before final nfsd_put() Date: Sat, 30 Dec 2023 11:59:38 +0000 Message-ID: <20231230115816.427046313@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231230115812.333117904@linuxfoundation.org> References: <20231230115812.333117904@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: NeilBrown commit 2a501f55cd641eb4d3c16a2eab0d678693fac663 upstream. If write_ports_addfd or write_ports_addxprt fail, they call nfsd_put() without calling nfsd_last_thread(). This leaves nn->nfsd_serv pointing to a structure that has been freed. So remove 'static' from nfsd_last_thread() and call it when the nfsd_serv is about to be destroyed. Fixes: ec52361df99b ("SUNRPC: stop using ->sv_nrthreads as a refcount") Signed-off-by: NeilBrown Reviewed-by: Jeff Layton Cc: Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfsctl.c | 9 +++++++-- fs/nfsd/nfsd.h | 1 + fs/nfsd/nfssvc.c | 2 +- 3 files changed, 9 insertions(+), 3 deletions(-) --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -704,8 +704,10 @@ static ssize_t __write_ports_addfd(char err = svc_addsock(nn->nfsd_serv, net, fd, buf, SIMPLE_TRANSACTION_LIMIT, cred); - if (err >= 0 && - !nn->nfsd_serv->sv_nrthreads && !xchg(&nn->keep_active, 1)) + if (err < 0 && !nn->nfsd_serv->sv_nrthreads && !nn->keep_active) + nfsd_last_thread(net); + else if (err >= 0 && + !nn->nfsd_serv->sv_nrthreads && !xchg(&nn->keep_active, 1)) svc_get(nn->nfsd_serv); nfsd_put(net); @@ -756,6 +758,9 @@ out_close: svc_xprt_put(xprt); } out_err: + if (!nn->nfsd_serv->sv_nrthreads && !nn->keep_active) + nfsd_last_thread(net); + nfsd_put(net); return err; } --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -138,6 +138,7 @@ int nfsd_vers(struct nfsd_net *nn, int v int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change); void nfsd_reset_versions(struct nfsd_net *nn); int nfsd_create_serv(struct net *net); +void nfsd_last_thread(struct net *net); extern int nfsd_max_blksize; --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -542,7 +542,7 @@ static struct notifier_block nfsd_inet6a /* Only used under nfsd_mutex, so this atomic may be overkill: */ static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0); -static void nfsd_last_thread(struct net *net) +void nfsd_last_thread(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct svc_serv *serv = nn->nfsd_serv;